Merck’s Covid Drug has 52% Risk Reduction: FDA
An FDA advisory committee briefing document says data show that Merck’s oral antiviral molnupiravir (MOV) was associated with a relative risk reduction of 52% in hospitalization or death compared to placebo in adults with mild-to-moderate Covid-19 and at high risk for progression to severe disease. Committee members are scheduled 11/30 to discuss and vote on the antiviral’s potential emergency use authorization. If authorized, MOV would be a more convenient option for treating Covid patients than the current monoclonal antibodies that require intravenous or subcutaneous administration, the agency notes.
On the safety side, FDA cites “the known and potential risks of MOV, specifically the nonclinical findings of mutagenicity, embryo-fetal toxicity, and impaired bone and cartilage growth, as well as the potential for MOV to enhance SARS-CoV-2 evolution or immune escape.”
The briefing document also says MOV should not be authorized for hospitalized patients because “benefit of treatment with MOV was not observed in participants already hospitalized due to Covid-19... However, should a patient require hospitalization after starting treatment with MOV, the patient may complete the full five-day treatment course at the healthcare provider’s discretion.”
Additionally, FDA says MOV should not be authorized for use during pregnancy because there are no clinical scenarios where the benefit outweighs the risk. It also offers this alternative approach for when the antiviral’s use during pregnancy could be considered: “Under this alternative approach, MOV would not be recommended for use during pregnancy and information would be provided to prescribers regarding the potential risks of use in pregnancy through a Warning and Precaution, however, prescribers could use MOV during pregnancy at their discretion in certain clinical scenarios where the benefits were thought to outweigh the risks.”
FDA’s briefing document also offers another means of optimizing benefit-risk is through patient selection. “The known and potential risks of MOV may be more acceptable in patients with the greater prospect of benefit,” it says, adding that various subgroup analyses were conducted and the literature was reviewed to help better identify patient selection.