The Ad26.COV2.S vaccine was highly effective against severe-critical coronavirus disease 2019 (Covid-19), hospitalization, and death in the primary phase 3 efficacy analysis.
We conducted the final ...analysis in the double-blind phase of our multinational, randomized, placebo-controlled trial, in which adults were assigned in a 1:1 ratio to receive single-dose Ad26.COV2.S (5×10
viral particles) or placebo. The primary end points were vaccine efficacy against moderate to severe-critical Covid-19 with onset at least 14 days after administration and at least 28 days after administration in the per-protocol population. Safety and key secondary and exploratory end points were also assessed.
Median follow-up in this analysis was 4 months; 8940 participants had at least 6 months of follow-up. In the per-protocol population (39,185 participants), vaccine efficacy against moderate to severe-critical Covid-19 at least 14 days after administration was 56.3% (95% confidence interval CI, 51.3 to 60.8; 484 cases in the vaccine group vs. 1067 in the placebo group); at least 28 days after administration, vaccine efficacy was 52.9% (95% CI, 47.1 to 58.1; 433 cases in the vaccine group vs. 883 in the placebo group). Efficacy in the United States, primarily against the reference strain (B.1.D614G) and the B.1.1.7 (alpha) variant, was 69.7% (95% CI, 60.7 to 76.9); efficacy was reduced elsewhere against the P.1 (gamma), C.37 (lambda), and B.1.621 (mu) variants. Efficacy was 74.6% (95% CI, 64.7 to 82.1) against severe-critical Covid-19 (with only 4 severe-critical cases caused by the B.1.617.2 delta variant), 75.6% (95% CI, 54.3 to 88.0) against Covid-19 leading to medical intervention (including hospitalization), and 82.8% (95% CI, 40.5 to 96.8) against Covid-19-related death, with protection lasting 6 months or longer. Efficacy against any severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was 41.7% (95% CI, 36.3 to 46.7). Ad26.COV2.S was associated with mainly mild-to-moderate adverse events, and no new safety concerns were identified.
A single dose of Ad26.COV2.S provided 52.9% protection against moderate to severe-critical Covid-19. Protection varied according to variant; higher protection was observed against severe Covid-19, medical intervention, and death than against other end points and lasted for 6 months or longer. (Funded by Janssen Research and Development and others; ENSEMBLE ClinicalTrials.gov number, NCT04505722.).
Abstract Purpose Canagliflozin is a sodium-glucose cotransporter 2 inhibitor approved for the treatment of type 2 diabetes mellitus (T2DM). Because T2DM is often associated with renal or hepatic ...impairment, understanding the effects of these comorbid conditions on the pharmacokinetics of canagliflozin, and further assessing its safety, in these special populations is essential. Two open-label studies evaluated the pharmacokinetics, pharmacodynamics (renal study only), and safety of canagliflozin in participants with hepatic or renal impairment. Methods Participants in the hepatic study (8 in each group) were categorized based on their Child-Pugh score (normal hepatic function, mild impairment Child-Pugh score of 5 or 6, and moderate impairment Child-Pugh score of 7–9) and received a single oral dose of canagliflozin 300 mg. Participants in the renal study (8 in each group) were categorized based on their creatinine clearance (CLCR ) (normal renal function CLCR ≥80 mL/min; mild CLCR 50 to <80 mL/min, moderate CLCR 30 to <50 mL/min, or severe CLCR <30 mL/min renal impairment; and end-stage renal disease ESRD) and received a single oral dose of canagliflozin 200 mg; the exception was those with ESRD, who received 1 dose postdialysis and 1 dose predialysis (10 days later). Canagliflozin’s pharmacokinetics and pharmacodynamics (urinary glucose excretion UGE and renal threshold for glucose excretion RTG ) were assessed at predetermined time points. Findings Mean maximum plasma concentration (Cmax ) and area under the plasma concentration-time curve from time zero to infinite (AUC)0–∞ values differed by <11% between the group with normal hepatic function and those with mild and moderate hepatic impairment. In the renal study, the mean Cmax values were 13%, 29%, and 29% higher and the mean AUC0–∞ values were 17%, 63%, and 50% higher in participants with mild, moderate, and severe renal impairment, respectively; values were similar in the ESRD group relative to the group with normal function, however. The amount of UGE declined as renal function decreased, whereas RTG was not suppressed to the same extent in the moderate to severe renal impairment groups (mean RTG , 93–97 mg/dL) compared with the mild impairment and normal function groups (mean RTG , 68–77 mg/dL). Implications Canagliflozin’s pharmacokinetics were not affected by mild or moderate hepatic impairment. Systemic exposure to canagliflozin increased in the renal impairment groups relative to participants with normal renal function. Pharmacodynamic response to canagliflozin, measured by using UGE and RTG , declined with increasing severity of renal impairment. A single oral dose of canagliflozin was well tolerated by participants in both studies. ClinicalTrials.gov identifiers: NCT01186588 and NCT01759576.
