Daily Respiratory Research Analysis
Three impactful studies span COVID-19 therapeutics, precision asthma treatment, and neonatal respiratory prevention. A Cochrane review of 11 RCTs finds molnupiravir offers little clinical benefit for outpatients with mild-to-moderate COVID-19 despite faster early viral clearance. The VESTIGE RCT shows dupilumab reduces CT-defined mucus plugs and improves lung function in type 2-high asthma, while a multicenter cohort indicates delayed cord clamping is associated with a markedly lower risk of bro
Summary
Three impactful studies span COVID-19 therapeutics, precision asthma treatment, and neonatal respiratory prevention. A Cochrane review of 11 RCTs finds molnupiravir offers little clinical benefit for outpatients with mild-to-moderate COVID-19 despite faster early viral clearance. The VESTIGE RCT shows dupilumab reduces CT-defined mucus plugs and improves lung function in type 2-high asthma, while a multicenter cohort indicates delayed cord clamping is associated with a markedly lower risk of bronchopulmonary dysplasia in preterm infants <32 weeks.
Research Themes
- Evidence synthesis redefining COVID-19 outpatient antiviral use
- Biologic therapy targeting airway mucus pathology in asthma
- Perinatal practices to prevent neonatal lung morbidity
Selected Articles
1. Molnupiravir for treating COVID-19.
This Cochrane review synthesizing 11 RCTs (31,272 participants) found that in outpatients with mild-to-moderate COVID-19, molnupiravir probably results in little to no reduction in all-cause mortality and may not reduce hospitalization, despite higher early viral clearance. Adverse and serious adverse events were similar to control. Evidence in inpatients remains unclear due to heterogeneity.
Impact: High-quality evidence synthesis directly informs antiviral stewardship and guideline updates for COVID-19. The findings prioritize treatments with proven clinical benefit over virologic endpoints alone.
Clinical Implications: Molnupiravir should be deprioritized for outpatients with mild-to-moderate COVID-19 given minimal effects on mortality and hospitalization; resources should favor agents with demonstrated clinical benefit in current variants. Early viral clearance alone should not guide treatment decisions.
Key Findings
- Across 7 outpatient RCTs (29,238 participants), all-cause mortality at 28–30 days showed little to no difference (RR 0.17, 95% CI 0.04–0.65; absolute reduction ~9 per 10,000).
- Hospitalization may not be reduced (RR 0.70, 95% CI 0.43–1.12); symptom resolution by days 14 or 28 showed little to no difference.
- Viral clearance was higher by day 5 (RR 3.40) but attenuated by day 10 and largely absent by day 14–15; safety profiles were similar with little to no difference in serious adverse events.
Methodological Strengths
- Comprehensive, pre-specified search across multiple registries with inclusion of 11 RCTs and GRADE assessment
- Risk-of-bias assessment and intention-to-treat analyses; outpatient and inpatient populations analyzed
Limitations
- Heterogeneity in vaccination status and circulating variants; inpatient data too heterogeneous for meta-analysis
- Potential publication bias with multiple unpublished trials; clinical relevance of late viral clearance uncertain
Future Directions: Focus on head-to-head comparisons of oral antivirals against current variants, stratified by risk/vaccination; clarify inpatient effectiveness and variant-specific outcomes.
RATIONALE: Five years from the start of the COVID-19 pandemic, morbidity and mortality have subsided. Vaccines have contributed to reducing the risk of infection and severe disease. However, new COVID-19 variants continue to emerge, and the role of oral antivirals such as molnupiravir in preventing progression of disease or hospitalisation must be assessed. OBJECTIVES: To assess the effects of molnupiravir in people with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and mild to moderate symptoms. SEARCH METHODS: We identified all relevant randomised controlled trials (RCTs) by searching the Cochrane COVID-19 Study Register, Science Citation Index Expanded, the World Health Organization (WHO) Global Literature on Coronavirus Disease database, and the COVID Network Meta-Analysis database with no language restrictions up to 26 April 2024. ELIGIBILITY CRITERIA: We considered full-text articles, preprints, abstracts, trial registry records, and reports of ongoing trials. Cluster-RCTs were eligible for inclusion, but cross-over trials were ineligible. Participants had confirmed SARS-CoV-2 infection with or without risk factors for severe disease. The intervention was molnupiravir 800 mg taken orally every 12 hours for five days, and control was no treatment, placebo, or standard of care, as defined by the study authors. We excluded studies comparing molnupiravir with treatment strategies that included molnupiravir.
2. Effect of Dupilumab on Mucus Burden in Patients with Moderate-to-Severe Asthma: The VESTIGE Trial.
In adults with moderate-to-severe, type 2-high asthma, dupilumab reduced CT-quantified mucus plug burden by week 24 and improved lung function among those with high baseline mucus plugs. It also markedly increased the likelihood of achieving FeNO <25 ppb across baseline mucus strata.
Impact: Links a biologic's anti–type 2 effects to structural mucus plug resolution, a key driver of airflow limitation, supporting precision treatment guided by imaging and FeNO.
Clinical Implications: Dupilumab can be prioritized for T2-high asthma with substantial mucus burden to reduce mucus plugs and improve airflow; CT-based mucus plug scoring and FeNO targets may help select and monitor responders.
