Association Between Lack of Blinding and Mortality Results in Critical Care Randomized Controlled Trials: A Meta-Epidemiological Study

Empirical meropenem versus piperacillin/tazobactam for adult patients with sepsis (EMPRESS) trial: Protocol

BACKGROUND

Piperacillin/tazobactam may be associated with less favourable outcomes than carbapenems in patients with severe bacterial infections, but the certainty of evidence is low.

METHODS

The Empirical Meropenem versus Piperacillin/Tazobactam for Adult Patients with Sepsis (EMPRESS) trial is an investigator-initiated, international, parallel-group, randomised, open-label, adaptive clinical trial with an integrated feasibility phase. We will randomise adult, critically ill patients with sepsis to empirical treatment with meropenem or piperacillin/tazobactam for up to 30 days. The primary outcome is 30-day all-cause mortality. The secondary outcomes are serious adverse reactions within 30 days; isolation precautions due to resistant bacteria within 30 days; days alive without life support and days alive and out of hospital within 30 and 90 days; 90- and 180-day all-cause mortality and 180-day health-related quality of life. EMPRESS will use Bayesian statistical models with weak to somewhat sceptical neutral priors. Adaptive analyses will be conducted after follow-up of the primary outcome for the first 400 participants concludes and after every 300 subsequent participants, with adaptive stopping for superiority/inferiority and practical equivalence (absolute risk difference <2.5%-points) and response-adaptive randomisation. The expected sample sizes in scenarios with no, small or large differences are 5189, 5859 and 2570 participants, with maximum 14,000 participants and ≥99% probability of conclusiveness across all scenarios.

CONCLUSIONS

EMPRESS will compare the effects of empirical meropenem against piperacillin/tazobactam in adult, critically ill patients with sepsis. Due to the pragmatic, adaptive design with high probability of conclusiveness, the trial results are expected to directly inform clinical practice.

Application of the Composite Quality Score (CQS-2B) versus Cochrane's Risk of Bias tool (Version 2) in systematic reviews of clinical trials - an exploratory study

Objectives

To explore whether systematic review conclusions generated from Cochrane's second version of its Risk of Bias tool (RoB 2) for trial appraisal differ when the Composite Quality Score, Version 2.B (CQS-2B) is used instead and to develop a testable hypothesis based on these findings.

Methods

PubMed was searched for one single systematic review. From the review's accepted trials, data concerning effect estimates and overall bias risk according to the RoB 2 tool were extracted. All trial reports were appraised again using the CQS-2B. Datasets were stratified according to overall bias risk (RoB 2) or corroboration (C-) level (CQS-2B). The effect estimates from trials with 'low bias risk' (RoB 2) and with highest C-level (CQS-2B) were pooled separately. These pooled effect estimates were statistically and all clinical conclusions qualitatively compared.

Results

The pooled effect estimates for trials with 'low bias risk' (RoB 2) were -0.07, 95% CI: -0.10 to -0.04 (I2 = 0.0%) and for the highest C-levels (CQS-2B) 0.08, 95% CI: -0.12 to -0.04 (I2 = 57.0%). The difference was statistically not significant (p = 0.70). Contrary to the RoB 2 tool, no clinical conclusions in line with the CQS-2B were made, because the effect estimates were judged to be erroneously overestimated, due to high risk of bias.

Conclusion

A testable hypothesis was generated suggesting that trial appraisal using the CQS-2B may provide more conservative conclusions based on similar data than with the RoB 2 tool.

Corticosteroid in non-COVID-19 induced community-acquired pneumonia, a meta-analysis

BACKGROUND

Corticosteroid treatment in non-COVID-19 induced Community-acquired pneumonia (CAP) remains inconclusive.

OBJECTIVES

We aimed to assess the role of corticosteroid treatment in CAP.

METHODS

We conducted a comprehensive search of online databases, including PubMed, Embase, and Cochrane, to identify articles published from January 1, 2000, to May 5, 2023. Double-blind RCTs were selected. Two authors screened studies and extracted data. The evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach.

