Merck Provides Update on Phase 3 MOVe-AHEAD Trial Evaluating LAGEVRIO™ (molnupiravir) for Post-exposure Prophylaxis for Prevention of COVID-19

RAHWAY, N.J.--()--Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced that LAGEVRIO™ (molnupiravir) did not demonstrate a statistically significant reduction in the risk of COVID-19 following household exposure to another individual with COVID-19. The Phase 3 MOVe-AHEAD trial evaluated people who did not have COVID-19 at baseline (confirmed by a negative baseline SARS-CoV-2 test and no signs and symptoms) but lived with someone who was recently diagnosed with COVID-19. In the primary endpoint of participants who did not have evidence of SARS-CoV-2 infection at baseline (confirmed by a negative SARS-CoV-2 test), the LAGEVRIO treated group was observed to be 23.6% less likely than those who received placebo to develop COVID-19 through Day 14 (a positive post-baseline SARS-CoV-2 test with evidence of signs and symptoms); the primary endpoint was not met. The safety profile of LAGEVRIO in this trial was generally consistent with that observed in previously reported clinical studies and post-authorization experience in the treatment of COVID-19. Merck intends to submit full results from this study for presentation at a scientific meeting or for publication.

Results from this post-exposure prevention study are scientifically interesting as we continue to learn more about COVID-19. We are grateful to the MOVe-AHEAD trial participants and investigators for their contributions to this study,” said Dr. Dean Y. Li, president, Merck Research Laboratories. “This was not a treatment study and these results do not impact the efficacy and safety data observed in our Phase 3 MOVe-OUT trial for the treatment of mild-to-moderate COVID-19. We remain focused on our ongoing efforts to bring LAGEVRIO as treatment to appropriate high-risk patients with COVID-19 where its use is authorized or approved, as well as to further study the ways it may benefit patients with other infectious diseases, such as RSV.”

LAGEVRIO is approved or authorized in several markets including the U.S., United Kingdom, Australia, China and Japan, for the treatment of certain adults who have been diagnosed with COVID-19. See additional information on the authorized use of LAGEVRIO in the U.S. below. LAGEVRIO is not authorized for pre-exposure or post-exposure prophylaxis for prevention of COVID-19.

About the MOVe-AHEAD Study

MOVe-AHEAD (MK-4482-013) (NCT04939428) was a Phase 3 multicenter, randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of orally administered LAGEVRIO (molnupiravir) compared to placebo in preventing the spread of SARS-CoV-2, the virus that causes COVID-19, within households. The trial enrolled over 1,500 participants who were randomized to receive either LAGEVRIO (800 mg) or placebo orally every 12 hours for five days. The study enrolled participants who were at least 18 years of age and resided in the same household with someone who received a positive test for SARS-CoV-2, had at least one sign or symptom of COVID-19 and had not had those signs and symptoms for more than five days. Participants were not eligible for the trial if they received the first dose of a COVID-19 vaccine more than seven days prior to enrollment, previously had COVID-19 within the past six months or were showing any signs or symptoms of COVID-19.

The primary endpoints of the trial included percentage of participants who have undetectable SARS-CoV-2 in baseline nasopharyngeal (NP) swabs and develop COVID-19 through Day 14, percentage of participants with an adverse event and percentage of participants who discontinued study intervention due to an adverse event.

The trial was conducted globally in countries including Argentina, Brazil, Bulgaria, Colombia, Egypt, France, Guatemala, Hungary, Japan, Kenya, Mexico, Philippines, Romania, Russia, South Africa, Thailand, Turkey, Ukraine, and the United States.

About Merck’s Global Efforts to Accelerate Access to LAGEVRIO (molnupiravir) Following Regulatory Authorizations or Approvals

Global access has been a priority for Merck and Ridgeback Biotherapeutics LP, a biotechnology company focused on emerging infectious diseases, since the inception of their LAGEVRIO collaboration. The companies are committed to providing timely access to LAGEVRIO globally through our comprehensive supply and access approach, which includes:

Supply: Patients around the world have received approximately 4 million courses of LAGEVRIO. Merck has supplied LAGEVRIO to more than 40 markets worldwide.

