Rationale and experience with reverse transcriptase inhibitors and protease inhibitors.

The majority of antiretroviral agents used in the treatment of HIV are targeted at the HIV reverse transcriptase (RT) enzyme. In a continuing effort to develop more effective antiviral regimens, drugs that target other specific enzymes in the virus replication cycle are under development. A promising new class of drugs is the protease inhibitors. These antiviral agents are potent and highly specific, giving excellent inhibition of viral replication. Unfortunately, the high level of inhibition may not be maintained in vivo because of the rapid emergence of resistance to these agents when they are used as monotherapy. However, the combination of protease inhibitors with reverse transcriptase inhibitors may represent a major advance in the treatment of HIV infection.