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Hepatitis C virus (HCV) infection is the leading cause of liver disease in hemophilia patients. In those with human immunodeficiency virus (HIV)/HCV coinfection, the rate of liver disease progression is greater than in HCV monoinfected individuals. Despite antiretroviral therapy, which slows HCV liver disease progression, some require transplantation. Whether transplant outcomes are worse in hemophilic (H) rather than nonhemophilic (NH) candidates is unknown. In order to determine rates and predictors of pretransplant and posttransplant survival, we conducted a retrospective observational study using United Network for Organ Sharing national transplant registry data, comparing HCV+ H and NH candidates. We identified 2502 HCV+ liver transplant candidates from 8 US university-based transplant centers, between January 1, 2004 to December 31, 2010, including 144 HIV+ (6%) and 2358 HIV-; 36 H (1%) and 2466 NH; 1213 (48%) transplanted and 1289 not transplanted. Other than male predominance and younger age, each were P < 0.001. Baseline data were comparable between H and NH. In univariate analysis, 90-day pretransplant mortality was associated with higher baseline Model for End-Stage Liver Disease (MELD; hazard ratio [HR] = 1.15; P < 0.001), lower baseline platelet count (HR = 0.9 per 25,000/µL; P = 0.04), and having HIV/HCV+ hemophilia (P = 0.003). In multivariate analysis, pretransplant mortality was associated with higher MELD (P < 0.001) and was significantly greater in HIV+ than HIV- groups (P = 0.001). However, it did not differ between HIV+ H and NH (HR = 1.7; P = 0.36). Among HIV/HCV+, posttransplant mortality was similar between H and NH, despite lower CD4 in H (P = 0.04). In conclusion, this observational study confirms that hemophilia per se does not have a specific influence on transplant outcomes and that HIV infection increases the risk of mortality in both H and NH patients. Liver Transplantation 23 762-768 2017 AASLD., (© 2016 by the American Association for the Study of Liver Diseases.)

A recombinant vaccine containing Aventis Pasteur's canarypox vector (ALVAC)-HIV and gp120 alum decreased the risk of HIV acquisition in the RV144 vaccine trial. The substitution of alum with the more immunogenic MF59 adjuvant is under consideration for the next efficacy human trial. We found here that an ALVAC-simian immunodeficiency virus (SIV) and gp120 alum (ALVAC-SIV + gp120) equivalent vaccine, but not an ALVAC-SIV + gp120 MF59 vaccine, was efficacious in delaying the onset of SIVmac251 in rhesus macaques, despite the higher immunogenicity of the latter adjuvant. Vaccine efficacy was associated with alum-induced, but not with MF59-induced, envelope (Env)-dependent mucosal innate lymphoid cells (ILCs) that produce interleukin (IL)-17, as well as with mucosal IgG to the gp120 variable region 2 (V2) and the expression of 12 genes, ten of which are part of the RAS pathway. The association between RAS activation and vaccine efficacy was also observed in an independent efficacious SIV-vaccine approach. Whether RAS activation, mucosal ILCs and antibodies to V2 are also important hallmarks of HIV-vaccine efficacy in humans will require further studies.

Hepatitis C virus (HCV) is a controversial indication for liver transplantation (LT) in human immunodeficiency virus (HIV)-infected patients because of reportedly poor outcomes. This prospective, multicenter US cohort study compared patient and graft survival for 89 HCV/HIV-coinfected patients and 2 control groups: 235 HCV-monoinfected LT controls and all US transplant recipients who were 65 years old or older. The 3-year patient and graft survival rates were 60% [95% confidence interval (CI) = 47%-71%] and 53% (95% CI = 40%-64%) for the HCV/HIV patients and 79% (95% CI = 72%-84%) and 74% (95% CI = 66%-79%) for the HCV-infected recipients (P < 0.001 for both), and HIV infection was the only factor significantly associated with reduced patient and graft survival. Among the HCV/HIV patients, older donor age [hazard ratio (HR) = 1.3 per decade], combined kidney-liver transplantation (HR = 3.8), an anti-HCV-positive donor (HR = 2.5), and a body mass index < 21 kg/m(2) (HR = 3.2) were independent predictors of graft loss. For the patients without the last 3 factors, the patient and graft survival rates were similar to those for US LT recipients. The 3-year incidence of treated acute rejection was 1.6-fold higher for the HCV/HIV patients versus the HCV patients (39% versus 24%, log rank P = 0.02), but the cumulative rates of severe HCV disease at 3 years were not significantly different (29% versus 23%, P = 0.21). In conclusion, patient and graft survival rates are lower for HCV/HIV-coinfected LT patients versus HCV-monoinfected LT patients. Importantly, the rates of treated acute rejection (but not the rates of HCV disease severity) are significantly higher for HCV/HIV-coinfected recipients versus HCV-infected recipients. Our results indicate that HCV per se is not a contraindication to LT in HIV patients, but recipient and donor selection and the management of acute rejection strongly influence outcomes., (Copyright © 2012 American Association for the Study of Liver Diseases.)

