Merck (NYSE: MRK) has entered into an agreement with the ADAP Crisis Task Force (ACTF) to help state AIDS Drug Assistance Programs (ADAPs) provide access to its once-daily HIV treatment IDVYNSO (doravirine/islatravir), according to a company press release.

State ADAPs supported more than 250,000 people with HIV in the United States in 2024. The programs primarily serve individuals who are uninsured or underserved.

IDVYNSO received U.S. Food and Drug Administration approval in April 2026 as a two-drug, single-tablet regimen combining 100 mg doravirine and 0.25 mg islatravir. It is indicated for adults with HIV-1 infection who are virologically suppressed on a stable antiretroviral regimen with no history of virologic treatment failure and no known substitutions associated with resistance to doravirine.

"ADAP programs play a critical role in supporting access to treatment for people living with HIV who are uninsured or underserved," said Tim Horn, director of medication access at the National Alliance of State and Territorial AIDS Directors. "We appreciate Merck's continued engagement and its willingness to work collaboratively to help address the critical access challenges facing state ADAP programs."

Conrod Kelly, Merck's U.S. HIV business unit head, said the agreement "reflects our long-standing commitment to working with the ACTF, state ADAPs and the HIV community to strengthen access and help address persistent gaps in care."

The most common adverse reactions reported in clinical trials for IDVYNSO included diarrhea, dizziness, fatigue, abdominal distension, headache, and weight increase. The drug is contraindicated with strong CYP3A enzyme inducers and with lamivudine or emtricitabine.