Moderna to begin clinical trial on vaccine booster for South African variant

Feb. 24 (UPI) -- Moderna announced Wednesday it will soon begin testing a version of its COVID-19 vaccine designed to combat a variant of the coronavirus first discovered in South Africa.

The drugmaker issued a statement announcing it had completed manufacturing its first variant-specific vaccine candidate and had shipped doses to the National Institutes of Health for a Phase 1 clinical trial.

Moderna has already begun testing a third dose as a booster shot for those who have received two doses of the vaccine, but in addition to the variant-specific booster it also plans to test a "multivalent booster candidate" combining the already authorized version of the vaccine with a variant-specific version in one dose.

"Moderna is committed to making as many updates to our vaccine as necessary until the pandemic is under control," Moderna CEO Stephane Bancel said in a statement.

South Africa, where the variant known as B.1.351 first emerged, paused its rollout of AstraZeneca's vaccine earlier this month after a study showed it was not as effective against the variant.

To date, there have been 46 reported cases of the B.1.351 variant across 14 states along with 1,881 cases of the British variant B.1.1.7 in 45 states, according to the U.S. Centers for Disease Control and Prevention.

In January, Moderna released data showing that its vaccine produces antibody responses against known variants, including B.1.1.7 and B.1.351.

However, the antibody response was weaker for the South African strain, indicating a "potential risk of earlier waning of immunity."

Pfizer-BioNTech also released a study last month finding that its vaccine will also work to neutralize the variant versions of the coronavirus.