Merck announced on Friday that it will license seven generic manufacturers to produce a low-cost version of alimatravir, a monthly HIV prevention pill currently undergoing late-stage clinical trials. The move aims to facilitate rapid access to the drug in developing countries if trial data next year confirms its effectiveness.

Alimatravir is designed as a pre-exposure prophylaxis (PrEP) pill taken once a month, offering a potentially transformative tool in the global fight against HIV/AIDS. The drug is being tested among young women in three sub-Saharan African countries, as well as in a separate trial involving transgender people and men who have sex with men across Latin America, Asia, Europe, and Africa.

According to UNAIDS, there were approximately 1.2 million new HIV infections worldwide in 2025. Although preventive treatments exist, access remains limited, especially in resource-limited settings. Efforts to reduce transmission rates have been hampered recently by significant funding cutbacks from key donors, including the United States. A report by the Clinton Health Access Initiative found a 42 percent decline in the initiation of oral PrEP in 2025 across ten high-burden countries in sub-Saharan Africa and Asia compared to the previous year.

Merck’s licensing deal covers 129 low- and middle-income countries and includes four generic producers in India, along with three manufacturers in Uganda, Kenya, and South Africa. The arrangement supports regional drug production, an African Union priority following limited access to COVID-19 vaccines in the continent’s early pandemic phases. Merck will also supply an initial "bridge" stockpile at cost, ahead of generic production and regulatory approval, though the company has not disclosed pricing details.

The drug’s formulation allows low-volume active pharmaceutical ingredient use, making manufacturing potentially cost-effective. Analysts estimate that national health systems could purchase alimatravir for as little as $5 per person annually. This affordability, combined with the ease of monthly oral dosing, may help overcome logistical challenges faced by long-acting injectable alternatives.

Long-acting PrEP options such as lenacapavir, an injectable drug recently introduced in ten African countries, provide nearly complete protection for six months but face distribution challenges amid shrinking donor funds. Critics warn that fragile health systems could struggle with repeated clinic visits necessary for injections. Alimatravir’s monthly oral dosing could allow wider distribution, including through non-clinical settings like schools and salons, potentially increasing access for vulnerable groups, particularly young women.

Advocates cautious about Merck’s announcement emphasize the importance of follow-through, noting prior challenges with new PrEP introductions. “It all sounds good for now, but we will wait to see how it’s put to action,” said Kenneth Mwehonge, executive director of the Coalition for Health Promotion and Social Development in Uganda.

In Latin America, the licensing deal excludes key countries such as Brazil, Colombia, Mexico, Peru, and Chile, all sites for ongoing clinical trials. Merck is negotiating with Brazil’s Oswaldo Cruz Foundation to establish a supply arrangement to improve access there. The region’s middle-income countries have historically faced barriers to affordable access despite public health reliance on such products.

Access issues persist with lenacapavir, which is not yet available in Brazil, despite clinical trials showing its high efficacy. Brazil’s Health Minister Alexandre Padilha criticized the pricing offered by Gilead, the manufacturer of lenacapavir, stating that the public health system cannot afford the cost, even with an offer of about $400 per patient per year, which he said far exceeds the price of generic versions in other countries. Gilead charges approximately $28,000 annually per patient in the United States. Padilha underscored the need for diverse prevention options, particularly for groups like sex workers, who may benefit from discreet, long-acting interventions.

Gilead has affirmed its commitment to expanding access to lenacapavir and is engaging with regional health authorities, including the Pan American Health Organization, to facilitate availability in Latin America and the Caribbean.

The Gates Foundation has invested $100 million in the late-stage trials of alimatravir and plans an additional $80 million to support its clinical development and rollout, reflecting strong optimism in the drug’s potential to enhance HIV prevention efforts globally. Researchers highlight alimatravir’s rapid onset of protection, effective within one hour of dosing, and a grace period of about a week if doses are missed, features that could increase adherence and overall effectiveness.

Merck’s proactive licensing and manufacturing plans mark a notable step in addressing barriers to HIV prevention access, particularly in regions with high disease burdens and constrained health infrastructure. Final trial results next year will determine the full impact of this new intervention on the global HIV response.