Merck and Ridgeback Biotherapeutics Provide Update on Progress of Clinical Development Program for Molnupiravir, an Investigational Oral Therapeutic for the Treatment of Mild-to-Moderate COVID-19 - Seite 3

Final data from the Phase 3 portion (Part 2) of the MOVe-OUT study is estimated to be available in September/ October 2021. Merck currently anticipates that, pending favorable results from MOVe-OUT, the earliest possible submission for an Emergency Use Authorization for molnupiravir will be in the second half of 2021. Merck and Ridgeback Biotherapeutics plan to share further findings from the ongoing molnupiravir development program with regulatory agencies as they become available.

In addition, Merck plans to initiate a clinical program to evaluate molnupiravir for post- exposure prophylaxis in the second half of 2021.

About the MOVe-OUT study design

MOVe-OUT (MK-4482-002) is a Phase 2/3, randomized, placebo-controlled, double-blind, multi-site study evaluating the efficacy, safety and pharmacokinetics of orally administered molnupiravir in non-hospitalized participants at least 18 years of age with laboratory confirmed COVID-19 and symptom onset within seven days prior to randomization. The trial plans to enroll a total of 1850 participants with mild or moderate COVID-19. The Phase 2 portion of the trial enrolled 302 participants randomized 1:1:1:1 to receive molnupiravir 200 mg, 400mg, 800mg or placebo twice daily for 5 days. The primary efficacy objective is to evaluate efficacy of molnupiravir compared to placebo as assessed by the percentage of participants who are hospitalized and/or die during the period from randomization through Day 29. Exploratory endpoints supporting dose selection for Phase 3 portion (Part 2) include change from baseline in SARS-CoV-2 RNA plasma levels and percentage of participants with undetectable SARS-CoV-2 RNA various time points, viral RNA mutation rate as assessed by comparison of baseline and post-baseline virus sequencing and pharmacokinetic data (eg, Ctrough, Cmax, tmax, t1/2, AUC0-12). Following the completion of Part 1 the inclusion criteria for MOVe-OUT were amended reducing the allowable symptom duration for enrollment to < 5 days and increasing enrollment for those considered high risk for poor COVID-19 outcomes (e.g., older patients and those with obesity and diabetes). For further information regarding the trial please visit clinicaltrials.gov.