Johnson & Johnson says its single-dose COVID-19 vaccine is 66% effective
The topline safety and efficacy data are based on 43,783 participants accruing 468 symptomatic cases of COVID-19.
The Phase 3 ENSEMBLE study is designed to evaluate the efficacy and safety of the Janssen COVID-19 vaccine candidate in protecting moderate to severe COVID-19, with co-primary endpoints of 14 days and 28 days following vaccination.
Among all participants from different geographies and including those infected with an emerging viral variant, Janssen’s COVID-19 vaccine candidate was 66% effective overall in preventing moderate to severe COVID-19, 28 days after vaccination.
The onset of protection was observed as early as day 14. The level of protection against moderate to severe COVID-19 infection was 72% in the United States, 66% in Latin America and 57% in South Africa, 28 days post-vaccination.
Prevention of severe disease; protection against COVID-related hospitalization and death The vaccine candidate was 85 percent effective in preventing severe disease across all regions studied 28 days after vaccination in all adults 18 years and older. Efficacy against severe disease increased over time with no cases in vaccinated participants reported after day 49.
The Janssen COVID-19 vaccine candidate demonstrated complete protection against COVID-related hospitalization and death, 28 days post-vaccination. There was a clear effect of the vaccine on COVID-19 cases requiring medical intervention (hospitalization, ICU admission, mechanical ventilation, extracorporeal membrane oxygenation (ECMO), with no reported cases among participants who had received the Janssen COVID-19 vaccine, 28 days post-vaccination.
In the study, the definition of severe COVID-19 disease included laboratory-confirmed SARS-CoV-2 and one or more of the following: signs consistent with severe systemic illness, admission to an intensive care unit, respiratory failure, shock, organ failure or death, among other factors.
Moderate COVID-19 disease was defined as laboratory-confirmed SARS-CoV-2 and one or more of the following: evidence of pneumonia, deep vein thrombosis, shortness of breath or abnormal blood oxygen saturation above 93%, abnormal respiratory rate (≥20); or two or more systemic symptoms suggestive of COVID-19.
Protection was generally consistent across race, age groups, including adults over 60 years of age (N= 13,610), and across all variants and regions studied, including South Africa where nearly all cases of COVID-19 (95%) were due to infection with a SARS-CoV-2 variant from the B.1.351 lineage.
Multi-continent Study Provides Clinical Data on Multiple Emerging Viral Mutations The ENSEMBLE study results include efficacy against newly emerging strains of coronavirus, including some highly infectious variants present in the US, Latin America and South Africa.
The Phase 3 ENSEMBLE trial is being conducted at the height of the COVID-19 pandemic in eight countries and three regions, at a time when disease spread has accelerated throughout the world resulting in people having increased exposure to the virus.
Trial participants of the phase 3 ENSEMBLE study continue to be followed for up to two years for assessments of safety and efficacy. Therefore, these data may be updated based on ongoing analysis. The comprehensive available data set will be submitted to a peer-reviewed journal in the coming weeks.
The analysis included a concurrent review of the available Phase 3 ENSEMBLE study safety data by the Data and Safety Monitoring Board (DSMB), an independent group of experts, that did not report any significant safety concerns relating to the vaccine. A review of adverse events indicated that a single-dose of Janssen’s COVID-19 vaccine candidate was generally well-tolerated.
The safety profile was consistent with other vaccine candidates using Janssen’s AdVac® technology among more than 200,000 people to date. Overall fever rates were 9% and Grade 3 fever 0.2%. Overall serious adverse events (SAEs) reported were higher in participants who received placebo as compared to the active vaccine candidate. No anaphylaxis was observed.
The Company is committed to bringing an affordable COVID-19 vaccine on a not-for-profit basis for emergency pandemic use, pending regulatory authorizations. ■