FDA Reviews Ensitrelvir as First Oral Pill to Prevent COVID-19 After Exposure

New Post-Exposure Prophylaxis

A new oral medication called ensitrelvir has emerged as the first drug demonstrated to effectively reduce the risk of developing COVID-19 after a person has been exposed to the SARS-CoV-2 virus. The drug is designed for use as post-exposure prophylaxis (PEP), meaning it is taken after contact with an infected individual to prevent the virus from establishing an infection.

According to data from a Phase 3 clinical trial, ensitrelvir showed a 67% reduction in the risk of COVID-19 infection in patients who were treated following exposure. If granted approval by the U.S. Food and Drug Administration (FDA), ensitrelvir would become the first and only oral therapy available for the prevention of the disease in this specific post-exposure window.

Clinical Trial and Regulatory Status

The efficacy of the drug was evaluated in a global, double-blind, randomized, placebo-controlled Phase 3 study known as SCORPIO-PEP. This study specifically focused on the drug's performance as a PEP treatment to determine if it could stop the virus from progressing to a full infection after the initial exposure event.

Shionogi, the developer of the drug, has submitted a New Drug Application (NDA) to the FDA. The company confirmed that the FDA has accepted the NDA for review. While the drug awaits regulatory clearance in the United States, it has already been approved for use in Japan.

Context and Alternative Preventatives

In addition to the progress of ensitrelvir, other preventative methods are being explored. A separate clinical trial has indicated that a common nasal antihistamine spray may also be capable of preventing COVID-19 infections.