An interim review of the data for the Phase 3 trial of the investigational COVID-19 vaccine known as mRNA-1273 suggests that the vaccine is safe and effective at preventing symptomatic COVID-19 in adults, according to press releases.
That was the conclusion of an independent data and safety monitoring board (DSMB) overseeing the Phase 3 trial of the investigational COVID-19 vaccine, which reviewed trial data and shared its interim analysis with the trial oversight group on Nov. 15, 2020.
The mRNA-1273 vaccine candidate was co-developed by the Cambridge, MA-based biotechnology company Moderna, and the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. It combines Moderna's mRNA (messenger RNA) delivery platform with the stabilized SARS-CoV-2 spike immunogen (S-2P) developed by NIAID scientists.
The interim analysis comprised 95 cases of symptomatic COVID-19 among volunteers. The DSMB reported that the candidate was safe and well-tolerated and noted a vaccine efficacy rate of 94.5 percent. The findings are statistically significant, meaning they are likely not due to chance. Ninety of the cases occurred in the placebo group and 5 occurred in the vaccinated group. There were 11 cases of severe COVID-19 out of the 95 total, all of which occurred in the placebo group.
The primary endpoint of the Phase 3 COVE study is based on the analysis of COVID-19 cases confirmed and adjudicated starting two weeks following the second dose of vaccine. This first interim analysis was based on 95 cases, of which 90 cases of COVID-19 were observed in the placebo group versus 5 cases observed in the mRNA-1273 group, resulting in a point estimate of vaccine efficacy of 94.5 percent.
A secondary endpoint analyzed severe cases of COVID-19 and included 11 severe cases (as defined in the study protocol) in this first interim analysis. All 11 cases occurred in the placebo group and none in the mRNA-1273 vaccinated group.
The vaccine candidate transitioned from early development with NIAID to the Biomedical Advanced Research and Development Authority (BARDA), part of the Department of Health and Human Services Office of the Assistant Secretary for Preparedness and Response, for advanced development and manufacturing support.
The Phase 3 vaccine efficacy trial, known as COVE, was begun under OWS, a multi-agency collaboration led by HHS and the Department of Defense that aims to accelerate the development, manufacturing and distribution of medical countermeasures for COVID-19. The Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV) partnership advised on the trial protocol design and endpoints to ensure a harmonized approach across multiple vaccine efficacy trials.
More than 30,000 participants at 100 clinical research sites in the United States are participating in the study, which launched on July 27, 2020, after results from earlier stage clinical testing indicated that the vaccine candidate is well-tolerated and immunogenic. Recognizing the disproportionate impact of the epidemic on underrepresented minority populations, investigators worked with community engagement partners to enroll a diverse pool of participants. 37 percent of trial volunteers are from racial and ethnic minorities.
As part of the arrangement under OWS, representatives from NIAID, BARDA and Moderna are part of the oversight group that receives recommendations from the trial's independent DSMB. The same DSMB also oversees the additional OWS-supported Phase 3 clinical trials evaluating COVID-19 vaccine candidates.