Post-transplant lymphoproliferative disorder (PTLD) has been associated with high mortality, but recent anecdotal survival appeared better. From 1988 to 2010, the NAPRTCS registry had 235 registered PTLD cases. We sent a special 25-point questionnaire study to the NAPRTCS centers with the most recent 150 cases to obtain additional follow-up data not collected in the master registry, our objective being to determine the recent outcomes after PTLD and determine prognostic factors. We received 92 completed responses, in which only 12 (13%) deaths were reported, 2 from nonmedical causes, 10 with a functioning graft. Kaplan-Meier-calculated patient survival was 90.6% at 1 year and 87.4% at 3, 4 and 5 years post-PTLD. Graft survival post-PTLD was 81.8% at 1 year, 68.0% at 3 years and 65.0% at 5 years. Seven patients received a retransplant after PTLD, with no PTLD recurrence reported. Using all 235 PTLD cases, the covariates associated with better patient survival were more recent year of PTLD diagnosis (adjusted hazard ratio AHR 0.86, p < 0.001), and with worse survival were late PTLD (AHR 1.98, p = 0.0176) and patient age above 13 at PTLD (AHR 3.43, p value 0.022). In children with kidney transplants, patient survival has improved with more recent PTLDs., (©2011 The Authors Journal compilation©2011 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Improvements in human immunodeficiency virus (HIV)-associated mortality make it difficult to deny transplantation based upon futility. Outcomes in the current management era are unknown. This is a prospective series of liver or kidney transplant recipients with stable HIV disease. Eleven liver and 18 kidney transplant recipients were followed for a median of 3.4 years (IQR [interquartile range] 2.9-4.9). One- and 3-year liver recipients' survival was 91% and 64%, respectively; kidney recipients' survival was 94%. One- and 3-year liver graft survival was 82% and 64%, respectively; kidney graft survival was 83%. Kidney patient and graft survival were similar to the general transplant population, while liver survival was similar to the older population, based on 1999-2004 transplants in the national database. CD4+ T-cell counts and HIV RNA levels were stable; and there were two opportunistic infections (OI). The 1- and 3-year cumulative incidence (95% confidence intervals [CI]) of rejection episodes for kidney recipients was 52% (28-75%) and 70% (48-92%), respectively. Two-thirds of hepatitis C virus (HCV)-infected patients, but no patient with hepatitis B virus (HBV) infection, recurred. Good transplant and HIV-related outcomes among kidney transplant recipients, and reasonable outcomes among liver recipients suggest that transplantation is an option for selected HIV-infected patients cared for at centers with adequate expertise.

Newer immunosuppressive agents have dramatically reduced the rates of acute graft rejection (AR) over the last decade but may have exacerbated the problem of post-transplant infections (PTI). We analyzed data from the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) to determine the risks of hospitalization from PTI vs. AR in the years 1987-2000. For patients transplanted in 1987, the AR-associated hospitalization rate exceeded the equivalent hospitalization rate for PTI at both early (1-6 months) and later time points (6-24 months). In contrast, for patients transplanted in the year 2000, the PTI-associated hospitalization rate was twice that for AR-associated hospitalization during each time period. During the first two years post-transplant, rates of AR hospitalization trended significantly downwards (p < 0.001) while rates of PTI-associated hospitalization stayed constant. In the 6-24-month time period post-transplant, the risk of bacterial and viral infection-related hospitalization rose significantly from 1987 to 2000 (p < 0.001 for trend by transplant year). We conclude that the causes of hospitalization at all times up to 24 months post-transplant, including the critical early 6 months, have shifted away from AR to PTI.

Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections.

Historically, higher acute rejection rates, earlier first rejection, and an inability to reverse the rejection characterize pediatric renal transplantation. In recent years, short-term (1-year) graft survival of pediatric renal transplants has steadily improved. To test the hypothesis that these improvements were mediated by changes in acute rejection, we considered the rejection profile of patients who received a renal allograft between 1987 and 1989 (cohort A) and compared it with recipients transplanted between 1997 and 1999 (Cohort B). Cohort A comprised 1469 transplants and cohort B comprised 1189 transplants. Restricting the data to the first year of follow-up, rejection ratios were 1.6 and 0.7, respectively (p < 0.001). Sixty per cent of the later cohort (B) were rejection free at 1 year, compared with 29% for the earlier cohort (A) (p < 0.001). Controlling for donor source, the rejection reversal rate for the later cohort was significantly better than that of the early cohort (p < 0.001). Cumulative distribution of times to first rejection was significantly better for cohort B (p < 0.001). One-year graft survival for cohort B at 94% was significantly better than 80% for cohort A (p < 0.001). We conclude that the improved short-term graft survival is mediated by improvements in the rejection profile in more recently transplanted patients and that this may translate into a better half-life for pediatric renal transplant recipients who received an allograft in the years 1997-99.

Background: Because of concerns of increased risk of graft loss with recurrent disease, living donor (LD) transplantation in children with focal segmental glomerulosclerosis (FSGS) has been controversial., Methods: The North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) database from January 1987 to January 2000 was examined to determine differences in demographics, treatment, and outcomes in children with FSGS compared with other renal diseases., Results: Data on 6484 children, 752 (11.6%) with FSGS, demonstrated that FSGS patients were more likely to be older and black, and were less likely to receive either pre-emptive or LD transplant (P < 0.001). No differences existed in human lymphocyte antigen (HLA) matching or immunosuppression regimens. Acute tubular necrosis occurred in more FSGS patients following LD (11.8 vs. 4.6%) or cadaveric (CD; 27.9 vs. 16.3%) transplants (P < 0.001). Graft survival was worse for LD FSGS patients (5 years 69%) compared with no FSGS (82%, P < 0.001) and was not significantly different than CD graft survival in the FSGS (60%) and No FSGS groups (67%). The LD to CD ratios of relative risk of graft failure were higher in FSGS patients (test for interaction, P = 0.01). Recurrence of original disease was the only cause of graft failure that differed between groups (P < 0.001). A greater percentage of LD FSGS graft failures was attributed to recurrence (P = 0.06)., Conclusions: The impact of FSGS on graft survival in children is greatest in LD transplants, resulting in loss of expected LD graft survival advantage. The rationale for LD grafts in children with FSGS should be based on factors other than better outcomes typically associated with LD transplantation.

The purpose of this randomized, double-blind study was to test the safety and immunogenicity of an HIV-1LAI recombinant gp160 (rgp160) vaccine in healthy, uninfected volunteers using accelerated dosing schedules. Thirty volunteers were randomly assigned to receive 50-micrograms doses of rgp160 in one of two immunization schedules. Group 1 received rgp160 at times 0, 1, 2 and 5 months; and group 2 received rgp160 at times 0, 1, 2, 3 and 4 months. The vaccine was safe and stimulated high levels of HIV-1 envelope-specific binding antibody and T cell memory. There was a trend (P < 0.10) suggesting neutralizing antibodies were better induced by the regimen incorporating a rest period before the final immunization in group 1 volunteers. Both accelerated immunization schedules induced immune responses at levels similar to or better than those achieved by four rgp160 vaccine injections given over 12-18 months in other studies.

