Gilead's Lenacapavir: Twice-Yearly HIV PrEP Could Be a $5B Product

Gilead Sciences already dominates HIV treatment with Biktarvy and Descovy. Lenacapavir (Yeztugo) is now making Gilead the leader in HIV prevention — a market that was barely tapped before approval.

The drug

Lenacapavir is a first-in-class capsid inhibitor — it targets the HIV capsid protein, disrupting multiple stages of the viral life cycle. It’s administered as a subcutaneous injection every six months.

For HIV PrEP (pre-exposure prophylaxis), lenacapavir is the first twice-yearly preventive option. Current PrEP alternatives require daily pills (Truvada, Descovy) or bimonthly injections (Apretude). A six-month injection solves the adherence problem that limits PrEP uptake.

The data

The Purpose 2 trial enrolled 3,200 participants at high risk of HIV infection. Results:

• 0 infections in the lenacapavir group (n = 2,184)
• Standard of care comparison: 99% relative risk reduction vs. background incidence
• Safety: No serious adverse events related to the drug

The Purpose 1 trial (announced in 2024) showed the same result: 0 infections in 2,134 women. Two trials, 5,300+ participants, 0 infections. The efficacy is unprecedented.

Approval and market

The FDA approved Yeztugo (lenacapavir) for PrEP on June 18, 2025, making it the first and only twice-yearly HIV prevention option. The approval was based on the Purpose 1 and Purpose 2 trials. Lenacapavir is also approved for treatment of multi-drug-resistant HIV in combination with other antiretrovirals.

Global PrEP uptake is low. Of the 1.2 million people who could benefit from PrEP in the US, only ~300,000 are on it. The barriers: daily pill fatigue, stigma, and access. A twice-yearly injection removes the adherence barrier. Peak PrEP sales estimates range from $3–5 billion globally.

Gilead is also running the STAR study to test lenacapavir as a twice-yearly treatment (not just prevention) for people who already have HIV. That’s a separate $5B+ opportunity.

The risk

The science is strong. The risk is commercial:

1. Pricing: Lenacapavir is expensive to manufacture. If Gilead prices it too high, access programs and generics manufacturers (in developing countries) could limit revenue.
2. Access: Gilead has committed to licensing lenacapavir to generic manufacturers for 120 low-income countries. This is good for public health but limits the revenue model. Several African countries (Mozambique, Namibia, Kenya, Uganda) and Brazil already approved lenacapavir for PrEP in January 2026.
3. Competition: ViiV Healthcare’s cabotegravir (Apretude) is a bimonthly PrEP injection. Lenacapavir’s twice-yearly dosing is better, but Apretude has a head start.

What we’re watching

1. BIC/LEN approved as Bixlenvo (August 27, 2026): Gilead’s NDA for a once-daily single-tablet regimen combining bictegravir with lenacapavir was approved August 27, 2026 as Bixlenvo — the first and only once-daily single-tablet regimen for virologically suppressed adults with HIV on complex regimens. See our Bixlenvo approval coverage.
2. Once-weekly oral lenacapavir (PDUFA February 2, 2027): Gilead has filed an sNDA for a 300-mg weekly oral formulation of Yeztugo for PrEP. If approved, this would be the first long-acting oral PrEP option.
3. Commercial uptake: Early prescription data for the twice-yearly injection will signal whether the convenience advantage is converting patients from daily PrEP.
4. Access deals: Gilead’s licensing agreements for developing countries will affect both public perception and revenue.

Gilead’s stock is up 4% YTD, and lenacapavir is a key growth story beyond the oncology portfolio. The HIV franchise isn’t going away — it’s evolving.