Cobicistat is a pharmaceutical compound used as a pharmacokinetic enhancer in the treatment of HIV infection. Developed by Gilead Sciences, it works by inhibiting enzymes such as CYP3A that metabolize certain antiretroviral drugs, thereby increasing their effectiveness. It does not have antiviral activity on its own but is commonly combined with drugs like Atazanavir or Darunavir. Cobicistat was approved by the U.S. Food and Drug Administration in 2012 and introduced as part of fixed-dose combination therapies, offering an alternative to ritonavir with fewer side effects and drug interactions.