Molnupiravir, Merck’s experimental antiviral pill which reduces the risk of hospitalization or death by half, could become the first antiviral pill for treating COVID-19. Remdesivir is the only other antiviral drug approved by FDA, but is administered by IV or injection.
Merck’s molnupiravir could be the breakthrough in treatment that many, especially the developing and underdeveloped countries, have been waiting for. Merck and its partner Ridgeback Biotherapeutics said early results for molnupiravir showed that high-risk adults who took the pill within five days of developing COVID-19 symptoms were about 50% less likely to be hospitalized or die, compared with patients who received a placebo (7.3% vs. 14.1%).
The clinical trial of 775 adults with mild to moderate COVID-19 also had at least one risk factor, such as obesity or heart disease. The drug maker reported that adverse reactions in people who took the pill were similar to people who took a placebo pill.
Jay Grobler, head of infectious disease and vaccines, Merck, said molnupiravir is likely to be effective against known variants of the coronavirus, including the highly transmissible Delta. “Since molnupiravir does not target the spike protein of the virus, which defines the difference between the variants, the drug should be equally effective as the virus continues to evolve,” he said. “Molnupiravir instead targets the viral polymerase, an enzyme needed for the virus to make copies of itself. It is designed to work by introducing errors into the genetic code of the virus.”
Earlier this year, Merck had said that a small, mid-stage trial found that after five days of molnupiravir treatment, none of the patients taking various doses of the drug tested positive for COVID-19, while 24% of placebo patients did have detectable levels. The drugmaker is currently conducting phase III trials of the antiviral and anticipates the study to finish in early November.