Wave 3 variants Pfizer has started a Phase 1 trial of a pill that could foil the Covid-19 virus, the company said Tuesday.
The experimental drug inhibits enzymes essential to the replication of the SARS-CoV-2 virus; many successful antiviral drugs against HIV and hepatitis C work the same way.
If clinical trials prove the Pfizer antiviral safe and effective, the pill could be given at the first sign of infection, said the company’s chief scientific officer, Mikael Dolsten, in the announcement.
In morning trading, Pfizer stock (ticker: PFE) was down 1.4%, to $35.50, in a flat stock market.
Pfizer said the drug, dubbed PF-07321332, had shown potent ability to inhibit the SARS-CoV-2 virus and other coronaviruses in laboratory studies. Pfizer is already testing another intravenous antiviral in hospitalized Covid patients.
Merck (MRK) is also testing an antiviral against Covid. Antivirals would be another tool for treating Covid infections, along with the antibody cocktails made by Eli Lilly (LLY) and Regeneron Pharmaceuticals (REGN). Preventing infections, in the first place, is being addressed by vaccines like those from Pfizer and its partner BioNTech (BNTX), Moderna (MRNA) and Johnson & Johnson (JNJ).