TELZIR, known generically as fosamprenavir, is a medication used in the treatment of human immunodeficiency virus (HIV) infection. It belongs to a class of antiretroviral drugs known as protease inhibitors (PIs), which work by inhibiting the protease enzyme that HIV uses to replicate within the body. By blocking this enzyme, TELZIR effectively slows down the progression of the virus, helping to reduce the viral load and increase the immune system's ability to fight off infections. TELZIR is often used in combination with other antiretroviral medications as part of highly active antiretroviral therapy (HAART) to achieve optimal control of HIV. It is important for patients to follow their healthcare provider's instructions closely when taking TELZIR, as adherence to the prescribed regimen is crucial for the effectiveness of the treatment and to prevent the development of drug-resistant strains of the virus.