In the ENSEMBLE randomized, placebo-controlled phase 3 trial (NCT04505722), estimated single-dose Ad26.COV2.S vaccine efficacy (VE) was 56% against moderate to severe-critical COVID-19. SARS-CoV-2 ...Spike sequences were determined from 484 vaccine and 1,067 placebo recipients who acquired COVID-19. In this set of prespecified analyses, we show that in Latin America, VE was significantly lower against Lambda vs. Reference and against Lambda vs. non-Lambda family-wise error rate (FWER) p < 0.05. VE differed by residue match vs. mismatch to the vaccine-insert at 16 amino acid positions (4 FWER p < 0.05; 12 q-value ≤ 0.20); significantly decreased with physicochemical-weighted Hamming distance to the vaccine-strain sequence for Spike, receptor-binding domain, N-terminal domain, and S1 (FWER p < 0.001); differed (FWER ≤ 0.05) by distance to the vaccine strain measured by 9 antibody-epitope escape scores and 4 NTD neutralization-impacting features; and decreased (p = 0.011) with neutralization resistance level to vaccinee sera. VE against severe-critical COVID-19 was stable across most sequence features but lower against the most distant viruses.
The emergence of multidrug resistant-tuberculosis (MDR-TB), defined as Mycobacterium tuberculosis strains with in vitro resistance to at least isoniazid and rifampicin, has necessitated evaluation ...and validation of appropriate surrogate endpoints for treatment response in drug trials for MDR-TB. The trial that has demonstrated efficacy of bedaquiline, a diarylquinoline that inhibits mycobacterial ATP synthase, possesses the requisite features to conduct this evaluation. Approval of bedaquiline for use in MDR-TB was based primarily on the results of the controlled C208 Stage II study (ClinicalTrials.gov number, NCT00449644) including 160 patients randomized 1:1 to receive bedaquiline or placebo for 24 weeks when added to an 18-24-month preferred five-drug background regimen. Since randomization in C208 Stage II was preserved until study end, the trial results allow for the investigation of the complex relationship between sustained durable outcome with either Week 8 or Week 24 culture conversion as putative surrogate endpoints. The relationship between Week 120 outcome with Week 8 or Week 24 culture conversion was investigated using a descriptive analysis and with a recently developed statistical methodology for surrogate endpoint evaluation using methods of causal inference. The results demonstrate that sputum culture conversion at 24 weeks is more reliable than sputum culture conversion at 8 weeks when assessing the outcome of adding one new drug to a MDR-TB regimen.
In study TMC647055HPC2001, a 3-direct-acting-antiviral (DAA) regimen combining NS3/4A protease inhibitor simeprevir (SMV), non-nucleoside NS5B inhibitor TMC647055/ritonavir (RTV) and NS5A inhibitor ...JNJ-56914845 resulted in high sustained virologic response 12 weeks after actual end of treatment (SVR12) in chronic hepatitis C virus (HCV) genotype 1-infected patients. SVR12 rates were generally lower in the 2-DAA regimen SMV + TMC647055/RTV with or without ribavirin. The objective of this study was to identify and characterise pre-existing and emerging resistance-associated variants (RAVs) in patients enrolled in study TMC647055HPC2001.
HCV population sequencing analyses were performed on baseline isolates from all patients (n = 90) and post-baseline isolates from patients with virologic failure (n = 22). In addition, deep sequencing and phenotypic analyses were performed on selected baseline and post-baseline isolates.
The majority of patients with virologic failure had emerging RAVs to all study drugs at the time of failure: in all 22 patients SMV RAVs emerged at NS3 positions 80, 155, 156 and/or 168, consistent with the known SMV resistance profile. Emerging TMC647055 RAVs at NS5B position 495 were detected in the majority of patients (16/22), and all 5 patients who failed the 3-DAA regimen had emerging JNJ-56914845 RAVs at NS5A positions 30 and/or 31. While at the end of study emerging SMV and TMC647055 RAVs were no longer observed by population sequencing in 40% (8/20) and 62.5% (10/16) of patients with follow-up data available, respectively, emerging JNJ-56914845 RAVs were still detected in all (5/5) patients.
Virologic failure in the 2- and 3-DAA combinations was, in the majority of patients, associated with the emergence of RAVs to all study drugs. While emerging SMV and TMC647055 RAVs became undetectable during follow-up, JNJ-56914845 RAVs in NS5A were still observed at end of study.
NCT01724086 (date of registration: September 26, 2012).
