Comparative effectiveness of extended-release naltrexone versus buprenorphine-naloxone for opioid relapse prevention (X:BOT): a multicentre, open-label, randomised controlled trial.

BACKGROUND: Extended-release naltrexone (XR-NTX), an opioid antagonist, and sublingual buprenorphine-naloxone (BUP-NX), a partial opioid agonist, are pharmacologically and conceptually distinct interventions to prevent opioid relapse. We aimed to estimate the difference in opioid relapse-free survival between XR-NTX and BUP-NX. METHODS: We initiated this 24 week, open-label, randomised controlled, comparative effectiveness trial at eight US community-based inpatient services and followed up participants as outpatients. Participants were 18 years or older, had Diagnostic and Statistical Manual of Mental Disorders-5 opioid use disorder, and had used non-prescribed opioids in the past 30 days. We stratified participants by treatment site and opioid use severity and used a web-based permuted block design with random equally weighted block sizes of four and six for randomisation (1:1) to receive XR-NTX or BUP-NX. XR-NTX was monthly intramuscular injections (Vivitrol; Alkermes) and BUP-NX was daily self-administered buprenorphine-naloxone sublingual film (Suboxone; Indivior). The primary outcome was opioid relapse-free survival during 24 weeks of outpatient treatment. Relapse was 4 consecutive weeks of any non-study opioid use by urine toxicology or self-report, or 7 consecutive days of self-reported use. This trial is registered with ClinicalTrials.gov, NCT02032433. FINDINGS: Between Jan 30, 2014, and May 25, 2016, we randomly assigned 570 participants to receive XR-NTX (n=283) or BUP-NX (n=287). The last follow-up visit was Jan 31, 2017. As expected, XR-NTX had a substantial induction hurdle: fewer participants successfully initiated XR-NTX (204 [72%] of 283) than BUP-NX (270 [94%] of 287; p<0·0001). Among all participants who were randomly assigned (intention-to-treat population, n=570) 24 week relapse events were greater for XR-NTX (185 [65%] of 283) than for BUP-NX (163 [57%] of 287; hazard ratio [HR] 1·36, 95% CI 1·10-1·68), most or all of this difference accounted for by early relapse in nearly all (70 [89%] of 79) XR-NTX induction failures. Among participants successfully inducted (per-protocol population, n=474), 24 week relapse events were similar across study groups (p=0·44). Opioid-negative urine samples (p<0·0001) and opioid-abstinent days (p<0·0001) favoured BUP-NX compared with XR-NTX among the intention-to-treat population, but were similar across study groups among the per-protocol population. Self-reported opioid craving was initially less with XR-NTX than with BUP-NX (p=0·0012), then converged by week 24 (p=0·20). With the exception of mild-to-moderate XR-NTX injection site reactions, treatment-emergent adverse events including overdose did not differ between treatment groups. Five fatal overdoses occurred (two in the XR-NTX group and three in the BUP-NX group). INTERPRETATION: In this population it is more difficult to initiate patients to XR-NTX than BUP-NX, and this negatively affected overall relapse. However, once initiated, both medications were equally safe and effective. Future work should focus on facilitating induction to XR-NTX and on improving treatment retention for both medications. FUNDING: NIDA Clinical Trials Network.

NIDA Clinical Trials Network CTN-0051, Extended-Release Naltrexone vs. Buprenorphine for Opioid Treatment (X:BOT): Study design and rationale.