Objective: To compare the relative safety and efficacy of azathioprine (AZA), methotrexate (MTX), and the combination of both in the treatment of active rheumatoid arthritis (RA)., Methods: Two hundred twelve patients with active RA were entered into a 24-week prospective, controlled, double-blind, multicenter trial and were randomly assigned to 1 of 3 treatment groups., Results: One hundred fifty-eight patients finished 24 weeks of the study. There were no remissions seen but response rates were greater than 30% for all outcome measures. Combination therapy was not statistically superior to MTX therapy alone, but both combination therapy and MTX alone were superior to AZA alone when patients were analyzed by intent-to-treat and with withdrawals treated as therapy failures. If only patients who continued taking the therapy were analyzed, the mean improvement was greater for AZA therapy than for MTX, while the combination remained the most active. Adverse effects on the gastrointestinal tract and elevations of liver enzyme levels were the most frequent causes for discontinuations., Conclusion: Both combination therapy and MTX alone were superior to therapy with AZA alone for active RA but were not statistically different in their effect on outcome assessment.

The precision of the estimated optimum from a response-surface experiment is often indicated via a confidence region about the optimum. Sometimes, because of associated secondary responses, unconstrained optima produce unrealistic operating conditions, even when the true response surface is known. We consider confidence intervals for constrained optima for which the constraint function is known or separately estimated. An example from a cancer combination chemotherapy experiment illustrates the construction of such a region.

Savage score statistics are employed to develop a test for comparing survival distributions with right-hand singly censored data. The procedure is motivated by the interest in developing a powerful method for determining differences when true survival distributions cross. Examination of small-sample characteristics under the null hypothesis indicate that asymptotic critical values yield a slightly conservative test. Power of the test compares favorably with other criteria, including the modified Smirnov procedure, particularly if there is a single crossing of the survival curves.

In work involving modeling of response surfaces to describe the effects of cancer chemotherapy treatments, it is important to define activity and therapeutic synergism in a statistically defensible manner. This requires the construction of confidence intervals around the estimated optimal treatment which has been achieved by use of an indirect method first proposed by Box and Hunter. Activity for a drug or a combination can be claimed at 100(1 - alpha)% level of confidence when the 100(1 - alpha)% confidence interval about the optimal treatment excludes a zero dose. Results of treatment of B16 melanoma and Lewis lung carcinoma with 3,4-dihydroxybenzohydroxamic acid are used to demonstrate this definition. Extensions of this concept lead to a statistically valid definition of therapeutic synergism. If the confidence region about the optimum combination of k drugs does not contact any of the k - 1 dimensional subspaces, then a k drug therapeutic synergism can be claimed. In the event that a k drug therapeutic synergism cannot be claimed, there may be subsets of the drugs which do combine with therapeutic synergy. These concepts are demonstrated by two- and three-drug combination experiments in L1210-bearing C57BL/6 x DBA/2 F1 (B6D2F1) mice. Razoxane and dacarbazine show therapeutic synergism at a 95% confidence level. A three-drug combination of 5-fluorouracil, Teniposide, and mitomycin C is considered. In this case, although the estimated optimum treatment includes 48.1 mg of 5-fluorouracil per kg, 15.9 mg of Teniposide per kg, and 3.9 mg of mitomycin C per kg, the confidence region generated failed to confirm at an 80% level of confidence that 5-fluorouracil was a necessary component of the best treatment.

In this paper, we present a new method for analyzing survival data from combination chemotherapy experiments. The analysis consists of relating survival to the dosage level of each drug in the combination and using response surface techniques to determine the importance of drug interactions and to estimate optimal doses. A combination experiment using cyclophosphamide, mechlorethamine, and mitomycin C in early L1210 leukemia, advanced L1210 leukemia, and advanced P388 leukemia is used to illustrate the analyses. A therapeutic synergism has been shown. As a result of the various drug interactions, the predicted optimal dose of mitomycin C is found to be zero. This result was duplicated in each tumor system studied.

Hazard functions in cancer chemotherapeutic situations may not be proportional, so a nonproportional hazard model has been developed. The dose-response surface is explored by regression analysis of experimental data, and after the estimation of the underlying hazard function the quality of the fit of the model is assessed. Further, treatment levels may be optimized, and estimated survival distributions can be plotted for any treatment combination. In an example of two-drug treatment of murine L1210 leukemia, statistically significant nonproportionality is determined. Analysis permits extraction of potentially important information on drug interrelationships, which has been previously unavailable.