COVID-19 Vaccines: Pfizer-BioNTech Efficacy at 6 Months / Moderna Variant Trial / J&J Delay

By Amy Orciari Herman

Edited by André Sofair, MD, MPH

Here's some of the latest news on the COVID-19 vaccines:

Pfizer-BioNTech efficacy at 6 months: The Pfizer-BioNTech COVID-19 vaccine has 91.3% efficacy against symptomatic illness diagnosed from 1 week to 6 months after the second dose of vaccine, the companies reported on Thursday. In particular, there were 850 confirmed COVID-19 cases in the placebo group versus 77 in the vaccine group out of some 46,000 trial participants. The vaccine also showed 100% efficacy against CDC-defined severe disease (32 cases with placebo, none with the vaccine). Data from 12,000 vaccine recipients revealed no serious safety concerns. In South Africa in particular, where 800 participants were enrolled and the more transmissible B.1.351 variant is prevalent, the vaccine was 100% efficacious against symptomatic illness: Of the nine cases in the placebo group, six were found to be caused by the B.1.351 variant, suggesting that the vaccine is efficacious against this lineage.

Moderna variant trial: A version of Moderna's vaccine designed to protect against the B.1.351 variant has begun testing in a phase 1 trial sponsored by the National Institute of Allergy and Infectious Diseases. The trial will enroll 210 volunteers, some of whom have previously received the original Moderna vaccine, and will test the candidate vaccine (known as mRNA-1273.351) alone or in various combinations with the original vaccine (see details of the regimens in the news release linked below). The trial's aim is to assess the candidate vaccine's safety, reactogenicity, and ability to induce an immune response.

J&J delay: A mix-up at a large manufacturing plant in Baltimore resulted in contamination of 15 million doses of Johnson & Johnson's single-dose COVID-19 vaccine, the New York Times reports. Future shipments of the vaccine will be delayed while the FDA investigates, calling into question the fate of 24 million doses expected to be shipped over the next month. The mistake does not affect shipments going out to states next week, as those doses were manufactured in the Netherlands.