Pfizer Reports Paxlovid Efficacious in Preventing Severe COVID-19, Mortality

Pfizer reported its investigational therapy, Paxlovid (nirmatrelvir [PF-07321332] tablets and ritonavir tablets), reduced the risk of hospitalization or death by 89% (within 3 days of symptom onset) and 88% (within 5 days of symptom onset) compared to placebo. There were no deaths compared to placebo in non-hospitalized, high-risk adults with COVID-19.

These results stem from the company’s EPIC-HR study, which enrolled 2246 participants and 0.7% of patients who received (nirmatrelvir [PF-07321332] tablets and ritonavir tablets) were hospitalized through Day 28 following randomization (5/697 hospitalized with no deaths), compared to 6.5% of patients who received placebo and were hospitalized or died (44/682 hospitalized with 9 subsequent deaths).

According to the company, relative risk reduction was 94% in patients 65 years of age or older, one of the populations at highest risk for hospitalization or death; 1.1% of patients who received (nirmatrelvir [PF-07321332] tablets and ritonavir tablets) were hospitalized through Day 28 (1/94 hospitalized with no deaths), compared to 16.3% of patients who received placebo (16/98 hospitalized with 6 deaths), with high statistical significance (p<0.0001). In the overall study population through Day 28, no deaths were reported in patients who received Paxlovid as compared to 12 (1.2%) deaths in patients who received placebo.

“This news provides further corroboration that our oral antiviral candidate, if authorized or approved, could have a meaningful impact on the lives of many, as the data further support the efficacy of Paxlovid in reducing hospitalization and death and show a substantial decrease in viral load. This underscores the treatment candidate’s potential to save the lives of patients around the world,” Pfizer CEO Albert Bourla, said.

The company believed it would be efficacious against the Omicron variant. “Emerging variants of concern, like Omicron, have exacerbated the need for accessible treatment options for those who contract the virus, and we are confident that, if authorized or approved, this potential treatment could be a critical tool to help quell the pandemic,” Bourla stated.

The EPIC-HR data have been shared with the US Food and Drug Administration as part of an ongoing rolling submission for Emergency Use Authorization (EUA). No timeline has been set for a discussion for a potential EUA yet.