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Abstract 1210 Poster Board I-232 Allogeneic hematopoietic cell transplantation (HCT) with a conventional, high intensity conditioning regimen is an established approach for potentially curing patients (pts) with high-risk acute lymphoblastic leukemia (ALL). However, many pts are not candidates for high intensity conditioning HCT. The use of a reduced intensity conditioning (RIC) for ALL may provide an opportunity to decrease the toxicity of an intense conditioning regimen yet maintain the potential graft vs. leukemia effect. Here we describe the transplantation course and overall survival (OS) of 50 consecutive pts with high-risk ALL that were treated in a multi-center protocol of RIC and allogeneic HCT between February 2000 and August 2008. The median age was 56 (range, 7-69) years. All pts had cytogenetic analysis of bone marrow (BM) at diagnosis. 26 pts had Philadelphia chromosome positive (Ph+) ALL: 18 were in first complete remission (CR1) and 8 were in CR>1 at the time of HCT. 24 pts had Ph–ALL, 12 pts were in CR1 and 12 pts were in CR>1. Pts. were conditioned with fludarabine 90mg/m2 and 2 Gy total body irradiation. Nine pts received peripheral blood stem cells (PBSC) from HLA-identical siblings, 41 pts received grafts from unrelated donors (35 HLA-matched PBSC, 1 BM and 5 received 1-HLA-Ag mismatched PBSC). After the introduction of imatinib mesylate, 19 of the 26 pts with Ph+ALL participated in a study evaluating the safety and efficacy of imatinib starting at day +15 after HCT. Post-grafting immunosuppression consisted of combined mycophenolate mofetil and cyclosporine. Median follow up for surviving pts was 31 months (range, 12-91). One pt had graft rejection (BM recipient). 25 pts (50%) and 4 pts (8%) developed grades 2 and 3-4 acute graft-versus-host disease (GVHD), respectively. Chronic GVHD occurred in 24 pts (53% of pts surviving > 100 days); 15 pts (30%) developed extensive chronic GVHD. 19 pts (38%) relapsed at a median of 4.5 (range, 0.4-59) months. Non relapse mortality (NRM) at 2 and 5 years was 26% and 31%, respectively. Progression-free survival was very similar to OS. For all 50 pts, OS at 2 and 5 years was 37% and 27%, respectively. For pts in CR1 (n=30), OS was 52% and 41%, respectively. In contrast, OS for pts >CR1 (n=20) was significantly lower (13% and 7%, respectively, p=.003). For pts with Ph–ALL, OS was 29%, unchanged at both 2 and 5 years. Those in CR1 had improved OS compared with pts >CR1 (48% vs. 11% unchanged at both 2 and 5 years, respectively, p=0.07, Figure). OS for the 26 pts with Ph+ALL at 2 and 5 years was 45% and 27%, respectively. OS at 2 and 5 years for pts treated with imatinib after HCT was 52% and 43%, respectively, this was superior to the OS for pts with Ph+ALL that did not receive imatinib (p=0.03, Figure). For Ph+ALL pts in CR1 who had no evidence of minimal residual disease (MRD negative, detection by flow cytometry and FISH) prior to HCT and received imatinib (n=12), the OS was 67%, unchanged at both 2 and 5 years. In contrast, the pts with MRD negative Ph+ALL in CR1 who did not receive imatinib (n=4) had OS at 2 and 5 years of 50% and 0%, respectively. Imatinib after HCT was well tolerated: 3 pts required early stopping of imatinib due to associated reversible toxicity. We conclude that RIC with allogeneic HCT is a feasible treatment option that offers durable disease control, particularly for high-risk pts in CR1. The combination of post-transplant imatinib with RIC for Ph+ALL contributed to a substantially improved OS. Disclosures: Off Label Use: Imatinib - post-grafting treatment. Mycophenolate mofetil - immunosuppression after HCT.

Abstract 4332 Allogeneic SCT is widely considered the therapy most likely to prolong survival in pts with AML in first CR(CR1) or relapse (REL). Questions have arisen regarding the frequency with which the procedure is undertaken in a defined population of pts presenting with newly-diagnosed AML and subsequently followed through REL and after, or in pts presenting in REL. We first analyzed 26 consecutive UW pts age < 70 who did not have CBF AML, who were not NPM1+/FLT3,- and who achieved CR1 with at least 4 months have elapsing from presentation date. These patients would typically be considered candidates for SCT in CR1 Eleven of the 26(42%, 95% CI 23-63%) received SCT at a median of 3.5 months (range 0.5-9.0) from CR date. Rates of SCT were 42% both in pts age Disclosures: No relevant conflicts of interest to declare.

Abstract 2227 Poster Board II-204 Acute graft-versus-host disease (GVHD) contributes to morbidity and mortality after allogeneic hematopoietic cell transplantation (HCT) and more effective prevention and treatment strategies are needed. The 3-hydroxy-3-methylglutaryl coenzyme A-reductase inhibitors (statins) have been shown to possess immunomodulatory properties in vitro and in vivo. To determine whether donor or recipient statin use may affect the risk of GVHD, we retrospectively analyzed outcomes among 567 patients with hematologic malignancies who had hematopoietic cell transplantation from HLA-matched related donors at a single institution between 2001 and 2007. Compared to allografts where neither the donor nor recipient was treated with a statin at the time of transplant (n=464), statin use by the donor and not the recipient (n=75) was associated with a profoundly decreased risk of grade 3-4 acute GVHD (multivariate hazard ratio [HR], 0.28; 95= confidence interval [CI], 0.1-0.9; p=0.03) (Table). Statin use by both donor and recipient (n=12) was suggestively associated with a decreased risk of grade 3-4 acute GVHD (HR, 0.00; 95= CI, undefined; p=0.06), while statin use by the recipient and not the donor (n=16) did not confer GVHD-protection. Risks of chronic GVHD, recurrent malignancy, non-relapse mortality and overall mortality were not significantly affected by donor or recipient statin exposure. Statin-associated GVHD-protection was restricted to recipients with cyclosporine-based postgrafting immunosuppression (n=417; 74=) and was not observed among those given tacrolimus (significance of effect modification: cyclosporine vs. tacrolimus, p=0.009). These results suggest that donor statin treatment may be a promising strategy for preventing severe acute GVHD without compromising immunologic control of the underlying malignancy. Disclosures: No relevant conflicts of interest to declare.

Background: One strategy to decrease toxicity of conditioning regimens for hematopoietic cell transplantation (HCT) has been the use of radiation targeted systemically with radionuclide-labeled mAbs. While mAb labeled with β-emitting radionuclides have shown some efficacy, a more promising alternative is the use of α-particle emitters. In contrast to β-emitting radionuclides, the high linear energy transfer and short particle range of α-particles makes them particularly attractive for killing hematopoietic cells in the blood and marrow. We initially investigated bismuth-213 (213Bi)-labeled anti-CD45 mAb to replace total body irradiation (TBI) as nonmyeloablative conditioning for HCT. This conditioning successfully allowed sustained engraftment of allogeneic marrow in a canine model. However, the limited availability, very short t1/2 of 46 min, and cost to produce 213Bi place limitations in using this for clinical trials. Therefore, in this study we evaluated whether astatine-211 (211At), which has a longer half-life (t1/2 = 7.2 h) than 213Bi, gave comparable results when targeting hematopoietic cells in mice. Methods: After injecting with either 213Bi- or 211At-labeled rat anti-murine CD45 mAb 30F11, we evaluated myelosuppression and non-hematological toxicity with varying quantities of radioactivity (2, 10, 20, and 50 μCi) on 10 μg of 30F11 and 20 μCi of radioactivity on various quantities of 30F11 (2, 10 and 40 μg). We also evaluated biodistribution with 20 μCi on various quantities of 30F11. Results: In the biodistribution studies, the highest concentrations of radioactivity were seen in the spleen. The 211At concentrations ranged from 167–417 % injected dose/gram (% ID/g) at 24 h post injection while the 213Bi concentrations ranged from 45–166 % ID/g at 3 h post injection. This result suggested that the longer half-life of 211At might allow higher quantities of labeled mAb to reach the spleen before decay. Importantly, the longer half-life and higher spleen concentrations of 211At resulted in much higher radiation doses to that tissue (e.g. 29,450 cGy/50 mCi 211At administered vs. 1165 cGy/50 mCi 213Bi when 10 mg of mAb was employed). Significant cytopenias were not observed in any of the 213Bi groups. In contrast, lethal and irreversible myelosuppression was observed in the mice receiving 20 μCi 211At on 40 μg of 30F11 and 50 μCi 211At on 10 μg of 30F11 (minimal WBC counts 0.21 x 103 and 0.12 x 103/mm3, Plt counts 1.2 x 104 and 0.3 x 104/mm3, Hb levels 1.5 and 4.2 g/dl, respectively). In the mice receiving 20 μCi 211At on 10 μg of 30F11, significant but reversible pancytopenia was observed, with a nadir of 2 weeks after injection (minimal WBC count 0.45 x 103/mm3, Plt count 3.3 x 104/mm3, Hb level 9.9 g/dl). The pancytopenia resolved at 3 weeks after injection. The second highest concentrations both in 211At studies (18–50% ID/g) and 213Bi studies (19–33%ID/g) were observed in the liver. Reversible but severe acute hepatic toxicity (maximal AST 1329 IU/L and ALT 928 IU/L) occurred 3h after 50 μCi 213Bi but not after 50 μCi 211At injection. This was surprising given the fact that the estimated radiation dose given to liver after 50 mCi 213Bi injection was ~200 cGy whereas the liver dose ranged from 1350–2600 cGy for 50 mCi 211At (depending on the amount of labeled mAb). No significant renal toxicity was observed with either 211At or 213Bi labeled 30F11 during 8 weeks follow-up period. Conclusion: The study results suggest that we may be able to replace low dose TBI in nonmyeloablative conditioning regimens with much lower (mCi) quantities of 211At-labeled anti-CD45 mAb without major non-hematological toxicities compared to the same mAb labeled with 213Bi.

Allogeneic Hematopoietic Cell Transplants in Patients with Myelofibrosis ≥ 60 years of age. Primary myelofibrosis (PMF) and myelofibrosis arising from polycythemia vera (PV) and essential thrombocythemia (ET) are challenging clinical entities and many patients have a very poor prognosis. For the most part, treatment is palliative and often of limited efficacy. Allogeneic hematopoietic cell transplants (HCT) can effectively control the disease, and reduced intensity conditioning regimens have reduced regimen related complications. However, many studies have excluded patients older than age 65 (or even 60) years. This is problematic as the median age at diagnosis is approximately 67. We retrospectively evaluated a cohort of 26 patients age ≥ 60 years with PMF or post PV or ET myelofibrosis who underwent allogeneic HCT between 1999 and 2007. The median age was 63 (range 60–75) years; 9 of these patients were older than 65 (range 66–75) years. Donors were HLA-matched siblings (n=14) or unrelated (n=12). Conditioning regimens included Fludarabine (Flu)/2 Gy TBI (n=16), Flu/Campath(Cam)/TBI (n=2), Flu/Melphalan/ATG (n=2), Cam/Flu/CD45Mab/4.5 Gy TBI (n=2), Flu/Busulfan (Bu) (n=2), Flu/Bu/ATG (n=1), Flu/Mel/Cam (n=1). The median follow up for the cohort was 200 (range 17 – 1322) days. Eleven of 26 patients were alive at the date of last followup, and 9 were relapse free. The median follow up for living patients was 251 (range 100 – 1322) days. Of the 15 patients who had died, 5 died of disease progression and the remaining 10 of non-relapse causes: infection (n=4), GVHD (n=2), respiratory failure (n=2), multi-organ failure (n=1), dissecting aneurysm (n=1). At last follow up, 4 of 9 patients age >65 were alive a median of 374 (range 132 – 896) days without disease relapse. Five of the nine patients died, 4 from non-relapse causes and one with disease progression. In summary, reduced intensity conditioning and allogeneic transplantation in patients with myelofibrosis more than 60 years of age resulted in relapse-free survival of 40–45%. While the mortality rate was high, the success rate was remarkable in view of the patient age and the frequent presence of co-morbid conditions. We suggest, therefore, that ongoing and future clinical trials of allogeneic HCT for myelofibrosis should allow enrollment of older patients.

We previously reported 2-year overall survival (OS) of 65% among 33 pts with MCL given nonmyeloablative HCT (Blood2004; 104: 3535). Here, we update our results on the initial 33 pts with median follow up of 63 months and report on 20 additional pts with emphasis on: long-term disease control and resolution of chronic GVHD. Pts were conditioned with 2Gy TBI with or without fludarabine (90 mg/m2). Median age for all pts was 56 (range 33–75) years and median number of prior regimens was 4. Forty percent of pts had failed high-dose autologous HCT and an additional 11% had planned autologous HCT before allograft (4 pts had refractory disease and 2 were in PR). Comorbidity scores of ≥3 were found among 40% of pts. Forty percent of pts were not in CR/PR at HCT and 26% and 21% had marrow infiltration and lymph node size ≥5 cm, respectively. Donors were related (n=28) or unrelated (n=25). After HCT, incidences of grades II, III, and IV acute GVHD were 25%, 13%, and 9% respectively, and chronic extensive GVHD was 53%. Complete (CR) and partial remissions (PR) were seen in 71% and 3% of pts with measurable disease at HCT, respectively. Estimated 5-year rates of non-relapse mortality (NRM), progression/relapse, OS, and progression-free survival (PFS) were 27%, 22%, 58%, and 52%, respectively (Table 1). Among 19 pts in CR at HCT, 11 are alive and in CR, 7 died in CR, and one relapsed (now in CR after Rituximab and donor lymphocyte infusion). Among 13 in PR at HCT, 10 achieved CR and are alive, one died in PR, and 2 died from relapse. Among 21 pts with refractory/relapsed disease at HCT, 12 achieved CR and are alive, 2 have stable disease and are alive, and 7 relapsed (2 are alive in CR and PR after further treatment). At 5-years, 44% and 14% were alive without or with chronic GVHD requiring immunosuppression (Figure); and median duration of treatment for chronic GVHD was 33 months. Outcomes were comparable among related and unrelated recipients. Relapse rates were 47% vs. 14% among pts with vs. without LN size of ≥5 cm (p=0.02) and NRM was 41% vs.17% (p=0.05) among pts with HCT-CI scores of ≥3 vs. 0–2, respectively. Nonmyeloablative HCT is a potentially curative therapeutic modality for pts with advanced MCL, including patients who were chemotherapy-refractory, with a median PFS beyond 5 years. Sustained remissions and continuing resolution of chronic GVHD were observed with extended follow up. Pts with bulky LN might benefit from further debulking strategies before HCT. Table: Outcomes by donor type Donor Related (n = 28) Unrelated (n = 25) % % Grades III–IV non-hematological toxicities 39/18 38/26 Acute GVHD, grades II/ III/ IV 22/14/7 28/12/12 Chronic GVHD 50 55 CR 73 67 5-year NRM 26 28 5-year Progression/relapse 22 21 5-year PFS 53 51 5-year OS 59 56 5-year Pts alive with chronic GVHD requiring immunosuppression 14 7 Figure Figure

