Drugs, vaccines less effective against new coronavirus variants

Antibody therapies and vaccines for treating or preventing COVID-19 are likely to be less effective against some of the new variants of the coronavirus circulating around the world, a new study suggests.

Of particular concern is the variant identified in South Africa and another one first found in Brazil with similar features. In lab tests, Eli Lilly and Co’s antibody bamlanivimab was inactive against the South Africa strain, according to a report posted on Tuesday on bioRxiv ahead of peer review.

The drug just last week had shown an ability to cut the risk of COVID-19 by 80% for nursing home residents. The activity of one antibody in Regeneron Pharmaceuticals Inc’s dual-antibody therapy was impaired by the South Africa variant, although the cocktail remained potent.

And tests of blood from people who got either of the COVID-19 vaccines from Pfizer Inc or Moderna Inc showed antibodies generated by the shots were less effective against the South Africa variant, although Moderna has said it still believes its vaccine will provide protection.

“Mutationally, this virus is traveling in a direction that could ultimately lead to escape from our current therapeutic and prophylactic interventions,” the researchers said.

“If the rampant spread of the virus continues and more critical mutations accumulate, then we may be condemned to chasing after the evolving SARS-CoV-2 continually, as we have long done for influenza virus.”

Lilly and Regeneron said this week that they are working on new versions of their drugs to address the new variants.