Objective: a drug to prevent Covid-19 in families where there is a person infected with the virus. Protecting adults exposed to infection with oral antiviral therapy. It is with this objective that Pfizer announces that it has launched a phase 2/3 study (baptized Epic-Pep) on an oral antiviral candidate to be used in ‘post-exposure prophylaxis’ mode in the over 18. It is, explains the company, the third study launched in this global clinical research program.
Under the researchers’ lens a protease inhibitor – PF-07321332, co-administered with a low dose of ritonavir (protease inhibitor already widely used for HIV) – which will be evaluated precisely within families where there is is a Covid patient. PF-07321332 has been specifically designed to be administered orally, so that it can potentially be given – explains Pfizer – at the first sign of infection or exposure to Sars-CoV-2, without requiring hospitalization of patients.
The study is enrolling people aged 18 and over living with patients who have a symptomatic confirmed SARS-CoV-2 infection. “We believe that addressing the virus will require effective treatments for people who become infected or have been exposed” to the contagion, “complementing the impact vaccines have had in helping quell infections, Chief Scientific Mikael Dolsten explains in a statement. Pfizer’s Officer, President, Worldwide Research, Development and Medical – If successful, we believe this therapy could help stop the virus early, before it has a chance to replicate widely, potentially preventing symptomatic disease in those who have been exposed and inhibiting the onset of infection in others “.
“Given the continuous emergence and evolution of Sars-CoV-2 variants – adds Dolsten – we continue to work to develop new ways in which our experimental oral antiviral candidate could potentially reduce the impact of Covid, not only on patients, but also on their families “.
The Epic-Pep study is a randomized, double-blind, placebo-controlled study and will enroll up to 2,660 healthy adult participants aged 18 years or older. Participants will be randomly assigned to receive the antiviral candidate or an oral placebo twice daily for 5 or 10 days. The primary objective will evaluate the safety and efficacy for the prevention of SARS-CoV-2 infection and its symptoms up to day 14. PF-07321332 (oral protease inhibitor SARS-CoV-2-3CL) showed , according to the note, an “encouraging preclinical profile”, in particular a “potent antiviral activity in vitro” against Sars-CoV-2 and coronaviruses more widely. Results from the Phase 1 clinical trial showed that it is safe and well tolerated.
The Epic Global Program has multiple ongoing clinical trials, including one in Sars-CoV-2 infected patients at high risk of serious illness (and hospitalization or death), which began in July 2021 and another in infected patients who are standard risk (i.e. they have no risk factors for serious disease), which started in August 2021.