RESULTS

We analyzed data from 12 RCTs, involving 2446 patients. Corticosteroids therapy may reduce short-term mortality in patients with severe CAP (sCAP) and shorten the hospital length of stay in patients with CAP. Furthermore, corticosteroids treatment can decrease the risk of requiring mechanical ventilation, developing septic shock and multiple organ dysfunction syndrome (MODS). There were no significant differences between the corticosteroid and control groups concerning gastrointestinal bleeding and nosocomial infection. The use of corticosteroids could increase the risk of hyperglycemia.

CONCLUSION

Corticosteroid treatment for sCAP has the potential to provide benefits in reducing short-term mortality, but this conclusion necessitates more evidence. Besides, we found no evidence that strongly prevents us from using corticosteroids in patients with sCAP or those at risk of progressing to sCAP.

Choosing immunomodulating therapies for the treatment of COVID-19: recommendations based on placebo-controlled trial evidence

BACKGROUND

Immunomodulatory therapy has been extensively studied in randomized clinical trials for the treatment of patients hospitalized for COVID-19 with inconsistent findings. Guideline committees, reviewing the same clinical trial data, have generated different recommendations for immunomodulatory therapy.

OBJECTIVES

We hypothesize that trial design differences, specifically whether the study utilized an open-label or placebo-controlled design, accounted for the inconsistent mortality effects reported in clinical trials of immunomodulator therapies for COVID-19.

SOURCES

We reviewed COVID-19 treatment guidelines (World Health Organization [WHO], Infectious Diseases Society of America [IDSA] and The National Institutes of Health [NIH]) and identified the meta-analyses associated with glucocorticoids, IL-6 inhibitors, JAK kinase inhibitors, and complement C5a inhibitors that were available to the guideline authors at the time recommendations were either made or updated.

CONTENT

We identified a meta-analysis for each of the immunomodulator classes that are included in current COVID-19 treatment guidelines: glucocorticoids [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499-518] (cited 419), IL-6 antagonists [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499-518] (cited 419), JAK inhibitors [Kramer A, Prinz C, Fichtner F, Fischer AL, Thieme V, Grundeis F, et al. Janus kinase inhibitors for the treatment of COVID-19. Cochrane Database Syst Rev. 2022;6:CD015209] (cited 34), and complement C5a inhibitors [Tsai CL, Lai CC, Chen CY, Lee HS. The efficacy and safety of complement C5a inhibitors for patients with severe COVID-19: A systematic review and meta-analysis. Expert Rev Anti Infect Ther. 2023;21:77-86] (cited 1). Using the same randomized clinical trials, we evaluated the four meta-analyses accounting for trial design: placebo-controlled or open-label. Glucocorticoids (Risk Ratio [RR] 0.91 [95% CI, 0.49-1.69]), IL-6 inhibitors sarilumab (RR 1.17 [95% CI, 0.96-01.43]), and tocilizumab (RR 0.95 [95% CI, 0.76-1.19]) did not reduce mortality in placebo-controlled trials, whereas baricitinib did confer a large survival benefit (RR 0.65 [95% CI, 0.52-0.81]). The complement C5a inhibitor, vilobelimab, also reduced mortality in a single placebo-controlled trial (RR 0.76 [95% CI, 0.57-1.0]).

IMPLICATIONS

Placebo-controlled trial evidence indicates that baricitinib should be the first choice immunomodulator for patients hospitalized for COVID-19 who require any form of oxygen support-low- or high-flow oxygen, non-invasive or invasive ventilation. Vilobelimab warrants study in a large placebo-controlled trial. Treatment guidelines for future pandemics should prioritize the results of placebo-controlled trials.

Trial characteristics and treatment effect estimates in randomized controlled trials of Chinese herbal medicine: A meta-epidemiological study

BACKGROUND

Previously published meta-epidemiological studies focused on Western medicine have identified some trial characteristics that impact the treatment effect of randomized controlled trials (RCTs). Nevertheless, it remains unclear if similar associations exist in RCTs on Chinese herbal medicine (CHM). Further, Chinese medicine-related characteristics have not been explored yet.

OBJECTIVE

To investigate trial characteristics related to treatment effect estimates on CHM RCTs.

SEARCH STRATEGY

This meta-epidemiological study searched 5 databases for systematic reviews on CHM treatment published between January 2011 and July 2021.

