Pfizer launches trial for novel oral COVID-19 therapeutic

An experimental oral antiviral from Pfizer will be the focus of a Phase 1 study involving healthy adults.

Known as PF-07321332, the drug has shown promise during in vitro studies against SARS-CoV-2.

PF-07321332 belongs to a class of drugs known as protease inhibitors, which are commonly used to treat HIV/AIDS and hepatitis C. Protease inhibitors bind to a viral enzyme known as protease to stop viral replication.

Pfizer believes PF-07321332 to be the first orally-administered SARS-CoV-2-specific investigational protease inhibitor to be studied in a clinical trial.

Pfizer is also researching an intravenous protease inhibitor, PF-07304814, for hospitalized COVID-19 patients in a Phase 1b trial.

The most recent trial involving the oral antiviral candidate PF-07321332 will administer multiple ascending doses to evaluate the drug’s safety and tolerability.

Pfizer says the antiviral also has potential in battling other coronaviruses in addition to SARS-CoV-2.

If it ultimately wins regulatory authorization, the drug could be administered quickly at the onset of COVID-19 infection to support the immune system. “We have designed PF-07321332 as a potential oral therapy that could be prescribed at the first sign of infection, without requiring that patients are hospitalized or in critical care,” said Dr. Mikael Dolsten, chief scientific officer and president, worldwide research, development and medical of Pfizer.

The drug could also be administered to hospitalized patients, Dolsten said in a statement.