Gilead aims for 2025 launch of long-acting PrEP after phase 3 success

In a significant milestone for HIV prevention, Gilead Sciences is poised to introduce a game-changing drug, lenacapavir, following the promising results of its pivotal study. This novel medication, administered twice a year, has demonstrated remarkable efficacy in preventing HIV infections, potentially redefining the market for pre-exposure prophylaxis (PrEP).

Twelve years after the launch of Truvada, the first PrEP medication approved by the FDA, Gilead is on the brink of another historic approval with lenacapavir. The recent study encompassed over 3,000 participants, including cisgender men, transgender men and women, and gender non-binary individuals aged 16 and older from countries like Argentina, Brazil, Mexico, Peru, South Africa, Thailand, and the U.S. The study concluded with only two of the 2,180 participants who took lenacapavir contracting HIV. This resulted in a 96% reduction in HIV infections compared to the background HIV incidence (bHIV).

The PURPOSE 2 study achieved its key endpoints, demonstrating lenacapavir's superiority over both bHIV and Gilead's once-daily Truvada. Following an interim analysis, an independent data monitoring committee confirmed these results. Consequently, the study's blinded phase is concluding, and all patients are being offered open-label lenacapavir. In contrast, nine participants in the Truvada group contracted HIV, underscoring lenacapavir's 89% greater efficacy.

Last year's PURPOSE 1 trial, which focused on cisgender women and adolescent girls in South Africa and Uganda, also yielded unprecedented results. The trial reported zero infections among those taking lenacapavir, leading analysts to predict that the drug could capture a significant share of the PrEP market. Mizuho analyst Salim Syed expressed that lenacapavir is "probably well situated" for this purpose.

Gilead's CEO, Daniel O’Day, highlighted the transformative potential of lenacapavir in a press release, emphasizing its ability to help end the HIV epidemic. He stated that with comprehensive data across multiple study populations, Gilead is working urgently with regulatory, government, public health, and community partners to ensure global access to twice-yearly lenacapavir for PrEP upon approval.

The company plans to initiate global regulatory filings by the end of the year, targeting a 2025 launch. Additionally, Gilead is finalizing contracts for voluntary licensing partnerships to facilitate lenacapavir access in regions with high HIV incidence and limited resources, as part of a broader strategy to expedite approvals in such areas.

Lenacapavir first entered the market in 2022 under the brand name Sunlenca for use with other agents in patients with multidrug-resistant HIV, a group that constitutes 2% of adults living with HIV. With its potential new application as a long-acting PrEP, Gilead aims to significantly impact the market. Chief Commercial Officer Johanna Mercier expressed the company's ambition to "redefine the PrEP market as a whole."

Dr. Colleen Kelly, a principal investigator and professor of medicine at Emory University, noted that adherence to oral PrEP products can be challenging for some individuals. Therefore, the twice-yearly injectable lenacapavir could be a highly impactful intervention for reducing new HIV infections and moving closer to ending the HIV epidemic in the United States.

Analysts at Mizuho have projected lenacapavir's peak sales to reach approximately $4 billion. Meanwhile, GSK is also competing in the long-acting PrEP market with its every-two-month Apretude, launched in 2021, and plans to introduce every-four-month and every-six-month options later in the decade.