INCLUSION CRITERIA

An eligible systematic review should only include RCTs of CHM and conduct at least one meta-analysis.

DATA EXTRACTION AND ANALYSIS

Two reviewers independently conducted data extraction on general characteristics of systematic reviews, meta-analyses and included RCTs. They also assessed the risk of bias of RCTs using the Cochrane risk of bias tool. A two-step approach was used for data analyses. The ratio of odds ratios (ROR) and difference in standardized mean differences (dSMD) with 95% confidence interval (CI) were applied to present the difference in effect estimates for binary and continuous outcomes, respectively.

RESULTS

Ninety-one systematic reviews, comprising 1338 RCTs were identified. For binary outcomes, RCTs incorporated with syndrome differentiation (ROR: 1.23; 95 % CI: [1.07, 1.39]), adopting Chinese medicine formula (ROR: 1.19; 95% CI: [1.03, 1.34]), with low risk of bias on incomplete outcome data (ROR: 1.29; 95% CI: [1.06, 1.52]) and selective outcome reporting (ROR: 1.12; 95% CI: [1.01, 1.24]), as well as a trial size ≥ 100 (ROR: 1.23; 95% CI: [1.04, 1.42]) preferred to show larger effect estimates. As for continuous outcomes, RCTs with Chinese medicine diagnostic criteria (dSMD: 0.23; 95% CI: [0.06, 0.41]), judged as high/unclear risk of bias on allocation concealment (dSMD: -0.70; 95% CI: [-0.99, -0.42]), with low risk of bias on incomplete outcome data (dSMD: 0.30; 95% CI: [0.18, 0.43]), conducted at a single center (dSMD: -0.33; 95% CI: [-0.61, -0.05]), not using intention-to-treat analysis (dSMD: -0.75; 95% CI: [-1.43, -0.07]), and without funding support (dSMD: -0.22; 95% CI: [-0.41, -0.02]) tended to show larger effect estimates.

CONCLUSION

This study provides empirical evidence for the development of a specific critical appraisal tool for risk of bias assessments on CHM RCTs. Please cite this article as: Wang BH, Lin YL, Gao YY, Song JL, Qin L, Li LQ, Liu WQ, Zhong CCW, Jiang MY, Mao C, Yang XB, Chung VCH, Wu IXY. Trial characteristics and treatment effect estimates in randomized controlled trials of Chinese herbal medicine: A meta-epidemiological study. J Integr Med. 2024; 22(3): 223-234.

Considerations for open-label randomized clinical trials: Design, conduct, and analysis

Randomization and blinding are regarded as the most important tools to help reduce bias in clinical trial designs. Randomization is used to help guarantee that treatment arms differ systematically only by treatment assignment at baseline, and blinding is used to ensure that differences in endpoint evaluation and clinical decision-making during the trial arise only from the treatment received and not, for example, the expectation or desires of the people involved. However, given that there are times when it is not feasible or ethical to conduct fully blinded trials, we discuss what can be done to improve a trial, including conducting the trial as if it were a fully blinded trial and maintaining confidentiality of ongoing study results. In this article, we review how best to design, conduct, and analyze open-label trials to ensure the highest level of study integrity and the reliability of the study conclusions.

The impact of blinding on estimated treatment effects in randomized clinical trials on acupuncture: A meta-epidemiological study

OBJECTIVE

To evaluate the sole impact of blinding patients and outcome assessors in acupuncture randomized controlled trials (RCTs) on treatment effects while considering the type of outcome measures.

METHODS

We searched databases for the meta-analyses on acupuncture with both blinded and non-blinded RCTs. Mixed-effects meta-regression models estimated the average ratio of odds ratios (ROR) and differences in standardized mean differences (dSMD) for non-blinded RCTs versus blinded mixed-effects meta-regression model.

RESULTS

The study included 96 meta-analyses (1012 trials). The average ROR for lack of patient blinding was 1.08 (95% confidence intervals 0.79-1.49) in 18 meta-analyses with binary patient-reported outcomes. The average ROR for lack of outcome assessor blinding was 0.98 (0.77-1.24) in 43 meta-analyses with binary subjective outcomes. The average dSMD was -0.38 (-0.96 to 0.20) in 10 meta-analyses with continuous patient-reported outcomes. The average dSMD was -0.13 (-0.45 to 0.18) in 25 meta-analyses with continuous subjective outcomes. The results of the subgroup analysis were consistent with the primary analysis findings.

