Merck (MSD) has said that it has seen “encouraging” results in a clinical trial of an anti-viral pill to treat Covid-19 early in the disease’s course, but the drug has failed to help hospitalised patients.

 

The company and its partner Ridgeback Biotherapeutics said they will stop Phase 3 trials on patients who have already been hospitalized with the disease.

 

The final data from the Phase 3 portion (Part 2) of the MOVe-OUT study is estimated to be available in September/ October 2021. 

 

Based on a planned interim analysis of data from the Phase 2, dose-finding portion (Part 1) of two ongoing placebo-controlled Phase 2/3 trials evaluating molnupiravir administered twice a day for five days in outpatients (MOVe-OUT) and hospitalised patients (MOVe-IN) with Covid-19, and from a previously completed Phase 2a dose-ranging study in outpatients, the decision has been made to proceed with the Phase 3 portion (Part 2) of MOVe-OUT in outpatients with Covid-19, evaluating the 800 mg dose of molnupiravir twice daily. 

 

Data from MOVe-IN indicate that molnupiravir is unlikely to demonstrate a clinical benefit in hospitalised patients, who generally had a longer duration of symptoms prior to study entry; therefore, the decision has been made not to proceed to Phase 3.

 

“We continue to make progress in the clinical development of our antiviral candidate molnupiravir. Data from the dose-finding portion of these studies are consistent with the mechanism of action and provide meaningful evidence for the antiviral potential of the 800 mg dose,” said Dr Roy Baynes, senior vice president and head of global clinical development, chief medical officer, Merck Research Laboratories. “Based on the findings of this study we are advancing a Phase 3 trial programme in non-hospitalized patients that strategically leverages our large network of clinical sites to enroll appropriate patients globally.”

 

“We are pleased that molnupiravir continues to show promise as a potential treatment for non-hospitalised patients with COVID-19,” said Wendy Holman, Chief Executive Officer, Ridgeback Biotherapeutics. 

 

“Data from Ridgeback Bio’s EIDD-2801-2003 study (MK-4482-006) coupled with Merck’s MK-4482-002 study provide compelling evidence for the antiviral activity of molnupiravir. We look forward to the initiation and completion of the Phase 3 portion of the MOVe-OUT study.”

 

MOVe-OUT is an ongoing Phase 2/3, randomised, placebo-controlled, double-blind, multi-site study evaluating the efficacy, safety and pharmacokinetics of orally administered molnupiravir in non-hospitalised participants with Covid-19 confirmed using polymerase chain reaction. 

 

The primary efficacy objective of MOVe-OUT is to evaluate the efficacy of molnupiravir compared to placebo as assessed by the percentage of patients who are hospitalised and/or die from the time of randomisation through Day 29. Part 1 of MOVe-OUT enrolled a total of 302 participants, with symptom onset within seven days prior to randomization, who were assigned to receive molnupiravir 200 mg (75), 400 mg (77), or 800 mg (76), or placebo (74).

 

The percentage of patients who were hospitalised and/or died in Part 1 of the MOVe-OUT study was lower in the combined molnupiravir-treated groups versus the placebo arm; the number of events reported are not sufficient to provide a meaningful measure of clinical effect. 

 

Analysis of SARS-CoV-2 in nasopharyngeal and oropharyngeal swabs from patients in both MOVe-OUT and MOVe-IN using quantitative and qualitative polymerase chain reaction, an exploratory endpoint, indicated that molnupiravir inhibits replication of the virus, as demonstrated by a greater decrease from baseline in viral RNA compared to placebo at Day 5 and Day 10, and by a larger proportion of participants with undetectable viral RNA at Day 10 and Day 15 following the end of treatment. The largest overall magnitude of antiviral effect was observed in the 800 mg dose compared with the 200 mg and 400 mg doses. These differences in virology endpoints were more pronounced in participants enrolled < 5 days following symptom onset.

 

Among 299 patients who received at least one dose of study intervention in MOVe-OUT, 6.2% (14/225) of those receiving molnupiravir and 6.8% (5/74) of those receiving placebo reported drug-related adverse events. In MOVe-IN, of 293 patients who received at least one dose of study intervention, 11.0% (24/218) of those treated with molnupiravir and 21.3% (16/75) of those receiving placebo reported drug-related adverse events. To date, safety and laboratory data from MOVe-IN and MOVe-OUT provide no evidence for unexpected findings or trends observed at any of the doses studied. In both trials, no deaths were considered drug-related by the investigators, and there were no drug-related adverse events that led to discontinuation in participants who received molnupiravir. Interim results from both MOVe-IN and MOVe-OUT, including virology findings and pharmacokinetic analyses, have been shared with regulatory authorities and will be presented at an upcoming medical meeting.

 

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. - TradeArabia News Service