INTRODUCTION: For opioid-dependent patients in the US and elsewhere, detoxification and counseling-only aftercare are treatment mainstays. Long-term abstinence is rarely achieved; many patients relapse and overdose after detoxification. Methadone, buprenorphine-naloxone (BUP-NX) and extended-release naltrexone (XR-NTX) can prevent opioid relapse but are underutilized. This study is intended to develop an evidence-base to help patients and providers make informed choices and to foster wider adoption of relapse-prevention pharmacotherapies. METHODS: The National Institute on Drug Abuse's Clinical Trials Network (CTN) study CTN-0051, X:BOT, is a comparative effectiveness study of treatment for 24weeks with XR-NTX, an opioid antagonist, versus BUP-NX, a high affinity partial opioid agonist, for opioid dependent patients initiating treatment at 8 short-term residential (detoxification) units and continuing care as outpatients. Up to 600 participants are randomized (1:1) to XR-NTX or BUP-NX. RESULTS: The primary outcome is time to opioid relapse (i.e., loss of persistent abstinence) across the 24-week treatment phase. Differences between arms in the distribution of time-to-relapse will be compared (construction of the asymptotic 95% CI for the hazard ratio of the difference between arms). Secondary outcomes include proportions retained in treatment, rates of opioid abstinence, adverse events, cigarette, alcohol, and other drug use, and HIV risk behaviors; opioid cravings, quality of life, cognitive function, genetic moderators, and cost effectiveness. CONCLUSIONS: XR-NTX and BUP-NX differ considerably in their characteristics and clinical management; no studies to date have compared XR-NTX with buprenorphine maintenance. Study design choices and compromises inherent to a comparative effectiveness trial of distinct treatment regimens are reviewed. CLINICAL TRIAL REGISTRATION: NCT02032433.

Cocaine use reduction with buprenorphine (CURB): rationale, design, and methodology.

BACKGROUND: Effective medications to treat cocaine dependence have not been identified. Recent pharmacotherapy trials demonstrate the potential efficacy of buprenorphine (BUP) (alone or with naltrexone) for reducing cocaine use. The National Institute on Drug Abuse Clinical Trials Network (CTN) launched the Cocaine Use Reduction with Buprenorphine (CURB) investigation to examine the safety and efficacy of sublingual BUP (as Suboxone®) in the presence of extended-release injectable naltrexone (XR-NTX, as Vivitrol®) for the treatment of cocaine dependence. This paper describes the design and rationale for this study. METHODS: This multi-site, double-blind, placebo-controlled study will randomize 300 participants across 11 sites. Participants must meet the DSM-IV criteria for cocaine dependence and past or current opioid dependence or abuse. Participants are inducted onto XR-NTX after self-reporting at least 7 days of abstinence from opioids and tolerating a naloxone challenge followed by oral naltrexone and are then randomly assigned to one of three medication conditions (4 mg BUP, 16 mg BUP, or placebo) for 8 weeks. Participants receive a second injection of XR-NTX 4 weeks after the initial injection, and follow-up visits are scheduled at 1 and 3 months post-treatment. Participants receive weekly cognitive behavioral therapy (CBT). Recruitment commenced in September, 2011. Enrollment, active medication, and follow-up phases are ongoing, and recruitment is exceeding targeted enrollment rates. CONCLUSIONS: This research using 2 medications will demonstrate whether BUP, administered in the presence of XR-NTX, reduces cocaine use in adults with cocaine dependence and opioid use disorders and will demonstrate if XR-NTX prevents development of physiologic dependence on BUP.

Risk behaviour and time as covariates for efficacy of the HIV vaccine regimen ALVAC-HIV (vCP1521) and AIDSVAX B/E: a post-hoc analysis of the Thai phase 3 efficacy trial RV 144.

BACKGROUND: The Thai phase 3 HIV vaccine trial RV 144 showed modest efficacy of a vaccine against HIV acquisition. Baseline variables of age, sex, marital status, and risk did not modify vaccine efficacy. We did a post-hoc analysis of the trial's data to investigate behavioural risk and efficacy every 6 months after vaccination. METHODS: RV 144 was a randomised, multicentre, double-blind, placebo-controlled efficacy trial testing the combination of the HIV vaccines ALVAC-HIV (vCP1521) and AIDSVAX B/E to prevent HIV infection or reduce setpoint viral load. Male and female volunteers aged 18-30 years were recruited from the community. In this post-hoc analysis of the modified intention-to-treat population (16,395 participants), HIV risk behaviour was assessed with a self-administered questionnaire at the time of initial vaccination in the trial and every 6 months thereafter for 3 years. We classified participants' behaviour as low, medium, or high risk. Both the acquisition endpoint and the early viral-load endpoint were examined for interactions with risk status over time and temporal effects after vaccination. Multiple proportional hazards regression models with treatment and time-varying risk covariates were analysed. FINDINGS: Risk of acquisition of HIV was low in each risk group, but 9187 (58·2%) participants reported higher-risk behaviour at least once during the study. Participants classified as high or increasing risk at least once during follow-up were compared with those who maintained low-risk or medium-risk behaviour as a time-varying covariate, and the interaction of risk status and acquisition efficacy was significant (p=0·01), with greater benefit in low-risk individuals. Vaccine efficacy seemed to peak early--cumulative vaccine efficacy was estimated to be 60·5% (95% CI 22-80) through the 12 months after initial vaccination--and declined quickly. Vaccination did not seem to affect viral load in either early or late infections. INTERPRETATION: Future HIV vaccine trials should recognise potential interactions between challenge intensity and risk heterogeneity in both population and treatment effects. The regimen tested in the RV 144 phase 3 trial might benefit from extended immunisation schedules. FUNDING: US Army Medical Research and Materiel Command and Division of AIDS, National Institute of Allergy and Infectious Disease, National Institutes of Health.

