Moderna doses first of 60 participants in COVID-19 booster vaccine study

A study focused on determining whether patients would benefit from a booster for the Moderna, Inc. COVID-19 vaccine has enrolled and dosed its first participants this week.

Moderna’s mRNA COVID-19 vaccine is currently in use across the U.S. and has shown high efficacy against the original strain of the virus. However, with the rise of SARS-CoV-2 variants, such as the deadly and resistant South African strain known as B.1.351, it was determined that boosters might be necessary to guarantee vaccine efficacy.

In previous testing, the Moderna vaccine was shown to still work against B.1.351 but at a sixfold reduction in efficacy. To counter this, it has introduced mRNA-1273.351, a multivalent candidate that takes the authorized vaccine and combines it with the booster into a single vaccine designed to elicit a broad immune response both for new patients and those who have already received the original.

A total of 60 participants will be enrolled in an amended phase two study to determine whether those previously vaccinated will indeed benefit from the booster when pitted against the South Africa-originating strain. The first of these have already been vaccinated. Participants will be divided into three groups: one will get a 20 microgram (µg) dose of a variant-specific booster, another will get a 50 µg dose, and the third will receive a 50 µg dose of a multivalent booster candidate.

The National Institute of Allergy and Infectious Diseases (NIAID) also intends to conduct a phase one clinical trial to determine the monovalent and multivalent modified Moderna vaccines as first use vaccines, as well as booster vaccines for the previously vaccinated. That trial will begin once authorization is granted by the Food and Drug Administration.