Reyataz is a protease inhibitor. When viral RNA gets transcribed into DNA and DNA gets translated into proteins, the viral proteins produced are joined together, forming a long polypeptide sequence. In order for the different viral proteins to function properly, they must first separate from the long polypeptide sequence. HIV proteases take over the task of breaking the long polypeptide into functional proteins; which can then assemble together with RNA to form new viruses. Reyataz functions by inhibiting HIV proteases and thus preventing the formation of functional viral proteins.