The number of adult CBTs is increasing. However, delayed engraftment and immune reconstitution remain important issues in CBT frequently resulting in significant resource utilization. To evaluate the relative cost of adult CBT, waiver of consent was obtained from the IRB, and we compared costs of all adult CBTs (n=25) performed at our center since February 2006 (when our current CBT protocols opened) to cohorts of adult unrelated (URD) (n=88) transplants performed during the same period. Twelve patients, median age 30 (range 20–42), underwent myeloablative CBT following conditioning with 120 mg/kg cyclophosphamide (CY), 75 mg/m2 fludarabine (FLU), and 13.2 Gy total body irradiation (TBI) and were compared to 51 consecutive URD( n=27 matched URD (MURD) and n=24 mismatched (MMURD)) patients, median age 44 (range 20–67), undergoing transplant on our center’s standard myeloablative treatment plan with either CY/TBI or busulfan (BU)/CY conditioning. Thirteen patients, median age 55 (range 24–68), underwent CBT following reduced intensity conditioning (RIC) with 200mg/m2 FLU, 50mg/kg CY, 2 Gy TBI, +/− 90 mg/kg anti-thymocyte globulin (ATG) and were compared to 37 URD (n=20 matched URD (MURD) and n=17 mismatched (MMURD)) patients, median age 56 (range 22−75) undergoing non-myeloablative RIC with 90 mg/m2 FLU/2 Gy TBI (an outpatient regimen). Ten additional patients undergoing tandem autologous/non-myeloablative URD transplant for multiple myeloma and 4 additional patients undergoing non-myeloablative URD transplant for primary graft failure were excluded. Administrative cost data were obtained for the following functional areas: inpatient bed, laboratory, pharmacy (outpatient prescriptions and home infusions excluded), outpatient clinic, radiology, radiation oncology, infusion, endoscopy, surgery, and other. Only charge data was available for the supplies functional area (which includes blood bank services), and these data were included in the analysis as charges rather than costs. Costs were totaled from arrival date on the center’s transplant service to date of discharge to primary providers or date of death. Thirteen patients were found to have relapsed disease upon arrival on the transplant service and underwent induction chemotherapy prior to transplant; these costs were excluded. Costs of cord blood units and unrelated donor products were excluded. Results are presented in Table 1. Results include cost breakdown by all functional areas with median CBT cost greater than $10,000. Myeloablative CBT was more expensive than myeloablative MURD transplant (p=0.003) and trended toward more expensive than MMURD transplant (p=0.097). RIC CBT was more expensive than both MURD and MMURD non-myeloablative RIC transplant (p=0.0002 and 0.024 respectively). Cost comparisons were performed using the Wilcoxon-Mann-Whitney test. The increased costs of CBT reflect the increased supportive care required by CBT patients; CBT patients required more inpatient days (except versus MMURD myeloablative transplants), required more laboratory testing, required more costly in-hospital and outpatient clinic drug administration, and needed more frequent transfusions. Strategies to decrease time to engraftment, to enhance immune reconstitution, and to further decrease the intensity of RIC regimens may result in significant CBT cost reductions. Table 1: CBT vs URD transplant: Cost comparison

We retrospectively assessed 1) overall platelet (PLT) and red blood cell (RBC) transfusion requirements within the first 100 days after allogeneic among HCT recipients given either nonmyeloablative (n=365) or myeloablative conditioning (n=1430); 2) transfusion requirements among nonmyeloablative recipients given grafts from related (n=187) vs. unrelated donors (n=178), and grafts from ABO matched (n=203) vs. ABO mismatched donors (n=159); and 3) the impact of ABO incompatibility on HCT outcomes among nonmyeloablative recipients. Table 1 summarizes results. We confirmed that myeloablative recipients were more likely to receive both PLT and RBC transfusions than nonmyeloablative recipients (both p

We analyzed data from 38 patients (median age = 56, range: 8 – 68 years) with acute leukemia (n=15), chronic idiopathic myelofibrosis (n=6), myelodysplastic syndrome with or without myeloproliferative disorder (n=5), chronic myeloid leukemia (n=4), non- Hodgkin lymphoma (n=4), aplastic anemia (n=2), multiple myeloma (n=1) and renal cell carcinoma (n=1), who underwent salvage allogeneic hematopoietic cell transplantation (HCT) for allograft failure. In 14 cases the original donors were used for second HCT, while in 24 cases different donors were identified (Table 1). Conditioning regimens for first HCTs included total body irradiation (TBI; 2 Gy) with or without fludarabine (Flu; n=28), myeloablative regimens (busulfan-cyclophosphamide, n=6; cyclophosphamide-TBI, n=2); and other, cyclophosphamide-anti-thymocyte globulin-based regimens (n=3). Conditioning for salvage HCT consisted of Flu 30 mg/m2/day on days -4 to -2 followed by TBI of 3 (n=24) or 4 (n=14) Gy on day 0. Cyclosporine and mycophenolate mofetil were used for postgrafting immunosuppression. The median time between first and salvage HCTs was 91 (range, 29 to 1004) days. Sustained second grafts were achieved in 34 patients (89%), while grafts failed in 4 patients (11%), all of whom had idiopathic myelofibrosis. With a median follow-up among surviving patients of 2.0 (range, 0.3 to 7.8) years, the 2 and 4 year Kaplan-Meier survival estimates were 49% (95% CI: 31%, 66%) and 42% (95% CI: 23%, 61%), respectively. The 2 year relapse-rate and non-relapse mortality were 36% (95% CI: 20%, 52%) and 25% (95% CI: 11%, 41%), respectively. The cumulative incidences of grades 2–4 acute and moderate-severe chronic graft-versus-host disease (GVHD) at 2 years were 42% and 41%, respectively. Four patients with chronic GVHD discontinued systemic immunosuppressive therapy at a median of 2.5 years. Within the limitations of the small patient numbers studied, TBI dose (3 vs. 4 Gy), same vs. different donors for salvage HCT, donor type (related, unrelated, HLA-haploidentical related vs. double umbilical cord), and HCT comorbidity scores did not appear to affect outcomes. Based on this retrospective multicenter analysis, we conclude that graft failure following allogeneic HCT can be effectively overcome by second transplantation using conditioning with Flu and low dose TBI (3 or 4 Gy), which should be further investigated in a prospective manner. Table 1. Donors in 1st and 2nd HCTs. HLA-MURD: HLA-matched unrelated donor; HLA-MMURD: HLA-mismatched unrelated donor, UCB: umbilical cord blood. | | 2nd HCT | |:---------------------:| ---------- | --------------- | | | | Different Donor | | 1st HCT | Same Donor | HLA-MURD | HLA-MMURD | Double UCB | HLA-haploidentical | | HLA-identical sibling | 11 | 11 | - | - | - | - | | HLA-MURD | 17 | 3 | 10 | 4 | - | - | | HLA-MMURD | 8 | - | 1 | 7 | - | - | | Double UCB | 2 | - | - | - | 1 | 1

Median ages of pts with most hematological malignancies are beyond 60 years. The advent of nonmyeloablative conditioning regimens has extended the use of allogeneic HCT to these older pts. Here, we retrospectively investigated outcomes among 280 pts aged ≥60 years, given HCT between 1998 and 2006. Results were broken down in 3 age groups 60–64 (n=166), 65–69 (n=90), and ≥70 (n=24) years old, respectively. Pts aged ≥70 years had less preceding chemotherapy, less often failed autologous HCT, more often had related grafts, and had higher comorbidity scores compared to pts in the other two age groups (table 1). Acute leukemias were more frequent and lymphoma/multiple myeloma were less frequent among pts aged ≥70 years old, resulting in higher risk for relapse (Table 1). After HCT, non-relapse mortality, relapse, and progression free survivals at 5-years for all pts were 26%, 41%, and 32% respectively. Five-year Kaplan Meier rate of overall survival was 35%, of those 12% vs. 23% were with vs. without chronic GVHD requiring immunosuppressive therapy, respectively. There were no statistically significant differences in outcomes among the three age groups except for more infections and days of hospitalization among pts aged 65–69 years compared to the other two age groups (Table 2). In multivariate analyses of risk factors, high HCT-comorbidity index (1–2 and ≥3) independently predicted higher NRM (HR: 2.84 and 3.0, respectively, p=0.01) and, not surprisingly, previously defined high relapse risk predicted relapse (HR: 2.17, p=0.06); both predicted worse OS (p=0.005 and p=0.0009, respectively) and PFS (p=0.01 and p=0.02, respectively). Pts given unrelated grafts did as well as recipients of related grafts. In conclusion, nonmyeloablative allogeneic HCT can be curative among pts older than 60 years with resolution of chronic GVHD among a majority of pts. Comorbidities and relapse risk rather than age should be used for benefit-risk assessment. Continued enrollment of elderly pts in prospective studies including unrelated donors is warranted. Table 1: Pt characteristics Age groups, years (60–64) (n=166) (65–69) (n=90) (70–74) (n=24) Median Interval from Dx to HCT, months 19 15 8 Median (range) # of prior regimens 3 (0–14) 3 (0–13) 2 (0–10) Median CD34+ cell number x 106/kg 6.7 6.7 6.5 Median CD3+ cell number x 108/kg 2.9 3.1 3.4 % Prior radiotherapy 18 11 13 Prior HCT Failed 19 12 4 Planned 8 6 4 Positive patient CMV sero-status 58 65 79 HLA-matched related 54 53 83 Donor HLA-matched unrelated 41 44 17 HLA-mismatched unrelated 5 3 0 Conditioning 2 Gy TBI 12 13 21 2 Gy TBI + FLU 88 87 79 HCT-CI scores 0 27 27 15 1–2 30 39 25 3–4 30 17 40 ≥5 13 17 20 Diagnoses Acute leukemia 35 47 62 Chronic leukemia 15 13 13 Lymphoma/myeloma 21 23 8 Myelodysplastic/myeloproliferative 16 16 17 Others 3 1 0 Disease status at HCT CR 46 41 38 PR 15 30 21 Refractory 28 21 33 Relapse 11 8 8 Relapse risk Low 19 17 8 Standard 48 51 38 High 33 32 54 Table 2: Outcomes per age groups HCT Outcomes Age groups, years P* (60–64) (n=166) (65–69) (n=90) (70–74) (n=24) FUO indicates fever of unknown origin *Test for trend μBased on hazard ratio analysis Bacterial 1.4 2.3 1.7 .0004 Rates of Infection episodes per person Viral 0.7 1.1 0.7 NS within 100 days FUO 0.3 0.4 0.1 NS Fungal 0.3 0.2 0.3 NS Median (range) days of hospitalization 1 (0–60) 4.5 (0–179) 0.5 (0–47) NS % Acute GVHD Grades II–IV 52 49 54 NSμ Grades III–IV 16 12 13 NSμ Chronic extensive GVHD 39 45 54 0.05μ NCI-CTC criteria grades III–IV non-hematological toxicities 42 57 50 NSμ Pts with Full donor chimerism at 1-year CD3/CD33/BM 68/ 84/ 80 66/ 83/ 77 67/ 79/ 71 NSμ CR at 2-years 40 47 63 NSμ 5-years Relapse/progression 38 46 46 NSμ 5-years NRM 28 22 29 NSμ 5-years OS 37 36 23 NSμ 5-years PFS 34 31 25 NSμ Patients alive and off all immunosuppression 24 25 5 NSμ

Studies of simultaneous transplantation of two cord blood units have suggested that as compared to single unit cord blood transplantation (CBT), increased cell dose may overcome graft rejection and improve survival, particularly in mismatched CBT, as well as enhance the graft-versus-malignancy effect. Successful double CBT has been reported following both myeloablative and reduced intensity (RIT) conditioning. However, several concerns remain, including the possibility of increased incidence of GVHD compared to single unit CBT, as well as persistent delays in hematopoietic recovery and immune reconstitution despite the increase in cell dose achieved by double CBT. We have used an algorithm to guide selection of units in our most recent cohort of CBT patients (pts), such that single unit CBT is allowed only for units matched for 5/6 HLA with total nucleated cell (TNC) dose of at least 4.0 ×107/kg or matched for 6/6 HLA with TNC at least 3.0 ×107/kg. Between February 2006 and June 2007, 22 pts underwent CBT for high risk hematologic malignancies (21 in complete morphologic remission, 8 with minimal residual disease, 1 with active mycosis fungoides). Fourteen pts median age 20.5 years (range 0.6–42) underwent myeloablative transplantation following conditioning with fludarabine (FLU) 75mg/m2, cyclophosphamide (CY) 120mg/kg, and total body irradiation (TBI) 13.2 GY. Eight pts median age 52.5 years (range 24–68) underwent RIT following FLU 200mg/m2, CY 50mg/kg, and TBI 2 GY with the addition of ATG 90mg/kg if there was no exposure to chemotherapy in the three months preceding transplant. GVHD prophylaxis was cyclosporine and MMF. Donor-recipient matching based on intermediate resolution for HLA-A and B and high resolution for HLA-DRB1 was as follows: single 5/6 unit for three pts (14%), two units 4/6 for 12 pts (55%), two units 5/6 for three pts (14%), one 4/6 and one 5/6 unit for three pts (14%), and two units 6/6 for one patient (5%). All double CBT units were at least 4/6 matched to each other. At a median follow-up of 243 days among surviving pts (range 71–451), overall survival (OS) is 77% (17/22). OS is 93% (13/14) among pts treated with myeloablative conditioning and 50% (4/8) among RIT pts. 14% (3/22) of pts have relapsed. Day 100 transplant related mortality (TRM) is 5% (1/22). Incidence of grade II–IV and III–IV aGVHD in 19 of 22 pts who had sustained engraftment and survived past day 30 are 89% (17/19) and 26% (5/19) respectively. Three pts are non-evaluable due to septic death prior to engraftment, early relapse, and graft failure. 100% (11/11) of pts seropositive for CMV prior to transplant developed CMV reactivation measured by PCR at a median of 22 days (range 3–39). No (0/11) seronegative pts developed CMV. There was one case of non-fatal CMV pneumonitis. Using this strategy, we have observed limited early TRM and a lower than expected incidence of relapse in a high-risk population. We have seen a higher incidence of a GVHD than reported at other centers, and long term monitoring for chronic GVHD will be important. Though we have observed few significant infectious complications, all seropositive patients reactivated CMV early post-transplant, emphasizing the need for close monitoring of CMV reactivation and improved treatment strategies. Ongoing experience will confirm the efficacy of our algorithm for the use of two CB units for all 4/6 HLA matched units and low dose 5/6 and 6/6 units.