Wait list status of pediatric dialysis patients in North America.

Kidney transplantation is the treatment of choice for the majority of pediatric patients with end-stage kidney disease. Previous studies demonstrating racial or gender disparities in access to the deceased donor transplant list could not evaluate the impact of medical concerns or patient preference on waitlist status. We undertook a retrospective cohort study using the NAPRTCS registry to begin to determine barriers to wait list registration for kidney transplantation among pediatric dialysis patients. Clinical and demographic factors were compared in listed vs. non-listed patients. Reasons cited for not listing patients were examined by clinical and demographic factors. At dialysis initiation, 88.7% of pediatric dialysis patients were not on the renal transplant wait list. Twelve months after dialysis initiation, 67.1% of pediatric dialysis patients were not on the wait list. The groups least likely to be on the wait list were infants (adjusted OR 0.23, 95% CI 0.16, 0.32) and girls (adjusted OR 0.78, 95% CI 0.67, 0.90) after adjusting for multiple confounders. The reason most often cited for not listing was medical reason for young infants and that the transplant workup was pending for girls. Further study is needed to identify barriers to wait list registration.

Immunization with cocktail of HIV-derived peptides in montanide ISA-51 is immunogenic, but causes sterile abscesses and unacceptable reactogenicity.

BACKGROUND: A peptide vaccine was produced containing B and T cell epitopes from the V3 and C4 Envelope domains of 4 subtype B HIV-1 isolates (MN, RF, CanO, & Ev91). The peptide mixture was formulated as an emulsion in incomplete Freund's adjuvant (IFA). METHODS: Low-risk, healthy adult subjects were enrolled in a randomized, placebo-controlled dose-escalation study, and selected using criteria specifying that 50% in each study group would be HLA-B7+. Immunizations were scheduled at 0, 1, and 6 months using a total peptide dose of 1 or 4 mg. Adaptive immune responses in16 vaccine recipients and two placebo recipients after the 2nd immunization were evaluated using neutralization assays of sera, as well as ELISpot and ICS assays of cryopreserved PBMCs to assess CD4 and CD8 T-cell responses. In addition, (51)Cr release assays were performed on fresh PBMCs following 14-day stimulation with individual vaccine peptide antigens. RESULTS: 24 subjects were enrolled; 18 completed 2 injections. The study was prematurely terminated because 4 vaccinees developed prolonged pain and sterile abscess formation at the injection site-2 after dose 1, and 2 after dose 2. Two other subjects experienced severe systemic reactions consisting of headache, chills, nausea, and myalgia. Both reactions occurred after the second 4 mg dose. The immunogenicity assessments showed that 6/8 vaccinees at each dose level had detectable MN-specific neutralizing (NT) activity, and 2/7 HLA-B7+ vaccinees had classical CD8 CTL activity detected. However, using both ELISpot and ICS, 8/16 vaccinees (5/7 HLA-B7+) and 0/2 controls had detectable vaccine-specific CD8 T-cell responses. Subjects with moderate or severe systemic or local reactions tended to have more frequent T cell responses and higher antibody responses than those with mild or no reactions. CONCLUSIONS: The severity of local responses related to the formulation of these four peptides in IFA is clinically unacceptable for continued development. Both HIV-specific antibody and T cell responses were induced and the magnitude of response correlated with the severity of local and systemic reactions. If potent adjuvants are necessary for subunit vaccines to induce broad and durable immune responses, careful, incremental clinical evaluation is warranted to minimize the risk of adverse events. TRIAL REGISTRATION: ClinicalTrials.gov NCT00000886.

