Gilead Aspires to Prolong Leadership in HIV Market, Launches Therapeutic Vaccine Quest with Gritstone

On February 1st, Gilead and Gritstone announced a collaboration to develop an HIV therapeutic vaccine. Under the terms of the agreement, Gilead will obtain exclusive rights to develop the vaccine, and Gritstone is eligible to receive up to $785 million.

Human Immunodeficiency Virus (HIV) is responsible for causing Acquired Immunodeficiency Syndrome (AIDS). HIV infects and depletes the body’s immune cells, which leads the person unable to fight infections. It is a potentially life-threatening infection that affects over 38 million people worldwide and around 1.2 million people living with HIV in the US alone.

Current therapies involve daily oral regimens of different antiretroviral drugs. These therapies mitigate viral replication and prevent the development of AIDS, but they do not completely eradicate the virus. There are medications, such a Truvada, that are used to prevent the transmission of the virus but to eliminate this disease and end the HIV epidemic, new medications that can cure HIV are necessary.

From Prevention to Cure

For Gilead, the Pre-Exposure Prophylaxis (PrEP) drug, Truvada, proved to be a blockbuster with almost $3 billion in sales in 2018 and 2019. However, the first generic version of Truvada became available in the US in October 2020. As a result, sales of Truvada were $700 million lower in the third quarter of 2020 than in the same period of time for 2019.

Gilead still has a strong portfolio of HIV antiretroviral and PrEP medication with Biktarvy and Descovy. However, in January, ViiV received authorization for Cabotegravir, a long-lasting injectable medication that is given every two months for the treatment of HIV. Besides, Cabotegravir has been shown to be more effective than Truvada at preventing HIV transmission. This new medication could spell trouble for Gilead.

For this reason, Gilead has invested in the development of multiple treatments to cure HIV. Currently, they have two therapies in Phase 2 clinical trials, two more in Phase 1 trials. With their latest collaboration with Gritstone, Gilead further expands their portfolio of possible cures for HIV.

The Collaboration

Under the agreement, Gilead and Gritstone will develop an HIV-specific therapeutic vaccine that will consist of self-amplifying mRNA and delivered using an adenoviral vector. Gilead will pay $30 million in cash and $30 million in equity investment to Gritstone.

In return, Gilead will conduct a Phase 1 clinical trial with the vaccine and has the option to exclusively license the vaccine for development and commercialization. Gritstone is also eligible for an additional $725 million for clinical, regulatory, and commercial milestones, as well as royalties on net sales.

“While HIV treatment has advanced dramatically over the past three decades, people living with HIV still face a lifetime of therapy,” said Diana Brainard, MD, Senior Vice President, Virology Therapeutic Area, Gilead Sciences.

“Curing HIV remains the ultimate aspiration for Gilead’s HIV research and development efforts. Gritstone’s vaccine technology has the potential to educate the immune system to specifically recognize and destroy HIV-infected cells by leveraging SAM and adenoviral vectors. This, along with our other partnerships and internal programs, reflects Gilead’s commitment to continuing innovation to discover a cure for HIV and bring about an end to the HIV epidemic.”

Related Article: Game-Changing Antiretroviral Regimen from ViiV Receives FDA Approval

References

1. https://ir.gritstoneoncology.com/news-releases/news-release-details/gilead-sciences-and-gritstone-announce-collaboration-utilizing
2. https://www.unaids.org/en/resources/fact-sheet
3. https://www.gilead.com/news-and-press/press-room/press-releases/2020/10/gilead-sciences-announces-third-quarter-2020-financial-results
4. https://www.gilead.com/news-and-press/press-room/press-releases/2020/2/gilead-sciences-announces-fourth-quarter-and-full-year-2019-financial-results

Author

Daniel Ojeda