Merck, known as MSD outside the United States and Canada, and Ridgeback Biotherapeutics, LP have announced preliminary results from Ridgeback’s Phase 2a randomized, double-blind, placebo-controlled trial to evaluate the safety, tolerability, and efficacy to eliminate SARS-CoV-2 viral RNA of molnupiravir.
Molnupiravir is an investigational oral antiviral agent. The companies on Saturday reported findings on one secondary objective from the Phase 2a study, showing a reduction in time (days) to negativity of infectious virus isolation in nasopharyngeal swabs from participants with symptomatic SARS-CoV-2 infection, as determined by isolation in Vero cell line culture.
These preliminary findings were presented on March 6 during Science Spotlights at the 2021 Conference on Retroviruses and Opportunistic Infections (CROI 2021). Findings from the primary efficacy and safety endpoints and additional secondary objectives will be presented at an upcoming medical meeting.
This multi-centre US study enrolled 202 non-hospitalised adults who had signs or symptoms of COVID-19 within 7 days and confirmed active SARS-CoV-2 infection.
The primary efficacy objective was reduction in time to viral negativity measured by reverse transcriptase polymerase chain reaction (RT-PCR) analysis of nasopharyngeal swabs.
Periodic samples were collected for virologic analysis. Of the 182 participants with an nasopharyngeal swab, 42 per cent (78/182) showed detectable levels of cultured virus at baseline. The full study results remain blinded and will be shared at a later date, as they become available. Other Phase 2 and Phase 2/3 studies are underway.
Of 202 treated participants, no safety signals have been identified and of the 4 serious adverse events reported, none were considered to be study drug related. In addition to the ongoing clinical studies, Merck has conducted a comprehensive nonclinical program to characterize the safety profile of molnupiravir.
“We are very pleased to share our initial Phase 2 infectivity data at this important conference, which remains at the forefront for critical clinical scientific information in infectious diseases,” shared Wendy Painter, Chief Medical Officer of Ridgeback Biotherapeutics. “At a time where there is unmet need for antiviral treatments against SARS-CoV-2, we are encouraged by these preliminary data.
“The secondary objective findings in this study, of a quicker decrease in infectious virus among individuals with early COVID-19 treated with molnupiravir, are promising and if supported by additional studies, could have important public health implications, particularly as the SARS-CoV-2 virus continues to spread and evolve globally,” noted William Fischer, lead investigator of the EIDD-2801 2003 study and Associate Professor of Medicine, Division of Pulmonary Diseases and Critical Care Medicine at the University of North Carolina School of Medicine.