Recurrence of membranoproliferative glomerulonephritis type II in renal allografts: The North American Pediatric Renal Transplant Cooperative Study experience.

Membranoproliferative glomerulonephritis type II (MPGN II) is an uncommon form of complement-dependent acquired renal disease. Although it has been recognized since the 1970s that MPGN II recurs almost universally in renal transplants, data regarding the long-term consequences of disease recurrence are limited. Therefore, a retrospective comparative analysis of 75 patients with MPGN II contained in the North American Pediatric Renal Transplant Cooperative Study transplantation database was performed. Five-year graft survival for patients with MPGN II was significantly worse (50.0 +/- 7.5%) compared with the database as a whole (74.3 +/- 0.6%; P < 0.001). Living related donor organs had a significantly better 5-yr survival (65.9 +/- 10.7%) compared with cadaveric donor organs (34.1 +/- 9.8%; P = 0.004). The primary cause of graft failure in 11 (14.7%) patients was recurrent disease. Supplemental surveys were obtained on 29 (38%) of 75 patients. Analysis of these data indicated that recurrent disease occurred in 12 (67%) of the 18 patients with posttransplantation biopsies. Although there was no correlation between pretransplantation presentation, pre- or posttransplantation C3 levels, and either disease recurrence or graft failure, there was a strong association between heavy proteinuria and disease recurrence. The presence of glomerular crescents in allograft biopsies had a significant negative correlation with graft survival. At last follow-up, patients with recurrent disease had significantly higher serum creatinine and qualitatively more proteinuria than patients without biopsy-proven disease. These data indicate that recurrent MPGN II has a significant negative impact on renal allograft function and survival.

Evaluation of intravenous immunoglobulin as an agent to lower allosensitization and improve transplantation in highly sensitized adult patients with end-stage renal disease: report of the NIH IG02 trial.

Reported are the reduction of anti-HLA antibody levels and improvement of transplant rates by intravenous immunoglobulin (IVIG) in a randomized, double-blind, placebo-controlled clinical trial. Between 1997 and 2000, a total of 101 adult patients with ESRD who were highly sensitized to HLA antigens (panel reactive antibody [PRA] > or =50% monthly for 3 mo) enrolled onto an NIH-sponsored trial (IG02). Patients received IVIG or placebo. Subjects received IVIG 2 g/kg monthly for 4 mo or an equivalent volume of placebo with additional infusions at 12 and 24 mo after entry if not transplanted. If transplanted, additional infusions were given monthly for 4 mo. Baseline PRA levels were similar in both groups. However, IVIG significantly reduced PRA levels in study subjects compared with placebo. Sixteen IVIG patients (35%) and eight placebo patients (17%) were transplanted. Rejection episodes occurred in 9 of 17 IVIG and 1 of 10 placebo subjects. Seven graft failures occurred (four IVIG, three placebo) among adherent patients with similar 2-yr graft survival rates (80% IVIG, 75% placebo). With a median follow-up of 2 yr after transplant, the viable transplants functioned normally with a mean +/- SEM serum creatinine of 1.68 +/- 0.28 for IVIG versus 1.28 +/- 0.13 mg/dl for placebo. Adverse events rates were similar in both groups. We conclude that IVIG is better than placebo in reducing anti-HLA antibody levels and improving transplantation rates in highly sensitized patients with ESRD. Transplant rates for highly sensitized patients with ESRD awaiting kidney transplants are improved with IVIG therapy.

Prospective grading of graft-versus-host disease after unrelated donor marrow transplantation: a grading algorithm versus blinded expert panel review.