Key Findings
- High mucus plug score prevalence declined from 67.2% at baseline to 32.8% at week 24 with dupilumab, while placebo remained largely unchanged (73.3%→76.7%).
- Dupilumab increased the odds of achieving FeNO <25 ppb across both high and low baseline mucus plug subgroups (reported OR 6.64).
- Lung function improved in patients with high baseline mucus plug burden receiving dupilumab.
Methodological Strengths
- Randomized, controlled design with objective CT-based mucus plug quantification
- Clinically relevant biomarkers (FeNO) and lung function endpoints
Limitations
- Details on sample size and full statistical outputs are limited in the abstract
- Generalizability may be constrained to T2-high phenotypes and centers with CT scoring expertise
Future Directions: Validate mucus plug reduction as a mediator of exacerbation risk reduction; assess cost-effectiveness of CT-guided biologic selection and FeNO treat-to-target strategies.
RATIONALE: Chronic mucus hypersecretion contributes to airway obstruction in asthma. OBJECTIVES: Assess dupilumab efficacy by baseline mucus plug score. METHODS: In VESTIGE (NCT04400318), adults with moderate-to-severe asthma, baseline blood eosinophils ≥300 cells/μL, and fractional exhaled nitric oxide (FeNO) ≥25 ppb received dupilumab 300 mg ( MEASUREMENTS AND MAIN RESULTS: Fewer dupilumab-receiving patients had high mucus plug score at Week 24 than at baseline (32.8% vs 67.2%); proportions remained similar in placebo-receiving patients (76.7% vs. 73.3%). Dupilumab versus placebo recipients were more likely to achieve FeNO <25 ppb in high-/low-mucus-plug score subgroups (odds ratio: 6.64; CONCLUSIONS: Dupilumab reduced mucus plug scores and improved lung function in patients with moderate-to-severe asthma with high baseline mucus plug score, and increased the likelihood of achieving FeNO <25 ppb regardless of baseline mucus plug score. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/). Clinical trial registration available at www. CLINICALTRIALS: gov, ID: NCT04400318.
3. Effect of delayed cord clamping on the risk of bronchopulmonary dysplasia in preterm infants with respiratory distress.
In a multicenter prospective cohort of 1,283 preterm infants <32 weeks, delayed cord clamping (34.3% uptake) was associated with substantially lower BPD risk versus early clamping (adjusted OR 0.47). No significant difference in BPD severity was observed; benefits were not evident among infants <28 weeks.
Impact: Provides large-scale, contemporary, multicenter evidence linking a low-cost delivery-room practice to reduced neonatal lung morbidity.
Clinical Implications: Delayed cord clamping should be considered standard for preterm infants <32 weeks with respiratory distress to reduce BPD risk, while individualized decisions remain needed for <28 weeks due to uncertain benefit.
Key Findings
- Among 1,283 infants <32 weeks, delayed cord clamping was performed in 34.3% and associated with lower BPD rates (32.5% vs 55.6%; adjusted OR 0.47, 95% CI 0.35–0.62).
- No significant between-group difference in BPD severity distribution (P=0.09).
- In infants <28 weeks (n=227), delayed clamping did not significantly reduce BPD risk after adjustment (OR 0.65, 95% CI 0.30–1.41).
Methodological Strengths
- Prospective multicenter cohort across 26 NICUs with adjustment for confounders
- Large sample enabling subgroup analyses by gestational age
Limitations
- Observational design limits causal inference; potential residual confounding
- Details on standardized respiratory support and criteria for BPD severity not provided in abstract
Future Directions: Randomized or stepped-wedge trials to validate BPD reduction, and mechanistic studies on hemodynamic stabilization and lung injury pathways; clarify applicability in <28 weeks.
PURPOSE: To assess the incidence of bronchopulmonary dysplasia in preterm infants born at < 32 weeks of gestation who received delayed cord clamping rather than early cord clamping. METHODS: During this multicenter, prospective, observational cohort study, data of 1283 infants born at < 32 weeks of gestation who received umbilical cord management between January 1, 2020 and December 31, 2021, were collected from 26 tertiary referral neonatal intensive care units in China. The primary outcome was bronchopulmonary dysplasia. RESULTS: A total of 440 infants (34.3%) received delayed cord clamping. The bronchopulmonary dysplasia rates were 32.5% and 55.6% for infants who received delayed cord clamping and those who received early cord clamping, respectively. After adjusting for potential confounders, the delayed cord clamping group had a lower risk of bronchopulmonary dysplasia (odds ratio [OR], 0.47; 95% confidence interval [CI], 0.35-0.62; P < 0.001). No significant difference in the severity of bronchopulmonary dysplasia was observed between groups (P = 0.09). A subgroup analysis of 227 infants born at < 28 weeks of gestation revealed that 65 (28.6%) received delayed cord clamping, and that 40 (61.5%) of these 65 infants experienced bronchopulmonary dysplasia. After adjusting for potential confounders, the risk of bronchopulmonary dysplasia for the delayed cord clamping group was not decreased (OR, 0.65; 95% CI, 0.30-1.41; P = 0.28). CONCLUSION: Delayed cord clamping independently decreased the risk of bronchopulmonary dysplasia in infants born at < 32 weeks of gestation with moderate-to-severe respiratory distress; however, for those born at < 28 weeks of gestation, this benefit was not observed.