By Lisa Hensley, Phd

Recently the results of clinical trials evaluating new treatments for COVID were released. Among these studies was a Phase III trial for a drug named, Molnupiravir. In the trial 762 patients were randomly assigned to receive either the drug or a placebo. Only 28 of the patients who received Molnupiravir required hospitalization compared to 45 in the placebo group and there were 0 deaths observed in the treated group compared to 9 in the placebo group. The data were so encouraging that the independent board charged with monitory the safety as well as the validity and integrity of the study recommended that the study be stopped early and the data made available. Continuation of the study would have been unethical given the promising data observed.

Molnupiravir is a broad spectrum antiviral produced by Merk and Ridgeback Biotherapeutics. The drug was originally discovered at Emory University in 2013 and tested against a variety of different viruses including other coronaviruses, Ebola virus, and respiratory syncytial virus. The work was funded by the National Institutes of Allergy and Infectious Diseases and the Defense Threat Reduction Agency. The drug works by what is termed lethal mutagenesis. The drug is broken down to look like one of the building blocks the virus needs for replication. When the virus uses the look a like building block it creates errors and eventually prevents the virus from replicating.

Currently there are limited options for treatment of COVID during the early stages of disease. There are antibody products, but these require infusions or injections and can only be received in medical centers. Molnupiravir is a pill and must be started within the first five days after the onset of symptoms. Patients taking molnupiravir take four pills two times a day for five days.

Authorities in the UK approved Molnupiravir on November 4th. The FDA is currently reviewing Molnupiravir for the treatment of COVID. Ongoing studies are evaluating the potential for this drug to prevent development of COVID after exposure to the virus. In addition another antiviral, Paxlovid, was submitted by Pfizer for approval by FDA. Like Molnupiravir, patients who tool Paxlovid within three days of symptom onset had were significantly less likely to be hospitalized and no deaths were observed in COVID patients treated with the drug. Approval and widespread availability of the these drugs has the potential to significantly reduce morbidity and mortality and reduce the economic and public health burdens currently being seen across the globe brought about by the pandemic. The potential to use these drugs as post exposure interventions could have even greater impact and bring us one step closer to a return to normalcy.

Sources:

Merck and Ridgeback’s Investigational Oral Antiviral Molnupiravir Reduced the Risk of Hospitalization or Death by Approximately 50 Percent Compared to Placebo for Patients with Mild or Moderate COVID-19 in Positive Interim Analysis of Phase 3 Study

Pfizer Seeks Emergency Use Authorization for Novel COVID-19 Oral Antiviral Candidate | Pfizer

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