In conjunction with a randomized trial of T-cell depletion versus conventional graft-versus-host disease (GVHD) prophylaxis, we assessed GVHD grading by comparing the transplant center 100-day score, a clinically calculated algorithm, and a blinded expert panel review (PR). Weekly skin, gut, and liver clinical staging; clinically verified differential diagnosis; biopsy information; cyclosporine levels; and initiation of treatment were reviewed and graded according to the consensus GVHD grading method modified by a prospectively determined grading algorithm that specified liver and gut downstaging if a differential diagnosis in that organ was identified. Transplant center (TC) determination of maximum grade was compared with the algorithm-calculated grade and the final expert PR. Of 404 patients reviewed, the TC grade concurred with the calculated algorithm grade in 72% (the algorithm upgraded 18% and downgraded 10%), whereas the TC grade agreed with the PR in 77% (the PR upgraded 12% and downgraded 11%). The calculated algorithm grade was nearly fully (92%) concordant with the final PR grade (the PR upgraded 0.7% and downgraded 7%). Blinded, duplicate reviews for quality control (n = 108) agreed with the initial review in 89% of cases. Algorithm and/or PR review reduced the TC-reported incidence of grade II (28% to 23%) and increased grade III (11% to 20%), whereas grade 0 (41% to 42%), grade I (13% to 12%), and grade IV (7% to 6%) were invariant. Recalculation of the algorithm grading without differential diagnosis downstaging reduced agreement with the TC to a small extent. The original algorithm changed 51 (13%) of 404 from grade 0 to II into grade III or IV or vice versa; calculation without the downgrade modified 44 cases (11%). Maximum acute GVHD grade had a major effect on 2-year disease-free survival, but assignment by TC, calculated algorithm, or final PR grade had little effect on survival within grades or grade categories 0 through II versus III or IV. We conclude that detailed and expert PR yields GVHD scoring that is internally consistent and reproducible with 89% concordance. Weekly recording of GVHD stage along with a calculated grading algorithm acknowledging differential diagnoses results in a final and maximum grade nearly fully concordant with the expert blinded PR. Multicenter prospective GVHD scoring using all available weekly staging and differential diagnosis data can be reliably assessed with a clinically relevant algorithm. This approach can thereby reduce investigator bias, facilitate comparison between centers, and perhaps eliminate the need for an expert PR. This technique should be used in future prospective studies of GVHD prophylaxis.

Long-term survival following simultaneous kidney-pancreas transplantation versus kidney transplantation alone in patients with type 1 diabetes mellitus and renal failure.

BACKGROUND: Pancreas transplantation improves quality of life and prevents the progression of secondary complications of diabetes. Whether these benefits translate into a long-term survival advantage is not entirely clear. METHODS: Using the United Network for Organ Sharing database, we analyzed long-term survival in 18,549 patients with type 1 diabetes and renal failure who received a kidney transplant between 1987 and 1996. Patient survival was calculated using the Kaplan-Meier method. Proportional hazards models were used to adjust for effects of differences in recipient and donor variables between simultaneous kidney-pancreas transplants (SKPTs) and kidney-alone transplants. RESULTS: SKPT and living donor kidney recipients had a significant crude survival distribution advantage over cadaver kidney transplant recipients (8-year survival rates: 72% for SKPT recipients, 72% for living donor kidney recipients, and 55% for cadaver kidney recipients). The survival advantage for SKPT recipients over cadaver kidney recipients diminished, but persisted after adjusting for donor and recipient variables and kidney graft function as time-varying covariates. SKPT recipients had a high mortality risk relative to living donor kidney recipients through 18 months posttransplantation (hazards ratio, 2.2; P < 0.001), but had a lower relative risk (hazard ratio, 0.86; P < 0.02) thereafter. In SKPT recipients, maintenance of a functioning pancreas graft was associated with a survival benefit. CONCLUSION: The long-term survival of SKPT recipients is superior to that of cadaver kidney transplant recipients with type 1 diabetes. There is no difference in survival of SKPT recipients and living donor kidney recipients with type 1 diabetes at up to 8 years' follow-up; the former have a greater early mortality risk and the latter have a greater late mortality risk. Results of this study suggest that successful simultaneous kidney-pancreas transplantation is not only life enhancing, but life saving.

Adverse clinical outcomes associated with short stature at dialysis initiation: a report of the North American Pediatric Renal Transplant Cooperative Study.

OBJECTIVE: We examined whether height less than the 1% for age (z score <-2.5) at dialysis initiation predicts adverse clinical outcomes for children with kidney failure. DESIGN: National cohort study of children initiating dialysis, followed for a minimum of 1 month to a maximum of 8 years. SETTING: Voluntary consortium of pediatric nephrology centers across the United States and Canada in the North American Pediatric Renal Transplant Cooperative Study. PATIENTS: Two thousand three hundred six patients