BACKGROUND: Chronic GVHD is a major determinant of quality of life after allogeneic HCT. Systemic immunosuppressants (IS) are the mainstay of treatment for cGVHD. Patients (pts) with cGVHD after myeloablative HCT are able to discontinue IS at a median of 23 months after HCT (Stewart et al., Blood 2004 Dec 1;104[12]:3501–6). We examined the duration of treatment with IS in patients with cGVHD after non-myeloablative HCT. METHODS: All pts who underwent non-myeloablative HCT at our institutions through 31 Dec 2003 were assessed for inclusion. Two hundred sixty-nine pts were alive and free of their underlying disease at day +84 after HCT; 138 of these (51%) began systemic IS for cGVHD, at a median of 112 days after HCT. We analyzed these 138 pts with cGVHD to determine duration of treatment with IS. Diagnoses are listed in Table 1. Sixty-eight pts received related allografts and 70 received unrelated allografts; median age at HCT was 53.3 years. The allograft source was granulocyte colony-stimulating factor-mobilized peripheral blood mononuclear cells (G-PBMC) in 137 pts and bone marrow in 1 pt. Relapsed malignancy and death were considered competing risk events in the estimation of cumulative incidence of discontinuation of IS; follow-up was censored at the time of death, relapsed malignancy, or discontinuation of all systemic IS. RESULTS: Thirty-seven pts (27%) had recurrent malignancy and 23/138 (16%) died without recurrent malignancy while on IS; 41/138 (30%) discontinued all systemic IS after resolution of cGVHD; and 37/138 (27%) were alive without malignancy at last follow-up (median 3.7 years after cGVHD diagnosis), but remained on IS for cGVHD. Five-year cumulative incidence estimates by outcome are listed in Table 2. Of pts alive and free of malignancy at 5 years after cGVHD diagnosis, 58% had discontinued IS. In pts who discontinued IS, the median time to discontinuation was 2.0 (range, 0.3 – 5.7) years (see Figure). CONCLUSION: The median time to resolution of cGVHD and discontinuation of IS in this group is comparable to that reported after myeloablative HCT (24 months vs. 23 months), despite the older age of these pts (median age 53.3 years, vs. 39.5 years in myeloablative cohort) and the prevalence of G-PBMC allografts (>99%, vs. 20% in myeloablative cohort). In this older population with cGVHD after non-myeloablative allogeneic HCT, the majority of pts who remain alive and free of relapsed malignancy have resolution of cGVHD over time. Table 1 . Underlying diagnoses among pts with cGVHD Diagnosis No. of pts (%) AML 19 (14%) ALL 6 (4%) CML 6 (4%) CLL 11 (8%) MDS 14 (10%) HD 9 (6%) NHL 31 (22%) MM 32 (23%) MPD 1 ( Waldenstrom's 1 ( Renal cell carcinoma 1 ( Wilms' tumor 1 ( Immunodeficiency syndrome 6 (4%) Total 138 Table 2 . Five-year cumulative incidences Outcome 5-year cumulative incidence % (95% CI) Relapsed malignancy/death 45 (36–54) Alive, malignancy-free, on IS 23 (15–33) Alive, malignancy-free, discontinued IS 32 (23–41) Download : Download high-res image (142KB) Download : Download full-size image Figure

Use of HLA-mismatched unrelated donors after myeloablative conditioning is an effective treatment of blood disorders when HLA-matched donors are not available. However, the feasibility of HLA-mismatched HCT following nonmyeloablative conditioning is not well established. We previously demonstrated in over 1200 patients (pts) that a nonmyeloablative conditioning regimen consisting of 2 Gy TBI and fludarabine (90 mg/m2) followed by post-grafting immunosuppression with MMF/CSP was an effective approach for HCT from 10/10 HLA-matched donors. Here we report the results of a clinical trial aimed at determining whether stable hematopoietic grafts from HLA-class I mismatched donors could be safely established after nonmyeloablative conditioning. Pts were conditioned with fludarabine and 2 Gy TBI, followed by extended immunosuppression with CSP (day −3 to +180; tapered by +365) and MMF (tid days 0 to +100; tapered by +150). 46 pts ineligible for myeloablative conditioning were enrolled on this multi-institutional study through April/07. 36 unrelated and 3 related donor-recipient pairs were mismatched in both the HVG and GVH vectors. 43 unrelated pairs were mismatched for at least one antigen (AG) (15 at HLA-A, 5 at HLA-B, 22 at HLA-C) except one pt who had two allele mismatches (HLA-A and B). All 3 related pairs were mismatched for one HLA-A AG. 13 pts, in addition to the AG mismatch, had an allelic mismatch (3 at HLA-A, 4 at HLA-B, 6 at HLA-C). All pts were matched for HLA-DRB1 and HLA-DQB1 at the allele level. Diagnoses included NHL (n=17), HD (n=5), AML (n=11), ALL (n=5), CLL (n=3), MM (n=4) and MDS/AML (n=1). The median age of pts was 56 (range 13–69) years and median time from diagnosis to HCT was 32 (range 5–205) months. Disease status at time of HCT included CR (n=23), PR (n=11), stable disease (n=2), and refractory relapse (n=10). Before HCT, pts had received a median of 7 (range 2–15) courses of therapy. 43% had failed myeloablative HCT (autologous n=18; allogeneic n=2). All pts received G-CSF mobilized PBSC containing median doses of 7.3 ×106 CD34 and 2.4 × 108 CD3 cells /kg. 12 pts were not evaluable for the graft rejection outcome (3 early death, 7 mismatched in GVH vector only, 2 tandem auto-allo). The remaining pts showed median percentages of donor peripheral blood T cell, granulocyte and marrow chimerism of 100% at all time points (on days 28, 56, and 84). Two pts experienced graft rejection but had a successful 2nd HCT from the same or an alternative donor. 35 of the 46 pts developed acute GVHD (2 grade I, 21 grade II, 5 grade III, 7 grade IV) and 15 developed chronic GVHD. At 2 years, the cumulative probabilities of relapse/progression and non-relapse mortality were 30% and 45%, respectively. The 2 year Kaplan-Meier estimates of OS and PFS were 27% and 25%. This study demonstrates that nonmyeloablative conditioning using fludarabine and low-dose TBI can be successfully used for grafts from pts with HLA- class I mismatched donors.

Background. The “true” nonmyeloablative allogeneic stem cell transplantation (NM-HCT) allows initial establishment of mixed T-cell chimerism for up to 6 months. The prolonged presence of host memory immune response after NM-HCT may play a role in protection against CMV infection especially early after NM-HCT. Furthermore, we previously reported that the incidence and poor outcome of ganciclovir-related neutropenia (GCV-N) is strongly associated with myelotoxic conditioning. Therefore, non-myeloablative HCT may also contribute to a lower risk of GCV-N. In this to date largest cohort we examined the risk of CMV infection and GCV-N after NM conditioning. Methods. We retrospectively analyzed 537 NM-HCT recipients (median age 54.2 yrs) and 2489 M-HCT recipients (median age 39.8 yrs) transplanted between 1/1995 and 12/2005. The conditionings for NM-HCT mostly consisted of 2 Gy TBI with/without fludarabine. Post-grafting immunosuppression consisted of most commonly mycophenolate mofetil and cyclosporine (CSP) for NM-HCT recipients and methotrexate/CSP for M-HCT recipients. CMV surveillance was performed weekly by antigenemia (AG) or plasma PCR testing. GCV/VGCV was given for CMV AG/PCR positivity. We evaluatedany AG/DNA detection by day 100,AG >10/200,000 PBL or PCR> 1000 copies/ml (high-grade CMV AG/DNA) by day 100 andGCV-N defined as non-relapse-related neutropenia (ANC1000 μL at time of viremia using multivariable Cox regression.In addition, post-engraftment neutropenia, defined as ANC Results. There was no significant difference in the incidence of CMV AG/DNA at any level between NM-HCT and M-HCT (39% vs.37%, HR 1.1, P=0.42). However, there was less high-grade CMV infection in NM-HCT compared to M-HCT patients (9% vs. 14%, adj. HR 0.6, P < 0.01). Risk factors for high-grade CMV infection other than M-HCT were advanced recipient age, CMV serostatus, transplantation year and acute GVHD. The incidence of GCV-N was similar between NM-HCT and M-HCT recipients (28% vs. 20%, adj. HR 1.3, P=0.27). Risk factors for GCV-N were advanced recipient age and acute GVHD. On the other hand, the incidence of post-engraftment neutropenia was higher in NM-HCT (29% vs. 13%, adj. HR 2.1, P Conclusion. Our results suggest that the risk of CMV reactivation is not affected by NM conditioning but that progression to higher levels of viral load is reduced. This may be due to residual host memory immunity after NM-HCT. Despite less toxic conditioning, the incidence of GCV-N in NM-HCT was similar to that in M-HCT. Notably, the incidence of post-engraftment neutropenia was more frequent in NM-HCT compared to M-HCT recipients. This may be due to higher recipient and/or donor age, lower capacity to metabolize drugs, or the use of myelotoxic co-medication such as MMF or TMP-SMX.

BACKGROUND: Nonmyeloablative allogeneic hematopoietic cell transplantation (HCT) as consolidation following high dose therapy with autologous HCT is a promising treatment for MM. Low early transplant mortality and high response rates were described in small patient (pts) cohorts with limited follow-up (FU). Here we report on the outcome of pts with HLA-identical siblings treated with this tandem auto/allo approach after a median FU of 5 year. PATIENTS: Pts with stage II-III MM (n=102) were treated with tandem auto/nonmyeloablative allografting at 8 centers between August 1998 and August 2005. Median age was 55(range 32–71) years. Median number of prior treatments was 1(1–2), and median number of prior cycles of treatment was 6 (2–18). Median time between initiation of treatment and autografting was 13(2–118) months and 73/102 (72%) pts initiated their tandem HCT within 10 months of initial therapy. Median time between auto and allo HCT was 80(40–281) days. Autologous HCT conditioning was with melphalan 200 mg/m2 and allogeneic conditioning with 2Gy total body irradiation (TBI) alone (n=75, 73%) or with 2Gy TBI plus fludarabine 90 mg/m2 (n=27, 23%). Post allografting immunosuppression was with mycophenolate mofetil (MMF) and cyclosporine (n=91, 89%) or MMF and tacrolimus (n=11, 11%). Sixty-seven pts (66%) had chemoresponsive disease and 35 (34%) were refractory. The disease status at allo HCT included complete remission (CR, 29 pts, 28%), partial remission (PR, 38 pts, 37%), refractory (RD, 27pts, 26%) or progressive disease (PD, 8pts, 8%). RESULTS: 101/102 pts had sustained donor engrafment. Forty one (41%) and 8 pts (8%) experienced grade 2 to 4 and 3 to 4 acute graft-versus-host-disease (GVHD); 70 pts (69%) had extensive chronic GVHD. Median FU post-allografting was 5(0.75–8.66) years. The overall response rate was 94%, with 64 (63%) and 32 pts (31%) achieving CR and PR respectively. Median time to progression was 4 years. Median progression-free survival (PFS) was 3 years while 5-year estimated PFS was 35%. Median overall survival (OS) has not been reached. Three and 5-year estimated OS were 75% and 63% respectively. Cumulative incidence of nonrelapse mortality (NRM) at 100 days, 1 and 5 year were 1%, 13% and 19% respectively. Most of the NRM (89%) was related to GVHD and/or infection. In the subset of 73 pts who initiated their tandem HCT within 10 months from initial therapy, the estimated OS and PFS at 3 and 5-years were 80% and 55%, 69% and 40% respectively. In univariate analysis refractory or progressive disease at allo HCT was associated with higher risk of relapse (p=0.004) and relapse plus NRM (p CONCLUSION: Long-term disease control and GVHD and its complications remain key issues to address following tandem auto/nonmyeloablative allogeneic HCT. Comparison with tandem autologous HCT awaits results of the BMT-CTN 0102 and similar trials.

Background: The potential role of donor NK cells after nonmyeloablative conditioning for allogeneic hematopoietic cell transplantation (HCT) is not defined. We investigated the impact of the kinetics of donor NK cell engraftment as well as the impact of missing recipient KIR ligands and the number of donor inhibitory and activating KIR genes on HCT outcomes in 282 patients (153 with HLA-matched related donors and 129 with unrelated donors) conditioned with 2 Gy TBI +/− fludarabine. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. Diagnoses were hematological malignancies (n=274) or solid tumors (8). Methods: NK cells were isolated from peripheral blood by flow cytometry on days 14, 28 and 42 after HCT. The proportions of cells of donor and host origin were assessed by FISH or by VNTR-PCR. High-resolution HLA-typing was performed using oligonucleotide probe and/or direct sequencing methods. Donor KIR genotyping was performed using a commercial PCR-SSP kit (Invitrogen) following manufacturers protocol. Results: High numbers of T (P=0.01) and CD34+ (P=0.009) cells in the graft, as well as lower numbers of donor inhibitory KIR genes (P=0.01) were each associated with higher levels of donor NK cell chimerism. There was a suggestion of an association between lower numbers of activating KIR genes and higher CD56 chimerism, however this was not statistically significant. NK cell chimerism levels were comparable in patients who had all KIR ligands present vs. in those who were missing any ligand, and there was no association between the specific missing ligand and NK chimerism. A day-14 NK cell chimerism level of < 50% was associated with increased risks of graft rejection (P=.009). Modeling chimerism levels as a continuous linear variable, there was no association between NK cell chimerism levels on day 14 and occurrence of grade II-IV acute GVHD. In contrast, high levels of donor NK cell chimerism on days 14–42 were associated with a lower risk of relapse (P=0.006) and better progression-free survival (P=0.003) in time-dependent analyses. The qualitative associations between donor NK cell chimerism and graft rejection, GVHD, relapse or progression-free survival did not change after adjustment for the presence of recipient KIR ligands nor after adjustment for the number of donor inhibitory or activating KIR genes. Finally, the 3-year cumulative incidence of relapse was 42% in patients who have all ligand for donor NK cell KIR, versus 38% in patients who miss one or more ligand for donor NK cell KIR (adjusted hazard ratio = 1.05; 95% confidence interval 0.65–1.68; p=0.85). Conclusions: Robust engraftment of donor NK cells correlated with low risk of graft rejection, low risk of relapse and high progression-free survival but not with acute GVHD. The clinical importance of donor KIR inhibitory and activating genes on post-transplant donor NK chimerism merits further study.

