Sarah L. Ondrejka, Paolo Caimi, Ethan Krauspe, Ashley Morrison, Brian T. Hill, Eric D. Hsi, Deepa Jagadeesh, Patrick Collier, Benjamin Tomlinson, Sarah Lehmann, Brad Pohlman, Brenda W. Cooper, Marcos de Lima, Christopher D'Andrea, Alex V. Mejia Garcia, Robert M. Dean, and Allison M. Winter
INTRODUCTION: R-CHOP is effective for diffuse large B-cell Lymphoma (DLBCL), but many patients (Pts) relapse or have refractory disease, likely due to inherent biologic differences in DLBCL subtype. Activated B-Cell (ABC) subtype DLBCL signals through Nuclear Factor-κ-B (NF-κB) and is more likely to display treatment failure than DLBCL arising from the germinal center (GC). Proteasome inhibitors disrupt NF-κB signaling, but randomized trials have failed to demonstrate clinical benefit of adding bortezomib to R-CHOP for the treatment of non-GC DLBCL. Carfilzomib (Car) displays superior clinical activity relative to bortezomib in plasma cell neoplasms and, while occasionally associated with cardiac events, does not have dose-limiting neuropathy. To explore the safety and efficacy of Car in upfront treatment of DLBCL, we initiated a phase I/II clinical trial of Car + R-CHOP and report the phase I results. METHODS: 24 adult (age ≥ 18) Pts with untreated de novo or transformed DLBCL, adequate organ function and performance status were enrolled. During 3 x 3 dose escalation, Car was given at 20 mg/m2 on days 1 and 2, with R-CHOP on day 2 for 6 cycles (n = 6). Due to grade 4 thrombocytopenia, the protocol was amended to administer Car at a dose (in mg/m2) of 20 on days 1 and 2 of cycle 1 with rituximab (R) on day 2 and CHOP on day 3, followed by a Car dose of 20 (n=3), 27 (n=3), 36 (n=3), 45 (n=3) and 54 (n = 6) on days 1 and 2 of cycles 2-6. All Pts received pegfilgrastim the day after CHOP and zoster prophylaxis with acyclovir x 6 months post treatment. Echocardiograms were obtained at baseline and at conclusion of therapy to assess the cardiac safety of combining Car with anthracycline. Interim response assessments with CT +/- PET were performed after cycle 3 and end-of-treatment response assessments were uniformly captured with PET. RESULTS: The median age was 57 (range 24-77) years old. 63% of patients were female. Stage at diagnosis was I-II (58%) or III-IV (32%). The majority of Pts had ECOG performance status of 0-1 (88%). B symptoms were present in 21% of Pts and 54% had an increased LDH at diagnosis. 29% had >1 extranodal site. IPI score was 0-1 (50%), 2 (21%) or 3-4 (39%). For this phase I dose escalation study, eligible Pts included primary mediastinal lymphoma (n = 1) and DLBCL of GC (n = 9), non-GC (n = 13) and unknown (n = 1) Hans algorithm subtypes. Hematologic adverse events (AEs) included 60 grade 1/2, 27 grade 3 and 16 grade 4 AEs. Grade 3/4 hematologic toxicities included neutropenia (n=14), thrombocytopenia (n = 6) anemia (n = 6), with only 4 cases of grade 3 febrile neutropenia. Grade 3/4 non-hematologic AEs were generally consistent with known R-CHOP toxicity were notable for: hypertension (n = 2), decreased ejection fraction (n =2), GI hemorrhage (n = 2) dizziness, headache, and syncope (n = 1 each), thromboembolic event (n=1), hyperglycemia (n=2), increased ALT (n=1) and nausea/vomiting (n=2). Compared to age-matched controls, end-of-treatment echocardiograms of CarR-CHOP treated Pts showed no statistically significant additional effect on ejection fraction (EF) [94.8% vs. 90.0% of pre-treatment value, respectively (P = 0.19)] after 6 cycles of treatment and there was no association of change in EF with Car dose (P = 0.61). There were no dose limiting toxicities. As of June 2018, median follow-up among surviving Pts was 16 months. There were 3 deaths during the study period, 2 from lymphoma and 1 from lung cancer. The overall response rate was 92% [75% complete remission (CR), 17% partial remission]. 18-month Kaplan Meier estimates of PFS and overall survival were 77% and 88%, respectively (Figure). There was no significant difference in CR rates or PFS for patients with GC vs. non-GC subtype (P = 0.65 and 0.61, respectively). CONCLUSION: CarR-CHOP is safe at a recommended phase II dose of 20 mg/m2 on day 1 & 2 for cycle 1 followed by 56 mg/m2 for cycles 2-6, without significant excess cardiac effects. Within the limitations of a prospective phase I clinical trial with potential patient selection bias, preliminary efficacy data suggest a high complete metabolic response rate and equivalent outcomes for patients with GC and non-GC subtype. Phase II accrual is ongoing for non-GC DLBCL only and additional correlative studies of the molecular subtype of DLBCL will be incorporated into future analysis. Disclosures Hill: Amgen: Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Genentech: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Honoraria, Membership on an entity's Board of Directors or advisory committees. Tomlinson:Foundation Medicine: Consultancy. Caimi:Genentech: Membership on an entity's Board of Directors or advisory committees; ADC Therapeutics: Research Funding; Celgene: Speakers Bureau; Kite Pharma: Membership on an entity's Board of Directors or advisory committees.