The interpretation of randomized clinical trial results is often complicated by intercurrent events. For instance, rescue medication is sometimes given to patients in response to worsening of their ...disease, either in addition to the randomized treatment or in its place. The use of such medication complicates the interpretation of the intention‐to‐treat analysis. In view of this, we propose a novel estimand defined as the intention‐to‐treat effect that would have been observed, had patients on the active arm been switched to rescue medication if and only if they would have been switched when randomized to control. This enables us to disentangle the treatment effect from the effect of rescue medication on a patient's outcome, while tempering the strong extrapolations that are typically needed when inferring what the intention‐to‐treat effect would have been in the absence of rescue medication. We propose a novel inverse probability weighting method for estimating this effect in settings where the decision to initiate rescue medication is made at one prespecified time point. This estimator relies on specific untestable assumptions, in view of which we propose a sensitivity analysis. We use the method for the analysis of a clinical trial conducted by Janssen Pharmaceuticals, in which patients with type 2 diabetes mellitus can switch to rescue medication for ethical reasons. Monte Carlo simulations confirm that the proposed estimator is unbiased in moderate sample sizes.
The Ad26.COV2.S vaccine is a recombinant, replication-incompetent human adenovirus type 26 vector encoding full-length severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein in a ...prefusion-stabilized conformation.
In an international, randomized, double-blind, placebo-controlled, phase 3 trial, we randomly assigned adult participants in a 1:1 ratio to receive a single dose of Ad26.COV2.S (5×10
viral particles) or placebo. The primary end points were vaccine efficacy against moderate to severe-critical coronavirus disease 2019 (Covid-19) with an onset at least 14 days and at least 28 days after administration among participants in the per-protocol population who had tested negative for SARS-CoV-2. Safety was also assessed.
The per-protocol population included 19,630 SARS-CoV-2-negative participants who received Ad26.COV2.S and 19,691 who received placebo. Ad26.COV2.S protected against moderate to severe-critical Covid-19 with onset at least 14 days after administration (116 cases in the vaccine group vs. 348 in the placebo group; efficacy, 66.9%; adjusted 95% confidence interval CI, 59.0 to 73.4) and at least 28 days after administration (66 vs. 193 cases; efficacy, 66.1%; adjusted 95% CI, 55.0 to 74.8). Vaccine efficacy was higher against severe-critical Covid-19 (76.7% adjusted 95% CI, 54.6 to 89.1 for onset at ≥14 days and 85.4% adjusted 95% CI, 54.2 to 96.9 for onset at ≥28 days). Despite 86 of 91 cases (94.5%) in South Africa with sequenced virus having the 20H/501Y.V2 variant, vaccine efficacy was 52.0% and 64.0% against moderate to severe-critical Covid-19 with onset at least 14 days and at least 28 days after administration, respectively, and efficacy against severe-critical Covid-19 was 73.1% and 81.7%, respectively. Reactogenicity was higher with Ad26.COV2.S than with placebo but was generally mild to moderate and transient. The incidence of serious adverse events was balanced between the two groups. Three deaths occurred in the vaccine group (none were Covid-19-related), and 16 in the placebo group (5 were Covid-19-related).
A single dose of Ad26.COV2.S protected against symptomatic Covid-19 and asymptomatic SARS-CoV-2 infection and was effective against severe-critical disease, including hospitalization and death. Safety appeared to be similar to that in other phase 3 trials of Covid-19 vaccines. (Funded by Janssen Research and Development and others; ENSEMBLE ClinicalTrials.gov number, NCT04505722.).
Summary
Conditional power calculations are frequently used to guide the decision whether or not to stop a trial for futility or to modify planned sample size. These ignore the information in ...short‐term endpoints and baseline covariates, and thereby do not make fully efficient use of the information in the data. We therefore propose an interim decision procedure based on the conditional power approach which exploits the information contained in baseline covariates and short‐term endpoints. We will realize this by considering the estimation of the treatment effect at the interim analysis as a missing data problem. This problem is addressed by employing specific prediction models for the long‐term endpoint which enable the incorporation of baseline covariates and multiple short‐term endpoints. We show that the proposed procedure leads to an efficiency gain and a reduced sample size, without compromising the Type I error rate of the procedure, even when the adopted prediction models are misspecified. In particular, implementing our proposal in the conditional power approach enables earlier decisions relative to standard approaches, whilst controlling the probability of an incorrect decision. This time gain results in a lower expected number of recruited patients in case of stopping for futility, such that fewer patients receive the futile regimen. We explain how these methods can be used in adaptive designs with unblinded sample size re‐assessment based on the inverse normal P‐value combination method to control Type I error. We support the proposal by Monte Carlo simulations based on data from a real clinical trial.
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