An HCT-comorbidity index (HCT-CI) was modeled to capture comorbidities and predict outcomes among pts given allogeneic HCT (Blood 2005). Here, we asked whether the HCT-CI could provide prognostic information among pts given autologous HCT. We retrospectively collected and analyzed comorbidities and other pretransplant variables among 273 pts with lymphoma transplanted between 2000 and 2005. Pts were conditioned with cyclophosphamide + total body irradiation or radio-labeled monoclonal antibody (n=127), busulfan/melphalan/thiotepa (n=86), melphalan/cytarabine/BCNU/etoposide (n=37), or other regimens (n=17). Diagnoses were indolent (n=36) or aggressive non-Hodgkin lymphoma (n=169) and Hodgkin lymphoma (n=68). At HCT, 16%, 37%, and 34% of pts had disease transformed from follicular lymphoma, chemosensitive disease, and elevated LDH, respectively. Median age was 49 (range:13–76) years. Median number of prior regimens was 3 and 58% and 26% had prior rituximab and radiotherapy, respectively. HCT-CI comorbidities (score >0, Table 1) were found among 65% of pts, of whom 16% had score 1, 19% score 2, 26% scores 3–4, and 4% scores ≥5. Among pts with scores ≥3 (n=82), 20 had a single comorbidity while 62 had ≥2 comorbidities. In univariate analyses, number of prior regimens, prior rituximab, prior radiotherapy, histology, transformed disease, conditioning regimen, CD34+ cell dose, and time between diagnosis and HCT were not statistically significant in predicting outcomes. Factors which were significant in univariate analyses, were tested in multivariate models (Table 2), where HCT-CI scores independently predicted non-relapse mortality (NRM) and together with LDH and chemosensitive disease predicted overall (OS) and relapse-free survivals (RFS). Pts with HCT-CI scores of 0 vs 1–2 vs ≥3 had 2-year NRM of 3%, 8%, and 19% and OS of 80%, 78%, and 52% respectively (Figure). Further, pts with scores of 3–4 vs ≥5 had NRM and OS of 15% and 57% vs 42% and 25%, respectively. In conclusion, Pts with HCT-CI scores of 0 and 1–2 tolerated high-dose conditioning equally well, while scores ≥3 were associated with increasing mortality. The HCT-CI is an informative tool to assess pts given autologous HCT, and it could provide valuable independent prognostic information when used prospectively. | | | % | Score | |:----------------:| ---------- | --- | ----- | | Pulmonary | Moderate | 30 | 2 | | | Severe | 9 | 3 | | Cardiac | EF ≤ 50% | 7.3 | 1 | | | Arrhythmia | 2.9 | 1 | | | CAD | 1.8 | 1 | | | Valvular | 0.7 | 3 | | Hepatic | Mild | 6.6 | 1 | | | Moderate | 1 | 3 | | Prior malignancy | 5.5 | 3 | | Ulcer | 2.6 | 2 | | Rheumatologic | 1 | 2 | | Renal | 0.4 | 2 | | Diabetes | 4.8 | 1 | | Psychiatric | 14 | 1 | | Infection | 3.7 | 1 | | Obesity | 8.8 | 1 | | Others | 1.8 | 1 | Table 1: HCT-CI Comorbidities | | | NRM | Mortality | RFS | |:-------------------------------------------------------:| -------- | --- | --------- | --- | ------- | | | | HR | P | HR | P | HR | P | | *Age was included but was not statistically significabt | | HCT-CI scores | | 1 | | 1 | | 1 | | | | 1–2 | 1.6 | 0.5 | 1.1 | 0.8 | 1.1 | 0.6 | | | ≥ 3 | 6.6 | 0.0009 | 2.9

Our group has previously shown that DLI was ineffective for converting 90% elicited successful GVT effects (Blood2004;103:790). To facilitate effectiveness of DLI for patients (pts) with low or declining donor CD3 chimerism, a multicenter trial assessing the safety and efficacy of adding pentostatin was developed. Pts receiving HLA-matched NM HCTs and at risk for rejection, defined as low ( Kinetics of CD3 Chimerism Post-DLI Kinetics of CD3 Chimerism Post-DLI

Background. We investigated the impact of graft composition on GVHD in 1520 allogeneic transplant recipients given PBSC. Methods. Graft composition was determined by FACS analyses and expressed as cells/kg of recipient weight. Cell types were defined as follows: CD3+ T cell (CD3+CD56−), CD4+ T cell (CD3+CD4+), CD8+ T cell (CD3+CD8+), natural killer (NK) cell (CD3−CD56+), NK/T cell (CD3+CD56+), B cell (CD20+), monocyte (CD14+), and CD34+ cells (CD34+CD14−). Cell doses were modeled as continuous linear variables or by quartiles. Cox (for chronic) and logistic (for acute) regression models were adjusted for conditioning regimen intensity, pt age, female donor to male recipient vs. other gender combination, and disease risk. Results. The median age among all pts was 52 (45 among myeloablative, 57 among nonmyeloablative); 27% of pts were male transplanted from a female donor; 66% of pts had high-risk disease; 49% were transplanted from an alternative donor (47% unrelated, 2% mismatched sibling); 51% received a nonmyeloablative conditioning. Table 1 shows graft composition and GVHD incidences according to donor type and conditioning intensity. There were no statistically significant associations between cell dose and acute GVHD, although there was a suggestion that the association of NK/T cell was dependent on conditioning. In particular, increasing NK/T cells were associated with an increased probability of grades 2–4 GVHD among myeloablative pts (p=.03) but not among nonmyeloablative pts. There were no statistically significant associations between cell dose and chronic GVHD, but several cell types showed evidence of an interaction between donor and cell dose. In particular, increasing B cells and CD3+, CD4+, and CD8+ T cells were associated with an increased risk of chronic GVHD among pts with an HLA-identical donor (p=.006, p=.0003, p=.0002, p=.02, respectively) while the associations among alternative donors were in the opposite direction and were not statistically significant (p=.68, p=.26, p=.44, and p=.15, respectively). Lack of correlation in the alternative donor group may reflect differences in T-cell responses to the greater minor histocompatability divergence, or changes in T-cell functionality associated with the dose of G-CSF (higher in sibling donors) used for mobilization. Increasing CD34+ cells was not statistically associated with chronic GVHD in either myeloablative (negative association, p=.10) or nonmyeloablative (positive association, p=.11) pts. Conclusions. Higher numbers of transplanted T and B cells were associated with an increased risk of extensive chronic GVHD in pts given grafts from HLA-identical siblings. Increasing CD34+ cells were not associated with a statistically significant increase in chronic GVHD. Further analyses looking at other clinical outcomes such as survival are forthcoming. | | Nonmyeloablative conditioning and HLA-id sibling | Myeloablative conditioning and HLA-id sibling | Nonmyeloablative conditioning and alternative donor | Myeloablative conditioning and alternative donor | |:---------------------------------------------- | ------------------------------------------------ | --------------------------------------------- | --------------------------------------------------- | ------------------------------------------------ | | Median # of T cell transplanted (× 108/Kg) | 3.4 | 2.5 | 2.5 | 2.8 | | Median # of CD34+ cell transplanted (× 106/Kg) | 8.6 | 7.5 | 6.9 | 7.5 | | Incidence of grade II–IV acute GVHD (%) | 47 | 66 | 61 | 81 | | Incidence of extensive chronic GVHD (%) | 40 | 54 | 41 | 49 | Table 1. Graft composition and GVHD according to conditioning intensity and donor type

We previously reported 2-year overall survival (OS) of 60% among 64 pts given nonmyeloablative HCT (Sorror et al, JCO2005, 23: 3819). Here, we update our results on the initial 64 pts with median follow up of 5 (range:3–7) years and report on 18 additional pts with emphasis on: 1) long-term disease control, 2) resolution of chronic GVHD, and 3) outcomes of pts with poor-risk genomic features. Conditioning consisted of 2 Gy total body irradiation with or without fludarabine (90 mg/m2). Median age was 56 (range 42–72) years and median number of prior regimens was 4. Eighty-seven percent, 56%, and 41% of pts had fludarabine-refractory CLL, chemo-resistant disease at HCT, and unfavorable cytogenetics, respectively. Donors were related (n=52) or unrelated (n=30). The incidences of grades II, III, and IV acute GVHD were 39%, 14%, and 2% respectively, and chronic extensive GVHD was 51%. Overall disease response was seen in 70% of pts, and 55% achieved complete remission (CR). Estimated 5-years rates of non-relapse mortality (NRM), progression/relapse, OS, and progression-free survival (PFS) were 23%, 38%, 50%, and 39%, respectively (Table 1 shows outcomes by donor type). Overall, 42 patients are alive; 31 in CR, 4 in PR, 1 with stable disease, and 6 with relapse/progression. Among 14 responding pts tested and found to have molecular eradication of their disease, 2 died of NRM, 2 eventually relapsed, and 10 remained negative at a median of 6 years. Lymph node diameter >5 cm was an independent risk factor for relapse (p=0.008) and PFS (p=0.01), while unfavorable cytogenetics (Table 2) were not (p=0.65 and 0.88, respectively). Among the pts who were alive at 5-years, 76% were without chronic GVHD while 24% received immunosuppression for chronic GVHD. Median performance status (PS) was 100% and 90% among pts without or with chronic GVHD, respectively. Nonmyeloablative HCT resulted in a median survival of 5 years for fludarabine-refractory CLL. Sustained molecular remissions and continuing resolution of chronic GVHD with good PS were observed in most pts with extended follow up. Nonmyeloablative HCT might change the natural history of CLL with unfavorable cytogenetics if considered earlier. Table 1: Outcomes by donor type Donor At 5-years Related (n=52) Unrelated (n=30) p-value % % CR 48 67 0.04 NRM 22 24 0.97 Pgrossion/relapse 43 26 0.18 PFS 35 51 0.28 OS 49 51 0.57 Pts alive with chronic GVHD requiring immunosuppression 14 7 Table 2: Outcomes of pts with poor genomic features Abnormality (n) Pts alive Pts who died Median interval, years Median interval, years CR/PR/PD From Dx From HCT CR/PR/NE/PD From Dx From HCT PR indicates partial remission; PD, progression; Dx, diagnosis; and NE, not evaluated del 17p (7) 4/0/0 6.5 3.3 1/0/0/2 6.5 0.3 del 11q (7) 1/2/2 8.1 2.1 1/0/0/1 7.5 0.7 Tri 12 (7) 4/0/0 6.7 4.4 0/0/2/1 3.8 0.2 Complex (9) 4/0/0 11.4 5.7 0/1/0/4 10.5 3.5

In a preclinical canine model using major histocompatibility (MHC)-haploidentical littermate peripheral blood stem cell (PBSC) grafts, initial donor chimerism could be achieved after a nonmyeloablative conditioning regimen consisting of monoclonal antibody S5 (anti-CD44) from days −7 to −2, 200 cGy TBI on day 0, and MMF and cyclosporine for postgrafting immunosuppression. However, sustainable donor chimerisms could not be achieved in many of these dogs, with 25 of 44 (57%) rejecting their grafts at a median of 7 weeks after transplant. In order to improve the engraftment rate, a novel strategy to overcome the immunological barrier created by this MHC-haploidentical setting was developed. By adding single, progressively higher doses of MTX on day+3 after transplantation to the above regimen, we hoped to control host T and NK cells, both of which contribute to graft rejection in MHC-haploidentical HCT, and to target alloreactive donor T cells which are responsible for graft-versus-host disease (GVHD). Once dose toxicity is established, this system will also allow the study of transplants using gene-modified, MTX-resistant CD34 selected PBSC, which can provide additional intrinsic graft protection on exposure to MTX. To date, 11 dogs have been transplanted using the above regimen and adding either 50 (n=5), 100 (n=3), or 200 (n=3) mg/m2 MTX on day +3 followed by leucovorin rescue on days +4 and +5. Early results showed that 4 of 5 dogs experienced graft rejection in the MTX50 group, 0 of 3 dogs rejected in MTX100 (p=0.047, Monte Carlo), and all 3 dogs in MTX200 have continued to exhibit stable mixed chimerisms from +42 to +76 days after transplant. Dogs in all 3 cohorts had rapid engraftment within 1 week, with similar average peak mononuclear cell (MNC) chimerisms at comparable timepoints (83% at 5 wks, 88% at 6 wks, and 80% at 5 wks at MTX50, 100, and 200 respectively). None of the 11 dogs have shown evidence of GVHD or MTX toxicity, and all dogs cleared MTX within 48 hours. All dogs exhibited early donor tolerance on mixed lymphocyte culture assays within 2 weeks and preserved NK activity posttransplant. While these data are preliminary, adding single, progressively larger doses of MTX on day +3 to a novel, nonmyeloablative conditioning regimen appeared to improve engraftment among MHC-haploidentical canine recipients with no signs of GVHD. There was high initial donor chimerism without undue early toxicity. Further, this study will aid in our establishment of high-dose, posttransplant MTX as a way of promoting sustained donor chimerism after transplanting CD34 selected, MTX-resistant canine PBSC in the MHC-haploidentical setting. This preclinical data serve as a basis for developing nonmyeloablative transplant options for patients without HLA-identical donors.

Recurrence of high risk hematologic malignancy after allogeneic hematopoietic cell transplantation (HCT) indicates the persistence of malignant cells that are resistant to the conditioning regimen given before HCT and the immunologic effects of donor cells after HCT. Early recurrence of high-risk hematologic malignancy after myeloablative conditioning is associated with a very poor prognosis. Given the minimal exposure to cytotoxic therapy during and the lower burden of regimen-related toxicity after nonmyeloablative preparative regimens, we hypothesized that relapse-directed interventions would be more effective for patients with high-risk malignancy after HCT with nonmyeloablative conditioning compared to myeloablative conditioning. We retrospectively analyzed outcomes among 195 patients treated for acute leukemia (AML, n=123; ALL, n=28), chronic myeloid leukemia beyond accelerated phase (n=21), or high-risk myelodysplastic syndromes (n=23) that recurred after HCT with myeloablative or nonmyeloablative conditioning between 1995 and 2004. Relapse-directed interventions included withdrawal of immunosuppression (WIS), chemotherapy, and donor lymphocyte infusion (DLI) used singly or in combination as allowed by clinical circumstances. Interventions were used for 68% and 87% of patients who had recurrence < 100 days after HCT with myeloablative or nonmyeloablative conditioning, respectively, and for 83% and 95% of those who had recurrence ≥ 100 days after HCT. The incidence rates of life-threatening GVHD and remission were 6% and 25% among patients with myeloablative conditioning, compared to 19% and 26% among those with nonmyeloablative conditioning (Table 1). The incidence of remission was higher among patients who had recurrence ≥ 100 days after HCT as compared to < 100 days after HCT (p = 0.04). Contrary to our hypothesis, interventions were not more effective among patients with nonmyeloablative conditioning compared to myeloablative conditioning, as measured by remission rates (Table 1) or survival. The 2-year survival rates among patients with recurrence < 100 days after HCT were 4% and 0% among patients who had myeloablative and nonmyeloablative conditioning regimens, respectively. The corresponding 2-year survival rates among patients with recurrence ≥ 100 days after HCT were 12% and 5%. In summary, with either myeloablative or nonmyeloablative conditioning regimens, limited clinical benefit is gained from the interventions typically used for management of early recurrent high-risk hematologic malignancy after HCT. Thus, innovative and more effective strategies are needed for treatment of recurrent high-risk malignancy after allogeneic HCT. Interventions and outcomes among patients treated for recurrent high-risk hematologic malignancy after allogeneic HCT Total WIS Chemo DLI GVHD* CR *GVHD, life-threatening graft-versus-host disease; CR, complete remission. **Recurrence was detected at 100–200 days from HCT in 9 cases and >200 days in 11 cases. Myeloablative conditioning Recurrence < Day 100, n (%) 87 78 51 11 6 16 (90) (59) (13) (7) (18) Recurrence ≥ Day 100–200, n (%) 65 50 55 13 3 21 (77) (85) (20) (5) (32) Non-myeloablative conditioning Recurrence < Day 100, n (%) 23 18 13 5 5 5 (78) (57) (22) (22) (22) Recurrence ≥ Day 100, n (%)** 20 13 15 2 3 6 (65) (75) (10) (15) (30)