Voluntary licenses: As part of its commitment to widespread global access, Merck granted voluntary licenses (VLs) to generic manufacturers and to the Medicines Patent Pool to make generic molnupiravir available in more than 100 low- and middle-income countries following approvals or emergency authorization by local regulatory agencies. Through our voluntary licensing agreements with generic manufacturers, more than 5 million courses of generic molnupiravir have been delivered to 22 markets through December 2022. Additionally, Hetero Labs, Ltd. has received WHO prequalification, an important step in enabling broader access to molnupiravir.

UNICEF: To supplement the supply from licensed generic manufacturers and bridge to the availability of WHO prequalified generic supply, Merck entered into an agreement with UNICEF to allocate up to 3 million courses of LAGEVRIO to facilitate timely supply to low- and middle-income countries. Merck has also committed 2 million patient courses of LAGEVRIO, available to USAID at Merck’s best access price to increase access in lower-income countries.

Product donation: Merck has donated 100,000 courses of therapy to Direct Relief, a global humanitarian aid organization, for distribution to refugees, including 50,000 courses of therapy for people affected by the invasion of Ukraine.

Purchase and supply agreements: Merck entered into a procurement agreement with the U.S. government under which the company supplied approximately 3.1 million courses of LAGEVRIO to the U.S. government, upon Emergency Use Authorization from the U.S. Food and Drug Administration. The U.S. Department of Health and Human Services (HHS) has created a Test-to-Treat locator to help identify pharmacies and community health centers across the nation where people can get tested for COVID-19 and receive appropriate treatments, as needed.

Merck has also entered into additional advance purchase and supply agreements for LAGEVRIO with governments of more than 40 markets worldwide and is currently in discussions with additional governments. Merck is implementing a tiered-pricing approach based on World Bank country income criteria to reflect countries’ relative ability to finance their health response to the pandemic.

Responding to global needs with urgency: In September 2022, Merck announced a cooperation framework agreement with Sinopharm Group Co. Ltd., under which Merck granted distribution and exclusive import rights for LAGEVRIO to Sinopharm following authorization. To date, we have shipped more than one million courses of LAGEVRIO to China, with additional shipments planned.

Authorized Use of LAGEVRIO (molnupiravir) in the U.S.

The U.S. Food and Drug Administration (FDA) has issued an EUA for the emergency use of the unapproved product LAGEVRIO, a nucleoside analogue that inhibits SARS-CoV-2 replication by viral mutagenesis, for the treatment of adults with a current diagnosis of mild-to-moderate coronavirus disease 2019 (COVID-19) who are at high risk for progression to severe COVID-19, including hospitalization or death, and for whom alternative COVID-19 treatment options approved or authorized by FDA are not accessible or clinically appropriate. LAGEVRIO is not FDA-approved for any use, including the treatment of COVID-19.

The emergency use of LAGEVRIO is only authorized for the duration of the declaration that circumstances exist justifying the authorization of the emergency use of drugs and biological products during the COVID-19 pandemic under Section 564(b)(1) of the Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 360bbb-3(b)(1) unless the declaration is terminated or authorization revoked sooner.

LAGEVRIO is not authorized for use in patients less than 18 years of age or for initiation of treatment in patients hospitalized due to COVID-19. Benefit of treatment with LAGEVRIO has not been observed in subjects when treatment was initiated after hospitalization due to COVID-19. LAGEVRIO is not authorized for use for longer than five consecutive days. LAGEVRIO is not authorized for pre-exposure or post-exposure prophylaxis for prevention of COVID-19. LAGEVRIO may only be prescribed for an individual patient by physicians, advanced practice registered nurses, and physician assistants that are licensed or authorized under state law to prescribe drugs in the therapeutic class to which LAGEVRIO belongs (i.e., anti-infectives).

