The U.S. Food and Drug Administration (FDA) has approved a new first-of-its-kind medication for patients living with type 1 HIV. The Dec 22, 2022 announcement stated that Gilead Sciences’ drug Sunlenca (lenacapavir) is approved to treat HIV patients that “cannot be successfully treated with other available treatments due to resistance, intolerance, or safety considerations.”

Human immunodeficiency virus (HIV) comes in two variants, HIV type 1 and HIV type 2. Both types are viruses that attack the immune system by inserting their own DNA into the nucleus of host cells. HIV-1 is the most common form and can be acquired through contact with bodily fluids, including blood, breast milk, and sexual fluids. While HIV-1 can be managed and suppressed to undetectable levels, there is currently no cure for HIV.

Sunlenca is part of a new class of drugs called capsid inhibitors. Capsid inhibitors function by blocking the HIV-1 virus’ protein shell, known as the capsid. With the capsid blocked, multiple essential phases of the virus’ lifecycle cannot be completed, and the number of HIV-1 viruses in the patient’s body decreases. Sunlenca is initially given as an oral tablet and subcutaneous injection, followed by upkeep injections every six months.

During clinical trials, Sunlenca was given to patients who had HIV infections that were resistant to multiple other classes of HIV medications. When administered in conjunction with antiretroviral drugs, 87.5% of patients who received Sunlenca achieved the targeted level of HIV-1 virus compared to 16.7% of patients who received a placebo. After 26 weeks of taking Sunlenca with antiretroviral drugs, 81% of study participants reached undetectable levels of HIV-1. After one year, 83% of participants maintained undetectable levels of the virus.

Debra Birnkrant, M.D., director of the Division of Antivirals in the FDA’s Center for Drug Evaluation and Research, stated “Today’s approval ushers in a new class of antiretroviral drugs that may help patients with HIV who have run out of treatment options,” adding that the availability of drugs like Sunlenca may help patients with type 1 HIV live “longer, healthier lives.”