NM-HCT from related donors who share at least one HLA haplotype with the recipient is a treatment option for patients with hematologic malignancies who do not have suitable HLA-matched related or unrelated donors. We have shown that addition of cyclophosphamide pre-transplant (29 mg/kg) and post-transplant (50 mg/kg on day+3 or days+3 and +4) to a standard nonmyeloablative conditioning regimen of fludarabine and TBI combined with tacrolimus and MMF prophylaxis of GvHD is an effective means of achieving complete engraftment of donor T-cells and granulocytes with low non-relapse mortality and an incidence and severity of acute and chronic GvHD which does not differ from studies of NM-HCT using HLA-matched donors. In a study of 89 patients (FHCRC,N=30; JH,N=59) with advanced myeloid and lymphoid malignancies, patients with relapsed HL had significantly better survival than patients with other diagnoses. Fifteen patients with HL were studied (median follow-up of 17 mo). Patients were heavily pre-treated with a median number of prior cytotoxic therapy regimens of 5 (range: 3–10); 14 patients had failed prior autologous HCT with a median time of 18 mo from auto-HCT to NM-HCT. Donors for 9 patients were HLA-mismatched at ≥4/10 loci. All evaluable patients were complete donor CD3 and CD33 chimeras by day +28 (one patient died on day +28 and was not evaluable). Clinically significant acute GvHD occurred in 9/14 (64%) patients and Grades III/IV GvHD in 3/14 (21%) patients. Extensive chronic GvHD occurred in 5/14 (36%) patients. Two patients (13%) died of non-relapse causes at days +236 and +633 secondary to chronic GvHD. Median failure-free survival (FFS) was 21 mo compared to 6 mo for patients with other lymphoid malignancies (N=23) or myeloid malignancies [(N=51), see Figure]. The hazard of mortality was less among patients with HL compared to those with other lymphoid malignancies [hazard ratio (HR)=0.36 (p=0.05)] yet patients with myeloid malignancies had a similar hazard of mortality compared to those with lymphoid malignancies other than HL [HR=0.88 (p=0.66)]. Difference in FFS between HL and other lymphoid malignancies was not statistically significant [HR=0.54 (p=0.16)], nor was the difference between myeloid and other lymphoid malignancies [HR=1.26 (p=0.44)]. More patients will need to be studied to better demonstrate a graft-versus-lymphoma effect of haploidentical transplantation in relapsed HL. NM-HCT from haploidentical donors may be a good option for such patients who have a limited window of opportunity to proceed to transplant if responsive to salvage chemotherapy. Download : Download high-res image (95KB) Download : Download full-size image Download : Download high-res image (79KB) Download : Download full-size image

NM-HCT makes use of graft-versus-tumor effects and has been applied to treat pts with hematological malignancies who were ineligible for conventional myeloablative (M)-HCT. The current study retrospectively analyzed platelet and RBC transfusion requirements within the first 100 days after HCT in 365 consecutive pts given NM- HCT from HLA-matched related (MRD; n=187) or unrelated donors (URD; n=178) between December 1997 and January 2005. Diagnoses included NHL and HD (29.5%), MM (19.4%), acute leukemias (20%), chronic leukemias (14.8%) and others (16.3%). Pts’ age ranged from 9 months to 74.5 (median 50.1) years. We also asked whether ABO incompatibility increased transfusion requirements in NM recipients, and whether there were differences in transfusion requirements between related and unrelated recipients within the subgroup of ABO-mismatched recipients. Further, overall transfusion requirements were compared to those among 1430 concurrent HLA-matched recipients given M-HCT. Among NM recipients, a higher percentage of unrelated recipients required transfusions than of related recipients (48% vs.25% for platelets p Transfusion requirements during first 100 days after HCT % of pts requiring platelets transfusions Daily units (Median) p % of pts requiring RBC transfusions Daily units (Median) p Conditioning Nonmyeloablative 36 0 77 0.052 Myeloablative 99 0.420

While toxicities and transplant related mortality (TRM) have limited the use of conventional allogeneic HCT to younger patients (pts) without significant medical comorbidities, WM is a disease that affects primarily older pts with a median age of 63 years at diagnosis. Here we examined the safety and efficacy of nonmyeloablative (NM) HCT for patients with refractory WM, where anti-tumor effects are provided by graft-versus-tumor immune responses rather than from conditioning therapy. Twelve pts with refractory WM were treated within the institutions of the Seattle Consortium using HLA-matched related donor (n=7) or unrelated donor (URD) (n=5) HCT. NM conditioning consisted of 2 Gy TBI with (n=8) or without (n=4) fludarabine (30 mg/m2/day x 3 days). Eleven pts received unmodified G-CSF-mobilized peripheral blood mononuclear cells, and 1 pt received URD bone marrow. Post-grafting immunosuppression consisted of mycophenolate mofetil and either cyclosporine or tacrolimus. The median age was 58 (range 44–65) years and median time from diagnosis to allogeneic HCT was 6.6 (range 1.5–20) years. Pts had received a median of 4.5 (2–8) prior regimens. The median follow-up after HCT was 14 (range 1–85) months overall, and median follow-up for surviving pts (n=7) was 17 (range 4–85) months. All pts except 1 have stably engrafted with >95% donor CD3+ T cell chimerism. Acute GVHD grades II, III, IV, and extensive chronic GVHD occurred in 50%, 8%, 0%, and 58% of pts, respectively. TRM was 17%. Responses (4 CR and 6 PR) were seen in 10 of 11 (91%) evaluable pts while 1 had progressive disease. The non-evaluable pt died from early non-relapse causes. The median time to CR was 12 (6–32) months for the 4 CR pts, and 1 of the PR patients still has a declining IgM at 10 months. Only 1 of the 10 responders has had WM progression, though 1 pt in CR died from relapsed diffuse large B-cell lymphoma (DLBCL) 16 months after allografting despite no longer having a monoclonal IgM spike. This pt had been allografted in tandem following an auto transplant with BEAM conditioning for transformation of WM to DLBCL. Of the 7 sibling transplants, all had a response (3 CR and 4 PR). Of 5 pts receiving URD allografts, 1 had a CR, 2 had a PR, 1 was not evaluable due to TRM on day 29, and 1 pt failed to respond and died of progressive IgM myeloma 12 months after HCT. One pt with a PR had heavily pretreated disease (pancytopenic pre-HCT) and died of host-derived AML 10 months after HCT. The Kaplan-Meier estimates of 5 year overall and progression free survival were 59% and 61%, respectively. In summary, graft-versus-tumor effects that develop slowly following NM allogeneic HCT have been observed in the majority of pts with refractory WM. These graft-versus-WM effects occurred in the absence of serious GVHD and with low TRM. NM allogeneic HCT provides a new treatment option for WM pts and may result in long-term disease control. Figure Figure

Sixty-two patients (pts) with chemotherapy-refractory indolent or transformed NHL were treated at 10 centers with allogeneic HCT from related (n=34) and unrelated (n=28) donors after 2 Gy total body irradiation with or without fludarabine. Diagnoses included follicular lymphoma (FL) (n=54, including 10 with grade 3 FL), small lymphocytic lymphoma (n=6), and marginal zone lymphoma (n=2). Median age was 54 years (range 33–66 years), and median time from diagnosis to HCT was 4.4 years (range 0.5–18.5 years). Sixteen pts had histologically documented transformation to diffuse aggressive lymphoma prior to HCT. Twenty-seven pts (44%) had failed autologous HCT. Disease status at the time of HCT was complete response (CR, n=16), partial response (PR, n=22), refractory (n=13), untested relapse (n=9), or unknown (n=2). Eleven of the 28 unrelated donor/recipient pairs (39%) had HLA mismatches: 2 at a single allele, 7 at a single antigen, and 2 at an antigen and an allele. One pt had non-fatal graft rejection from a 1-antigen-mismatched unrelated donor. Median follow-up of survivors after HCT was 36.6 months (range 2.3–60 months). Responses (CR [n=18] and PR [n=7]) were seen in 25 of 44 (57%) pts with evaluable disease prior to HCT, while 5 had stable disease, 9 progressed, and 5 were not evaluable due to early non-relapse mortality (NRM) on d27–d108. Two of 16 pts (13%) transplanted in CR relapsed; one was treated with donor lymphocyte infusion and achieved a persistent CR. The incidences of acute GVHD grades II–IV, III–IV, and chronic GVHD were 63%, 19%, and 53%, respectively. At 3 years, the risks of relapse/progression and NRM were 19% and 42%, respectively. There was a trend toward increased mortality with unrelated donors (HR 1.87 [0.9–3.7, p=0.08]). Progression-free and overall survival (PFS and OS) were significantly better in the non-transformed group (see tables 1 and 2). | | Non-transformed | Transformed | |:---------- | --------------- | ----------- | | Relapse | 6/46 (13%) | 6/16 (38%) | | NRM | 20/46 (43%) | 6/16 (38%) | | 3-year OS | 24/46 (52%) | 4/16 (25%) | | 3-year PFS | 20/46 (43%) | 4/16 (25%) | Table 1. Outcomes | | HR (95% CI) | p | |:----------------------:| -------------- | ---- | | All-cause Mortality | 2.39 (1.2–4.9) | 0.02 | | Relapse/progression | 4.75 (1.5–15) | 0.01 | | Grade 3+ acute GVHD | 1.84 (0.5–6.3) | 0.35 | | Extensive chronic GVHD | 1.96 (0.8–5.0) | 0.18 | Table 2. Hazard Ratios (HR) for Transformed vs. Non-Transformed Pts ![Figure][1] Figure Allogeneic HCT after non-myeloablative conditioning can produce durable responses and prolonged survival in pts with refractory indolent or transformed NHL. Pts transplanted before histologic transformation had significantly better outcomes. Future efforts will focus on reducing NRM and identifying optimal timing of HCT. [1]: pending:yes

Background. We previously reported data from 103 pts receiving PBSC from HLA-matched unrelated donors after conditioning with 2 Gy total body irradiation (TBI) plus 90 mg/m2 fludarabine. Postgrafting immunosuppression included MMF (administered from day 0 until day +40 with taper through day +96), and CSP (given from day -3 to day +100, with taper through day 180) (historical group). The incidences of grade III–IV acute and chronic extensive GVHD were 14% and 48%, respectively. Several studies have suggested that CSP could prevent activation-induced cell death of T-cells, and thus potentially delay the eradication of donor-versus-host alloreactive T-cells, preventing tolerance induction. Conversely, antimetabolite inhibitors, such as MMF, could delete alloreactive T-cells by induction of activation-induced cell death and apoptosis, and thus might favor tolerance induction Pts and Methods. Here, we investigated whether postgrafting immunosuppression with prolonged MMF (given at 15 mg/kg orally thrice a day from day 0 to day +30, then at 15 mg/kg orally twice a day until day 150, and then tapered at day 150 and discontinued at day 180) and truncated CSP (abruptly discontinued on day 80), would promote tolerance induction and reduce the incidence of GVHD (current protocol, n=71) after unrelated HCT with nonmyeloablative conditioning. Results. Sustained donor engraftment was achieved in 68 pts (96%) in the current protocol, versus in 98 pts (95%) in the historical group. Grades II, III and IV acute GVHD were seen in 36 (50.7%), 11 (15.5%) and 7 (9.9%) pts, respectively, in the current protocol, versus 39 (37.9%), 11 (10.7%) and 4 (3.9%) pts, respectively, in the historical group. The incidences of grade II–IV and grade III–IV acute GVHD were 75% and 23% in the current protocol, versus 52% (P=.05) and 14% (P=.14) in the historical group. The 1-yr incidence of chronic GVHD was 46% in the current protocol, versus 48% in the historical group. Finally, the 1-yr probabilities of relapse, nonrelapse mortality and progression-free survival were 24%, 36% and 40%, respectively, in the current protocol, versus 26% (P=.9), 18% (P=.005) and 56% (P=.04) in the historical group. The increased incidence of nonrelapse mortality in the current protocol was not due only to the increased incidence of grade II–IV acute GVHD, since nonrelapse mortality remained significantly higher in the current protocol than in the historical group after adjusting for occurrence of grade II and grade III–IV acute GVHD (P=.04). Evaluation of pretransplant comorbidities is ongoing. Conclusions. Postgrafting immunosuppression with prolonged MMF and truncated CSP failed to decrease the incidence of GVHD after nonmyeloablative conditioning with URD. Ongoing efforts are directed at reducing the risk of acute GVHD after nonmyeloablative conditioning for unrelated donors by replacing tacrolimus for CSP, and by adding sirolimus to MMF and CSP.

Reduced intensity allogeneic transplantation offers a potentially curative option to NHL patients with chemorefractory disease or relapse following autologous transplant. The efficacy of this approach relies on the development of a graft-vs-lymphoma (GVL) effect by establishment of donor chimerism. GVL, however, is most effective for NHL in settings of stable, chemoresponsive, and non-bulky disease. Anti-CD20 radioimmunotherapy (RIT) has been shown to be safe and effective in the treatment of B-NHL. This phase II clinical trial was designed to evaluate the safety and efficacy of administering 90Y-Ibritumomab Tiuxetan (Zevalin, Biogen-Idec) as part of reduced intensity allogeneic stem cell transplantation in order to safely provide disease control prior to the establishment of a GVL-effect that could maintain the remissions. Fourteen patients with relapsed or refractory CD20+ NHL and evaluable disease, who had too high-risk lymphoma for a routine non-ablative transplant and were not eligible for a traditional myeloablative transplant were treated with 0.4 mCi/kg 90Y-Ibritumomab Tiuxetan (maximum 32 mCi) on day −14, followed by fludarabine (30mg/m2 on days −7 to −5), 2 Gy TBI on day 0, and HLA-matched related (n=8) or unrelated (n=6) allogeneic PBSC transplantation. Cyclosporine and mycophenolate mofetil were employed for graft-vs-host disease (GVHD) prophylaxis. Patient characteristics included: median age=57y (range 33–69y), median # of prior regimens=6 (range 3–12), prior autologous transplant=5 (36%), chemoresistant=100%, median tumor bulk=3.7cm, elevated LDH=5 (36%), baseline cytopenia (ANC25% marrow involvement with NHL=5 (ranging from 30–85% NHL involvement). Histologies included: mantle cell=5, diffuse large B-cell=4, follicular=3, small lymphocytic=1, hairy cell=1. There have been no non-relapse-related deaths in the first 100 days, no graft rejections or failures, and all patients achieved >80% donor CD3/CD33 chimerism by 28 days after transplant. No patients developed ≥ grade 3 acute GVHD, though 7 experienced grade 2 GVHD. Three patients died following progressive NHL and 2 died after day 100 from GVHD and infection-related complications. The median platelet and neutrophil nadirs were 9×103/μL and 50/μL, respectively. Responses to date include 3 complete responses (CR), and 4 partial responses (PR), including 1 CR, 6 PR, 3 stable disease by 1 month after transplant. With a median follow up of surviving patients of 6 months (range

