Gilead, Merck Unite to Contest ViiV’s Cabenuva with Long-Acting HIV Therapy

On March 15th, Gilead and Merck announced they would collaborate to develop a long-lasting HIV treatment. They will co-develop and co-commercialize treatments that combine Gilead’s lenacapavir and Merck’s islatravir into a long-acting two-drug regimen. After the announcement, Gilead’s stock rose by 1.09%, and Merck’s rose by 1.77%.

For the over 38 million people living with HIV worldwide, there is no current medication that can eradicate HIV. They depend on daily doses of antiretroviral drugs, which can suppress viral replication and prevent the development of AIDS. One of the companies that dominated the HIV therapeutics market was Gilead.

However, Gilead has been under pressure to revamp its HIV treatment portfolio. Particularly because the patent for their blockbuster Pre-Exposure Prophylaxis (PrEP) drug, Truvada, has expired, and the emergence of the long-acting antiretroviral Cabenuva, which was developed by ViiV Healthcare, a company primarily owned by GSK.

Gilead has been preparing by testing the long-term efficacy of their own therapies such as Biktarvy and lenacapavir. Additionally, they started a collaboration to develop HIV-specific therapeutics vaccines with Gritstone, and they have several of their therapies in Phase 1 and 2 clinical trials.

The Collaboration

Together with Merck, Gilead aims to develop long-acting oral and injectable formulations of lenacapavir, an investigational capsid inhibitor developed by Gilead, and islatravir, an investigational nucleoside reverse transcriptase translocation inhibitor developed by Merck. Additional formulations may be added and developed as mutually agreed.

The collaboration consists of sharing the cost of development and commercialization on a 60% Gilead, 40% Merck basis. For the oral formulations, the companies agreed to:

• Gilead will lead commercialization in the U.S., and Merck will focus on the EU and the rest of the world.
• Profits will be split on a 50/50 basis until the net product sales reach $2 billion a year. Profits that pass that threshold will be split 65% Gilead and 35% Merck.

For injectable formulations:

• Merck will lead commercialization in the U.S., and Gilead will lead the efforts in the EU and the rest of the world.
• Profits will be split 50/50 until net sales reach $3.5 billion a year. Profits above that, the same 65/35 split as in oral formulations will take place.

Additionally, both companies have the option to license investigational oral integrase inhibitor from the other company after such inhibitor has completed Phase 1 clinical trials. If either of them chose to exercise this option, both companies would split development costs and revenues unless the non-exercising company opts-out.

“Through this agreement with Merck, Gilead is reinforcing its long-term role in transforming HIV care,” said Daniel O’Day, Chairman, and Chief Executive Officer, Gilead Sciences. “Our work in HIV over the past decades has been shaped by listening to people living with HIV and the physicians who treat them. Now we are taking the same approach with long-acting therapies, combining the most advanced science from both companies to accelerate progress.”

If successful, Gilead and Merck could become formidable opponents to ViiV’s once every two months treatment Cabenuva.

Related Article: Gilead Reports FDA-Approved HIV Therapy Demonstrates Long-Term Efficacy

Author

Daniel Ojeda

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