Johnson & Johnson Announces Successful Phase III Trial of Single-Dose COVID-19 Vaccine with 66% Efficacy Against Moderate to Severe Disease

Johnson & Johnson Announces That Its Investigational Single-Dose COVID-19 Vaccine Candidate (JNJ-78436735) Met All Primary and Key Secondary Endpoints in the Phase 3 ENSEMBLE TrialAnalysis of data from 468 symptomatic COVID-19 cases demonstrated that the vaccine achieved an overall efficacy of 66% in preventing moderate to severe COVID-19 starting 28 days after a single dose. Efficacy varied by region: 72% in the United States, 66% in Latin America, and 57% in South Africa.

Furthermore, the vaccine demonstrated 85% efficacy against severe COVID-19 across all regions. Moreover, its protective effect increased over time; no cases of severe COVID-19 were reported 49 days after vaccination.

Studies have shown that the vaccine can completely prevent COVID-19-related hospitalizations and deaths. In the 28 days following vaccination, no cases of COVID-19 requiring medical intervention (hospitalization, ICU admission, mechanical ventilation, or extracorporeal membrane oxygenation [ECMO]) were reported. The study results demonstrated consistent vaccine efficacy across different ethnicities, age groups (including adults aged 60 years and older), all variants, and study regions—including South Africa, where nearly all COVID-19 cases (95%) were infected with the B.1.351 variant. The ENSEMBLE study results included data on the efficacy against emerging coronavirus strains, including several highly transmissible variants identified in the United States, Latin America, and South Africa.

In terms of safety, a review of adverse events indicated that the vaccine was well tolerated. To date, the safety profile of this vaccine is consistent with that of other vaccines developed using Johnson & Johnson’s AdVac technology. Fever was reported in 9% of participants, with an incidence rate of 0.2% for Grade 3 or higher fever. The overall incidence of serious adverse events (SAEs) was higher in the placebo group than in the vaccine group, and no allergic events were reported. The ENSEMBLE study is a randomized, double-blind, placebo-controlled clinical trial designed to evaluate the safety and efficacy of a single dose of the JNJ-78436735 vaccine versus placebo in preventing moderate to severe COVID-19 infection in adults aged 18 years and older. The study enrolled 43,783 participants across eight countries on three continents (including participants in regions with viral variants), of whom 34% (N=14,672) were aged over 60 years. These participants will continue to be followed for up to two years to assess the safety and efficacy of the vaccine.

In this study, severe COVID-19 was defined as laboratory-confirmed SARS-CoV-2 infection accompanied by one or more of the following: signs consistent with severe systemic illness, admission to the intensive care unit, respiratory failure, shock, organ failure, death, or other factors. Moderate COVID-19 was defined as laboratory-confirmed SARS-CoV-2 infection accompanied by one or more of the following: pneumonia, deep vein thrombosis, shortness of breath or oxygen saturation above 93%, abnormal respiratory rate (≥20 breaths per minute), or two or more systemic symptoms related to COVID-19.

Johnson & Johnson plans to submit in early February toFDASubmit an Emergency Use Authorization (EUA) application, with the expectation of distributing the vaccine immediately upon authorization. This vaccine utilizes the same distribution channels as standard vaccines and can be stored for two years at -20°C (-4°F), or for at least three months at 2-8°C (36-46°F). Johnson & Johnson stated that it will employ the same cold-chain logistics technology currently used to transport other innovative drugs for vaccine delivery.

The Ad26.COV2.S COVID-19 candidate vaccine was developed by Johnson & Johnson using its AdVac vaccine platform, which was also used to develop and produce the Ebola vaccine previously approved by the European Commission. In addition, candidate vaccines for Zika virus, RSV, and HIV were also developed based on this platform.BioValleyBioon.com）