Selected Safety Information for LAGEVRIO


No contraindications have been identified based on the limited available data on the emergency use of LAGEVRIO authorized under this EUA.

Warnings and Precautions

There are limited clinical data available for LAGEVRIO. Serious and unexpected adverse events may occur that have not been previously reported with LAGEVRIO use.

LAGEVRIO is not recommended for use during pregnancy. Based on findings from animal reproduction studies, LAGEVRIO may cause fetal harm when administered to pregnant individuals. There are no available human data on the use of LAGEVRIO in pregnant individuals to evaluate the risk of major birth defects, miscarriage or adverse maternal or fetal outcomes.

LAGEVRIO is authorized to be prescribed to a pregnant individual only after the healthcare provider has determined that the benefits would outweigh the risks for that individual patient. If the decision is made to use LAGEVRIO during pregnancy, the prescribing healthcare provider must document that the known and potential benefits and the potential risks of using LAGEVRIO during pregnancy were communicated to the pregnant individual.

There is a pregnancy registry that monitors pregnancy outcomes in individuals exposed to LAGEVRIO during pregnancy. The prescribing healthcare provider must document that a pregnant individual was made aware of the pregnancy registry at or 1-800-616-3791. Pregnant individuals exposed to LAGEVRIO or their healthcare providers can also report the exposure by contacting Merck Sharp & Dohme LLC, Rahway, NJ USA at 1-877-888-4231.

Advise individuals of childbearing potential of the potential risk to a fetus and to use an effective method of contraception correctly and consistently during treatment with LAGEVRIO and for 4 days after the final dose.

Prior to initiating treatment with LAGEVRIO, assess whether an individual of childbearing potential is pregnant or not, if clinically indicated.

Hypersensitivity reactions, including anaphylaxis, have been reported with LAGEVRIO. If signs and symptoms of a clinically significant hypersensitivity reaction or anaphylaxis occur, immediately discontinue LAGEVRIO and initiate appropriate medications and/or supportive care.

LAGEVRIO is not authorized for use in patients less than 18 years of age because it may affect bone and cartilage growth. The safety and efficacy of LAGEVRIO have not been established in pediatric patients.

Adverse Reactions

The most common adverse reactions occurring in ≥1% of subjects in the LAGEVRIO treatment group in the Phase 3 double-blind MOVe-OUT study were diarrhea (2% versus placebo at 2%), nausea (1% versus placebo at 1%), and dizziness (1% versus placebo at 1%) all of which were Grade 1 (mild) or Grade 2 (moderate).

Serious adverse events occurred in 7% of subjects receiving LAGEVRIO and 10% receiving placebo; most serious adverse events were COVID-19 related. Adverse events leading to death occurred in 2 (<1%) of the subjects receiving LAGEVRIO and 12 (2%) of subjects receiving placebo.

Drug Interactions

No drug interactions have been identified based on the limited available data on the emergency use of LAGEVRIO. No clinical drug-drug interaction trials of LAGEVRIO with concomitant medications, including other treatments for mild to moderate COVID-19, have been conducted.


There are no data on the presence of molnupiravir or its metabolites in human milk. It is unknown whether molnupiravir has an effect on the breastfed infant or effects on milk production. Based on the potential for adverse reactions in the infant from LAGEVRIO, breastfeeding is not recommended during treatment with LAGEVRIO and for 4 days after the final dose. A lactating individual may consider interrupting breastfeeding and may consider pumping and discarding breast milk during treatment and for 4 days after the last dose of LAGEVRIO.

Males of Reproductive Potential

Nonclinical studies to fully assess the potential for LAGEVRIO to affect offspring of treated males have not been completed. Advise sexually active individuals with partners of childbearing potential to use a reliable method of contraception correctly and consistently during treatment and for at least 3 months after the last dose of LAGEVRIO. The risk beyond three months after the last dose of LAGEVRIO is unknown.