CONCLUSIONS

Blinding of participants and outcome assessors does not significantly influence acupuncture treatment efficacy. It underscores the practical difficulties of blinding in acupuncture RCTs and the necessity to distinguish between trials with and without successful blinding to understand treatment expectations' effects. Enhancing blinding procedures' quality and assessment in future research is crucial for improving RCTs' internal validity and reliability.

Compelling evidence from meta-epidemiological studies demonstrates overestimation of effects in randomized trials that fail to optimize randomization and blind patients and outcome assessors

OBJECTIVES

To investigate the impact of potential risk of bias elements on effect estimates in randomized trials.

STUDY DESIGN AND SETTING

We conducted a systematic survey of meta-epidemiological studies examining the influence of potential risk of bias elements on effect estimates in randomized trials. We included only meta-epidemiological studies that either preserved the clustering of trials within meta-analyses (compared effect estimates between trials with and without the potential risk of bias element within each meta-analysis, then combined across meta-analyses; between-trial comparisons), or preserved the clustering of substudies within trials (compared effect estimates between substudies with and without the element, then combined across trials; within-trial comparisons). Separately for studies based on between- and within-trial comparisons, we extracted ratios of odds ratios (RORs) from each study and combined them using a random-effects model. We made overall inferences and assessed certainty of evidence based on Grading of Recommendations, Assessment, development, and Evaluation and Instrument to assess the Credibility of Effect Modification Analyses.

RESULTS

Forty-one meta-epidemiological studies (34 of between-, 7 of within-trial comparisons) proved eligible. Inadequate random sequence generation (ROR 0.94, 95% confidence interval [CI] 0.90-0.97) and allocation concealment (ROR 0.92, 95% CI 0.88-0.97) probably lead to effect overestimation (moderate certainty). Lack of patients blinding probably overestimates effects for patient-reported outcomes (ROR 0.36, 95% CI 0.28-0.48; moderate certainty). Lack of blinding of outcome assessors results in effect overestimation for subjective outcomes (ROR 0.69, 95% CI 0.51-0.93; high certainty). The impact of patients or outcome assessors blinding on other outcomes, and the impact of blinding of health-care providers, data collectors, or data analysts, remain uncertain. Trials stopped early for benefit probably overestimate effects (moderate certainty). Trials with imbalanced cointerventions may overestimate effects, while trials with missing outcome data may underestimate effects (low certainty). Influence of baseline imbalance, compliance, selective reporting, and intention-to-treat analysis remain uncertain.

CONCLUSION

Failure to ensure random sequence generation or adequate allocation concealment probably results in modest overestimates of effects. Lack of patients blinding probably leads to substantial overestimates of effects for patient-reported outcomes. Lack of blinding of outcome assessors results in substantial effect overestimation for subjective outcomes. For other elements, though evidence for consistent systematic overestimate of effect remains limited, failure to implement these safeguards may still introduce important bias.

Impact of Allocation Concealment and Blinding in Trials Addressing Treatments for COVID-19: A Methods Study

We aimed to assess the impact of allocation concealment and blinding on the results of coronavirus disease 2019 (COVID-19) trials, using the World Health Organization COVID-19 database (to February 2022). We identified 488 randomized trials comparing drug therapeutics with placebo or standard care in patients with COVID-19. We performed random-effects meta-regressions comparing the results of trials with and without allocation concealment and blinding of health-care providers and patients. We found that, compared with trials with allocation concealment, trials without allocation concealment may estimate treatments to be more beneficial for mortality, mechanical ventilation, hospital admission, duration of hospitalization, and duration of mechanical ventilation, but results were imprecise. We did not find compelling evidence that, compared with trials with blinding, trials without blinding produce consistently different results for mortality, mechanical ventilation, and duration of hospitalization. We found that trials without blinding may estimate treatments to be more beneficial for hospitalizations and duration of mechanical ventilation. We did not find compelling evidence that COVID-19 trials in which health-care providers and patients are blinded produce different results from trials without blinding, but trials without allocation concealment estimate treatments to be more beneficial compared with trials with allocation concealment. Our study suggests that lack of blinding may not always bias results but that evidence users should remain skeptical of trials without allocation concealment.

