Vir Biotechnology Inc. started five years ago with an unconventional plan to tackle infectious diseases, for which pharmaceutical companies had shown little interest in researching new medicines. The emergence of Covid-19 presented the San Francisco-based biotech with an opportunity to make good on its promise. It rapidly designed a monoclonal antibody therapy that worked after other new drugs failed. At one point, Vir’s treatment was the only one of its kind that was effective against the heavily mutated omicron variant, helping fuel the sale of almost 2 million doses of its drug to date.
That success may not last, though. Vir’s own research suggests its Covid drug, sotrovimab, isn’t as potent against the newest mutation of omicron, known as BA.2. The arrival of pills from Pfizer Inc. and Merck & Co. to treat Covid means the medical community may migrate away from antibodies such as Vir’s anyway. Sotrovimab is difficult to administer because it must be given by infusion in a medical center. And cases of Covid are dwindling, cutting into the market for any new antivirals.
