Merck’s Antiviral Shows Promise for COVID-19 Prevention

Merck and Ridgeback Biotherapeutics have said their experimental COVID-19 antiviral MK-4482 (molnupiravir) significantly reduced infection after five days of treatment in a clinical trial.

First developed as a treatment for influenza, molnupiravir works as an antiviral by introducing copying errors during viral RNA replication.

Mid-stage trial results from 202 nonhospitalized participants with SARS-CoV-2 infection enrolled in a multicenter phase 2a study showed that, following five days of treatment, zero percent of patients tested positive for the virus vs. 24 percent in the placebo arm, the companies said.

The study also showed a quicker decrease in infectious virus among individuals with early COVID-19 treated with molnupiravir, which “could have important public health implications,” the study’s lead investigator William Fischer said.

Merck is also planning a new phase 3 study evaluating another experimental COVID-19 treatment, MK-7110 (CD24Fc), because a previous late-stage study didn’t gather data from enough participants to support Emergency Use Authorization or approval by the FDA (DID, March 4). ― Jason Scott