Noninvasive Oxygenation Strategies in Adult Patients With Acute Hypoxemic Respiratory Failure: A Systematic Review and Network Meta-Analysis

BACKGROUND

Several recently published randomized controlled trials have evaluated various noninvasive oxygenation strategies for the treatment of acute hypoxemic respiratory failure.

RESEARCH QUESTION

Which available noninvasive oxygen strategies are effective for acute hypoxic respiratory failure?

STUDY DESIGN AND METHODS

A systematic review of Medline, Embase, Cochrane CENTRAL, CINAHL, Web of Science, MedRxiv, and Research Square was conducted from inception to October 1, 2022. A random effects frequentist network meta-analysis was performed, and the results are presented using absolute risk difference per 1,000 patients. The Grading of Recommendations, Assessment, Development and Evaluation framework was used to rate the certainty of the evidence. Mortality, invasive mechanical ventilation, duration of hospitalization and ICU stay, ventilator-free days, and level of comfort are reported.

RESULTS

Thirty-six trials (7,046 patients) were included. It was found that helmet CPAP probably reduces mortality compared with standard oxygen therapy (SOT) (231 fewer deaths per 1,000; 95% CI, 126-273 fewer) (moderate certainty). A high-flow nasal cannula (HFNC) probably reduces the need for invasive mechanical ventilation (103.5 fewer events per 1,000; 95% CI, 40.5-157.5 fewer) (moderate certainty). All noninvasive oxygenation strategies may reduce the duration of hospitalization as compared with SOT (low certainty). Helmet bilevel ventilation (4.84 days fewer; 95% CI, 2.33-7.36 days fewer) and helmet CPAP (1.74 days fewer; 95% CI, 4.49 fewer-1.01 more) may reduce the duration of ICU stay as compared with SOT (both low certainty). SOT may be more comfortable than face mask noninvasive ventilation and no different in comfort compared with an HFNC (both low certainty).

INTERPRETATION

A helmet interface for noninvasive ventilation probably reduces mortality and the risk of mechanical ventilation, as well as the duration of hospital and ICU stay. An HFNC probably reduces the risk of invasive mechanical ventilation and may be as comfortable as SOT. Further research is necessary to understand the role of these interfaces in acute hypoxemic respiratory failure.

Intravenous vs. intraosseous vascular access during out-of-hospital cardiac arrest - protocol for a randomised clinical trial

Objective

During cardiac arrest, current guidelines recommend attempting intravenous access first and to consider intraosseous access if intravenous access is unsuccessful or impossible. However, these recommendations are only based on very low-certainty evidence. Therefore, the "Intravenous vs Intraosseous Vascular Access During Out-of-Hospital Cardiac Arrest" (IVIO) trial aims to determine whether there is a difference in patient outcomes depending on the type of vascular access attempted during out-of-hospital cardiac arrest. This current article describes the clinical IVIO trial.

Methods

The IVIO trial is an investigator-initiated, randomised trial of intravenous vs. intraosseous vascular access during adult non-traumatic out-of-hospital cardiac arrest in Denmark. The intervention will consist of minimum two attempts (if unsuccessful on the first attempt) to successfully establish intravenous or intraosseous vascular access during cardiac arrest. The intraosseous group will be further randomised to the humeral or tibial site. The primary outcome is sustained return of spontaneous circulation and key secondary outcomes include survival and survival with a favourable neurological outcome at 30 days. A total of 1,470 patients will be included.

Results

The trial started in March 2022 and the last patient is anticipated to be included in the spring of 2024. The primary results will be reported after 90-day follow-up and are anticipated in mid-2024.

Conclusion

The current article describes the design of the Danish IVIO trial. The findings of this trial will help inform future guidelines for selecting the optimal vascular access route during out-of-hospital cardiac arrest.

