Used in the treatment of HIV-1 infection, darunavir is a protease inhibitor that works by blocking the activity of the HIV protease enzyme. This action prevents the virus from maturing and producing new infectious particles, thereby reducing the amount of virus in the body. It is typically prescribed in combination with other antiretroviral medications and often boosted with a low dose of ritonavir or cobicistat to enhance its effectiveness. Darunavir is particularly valuable in patients with resistance to other protease inhibitors due to its high genetic barrier to resistance. It helps improve immune function and slows the progression of HIV to AIDS.