Dual-antibody drugs effective against COVID-19 variants in animal study

By Dania Nadeem

June 21 (Reuters) - COVID-19 therapies made from a cocktail
of two types of antibodies were effective against a wide range
of variants of the coronavirus in a mice and hamster study, the
Washington University School of Medicine in St. Louis reported
on Monday.

Antibodies are used to treat cases of COVID-19, often early
in the process. Former U.S. President Donald Trump was treated
by an antibody cocktail by Regeneron Pharmaceuticals in
October after he tested positive for COVID-19.

The latest study included three of the four variants that
have been designated "variants of concern" by the World Health
Organization, including Alpha, first identified in the UK, Beta,
first found in South Africa and Gamma found in Brazil, as well
as an emerging variant from India similar to the Delta variant
of concern.

The U.S. Food and Drug Administration in April revoked the
emergency use authorization of Eli Lilly's single
antibody therapy, bamlanivimab, saying there was increased
circulation of variants resistant to the therapy when used
alone.

Other studies https://www.reuters.com/article/us-health-coronavirus-science-idUSKBN29W2P5
have previously shown that some antibody combination therapies
remained potent against those emerging variants of the
coronavirus that were resistant to single antibody therapies.

The latest study found that combinations of two antibodies
often retained potency against variants even when one of the two
antibodies lost some or all ability to neutralize the variant in
lab studies.

The study, which was conducted in mice and hamsters, tested
all single and combination antibody therapies authorized for
emergency use by the FDA against emerging international and U.S.
variants of the virus.

The researchers evaluated the FDA authorized combination
therapies made by Regeneron, Eli Lilly and a single
antibody therapy, sotrovimab, by Vir Biotechnology Inc
and GlaxoSmithKline Plc.

They also assessed the antibodies currently in clinical
trials by AbbVie Inc, Vir and AstraZeneca.

"Resistance arose with some of the monotherapies, but never
with combination therapy," study co-author Jacco Boon wrote.
(Reporting by Dania Nadeem in Bengaluru; Editing by Lisa
Shumaker)