Heart Rate Characteristics Monitoring for Late-Onset Sepsis in Preterm Infants: A Systematic Review

BACKGROUND

Early diagnosis of late-onset sepsis (LOS) and necrotizing enterocolitis (NEC) by monitoring heart rate characteristics (HRC) of preterm infants might reduce the risk of death and morbidities. We aimed to systematically assess the effects of HRC monitoring on death, LOS, and NEC.

METHODS

A systematic search was performed in MEDLINE, Embase, Cochrane Library, and Web of Science.

RESULTS

Fifteen papers were included in this review. Three of these papers reported results from the only identified randomized controlled trial (RCT). This RCT showed that HRC monitoring resulted in a small but significant reduction in mortality (absolute risk reduction 2.1% [95% confidence interval 0.01-4.14]) without any differences in neurodevelopmental impairment. The risk of bias was rated high due to performance and detection bias and failure to correct for multiple testing. Most diagnostic cohort studies showed high discriminating accuracy in predicting LOS but lacked sufficient quality and generalizability. No studies for the detection of NEC were identified.

CONCLUSION

Supported by multiple observational cohort studies, the RCT identified in this systematic review showed that HRC monitoring as an early warning system for LOS might reduce the risk of death in preterm infants. However, methodological weaknesses and limited generalizability do not justify implementation of HRC in clinical care. A large international RCT is warranted.

Reporting quality of randomized controlled trials evaluating non-vitamin K oral anticoagulants in atrial fibrillation: a systematic review

BACKGROUND

Randomized controlled trials (RCTs) are subject to bias if they lack methodological quality. Furthermore, optimal and transparent reporting of RCT findings aids their critical appraisal and interpretation. This study aimed to comprehensively evaluate the report quality of RCTs of non-vitamin K oral anticoagulants (NOACs) for the treatment of atrial fibrillation (AF) and to analyze the factors influencing the quality.

METHODS

By searching PubMed, Embase, Web of Science, and Cochrane Library databases RCTs published from inception to 2022 evaluating the efficacy of NOACs on AF were collected. By using the 2010 Consolidated Standards for Reporting Tests (CONSORT) statement, the overall quality of each report was assessed.

RESULTS

Sixty-two RCTs were retrieved in this study. The median of overall quality score in 2010 was 14 (range: 8.5-20). The extent of compliance with the Consolidated Standards of Reporting Trials reporting guideline differed substantially across items: 9 items were reported adequately (more than 90%), and 3 were reported adequately in less than 10% of trials. Multivariate linear regression analysis showed that the higher reporting scores were associated with higher journal impact factor (P = 0.01), international collaboration (P < 0.01), and Sources of trial funding (P = 0.02).

CONCLUSIONS

Although a large number of randomized controlled trials of NOACs for the treatment of AF were published after the CONSORT statement in 2010, the overall quality is still not satisfactory, thus weakening their potential utility and may mislead clinical decisions. This survey provides the first hint for researchers conducting trials of NOACs for AF to improve the quality of reports and to actively apply the CONSORT statement.

Extension of the Composite Quality Score (CQS) as an appraisal tool for prospective, controlled clinical therapy trials-A systematic review of meta-epidemiological evidence

AIM

To conduct a survey of current meta-epidemiological studies to identify additional trial design characteristics that may be associated with significant over- or underestimation of the treatment effect and to use such identified characteristics as a basis for the formulation of new CQS appraisal criteria.

MATERIALS AND METHODS

We retrieved eligible studies from two systematic reviews on this topic (latest search May 2015) and searched the databases PubMed and Embase for further studies from June 2015 -March 2022. All data were extracted by one author and verified by another. Sufficiently homogeneous estimates from single studies were pooled using random-effects meta-analysis. Trial design characteristics associated with statistically significant estimates from single datasets (which could not be pooled) and meta-analyses were used as a basis to formulate new or amend existing CQS criteria.

RESULTS

A total of 38 meta-epidemiological studies were identified. From these, seven trial design characteristics associated with statistically significant over- or underestimation of the true therapeutic effect were found.

CONCLUSION

One new criterion concerning double-blinding was added to the CQS, and the original criteria for concealing the random allocation sequence and for minimum sample size were amended.

Remdesivir for the treatment of COVID-19: a systematic review and meta-analysis

BACKGROUND

The benefits of remdesivir in the treatment of hospitalized patients with COVID-19 remain debated with the National Institutes of Health and the World Health Organization providing contradictory recommendations for and against use.

