An oral antiviral against Covid for symptomatic adults who are not hospitalized and who do not risk progression to severe forms of the disease. Pfizer announces the launch of a phase 2-3 clinical trial that will evaluate the safety and efficacy of an investigational antiviral drug (PF-07321332) designed to fight the virus. A therapy that could therefore be administered at the first signs of infection.
The double-blind randomized study will enroll approximately 1,140 participants who will receive either PF-07321332 plus ritonavir or placebo every 12 hours for 5 days. Protease inhibitors such as PF-07321332 – Pfizer recalls – are designed to block the activity of the main enzyme that the coronavirus needs to replicate. The idea is that co-administration with a low dose of ritonavir, another protease inhibitor, will help slow down the metabolism of PF-07321332 allowing it to stay in the body longer at higher concentrations, thus continuing to work to fight Sars-CoV-2.
The first pivotal phase 2-3 study of PF07321332 / ritonavir started in July in non-hospitalized symptomatic adults diagnosed with Covid-19 at increased risk of progressing to severe disease. The new trial aims to test the approach also in symptomatic patients who do not run this risk. If the trial is successful, Pfizer points out, PF-07321332 / ritonavir could respond to “a significant unmet medical need: providing patients with a new oral therapy that could be prescribed at the first sign of infection, without requiring hospitalization. “.