We developed a new HCT-specific comorbidity index (HCT-CI) as a sensitive tool to capture pretransplant comorbidities among pts given allogeneic HCT (Sorror et al. Blood. 2005; 106, 2912–2919). Here, we retrospectively analyzed whether the HCT-CI was useful in assessing how pts with B cell malignancies tolerated NM vs M-HCT. Results among consecutive pts (n=125) given NM-conditioning with 2Gy total body irradiation (TBI) (19%) or 2 Gy TBI combined with 90 mg/kg of fludarabine (81%) were compared to those among concurrent M-pts (n=55) conditioned with cyclophosphamide plus busulfan (15%) or 12Gy TBI (85%). Diagnoses were non-Hodgkin lymphoma (NHL, 80% vs 52%), Hodgkin disease (HD, 5% vs 20%), and chronic lymphocytic leukemia (CLL, 15% vs 28%), respectively. At HCT, NM-pts differed substantially from M-pts with respect to age (median 52 vs 40 years,), prior treatment regimens (median 5 vs 3), prior failed high-dose HCT (45% vs 9%), unrelated donors (43% vs 18%), and G-PBMC as stem cell source (99% vs 78%). Smaller differences existed for disease chemo-sensitivity (58% vs 69%) and aggressive disease (56% vs 64%). HCT-CI scores >0 were found among 70% and 58% of NM and M-pts, respectively. After HCT, 2-year NRM and survival were 26% and 59% vs 29% and 51% among NM and M-pts, respectively. There were no statistically significant differences in NRM (19% vs 4%, p =0.3) and survival (70% vs 70%, p =0.7) between NM and M-pts with HCT-CI scores of 0; however, this comparison was limited by the small numbers of non-relapse deaths. NM-pts with HCT-CI scores of ≥ 1 had statistically significantly lower NRM (29% vs 47%, HR=0.50, p =0.03, Figure) and better survival (54% vs 37%, HR=0.60 p =0.05) compared to M-pts. These differences remained after adjusting for pretransplant differences (NRM, HR=0.3, p =0.006; survival, HR=0.33, p =0.002). In a further analysis which included all pts, increasing HCT-CI scores and M-conditioning were important risk factors for NRM and survival (Table). We concluded that pts with B cell malignancies and HCT-CI scores of ≥1 tolerated NM-HCT better than M-HCT, and prospective randomized trials may be warranted to confirm this result. Additional data are needed to clarify possible differences between M and NM-conditioning for patients without comorbidities. | | | NRM | Survival | |:------------------------------------------------------------------------------------------------------------------------------------------------ | ------ | ---- | -------- | ---- | | | | HR | p | HR | p | | *Lower HR means better survival. Other risk factors, including donor type; CMV sero-status; and disease chemo-sensitivity, were not significant. | | Conditioning | NM | 1.0 | | 1.0 | | | | M | 3.03 | 0.007 | 2.27 | 0.006 | | HCT-CI scores | | 1.0 | | 1.0 | | | | 1–2 | 2.56 | | 1.78 | | | | ≥3 | 3.85 | 0.001 | 2.44 | 0.005 | | Diagnoses | NHL | 1.0 | | 1.0 | | | | HD | 0.79 | | 0.98 | | | | CLL | 0.55 | 0.3 | 0.46 | 0.03 | | Graft | G-PBMC | 1.0 | | 1.0 | | | | Marrow | 0.23 | 0.03 | 0.38 | 0.03 | | Age, years

An HCT-specific comorbidity index (HCT-CI) was developed to capture comorbidities among patients (pt) given HCT. Here, we asked whether HCT-CI could provide information independent from current measures, notably PS. PS before and toxicities after HCT were prospectively graded per Karnofsky and Common Toxicity Criteria, respectively, while comorbidities were retrospectively evaluated per HCT-CI. Spearman rank was used to evaluate correlations. This study included pts (n=107) diagnosed with hematologic malignancies and conditioned with nonmyeloablative regimen of 2 Gy total body irradiation alone (15%) or with 90 mg/kg of fludarabine (85%) before related (44%) or unrelated HCT (56%). There were no exclusion criteria for HCT-CI scores but pts with PS of Table 1: Impacts of HCT-CI and PS scores on 1-year HCT outcomes HCT-CI scores PS scores 0–2 ≥3 p >80% ≤80% p % % Grades II-IV GVHD 43 67 0.01 48 62 0.02 Grades III-IV toxicities 25 53 0.004 30 52 0.02 Grade IV toxicities 8 23 0.03 12 20 0.2 NRM 11 30 0.01 20 22 0.5 survival 84 50 0.0006 68 64 0.2 Table 2: Composite index of HCT-CI and PS scores Groups Grades II-IV GVHD Grades III-IV toxicities Grade IV toxicities % A HCT-CI=0–2 and PS=≥80% 37 20 6 B HCT-CI=0–2 and PS=

Regression of metatstatic renal cell carcinoma (RCC) has been observed in 8–57% of patients undergoing nonmyeloablative allogeneic hematopoietic cell transplant (HCT) from HLA-matched donors. Tumor regression in this setting typically occurs after complete donor T cell engraftment is established, and is correlated with the development of GVHD. We previously isolated from two patients experiencing regression of metastatic RCC after nonmyeloablative allogeneic HCT CD8+ CTL clones that recognized a RCC-associated minor histocompatibility (H) antigen presented by HLA-A*0201, and localized the gene encoding this antigen to chromosome 19q. To identify the gene that encodes this antigen, a cDNA expression library made from a HLA-A*0201+ minor H antigen-positive tumor cell line was screened using a transfection assay in COS-7 cells. After two rounds of screening, a 1.4 kb cDNA was identified that stimulated HLA-A*0201-dependent cytokine release from minor H antigen-specific CTL. Sequencing showed that this cDNA was derived from the MGC13170 gene on chromosome 19q, within the region of significant linkage. Sequencing of MGC13170 alleles in minor H antigen-positive and minor H antigen-negative cells revealed six single nucleotide polymorphisms (SNPs), inherited as a haplotype and all previously identified, that determined susceptibility or resistance to lysis by minor H antigen-specific CTL. Analysis of 5′ and 3′ truncation constructs derived from the MGC13170 cDNA identified an interval encoding a 48-residue open reading frame that contained the epitope and spanned one of the six SNPs (dbSNP rs3745526) that had been shown to correlate with CTL recognition. Further analysis of minigenes spanning this nonsynonymous T↔A SNP identified an interval containing T at the polymorphic position and encoding a predicted 11-residue peptide that stimulated maximal HLA-A2-dependent cytokine release from minor H antigen-specific CTL. The T↔A SNP is predicted to create a Ser↔Thr polymorphism in the encoded peptide. A synthetic 11-mer peptide containing Ser at the polymorphic residue, but not the homologous peptide containing Thr at this position, was recognized by minor H antigen-specific CTL when pulsed onto minor H antigen-negative HLA-A*0201+ cells, thus demonstrating that the T allele of MGC13170 encodes the minor H antigenic peptide. The function of MGC13170 is unknown, but a previous study (Zhou et al., Ai Zheng21:341–345, 2002) suggested a role in resistance of tumor cells to chemotherapeutic agents. The range of tissues in which the epitope-encoding MGC13170 sequence is expressed was evaluated in silico by probing the translated human EST database with the predicted sequence of the 48-residue polypeptide encoded by the epitope-containing ORF. Of the several hundred ESTs identified that encoded the Ser- or Thr-containing peptide sequence, 72% were derived from tumor cells or cell lines (including RCC), 5% from embryonic or fetal tissues, 9% from embryonic stem cells, and 11% from normal tissues. Thus, MGC13170 encodes a novel HLA-A*0201-restricted minor H antigen that is expressed in a wide variety of neoplastic, embryonic, and fetal cells. Further studies of MGC13170 as a possible target for antitumor immune responses after allogeneic HCT are underway.

We developed a new HCT-specific comorbidity index (HCT-CI) as a sensitive tool to capture pretransplant comorbidties among pts given allogeneic HCT (Sorror et al, online, 2005; DOI 10.1182/blood-2005-05-2004). In the current report, we used the HCT-CI to explore differences in the tolerability of nonablative compared to ablative HCT in MDS or AML pts with pretransplant comorbidities. Consecutive pts (n=88) receiving nonablative conditioning with 2 Gy total body irradiation (TBI) alone (6%) or with 90 mg/kg of fludarabine (94%) were compared to concurrent pts (n=361) conditioned with cyclophosphamide plus busulfan (70%) or 12–14 Gy TBI (30%). All pts were classified into low (AML-first complete remission or MDS-refractory anemia) and high-risk disease (all others). Overall, 76% of nonablative pts had AML compared to 66% of ablative pts. At HCT, nonablative pts differed substantially from ablative pts with respect to age (median 60 vs 46 years), use of unrelated donor grafts (57% vs 42%), use of marrow grafts (5% vs 20%), and HCT-CI scores of ≥2 (75% vs 45%). Smaller differences existed for high-risk disease (64% vs 58%) and pt cytomegalovirus positive sero-status (59% vs 55%). Proportional hazards models were used to estimate the hazard ratio (HR) for non-relapse mortality (NRM) and survival for pts receiving nonablative compared to ablative conditioning regimens; these models were adjusted for stem cell source, pt age, donor type, pt cytomegalovirus sero-status, diagnoses (MDS vs AML), and HCT-CI scores (Table). Adjusted HRs were not statistically significantly different, except among pts with high-risk disease and HCT-CI scores of ≥2 where nonablative pts had lower HR for NRM (0.34, P =0.005) and worse survival (0.51, P =0.006, Fig.1). These results suggest that pts with high-risk MDS or AML and HCT-CI scores of ≥2 might have less NRM and better survival with nonablative than with ablative HCT. Prospective randomized trials are warranted to confirm this retrospective observation. Additional data are needed for AML and MDS pts with low comorbidities or low disease risk in order to clarify the usefulness of nonmyeloablative conditioning. | | Nonablative/ablative | NRM | Survival | |:----------------------------------------------------------------------------------:| -------------------- | --------------- | -------- | -------------- | | | Number | HR* (95% CI) | P | HR* (95% CI) | P | | *HR

Nonmyeloablative hematopoietic cell transplantation (NMHCT) has become an immunotherapeutic option for patients with a variety of malignant diseases. The susceptibility to malignancy-eradicating graft-versus-tumor effects, however, appears to depend on type and stage of the underlying diseases. Thus, the aim of this study was to estimate relapse risk after NMHCT according to pretransplant disease characteristics. Between 1997 and 2004, 595 consecutive patients (median age, 55; range, 5–74 years) received related (n=383) or unrelated (n=212) grafts after preparation with total body irradiation (TBI, 200 cGy, n=168) alone, or in combination with fludarabine (90 mg/m2, n=423). The relapse rate per person year (PY) at risk, which corrected for variation in follow-up time and the competing risk of non-relapse mortality, was calculated for 27 different disease and stage categories. No corrections were made for graft rejections, all of which resulted in relapse. The overall relapse rate per PY was 0.37. As shown in Table 1, patients with chronic lymphocytic leukemia, low-grade Non-Hodgkin lymphoma (NHL) and multiple myeloma had the lowest relapse rates per PY (0.00, 0.09, 0.09; “low-risk”). In contrast, patients with advanced myeloid diseases had a relapse risk per PY of >0.50 (“high-risk”). The increased incidence of graft rejection among patients with chronic myeloid leukemia and myelodysplastic syndrome, however, may have contributed to the higher relapse risk observed in this group. Patients with lymphoproliferative diseases not in remission (Hodgkin disease and high-grade NHL excluded), and myeloid malignancies in remission at transplant had relapse rates per PY of 0.20 – 0.50 (“standard-risk”). For patients deemed at “high risk” for relapse after NMHCT, intensification of the preparative regimens, and/or cytoreductive strategies before or after transplant need to be considered in the design of future transplant protocols. Relapse Risk Categories Low Risk (n) Relapse Rates per PY Standard Risk (n) Relapse Rates per PY High Risk (n) Relapse Rates per PY CLL, chronic lymphocytic leukemia; MM, multiple myeloma; MDS, myelodysplastic syndrome; AML, acute myeloid leukemia; CML, chronic myeloid leukemia; ALL acute lymphocytic leukemia; CMML, chronic myelomonocytic leukemia; CR, complete remission; CP/AP/BP, chronic-/accelerated-/blast-phase. CLL, CR (4) 0.00 Waldenstrom′s (7) 0.23 high-grade NHL, no CR (18) 0.61 MM, CR (23) 0.09 MM, no CR (109) 0.26 Hodgkin, CR (7) 0.67 low-grade NHL, CR (22) 0.09 CLL, no CR (52) 0.28 Hodgkin, no CR (26) 0.83 low-grade NHL, no CR (49) 0.19 Myelofibrosis (5) 0.28 MDS (RAEB/RAEB-t, 16) 0.51 MDS (RA/RARS, 18) 0.29 MDS, previous chemo (17) 0.65 AML > CR1 (31) 0.30 AML, no CR (10) 0.69 High-grade NHL, CR (16) 0.31 AML, antecedent MDS (31) 0.94 CML, CP1 (27) 0.34 CMML (7) 0.74 AML, CR1 (43) 0.42 CML, CP2 (7) 1.05 ALL, CR1 (9) 0.45 CML, AP/BP (11) 1.05 ALL, > CR1 (7) 0.88 ALL, no CR (4) 1.08

The poor survival of elderly patients with advanced AML or high-risk MDS following conventional chemotherapy, as well as their poor tolerance for high-dose regimens used in conventional myeloablative hematopoietic cell transplantation (HCT) demands innovative therapeutic approaches. Recent success achieving stable donor chimerism following infusion of allogeneic peripheral blood stem cells (PBSC) after reduced intensity (non-myeloablative) conditioning regimens affords an opportunity to safely induce a graft-vs-leukemia (GVL) effect with minimal acute morbidity. GVL effects, however, appear to be most potent in patients with low tumor burdens at the time of transplantation. We have therefore conducted a Phase I clinical trial of targeted hematopoietic irradiation delivered by an 131I-labeled anti-CD45 antibody (BC8) to determine the feasibility, safety and efficacy of this approach toward reducing the burden of disease before an established non-myeloablative regimen. In this dose escalation study designed to estimate the maximum tolerated dose of 131I-BC8 antibody that can be combined with fludarabine (FLU) and low dose total body irradiation (TBI), 33 patients over 50 years of age with advanced AML or high-risk MDS (> 5% blasts) were treated with 246 to 932 mCi 131I delivering an estimated 5.2 to 45.9 (mean 27.5) Gy to bone marrow, 17.3 to 155 (mean 81.2) Gy to spleen, and 12–24 Gy to the liver (dose-limiting organ). Patients then received FLU (30 mg/m2 daily for 3 days), 2 Gy TBI, and HLA-matched related (n = 10) or unrelated (n = 23) PBSC grafts with graft-vs-host disease prophylaxis provided by cyclosporine and mycophenolate mofetil. The median age of patients was 61 (50–71) years. Twenty-four patients had AML, with 6 (13%) patients in second or third complete remission, 2 (4%) with primary refractory disease, and 16 (35%) in relapse. Nine (20%) patients had MDS with >5% blasts. Treatment with the 131I-BC8 Ab/FLU/TBI regimen produced a remission in all patients, and all had 100% donor CD3+ and CD33+ cell engraftment by day 28 post-transplant. The absolute neutrophil count surpassed 500/uL at a median of 14 (range, 10–19) days, and the self-sustained platelet count surpassed 20,000/uL at a median of 17 days (range, 15–43). Eighteen patients (55%) are surviving disease-free 2 to 16 months (median 9.5 months) post-transplant. In 9 (27%) patients, the disease relapsed 3 to 38 months after HCT. The day-100 non-relapse mortality was 12%. This study demonstrates that at least an average of 27 Gy of targeted radiotherapy can be delivered to bone marrow and an average of 81 Gy to the spleen, in addition to a standard reduced intensity transplant regimen, without a marked increase in day 100 mortality. Whether this approach will reduce post-transplant relapse rates for older patients with high-risk AML/MDS remains to be determined.

