What happened

Shares of Vir Biotechnology (VIR -5.10%) rose 12% in May, according to data provided by S&P Global Market Intelligence, after the biotech published preclinical data in the journal Nature on S309, a monoclonal antibody that appears to target SARS-CoV-2, the novel coronavirus that causes COVID-19.

So what

The S309 antibody was originally isolated from a patient who recovered from severe acute respiratory syndrome (SARS) in 2003, but it appears that the structure of coronavirus responsible for SARS is close enough to that of the coronavirus that causes COVID-19 that the antibody can bind to both.

Vir is developing two treatments -- VIR-7831 and VIR-7832 -- based on the S309 antibody in collaboration with GlaxoSmithKline (GSK 0.12%). VIR-7831 was engineered to last longer in the body, while VIR-7832 includes that change plus one that may give it the ability to function as a T-cell vaccine.

Patient and doctor behind a caution outbreak alert sign

Image source: Getty Images.

Now what

Vir and GlaxoSmithKline are planning on starting clinical trials for the antibodies this summer. The drugmakers are gearing up to manufacture the commercial supply of the antibodies through a recently announced contract with Biogen.

While the preclinical data looks promising, investors should keep in mind that Vir isn't the only company working on this antibody strategy. Eli Lilly (LLY -1.00%) has already started a clinical trial for its coronavirus-targeting antibody, LY-CoV555. And antibody-powerhouse Regeneron Pharmaceuticals (REGN -1.75%) is also developing a COVID-19 treatment with a cocktail of antibodies.