OBJECTIVES

To evaluate the role of remdesivir for hospitalized inpatients as a function of oxygen requirements.

DATA SOURCES

Beginning with our prior systematic review, we searched MEDLINE using PubMed from 15 January 2021 through 5 May 2022.

STUDY ELIGIBILITY CRITERIA

Randomised controlled trials; all languages.

PARTICIPANTS

All hospitalized adults with COVID-19.

INTERVENTIONS

Remdesivir, in comparison to either placebo, or standard of care.

ASSESSMENT OF RISK OF BIAS

We used the ROB-2 criteria.

METHODS OF DATA SYNTHESIS

The primary outcome was mortality, stratified by oxygen use (none, supplemental oxygen without mechanical ventilation, and mechanical ventilation). We conducted a frequentist random effects meta-analysis on the risk ratio scale and, to contextualize the probabilistic benefits, we also performed a Bayesian random effects meta-analysis on the risk difference scale. A ≥1% absolute risk reduction was considered clinically important.

RESULTS

We identified eight randomized trials, totaling 10 751 participants. The risk ratio for mortality comparing remdesivir vs. control was 0.77 (95% CI, 0.5-1.19) in the patients who did not require supplemental oxygen; 0.89 (95% CI, 0.79-0.99) for nonventilated patients requiring oxygen; and 1.08 (95% CI, 0.88-1.31) in the setting of mechanical ventilation. Using neutral priors, the probabilities that remdesivir reduces mortality were 76.8%, 93.8%, and 14.7%, respectively. The probability that remdesivir reduced mortality by ≥ 1% was 77.4% for nonventilated patients requiring oxygen.

CONCLUSIONS

Based on this meta-analysis, there is a high probability that remdesivir reduces mortality for nonventilated patients with COVID-19 requiring supplemental oxygen therapy. Treatment guidelines should be re-evaluated.

Parenteral Vitamin C in Patients with Severe Infection: A Systematic Review

BACKGROUND: Inflammation and oxidative damage caused by severe infections may be attenuated by vitamin C. METHODS: We conducted a systematic review of randomized controlled trials (RCTs) of parenteral vitamin C as combined therapy or monotherapy versus no parenteral vitamin C administered to adults hospitalized with severe infection. The primary outcome was mortality. We performed random-effects meta-analyses and assessed certainty in effect estimates. RESULTS: Of 1547 citations, 41 RCTs (n = 4915 patients) were eligible for inclusion. Low-certainty evidence suggested that vitamin C may reduce in-hospital mortality (21 RCTs, 2762 patients; risk ratio, 0.88 [95% confidence interval (CI), 0.73 to 1.06]), 30-day mortality (24 RCTs, 3436 patients; risk ratio, 0.83 [95% CI, 0.71 to 0.98]), and early mortality (before hospital discharge or 30 days; 34 RCTs, 4366 patients; risk ratio, 0.80 [95% CI, 0.68 to 0.93]). Effects were attenuated in sensitivity analyses limited to published blinded trials at low risk-of-bias (in-hospital mortality: risk ratio, 1.07 [95% CI, 0.92 to 1.24], moderate certainty; 30-day mortality: risk ratio, 0.88 [95% CI, 0.71 to 1.10], low certainty; and early mortality: risk ratio, 0.88 [95% CI, 0.73 to 1.06], low certainty). For 90-day mortality, all trials had low risk-of-bias; moderate-certainty evidence suggested harm (five RCTs, 1722 patients; risk ratio, 1.07 [95% CI, 0.94 to 1.21]). Moderate-certainty evidence suggested an increased risk of hypoglycemia (risk ratio, 1.20 [95% CI, 0.69 to 2.08]). Effects on other secondary outcomes were mixed and informed by low-certainty evidence. No credible subgroup effects were observed for mortality related to cointerventions (monotherapy vs. combined therapy), dose, or type of infection (Covid-19 vs. other). CONCLUSIONS: Overall, evidence from RCTs does not establish a survival benefit for vitamin C in patients with severe infection. (PROSPERO number, CRD42020209187.)