We carried out HLA-matched URD peripheral blood stem cell (PBSC) transplant in 24 pts with poor-risk multiple myeloma after nonmyeloablative conditioning with fludarabine (90 mg/m2) and 2 Gy total body irradiation. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. The median age of the 19 men and 5 women was 53 (23 – 66) years. Conventional metaphase cytogenetics obtained in 14 pts showed Δ13 in 6 pts and complex abnormalities in 9 pts. Stage III disease was present in 83% and 17% had stage II disease. The median time from diagnosis to URD HCT was 25 (range, 8–130) months, and 96% were beyond 1st complete remission (CR) or had never achieved CR1, despite multiple lines of chemotherapy (median 4.5, range 2–10). At study entry, 17 pts (71%) had chemotherapy-refractory disease and 14 pts (58%) had failed autologous HCT. Thirteen pts had planned autologous-URD tandem HCT, while 11 proceeded directly to URD HCT. The median follow-up was 2.5 years after allografting. One pt experienced non-fatal graft rejection. The incidences of acute grades II, III and chronic graft-versus-host disease were 54%, 13% and 75%, respectively. Non-relapse mortality was 22% at 2.5 years. CRs were observed in 11 pts (46%) and partial remissions (PR) in 3 (13%). Best disease responses were seen in pts given tandem autologous-URD HCT with CR in 8 pts and PR in 2 pts (77% CR+PR rate). The estimated overall survival (OS) at 2.5 years for all 24 pts was 65% and progression-free survival (PFS) 41%. Pts receiving tandem autologous-URD HCT had superior OS and PFS, 76% and 63% (Fig. A), compared to pts proceeding directly to URD HCT, 52% and 14% (Fig. B), respectively (PFS p-value=.03). Risk factors for worse OS included pts with significant medical comorbidities (p=.03), chemotherapy-refractory disease prior to HCT (p=.03), and pts who had failed autologous HCT (p=.07). Pts who failed autologous HCT had 48% OS and 30% PFS at 2.5 years. For pts with poor-risk, relapsed or refractory multiple myeloma, cytoreductive autologous HCT followed with nonmyeloablative conditioning and URD HCT is very promising treatment with low non-relapse mortality, high complete remission rates and prolonged PFS. The results also suggest that URD HCT may provide improved graft-versus-myeloma effect compared with HLA-matched sibling HCT without an increase in the risk of non-relapse mortality. Figure Figure

Forty-five patients (pts) with relapsed or chemotherapy refractory low-grade lymphomas were treated with HLA-matched related (n=22) and unrelated (n=23) HCT after nonmyeloablative conditioning using 2 Gy total body irradiation with or without fludarabine. Postgrafting immunosuppression consisted of cyclosporine and mycophenolate mofetil. Lymphoma histologies included follicular (n=38), small lymphocytic (n=5), and marginal zone (n=2). Seven pts had prior intermediate-grade lymphoma transformation. The median pt age was 54 (range 34–67) years and median time from diagnosis to allogeneic HCT was 4.3 (0.5–18.5) years. Twelve pts had failed and 3 received cytoreductive autologous HCT before nonmyeloablative HCT. Disease status at time of nonmyeloablative HCT included complete remission (CR, n=16), partial remission (PR, n=12), refractory (n=11) and untested relapse (n=6). Prognostic scoring at the time of HCT using the Follicular Lymphoma International Prognostic Index (FLIPI) identified 25 low-risk and 19 intermediate-risk pts and using the International Prognostic Index (IPI) identified 26 low-risk, 13 low-intermediate risk, and 5 intermediate-high risk pts. There were insufficient data to score 1 pt by the FLIPI or by the IPI. All pts received G-CSF mobilzed peripheral blood mononuclear cells. Six of the 23 unrelated donor graft recipients had human leukocyte antigen (HLA) mismatches: one at a single allele, 4 at a single antigen, and one at an antigen and an allele. The median follow up after nonmyeloblative HCT was 23.8 (range 2– 44.9) months. One pt experienced non-fatal graft rejection of a single antigen mismatched unrelated graft. The cumulative probabilities (CP) of acute grades II-IV, III-IV and chronic GVHD were 60%, 18%, and 51%, respectively. Responses [CR (n=14) and PR (n=6)] were seen in 20 of 28 (71%) pts with measurable disease at HCT while 3 had stable and 3 progressive disease, and 2 were not evaluable due to early nonrelapse death. None of the 20 pts who responded and 3 of the 17 transplanted in CR had disease relapse. At 2 years, the CPs of overall relapse/progression, and non-relapse mortality were 15% and 34%, respectively. The 2-year Kaplan-Meier estimates of overall and progression free survival were 58% and 51%, respectively. Higher IPI and FLIPI scores modeled as continuous variables were independently associated with worse PFS (HR 1.55, p=0.05 and HR 1.35, p=0.10 respectively). Use of a HLA mismatched unrelated donor was associated with a trend for worse OS and PFS (HR 3.0, p=0.08 for both). Allogeneic HCT after nonmyeloablative conditioning is a promising salvage strategy for pts with relapsed and refractory indolent lymphoma. The high response and low relapse rates with this approach suggest that relapsed indolent lymphomas are susceptible to graft-versus-tumor responses.

Background: We previously reported that engraftment across a dog leukocyte antigen (DLA) haplotype-mismatched barrier could be achieved after nonmyeloablative conditioning with 200 cGy total body irradiation (TBI) plus post-grafting mycophenolate mofetil (MMF) /cyclosporine (CSP) when anti-CD44 monoclonal antibody (MAb), S5, is added to the regimen. However, 50% of dogs rejected their grafts after discontinuation of MMF/CSP. Here, we studied the influence of donor lymphocyte infusion (DLI), pentostatin, and graft composition in achievement of sustained full donor chimerism and prevention of rejection. Methods: Twenty-nine dogs were administered MAb S5 (0.2 mg/kg/day) from days -7 to -2, before 200 cGy TBI. Unmodified G-CSF-mobilized peripheral blood stem cells (PBSC) from DLA-haploidentical donors were infused followed by immunosuppression with MMF (5-10 mg/kg BID SQ) and CSP (15 mg/kg BID PO). Dogs in group 1 (n=8) were not given DLI and dogs in group 2 (n=5) were given 6 doses of pentostatin (4 mg/m2/dose) before TBI and no DLI. Dogs in group 3 (n=10) and 4 (n=6) received escalating doses of DLI on days +35, +63, +92. In addition, dogs in group 4 received pentostatin (4 mg/m2) 2 days prior to each infusion of DLI. Results: All dogs achieved initial engraftment between 1 to 2 weeks after transplant and survived 5 weeks or longer with mononuclear cell chimerism ranging from 2% to 98% (median 37%) on day +35. Higher cell subset levels in the PBSC graft were associated with stable donor engraftment: total nucleated cells (p=0.03), CD4+ (p=0.01), CD8+ (p=0.03) and CD14+ (p=0.009) cells. Also, there was a trend in the number of CD34+ (p=0.10) and CD3+(p=0.07) cells. Graft rejection was seen in 7 of 13 dogs without DLI (groups 1 and 2) and in 7 of 16 dogs that received DLI (groups 3 and 4). There was no statistically significant association between DLI and rejection (p=0.44). Six of 16 dogs who received DLI and 1 of 13 dogs with no DLI achieved full donor chimerism (p=0.18), yet there was no statistically significant association between the four groups (p=0.52). There was a trend for higher counts of CD4+ and CD8+ cells (p=0.08) and achievement of full donor chimerism. However, the use of pentostatin before each DLI (group 4) did not impact achievement of full donor chimerism (p>0.95). Duration of mixed chimerism was associated with higher cell subset levels of infused PBSC; CD34+ (p=0.06), CD4+ (p=0.02), CD14+ (p=0.05), CD3+ (p=0.09), CD8+ (p=0.08). Conclusions: The use of DLI with or without prior infusion of pentostatin after initial engraftment of DLA-haploidentical donor graft did not facilitate conversion to full donor chimerism, sustain mixed chimerism, or prevent graft rejection. However, the infusion of haploidentical donor PBSC graft with higher numbers of TNC, CD34+, CD3+, CD4+, CD8+ and CD14+ cells could prolong donor chimerism and prevent graft rejection.

Charlson Comorbidity Index (CCI) is a weighted index that assigns scores to comorbidities and has been applied to predict mortality for patients (pts) with various medical conditions including solid tumors. Recently, CCI was used to predict the risk of non-relapse mortality (NRM) and overall survival (OS) for pts with hematologic malignancies given ablative or nonablative HCT1. The aim of this study is to a) better define previously identified comorbidities, b) investigate additional HCT-related comorbidities, and c) establish comorbidity scores suitable for HCT. We retrospectively reviewed comorbidities and laboratory data of 1058 pts given HCT at our center between 1997–2003 after ablative (n=763) or nonablative (n=295) conditioning (Table 1). The following refinements of the original CCI were made: pulmonary functions tests (PFTs) were used for pulmonary, liver function tests for hepatic, and ejection fraction ≤50% added to cardiac comorbidities. Also, new comorbidities were evaluated including bleeding, recent infections under treatment, depression, and obesity. Pts were randomly divided into a training (n=710) and a testing set (n=349). In the training set, the unadjusted HRs for 2-year NRM were calculated for each comorbidity. These values were then adjusted for other comorbidities, disease risk, conditioning type, and pt age. The adjusted HRs were employed as weights for individual comorbidities (Table 2). The refined pulmonary and hepatic comorbidity definitions were useful in identifying pts with increased risk of NRM. In addition, new comorbidities such as infection, bleeding, depression, and obesity appeared to be predictive. Some comorbidities had higher scores than the original CCI due to higher predictive power in the training set. The modified score was then validated in the testing set. The 2-year rates of NRM for scores of 0, 1–2, and ≥3 were 13%, 24%, and 40%, respectively, and of OS were 71%, 56%, and 37%, respectively. Applying the scores to nonablative and ablative pts, respectively, NRM of 9 vs 12% (p=0.04) were seen for score 0, 17 vs 27% (p=0.002) for scores 1–2, and 39 vs 42% (p=0.18) for scores ≥3. This modified HCT-specific comorbidity index provided a simple, readily applicable and valid method of estimating the risk of NRM and OS among pts given ablative or nonablative HCT. We suggest using this index in assessing risks for NRM and OS before allogeneic HCT. Sorror M et al. Comparing morbidity and mortality of HLA-matched unrelated donor hematopoietic cell transplantation after nonmyeloablative and myeloablative conditioning: influence of pretransplant comorbidities. Blood. Online April 27, 2004; DOI 10.1182/blood-2004-02-0545 Table 1: pts Nonablative(n=295), % Ablative(n=763), % P TBI-total body irradiation, FLU-fludarabine, BU-busulfan, and CY-cyclophosphamide Conditioning TBI 23 0 TBI/FLU 77 0 BU/CY 0 60 CY/TBI 0 40 Age, median (range) years 54 (1–73) 42 (1–66) Table 2: Modified weighted index Comorbidities Assigned weights Hypertension 0 Arrythmia 0 Gastrointestinal 0 Mild PFTs reductions 0 Mild renal 0 Endocrine 0 Cardiac 1 Asthma 1 Mild hepatic 1 Diabetes 1 Cerebrovascular 1 Infection 1 Obesity 1 Bleeding 1 Moderate PFTs reductions 2 Peptic ulcer 2 Depression 2 Valvular 3 Moderate-severe renal 3 Moderate-severe hepatic 3 Prior solid tumor 3 Severe PFTs reductions 4

We have used a nonmyeloablative conditioning regimen consisting of 2 Gy total body irradiation +/− fludarabine, 30 mg/m²/day x 3 days, to condition elderly or ill patients (pts) with hematological malignancies for allogeneic hematopoietic cell transplantation (HCT). This approach relies almost exclusively on graft-versus-tumor (GVT) effects for control of malignancy. Here, we analyzed GVT effects in 322 pts with hematological malignancies given grafts from HLA-matched related (n=192) or unrelated (n=130) donors. Grades I, II, III and IV acute GVHD were seen in 26 (8.1%), 141 (43.8%), 34 (10.6%) and 11 (3.4%) pts, respectively. Extensive chronic GVHD was seen in 181 (56.2%) pts and of these, 64 (19.9%) cases had de novo chronic GVHD. Putative GVT effects were evaluated using time-dependent Cox regression models. Of the 221 pts with measurable disease at HCT, 126 (57%) achieved complete (n=98) or partial (n=28) remissions. Multivariate analysis identified chemosensitivity for B-cell malignancies (p=.02), and tandem autologous/allogeneic HCT (p=.04) as pre-transplant factors associated with higher probabilities of achieving complete remissions (CR) after HCT. After adjusting for these factors, acute GVHD of any grade was not found to be associated with an increased probability of achieving CR. There was a trend for a higher probability of achieving CR in pts with chronic GVHD (p=.07). Progression/relapse was observed in 108 pts. Multivariate analysis identified that lower disease-risk (p=.0004), tandem autologous/allogeneic HCT (p=.02) and adapted Charlson comorbidity index (CCI) score at transplant < 3 (p=.002) resulted in significantly decreased risk of progression/relapse. After correcting for these factors, extensive chronic GVHD was associated with a decreased risk of progression/relapse (p=.006). Pts with grade 1 acute GVHD tended to have less progression/relapse (p=.07). Conversely, grade II–IV acute GVHD did not significantly affect the risk of progression/relapse. Nonrelapse mortality was observed in 70 pts. Multivariate analysis showed that lower disease-risk (p=. 001), tandem autologous/allogeneic HCT (p=.002) and CCI score at transplant < 3 (p

Background: Ph+ is a risk factor for adult ALL and represents an indication for conventional allogeneic HCT. Purpose: To determine whether safety and efficacy of allogeneic HCT can be improved with non-myeloablative conditioning with or without imatinib therapy after HCT for high-risk Ph+ ALL pts ineligible for conventional HCT. Pts and Method: Between 6/2001 to 5/2004, 11 pts [median age of 51 (38–63) years] who had Ph+ ALL received HCT after nonmyeloablative conditioning consisting of fludarabine (30mg/m2/day x 3 days) and 2 Gy TBI followed by mycophenolate mofetil and cyclosporin. Median time from dx to HCT was 13 (range, 6–60) months. PBSC(n=10) or bone marrow (n=1) was infused from 10/10 HLA allele matched (n=9) or mismatched (n=2) unrelated (n=10) or related donors (n=1). Pts were divided into two groups. Group A (n=5): pts did not receive imatinib after HCT. Group B (n=6): pts were entered on a protocol that tested the safety and efficacy of imatinib 600 mg po qd for cytoreduction ( Results: All but one pt, who rejected a marrow graft, had sustained engraftment. Median time of neutrophil recovery (ANC>500) in group A was 18.5 (range, 18–19) days vs 21.6 (range, 20–23) days in group B. Two pts in group B and none in group A required platelet transfusions. Median levels of day 28 donor CD3 and CD33 chimerism were 90% and 90% in group A, respectively vs 81% and 96% in group B. Incidences of grades II-IV GVHD were 40% in group A and 100% in group B while incidences of grade III-IV acute GVHD were 20% and 17%, respectively. One pt (20%) in group A and 3 in group B (50%) developed chronic GVHD. Grade III-IV toxicities in group A pts were 4.0 vs 3.5 events/pt in group B. Three pts in group A (including the pt who rejected the marrow graft) relapsed at days 120, 198 and 365 after HCT, respectively. A fourth group A pt who achieved molecular remission committed suicide at day 90 and the fifth pt is in molecular remission at 6 months after HCT. Of the group B pts, 4 are alive: 2 in molecular remissions at 1 year after HCT, 1 in morphologic and cytogenetic CR but with bcr-abl expression at 1 year; and 1 too early to evaluate. Two group B pts died: one (with pretransplant liver cirrhosis) at day 58 from decompensated liver failure, acute GVHD and disseminated aspergillosis after achieving cytogenetic remission and another from relapse at day 100 after imatinib was discontinued due to presumed skin toxicity. Conclusion: Nonmyeloablative HCT for pts with advanced Ph+ ALL appeared to be feasible and the addition of imatinib after HCT did not appear to increase hematopoietic or other organ toxicity.

