Phase 2/3 Trial of Molnupiravir for Treatment of Covid-19 in Nonhospitalized Adults.

BACKGROUND: Safe and effective oral treatments are needed to improve clinical outcomes for nonhospitalized patients with Covid-19. Molnupiravir is an orally administered, small-molecule ribonucleoside prodrug shown to inhibit replication of severe acute respiratory syndrome coronavirus 2 in vitro and in animal models. METHODS: MOVe-OUT is an ongoing, phase 2/3, randomized, placebo-controlled, double-blind study evaluating the safety, efficacy, and pharmacokinetics of molnupiravir in nonhospitalized adults. In the phase 2 component, participants had mild or moderate, laboratory-confirmed Covid-19 with sign/symptom onset up to (and including) 7 days before randomization. Participants were randomly assigned 1:1:1:1 to receive 200, 400, or 800 mg of molnupiravir or placebo twice daily for 5 days, stratified by time since sign/symptom onset and by being at increased risk for severe illness from Covid-19. The primary efficacy end point was the proportion of participants who were hospitalized and/or died through day 29. RESULTS: The phase 2 component randomly assigned 302 participants to treatment; baseline characteristics were comparable across treatment groups. Molnupiravir had no apparent dose-related effect on adverse events, and no clinically meaningful abnormalities in laboratory test results were observed in relation to dose or treatment. Eleven participants were hospitalized or died through day 29. Of 225 participants in the combined molnupiravir group, 7 (3.1%) were hospitalized or died, compared with 4 of 74 participants (5.4%) in the placebo group. Subgroup analyses suggested lower incidences of hospitalization and/or death in the molnupiravir versus placebo groups in participants older than 60 years of age, those with increased risk for severe illness, those with symptom onset up to (and including) 5 days before randomization, and those with both symptom onset up to (and including) 5 days before randomization and increased risk for severe illness. CONCLUSIONS: These interim study results support further evaluation of molnupiravir as a potential treatment to reduce hospitalizations and/or death in nonhospitalized patients with Covid-19. (Funded by Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.; ClinicalTrials.gov number, NCT04575597.)

Immunogenicity, safety, and reactogenicity of combined reduced-antigen-content diphtheria-tetanus-acellular pertussis vaccine administered as a booster vaccine dose in healthy Russian participants: a phase III, open-label study.

As vaccine-induced immunity and protection following natural pertussis infection wane over time, adults and adolescents may develop pertussis and become transmitters to unprotected infants. In Russia, diphtheria and tetanus but not pertussis-containing vaccines are registered for older children, adolescents, or adults. The reduced-antigen-content diphtheria toxoid, tetanus toxoid, and acellular pertussis (dTpa) vaccine (Boostrix, GSK) was developed for booster vaccination of children ≥4 years of age, adolescents, and adults. A phase III, open-label, non-randomized study was performed in eight centers in Russia between January and July 2018. The objective of this study was to assess immunogenicity, reactogenicity and safety of a single dose of dTpa vaccine in healthy Russian participants ≥4 years of age (age categories 4-9 years, 10-17 years, 18-64 years, and ≥65 years). At 1 month post-booster vaccination, across all age groups, >99.0% of participants were seroprotected against diphtheria and tetanus and >96.0% of participants were seropositive for anti-pertussis antibodies. For all antibodies across all age groups, antibody GMCs increased from pre- to 1 month post-booster vaccination and booster responses to diphtheria (in 71.5% of participants), tetanus (85.3%), and pertussis antigens (≥85.6%) were observed. One serious adverse event that was not causally related to the study vaccine was reported. No fatal cases were reported throughout the study period. In conclusion, administration of the dTpa vaccine as a booster dose in healthy Russian participants induced a robust immune response to all vaccine antigens and was generally well tolerated across all age groups.

Immunogenicity and safety of a combined DTPa-IPV/Hib vaccine administered as a three-dose primary vaccination course and a booster dose in healthy children in Russia: a phase III, non-randomized, open-label study.

We assessed the immunogenicity and safety of the combined diphtheria-tetanus-acellular pertussis-inactivated poliovirus/Haemophilus influenzae type b vaccine (DTPa-IPV/Hib) in children in Russian Federation aiming to support the registration of the vaccine in Russia. In this phase 3, non-randomized, open-label study (NCT02858440), healthy children received three primary doses at 3, 4.5, and 6 months of age (N = 235) and a booster dose at 18 months of age (N = 225). Seroprotection rates against diphtheria, tetanus, Hib, and poliovirus 1-3, seropositivity rates against pertussis antigens, and antibody geometric mean concentrations/titers for all antigens were evaluated one month post-primary and post-booster vaccinations. Solicited local and general adverse events (AEs) were collected during a 4-day period and unsolicited AEs during a 31-day period post-vaccination. Serious AEs were recorded throughout the study. At post-primary vaccination, all infants were seroprotected against diphtheria, tetanus, and poliovirus 1 and 2, 99.3% against poliovirus 3, and 98.4% against Hib. At least 98.9% of participants were seropositive for the three pertussis antigens. At post-booster vaccination, all toddlers were seroprotected/seropositive against all vaccine components. The most frequent local and general solicited AEs were redness, reported for 52.6% and 44.9% of children, and irritability, reported for 64.7% and 39.1% of children, post-primary and post-booster vaccination, respectively. Unsolicited AEs were reported for 20.4% (post-primary) and 5.8% of children (post-booster vaccination). Most AEs were mild or moderate in intensity. Six serious AEs were reported in three (0.4%) children; none were fatal or assessed as vaccination-related. DTPa-IPV/Hib proved immunogenic and well tolerated in the Russian pediatric population.