Pfizer starts trial of antiviral pill against COVID-19
The mid-to-late-stage study will test Pfizer's novel protease inhibitor, PF-07321332, in up to 2,660 healthy adult participants aged 18 and older who live in the same household as someone with a confirmed symptomatic COVID-19 infection.
The company said the therapy has been specifically designed to be administered orally so that it can potentially be prescribed at the first sign of infection or at first awareness of an exposure, without requiring patients to be hospitalized.
Protease inhibitors, like PF-07321332, are designed to block the activity of the main protease enzyme that the coronavirus needs to replicate, said Pfizer. Co-administration with a low dose of ritonavir is expected to help slow the metabolism, or breakdown, of PF-07321332 in order for it to remain active in the body for longer periods of time at higher concentrations to help combat the virus, according to the developer.
“If successful, we believe this therapy could help stop the virus early – before it has had a chance to replicate extensively – potentially preventing symptomatic disease in those who have been exposed and inhibiting the onset of infection in others,” said Mikael Dolsten, CSO and president, worldwide research, development and medical, Pfizer. “Given the continued emergence and evolution of SARS-CoV-2 variants and their immense impact, we continue to work diligently to develop and study new ways that our investigational oral antiviral candidate could potentially lower the impact of COVID-19, not only on patients’ lives, but also the lives of their families and household members.”
The race is on...
The race has been on to develop an easy-to-administer antiviral pill for COVID-19.
In early September, Merck, known as MSD outside the US and Canada, and its partner, Ridgeback Biotherapeutics, announced the initiation of the Phase 3 MOVe-AHEAD clinical trial to evaluate molnupiravir, an investigational oral antiviral therapeutic for the prevention of COVID-19 infection.
Like the Pfizer trial, this global study is enrolling individuals who are at least 18 years of age and reside in the same household as someone with laboratory-confirmed SARS-CoV-2 infection with symptoms.
In June, Swiss pharma giant, Roche, and partner, Atea Pharmaceuticals, reported early data from a trial of their experimental oral antiviral, AT-527, that indicated it could reduce viral load in hospitalized patients.