Lung function decline is a well-recognized occurrence after myeloablative hematopoietic stem cell transplantation (HCT) that has not been studied after nonmyeloablative conditioning regimens. We examined the lung function of patients before and after receiving nonmyeloablative and myeloablative preparative regimens. Before HCT, nonmyeloablative patients had lower baseline values of percent of predicted FEV1 (pFEV1) and FVC (pFVC), reflecting their greater ages and often, poorer, medical conditions. However, nonmyeloablative patients experienced a slower overall rate of pFEV1 decline after HCT (4% ± 17 versus 12.7% ± 32 per year, P = 0.001), with patients >50 years of age having the lowest risk for rapid pFEV1 decline in a multivariable model. Rapid pFEV1 decline was associated with both total body irradiation (TBI) and non-TBI based myeloablative regimens. These findings were evident even one year or more after HCT. Myeloablative patients had a higher risk for death based upon pretransplant pFEV1 (HR 7.2 versus 3.9), with a 2-year survival rate of 0% among myeloablative patients with a pretransplant pFEV1

Sixty-four patients (pts) with chemotherapy-refractory CLL who were ineligible for ablative allogeneic HCT due to age and/or comorbidities were given nonablative-HCT from related (n=44) or unrelated donors (n=20) between 1997-2003 (Table). Median pt age was 56 (range 44–69) years, interval from diagnosis to HCT was 4.4 (3–25) years, and number of prior regimens was 4 (range 1–12). Sixty-one pts were refractory to at least 1 regimen, 56 to fludarabine (FLU), 19 to alkylating agents, 14 to rituxumab and 4 to CAMPATH, and 2 had failed autologous HCT. Twenty-three pts (36%) had disease responsive to last chemotherapy [28% partial (PR) and 8% complete remission (CR)] while 34 were nonresponsive and 7 had untested relapse. Conditioning for HCT consisted of 2 Gy TBI alone (n=11) or combined with FLU (n=53), 90 mg/m2. Postgrafting immunosuppression consisted of mycophenolate mofetil and cyclosporine. Pts received G-CSF mobilized peripheral blood mononuclear cells. After HCT, pts became neutropenic for a median of 11 days. Forty-four percent of pts had thrombocytopenia ( Table: Results Related (n = 44) Unrelated (n = 20) P Acute GVHD grade II, III, and IV 39%, 11%, and 2% 40%, 20%, and 0% 0.41 2-year chronic extensive GVHD 44% 69% 0.56 Median follow up (range) 31 (3–63) months 12 (3–39) months CR at 2-years 42% 78% 0.005 Relapse/progression at 2 years 34% 5% 0.08 Surviving pts 13 CR, 3 PR, 2 stable, 5 progression, 1 relapse 12 CR, 2 PR, 1 relapse 2-year non-relapse mortality 22% 20% 0.75 2-year disease free survival 44% 75% 0.15 2-year overall survival 56% 74% 0.33

We investigated the feasibility of HLA-matched unrelated donor (URD) HCT in pts with advanced stage, poor-risk multiple myeloma after nonmyeloablative conditioning. Nineteen pts, median age 52 years (range, 28–65), were treated between 5/2000 and 2/2004. Eight pts had known complex cytogenetic abnormalities including Δ13. At study entry, 12 pts had relapsed or refractory disease after a previous autologous HCT, 5 pts had refractory disease following multiple standard chemotherapy regimens, and 2 pts achieved a partial remission (PR) after standard chemotherapy. Before URD HCT, 10 pts underwent a planned high dose autologous HCT (Melphalan 200 mg/m2) to provide cytoreduction a median of 85 days prior to URD HCT, including 4 pts with relapsed/refractory disease after a prior autologous HCT. Three pts were in complete remission (CR) immediately prior to URD HCT. Nonmyeloablative conditioning consisted of fludarabine (30 mg/m2 x 3 days) and 2 Gy total body irradiation followed by PBSC grafts from URDs matched for HLA-A, −B, −C antigens and -DRB1 and -DQB1 alleles. Postgrafting immunosuppression included mycophenolate mofetil and cyclosporine. Durable engraftment was achieved in 18 of 19 pts. One pt had graft rejection at day +56 and received a second successful nonmyeloablative HCT from another URD. Acute GVHD occurred in 13 (68%) pts and was exclusively grades II and III in 11 and 2 pts, respectively. Chronic extensive GVHD occurred in 12/17 (70%) of evaluable pts. After allografting, 9 pts (47%) were in CR and 3 (16%) in PR, for an overall response rate of 63%. Four pts (21%) died of progressive disease and 4 pts (21%) died of non-relapse causes at a median of 5.3 months. The 2-year overall survival, progression-free survival and non-relapse mortality was 62%, 51% and 24%, respectively. The median follow-up was 25 months. Eleven of 19 pts (58%) were alive, 6 (32%) in CR, 1 (5%) in PR, 2 (10%) with stable disease (SD) and 2 (10%) with relapse after initially achieving CR. Of the 10 pts who underwent a planned high dose autologous HCT for cytoreduction followed by nonmyeloablative URD HCT, 8 were alive: 6 CR, 1 SD, 1 relapse. Of the 9 pts who underwent nonmyeloablative URD HCT without planned autologous HCT, 3 were alive: 1 PR, 1 SD and 1 relapse. Of the 12 pts who entered the study with relapsed/refractory disease after a previous autologous HCT, 5 were alive: 2 CR, 1 PR, 1 SD, 1 relapse. In summary, URD HCT after nonmyeloablative conditioning is feasible with relatively low non-relapse mortality and provides a high response rate for pts with relapsed or refractory multiple myeloma, including pts with disease relapse following an autologous HCT. The data suggest that a treatment strategy consisting of two sequential transplants (1) intensive cytoreductive therapy with autologous HCT followed by (2) nonmyeloablative URD HCT, may be highly effective for treating pts with poor risk, chemotherapy-refractory multiple myeloma or after relapse following autologous HCT.

The median age at diagnosis of MDS is 72 years (yrs), and conventional HCT is not an option for many patients (pts). The primary benefit of nonmyeloablative conditioning regimens is a reduction in acute post-HCT morbidity and mortality. However, this benefit may be offset by an increase in post-HCT relapse. To address these issues, we performed a retrospective review of data from 172 pts over age 40 yrs with a diagnosis of MDS or tAML as determined by WHO criteria who underwent HCT between January 1998 and December 2003. Data were analyzed as of July 28, 2004. One hundred thirty two pts were conditioned with a myeloablative regimen of targeted (800–900 ng/ml) busulfan (starting dose 1mg/kg every 6 hours for 16 doses) and cyclophosphamide (120mg/kg) with or without thymoglobulin. Forty pts selected for a nonmyeloablative regimen because of age or comorbid illnesses were conditioned with 2 Gy TBI with or without fludarabine, 30mg/m2/day for three days. The median age was 52 (40–65) yrs for the myeloablative group, and 62 (40–73) yrs for the nonmyeloablative group. The majority of pts in the nonmyeloablative group had progressed to tAML (55%) and had high risk disease by IPSS (55%). The WHO distribution (highest at any time) was as follows: myeloablative/nonmyeloablative- 34%/55% with tAML, 29%/22% with refractory anemia with excess blasts (RAEB-1/2), and 37%/22% with refractory anemia with or without ringed sideroblasts (RA/RARS). The IPSS distribution (highest at any time) was as follows: myeloablative/nonmyeloablative-26%/55% high, 23%/30% int-2, 41%/15% int-1, and 11%/0% low risk. All pts received HCT from HLA-matched related (50% of myeloablative, 65% of nonmyeloablative) or unrelated donors. There were no differences between the two groups with regards to gender distribution, donor CMV status, recipient CMV status, duration of disease prior to HCT, primary or secondary etiology of MDS, or source of stem cells. Overall survival (OS) [46%/31%], relapse free survival (RFS) [40%/28%], and non-relapse mortality [37%/37%] did not differ significantly between myeloablative/nonmyeloablative pts. There was a trend towards improved RFS in pts with RA/RARS (p=0.16) who received myeloablative HCT, and a trend towards improved RFS in pts with tAML who received nonmyeloablative HCT (p=0.14). Among pts with more advanced disease (RAEB-1/2 or tAML) given myeloablative/nonmyeloablative HCT there were 39%/87% who received induction chemotherapy (IC) pre-HCT and 59%/85% given IC achieved a CR. Post-HCT OS and RFS were similar for pts who achieved CR following IC regardless of conditioning regimen used. Thus, while there was a trend towards superior survival with myeloablative HCT in pts with RA/RARS and with nonmyeloablative HCT in pts with tAML, in this retrospective review there were no significant differences between results obtained with myeloablative and nonmyeloablative conditioning regimens. Furthermore, even though most nonmyeloablative pts had high risk disease, there was no significant difference in RFS between the two groups suggesting that a graft vs. tumor effect was more important than conditioning intensity in preventing relapse in pts with high risk MDS or tAML in CR after IC. This raises the question of whether nonmyeloablative HCT should be considered in all pts with high risk MDS or tAML who achieve a CR with IC.

We have shown that graft-versus-host disease (GVHD) after nonmyeloablative hematopoietic cell transplantation (HCT) occurs a median of 2 months later than after myeloablative HCT ( Blood 102:756, 2003). Here, we asked whether there was an association between the time of onset of GVHD and survival after nonablative HCT. We retrospectively analyzed outcomes among 395 patients with hematologic diseases who had nonmyeloablative HCT from HLA-matched related (n=297) or unrelated donors (n=98). The nonablative regimen consisted of 2 Gy total body irradiation with or without fludarabine followed by postgrafting immunosuppression with mycophenolate mofetil and cyclosporine. The cumulative incidences of grades II-IV acute GVHD and extensive chronic GVHD were 45% and 47%, respectively, with grafts from related donors, and 68% and 68%, respectively, with those from unrelated donors. The median time to prednisone initiation, a marker for the onset of both acute and chronic GVHD, was 79 (range, 8–799) days among patients with sibling donors and 28 (range, 5–104) days among patients with unrelated donors. Among patients with GVHD following related grafts (n=187), the cumulative incidence of non-relapse mortality (NRM) at 4 years was 55% among the tertile of patients who initiated prednisone before day 50 (“early initiation”), and 29% when prednisone was initiated on or after day 50 (“late initiation”; p =1) was neither predictive for the time of onset nor the overall incidence of GVHD. Among patients who initiated prednisone for the treatment of GVHD, those with pretransplant comorbidities had a significantly greater hazard of NRM than those without comorbidities (hazard ratio, 2.6; 95% confidence interval, 1.2–5.4; p=0.01). There was no association between time to prednisone initiation and survival after nonmyeloablative HCT from unrelated donors. In conclusion, early-onset GVHD (prednisone initiation before day 50) was associated with increased NRM and poor survival after nonmyeloablative HCT from HLA-identical related donors and identified a subgroup of patients who might benefit from more aggressive primary therapy of GVHD. Hazard of Non-Relapse Mortality According to Time to Prednisone Initiation (HLA-Matched Related Transplants) | Prednisone Initiation for Treatment of GVHD [Day] | Hazard Ratio† | 95% Confidence Interval | P* | P** | |:-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------:| ------------- | ----------------------- | ------ | ----- | | †Cox proportional hazards model treating “early vs. late prednisone initiation” as a time-dependent covariate; *compared to “not initiated”; **comparison of prednisone initiation

We have developed a nonmyeloablative conditioning regimen that combines fludarabine, 3 x 30 mg/m², and 2 Gy total body irradiation to extend unrelated hematopoietic cell transplantation (HCT) to older patients or those with comorbid conditions. Postgrafting immunosuppression consisted of mycophenolate mofetil (MMF) and cyclosporine. After nonmyeloablative conditioning, the cells contained in the graft have been assumed to both create marrow space for donor engraftment and exert graft-versus-tumor effects. In this study, we retrospectively examined whether variations in cellular graft composition correlated with clinical outcomes in 130 consecutive pts given unrelated grafts for treatment of hematological malignancies. Median pt age was 54 (range 5–71) years. Fourteen pts received marrow and 116 G-GSF-mobilized peripheral blood cells (G-PBMC). Graft composition was determined by FACS analyses and expressed as cells/kg of recipient weight. Cell subsets analyzed were total nucleated cells (TNC), monocytes, CD34+, CD3+, CD4+, CD8+, CD3−CD56+, CD3+CD56+ and CD20+ cells. After adjusting for prior chemotherapy treatment, and recent autologous HCT, we found that higher numbers of donor monocytes (p=.003), CD3+ (p=.0007), CD4+ (p=.001), CD8+ (p=.004), CD3−CD56+ (p=.003), and CD34+ (p=.0001) cells were associated with higher levels of day 28 donor T-cell chimerism. When analyses were restricted to G-PBMC recipients, the association remained statistically significant for CD3+ (p=.03), CD4+ (p=.007), CD3−CD56+ (p=.04), and CD34+ (p=.01) cells. After initial engraftment, 6 of 14 marrow recipients and 8 of 116 G-PBMC (p=.001) recipients rejected their grafts. In multivariate analysis, higher numbers of donor CD3+ (p=.02), CD8+ (p=.005) and CD34+ (p=.01) cells were associated with a lower probability of graft rejection. Similar trends were observed in the G-PBMC recipients, although these associations lacked statistical significance, likely as a result of the small number of graft rejection events. Acute graft-versus-host disease (GVHD) of grades II, III and IV occurred in 71 (54.6%), 16 (12.3%) and 2 (1.5%) pts, respectively. Chronic GVHD requiring therapy was seen in 72 (55.4%) pts. After adjusting for pt age, HLA-compatibility, female donor to male recipient, CMV serostatus, malignancy, MMF bid vs tid and Charlson comorbidity scores at transplantation, none of the cell-type variables were significantly associated with acute or chronic extensive GVHD. Fifty-two pts (40%) relapsed/progressed after HCT, and 22 (16.9%) died because of nonrelapse causes. After controlling for autologous/allogeneic HCT, Charlson’s comorbidity index scores at transplantation, and disease risk, none of the cell variables was significantly associated with relapse/progression or nonrelapse mortality, though TNC dose was significantly associated with improved progression-free survival (p=.01); this association was no longer significant (p=.13) when the analysis was restricted to G-PBMC recipients. In conclusion, increasing the CD34+, CD3+ and CD8+ cell doses in the unrelated grafts after nonmyeloablative conditioning improved donor T-cell engraftment without increasing the risk of GVHD.

We have shown safety of unrelated donor hematopoietic cell transplantation (HCT) using nonmyeloablative conditioning with fludarabine (FLU, 90 mg/m2) and 2 Gy total body irradiation (TBI) and post-HCT immunosuppression with MMF (15 mg/kg) and cyclosporine (CSP 5–6.25 mg/kg) both given BID (Maris Blood 2003 Vol 102, No 6). The graft rejection rate in the first 89 pts was 23% and more frequent for marrow (8/18; 44%) than PBSC (13/71; 18%) recipients. Multivariate analysis identified recipients of marrow grafts and those without preceding chemotherapy at highest risk for graft rejection (p=0.006 for each). The t½ of mycophenolic acid, the active metabolite of MMF, was 3 hours, and its binding to IMPDH II rapidly reversible. This led to the hypothesis that exclusive use of PBSC grafts and TID dosing of MMF might result in higher engraftment and lower acute GVHD rates. The current protocol (MMF TID) was identical to the original one (MMF BID) except that all pts received PBSC and were given MMF TID. The protocol’s primary goal was to achieve graft rejection