Required Reporting for Serious Adverse Events and Medication Errors

The prescribing healthcare provider and/or the provider’s designee is/are responsible for mandatory reporting of all serious adverse events and medication errors potentially related to LAGEVRIO within 7 calendar days from the healthcare provider’s awareness of the event.

Submit adverse event and medication error reports, using FDA Form 3500, to FDA MedWatch using one of the following methods:

In addition, please provide a copy of all FDA MedWatch forms to: Merck Sharp & Dohme LLC, Rahway, NJ USA by: Fax: 215-616-5677 E-mail:

About LAGEVRIO (molnupiravir)

LAGEVRIO (molnupiravir) (MK-4482) is an investigational, orally administered nucleoside analog that inhibits the replication of SARS-CoV-2, the causative agent of COVID-19.

Merck and Ridgeback’s “orange COVID-19 pill” is a Swedish Orange opaque capsule with the Merck corporate logo and “82” printed in white ink, available in certain markets as LAGEVRIO.

Molnupiravir was invented at Emory University. Drug Innovation Ventures at Emory (DRIVE), LLC, which was formed by Emory to develop early-stage drug candidates for viral diseases of global concern, advanced molnupiravir through IND submission. Emory/DRIVE received some research funding from the U.S. Department of Defense and the U.S. National Institutes of Health. LAGEVRIO is being developed by Merck in collaboration with Ridgeback Biotherapeutics. Ridgeback received an upfront payment from Merck and also is eligible to receive contingent payments dependent upon the achievement of certain developmental and regulatory approval milestones. Any profits from the collaboration will be split between the partners equally. Since licensed by Ridgeback, all funds used for the development of LAGEVRIO have been provided by Merck and Ridgeback.

LAGEVRIO was evaluated in MOVe-OUT, a global Phase 3, randomized, placebo-controlled, double-blind, multi-site study of non-hospitalized adult patients with symptomatic, laboratory-confirmed mild to moderate COVID-19 and at least one risk factor associated with poor disease outcomes. The Phase 3 portion of the MOVe-OUT trial was conducted globally in more than 170 sites in locations including Argentina, Brazil, Canada, Chile, Colombia, Egypt, France, Germany, Guatemala, Israel, Italy, Mexico, Philippines, Poland, Russia, South Africa, Spain, Sweden, Taiwan, Ukraine, the United Kingdom and the United States. For further information about the MOVe-OUT trial, please visit

LAGEVRIO is being studied in other diseases beyond coronaviruses. Early work on additional programs has begun, and a study evaluating LAGEVRIO for RSV (NCT05559905) is recruiting participants.

About Merck

At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy future for all people and communities. For more information, visit and connect with us on Twitter, Facebook, Instagram, YouTube and LinkedIn.

Forward-Looking Statement of Merck & Co., Inc., Rahway, N.J., USA

This news release of Merck & Co., Inc., Rahway, N.J., USA (the “company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline candidates that the candidates will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements.

Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of the global outbreak of novel coronavirus disease (COVID-19); the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company’s patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions.

The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company’s Annual Report on Form 10-K for the year ended December 31, 2021 and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site (

Please see the Molnupiravir FDA Letter of Authorization at, Fact Sheet for Healthcare Providers, including Mandatory Requirements for Administration of Molnupiravir under Emergency Use Authorization, at and Fact Sheet for Patients and Caregivers at


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Release Summary

Merck Provides Update on Phase 3 MOVe-AHEAD Trial Evaluating LAGEVRIO™ (molnupiravir) for Post-exposure Prophylaxis for Prevention of COVID-19



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Julie Cunningham
(617) 519-6264
Deb Wambold
(215) 779-2234

Peter Dannenbaum
(908) 740-1037
Damini Chokshi
(908) 740-1807