KENILWORTH, New Jersey – (COMMERCIAL THREAD) – Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced the results of a Phase 2a clinical trial evaluating the safety, tolerability and pharmacokinetics (PK) of six monthly oral doses, over 24 weeks, of islatravir, the company’s experimental nucleoside reverse transcriptase translocation inhibitor, compared to placebo for pre-exposure prophylaxis (PrEP) of HIV-1 infection in adults at low risk of contracting HIV-1. After 24 weeks, oral islatravir once a month was generally well tolerated compared to placebo. Most of the adverse events (AEs) were mild and there were no serious drug-related AEs in people who received islatravir. Islatravir levels in peripheral blood mononuclear cells (PBMCs) also remained above the predefined PK threshold of effectiveness for PrEP at the two doses studied (60 mg and 120 mg) eight weeks after the last dose of l ‘study. This data was shared as a last minute oral presentation during the 11^e International AIDS Society Conference on HIV Science (IAS 2021) and follow the interim analysis that was present earlier this year at the 2021 HIV Research for Prevention (HIVR4P 2021) virtual conference.

“The 24-week review of investigational oral islatravir, once a month, not only builds on the pharmacokinetic data that we have already seen, but also provides encouraging support for the safety and tolerability profile of this drug. HIV-1 PrEP protocol, ”said Dr. Joan Butterton, vice president, global clinical development, infectious diseases, Merck Research Laboratories. “As part of our commitment to understanding the potential of our HIV drugs in a wide range of patients, we have focused on recruiting diverse patient populations at risk for HIV, including women, who have HIV. one of the most important unmet HIV prevention needs.

Islatravir is currently being evaluated under various dosage schedules, both for the treatment of HIV-1 infection in combination with other antiretrovirals and for the prevention of HIV-1 infection as monotherapy. An overview of the program for the development of treatment and prevention with islatravir is available here, which includes our two Phase 3 IMPOWER trials evaluating islatravir as oral PrEP once a month in various populations of people who may benefit from additional HIV-1 prevention options.

Results of the phase 2a oral study for investigational islatravir

In the multicenter, phase 2a, randomized, double-blind, parallel, placebo-controlled trial (NCT04003103) in adults at low risk of HIV-1 infection, participants were assigned to randomly (2: 2: 1) to one of the three monthly oral treatment groups: islatravir 60 mg, islatravir 120 mg, or placebo. Participants received monthly oral doses of islatravir or placebo over a 24-week blinded treatment period, followed by 12-week blinded follow-up in all groups and blinded follow-up of 32 weeks in the islatravir groups to characterize the terminal elimination phase. Outcome measures for safety, tolerability and pharmacokinetics will be analyzed through week 68.

Of the 242 participants randomized in this 24-week analysis, which concludes the dosing portion of the study, 92% (n = 222/242) completed dosing and 8% (n = 20/242) discontinued dosing. study intervention before week 24. Less than 1% (n = 2) of participants dropped out due to an AE. Of the total participants, 67.4% (n = 163/242) were female, 52.9% (n = 128/242) were white, 41.7% (n = 101/242) were black or afro -Americans and 14.9% (n = 36/242) were Hispanic or Latino. Nonblind safety data showed that the two doses of islatravir were generally well tolerated compared to placebo over 24 weeks and that most AEs were mild (73.5%). The most common AEs (occurring >5% of participants) in the islatravir 60 mg, islatravir 120 mg and placebo groups respectively were headache (10.3% [n=10/97], 9.3% [n=9/97] and 4.2% [n=2/48]), diarrhea (5.2% [n=5/97], 5.2% [n=5/97] and 8.3% [n=4/48]) and nausea (5.2% [n=5/97]), 7.2% [n=7/97] and 4.2% [n=2/48]). There were no serious drug-related AEs in people who received islatravir. The study recruited a population at low risk of HIV infection, as evidenced by the absence of confirmed HIV infection occurring during the treatment period.

Pharmacokinetic analysis has shown that trough concentrations (the lowest level between doses) of islatravir triphosphate in PBMCs after monthly doses of 60 mg or 120 mg continue to remain above the predefined PK threshold for the patient. 0.05 pmol / 10 HIV-1 prophylaxis⁶ PBMCs and were maintained for eight weeks after the last dose of islatravir.

About islatravir (MK-8591)

Islatravir (MK-8591) is the investigational inhibitor of Merck’s nucleoside reverse transcriptase translocation being evaluated in clinical trials for the treatment of HIV-1 infection in combination with other antiretrovirals, including the ILLUMINATE clinical trials program for once-daily therapy. Islatravir is also being studied for the pre-exposure prophylaxis (PrEP) of HIV-1 infection as a single agent across a variety of formulations, including IMPOWER clinical trials evaluating an oral regimen. once a month.

Our commitment against HIV

For more than 35 years, Merck has been engaged in scientific research and discovery (R&D) on HIV. Today, we are developing a series of antiviral options designed to help people manage HIV and protect people from HIV, with the goal of reducing the growing burden of infection around the world. We remain committed to working hand-in-hand with our partners in the global HIV community to address the complex challenges that hamper progress towards ending the epidemic.

About Merck

For 130 years, Merck, known as MSD outside of the United States and Canada, has been inventing for life, providing drugs and vaccines for many of the world’s most difficult diseases as part of our mission to save and improve lives. We demonstrate our commitment to patients and the health of the population by increasing access to health care through broad policies, programs and partnerships. Today, Merck continues to be at the forefront of research to prevent and treat diseases that threaten humans and animals – including cancer, infectious diseases such as HIV and Ebola, and emerging animal diseases – as we aspire to be the premier research-intensive biopharmaceutical company. in the world. For more information visit www.merck.com and connect with us on Twitter, Facebook, Instagram, Youtube and LinkedIn.

Forward-looking statement by Merck & Co., Inc., Kenilworth, NJ, United States

This press release from Merck & Co., Inc., Kenilworth, NJ, United States (the “Company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act. from 1995. These statements are based on the current beliefs and expectations of the management of the company and are subject to significant risks and uncertainties. There can be no assurance with respect to products in the pipeline that the products will receive the necessary regulatory approvals or prove to be commercially successful. If the underlying assumptions prove to be incorrect or if risks or uncertainties materialize, actual results may differ materially from those stated in forward-looking statements.

Risks and uncertainties include, but are not limited to, general industry conditions and competition; general economic factors, including fluctuations in interest rates and exchange rates; the impact of the global novel coronavirus disease (COVID-19) epidemic; the impact of pharmaceutical industry regulation and health care legislation in the United States and globally; global trends towards containing health care costs; technological advances, new products and patents obtained by competitors; challenges inherent in developing new products, 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 patents and other corporate protections for innovative products; and exposure to litigation, including patent litigation, and / or regulatory actions.

The company does not undertake 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 forward-looking statements can be found in the company’s 2020 annual report on Form 10-K and other documents filed by the company with the Securities. and Exchange Commission (SEC) available from the SEC. Website (www.sec.gov).