Combination chemotherapy for human immunodeficiency virus-1

Combination therapy approaches are becoming the mainstay of treatment for a variety of neoplastic and infectious diseases, including human immunodeficiency virus (HIV)-1 infections. The advantages of combination therapy include potentially additive-to-synergistic antiviral interactions, decreased emergence of or wider coverage against resistant viruses, and broadened effect both in terms of cell types and tissue reservoirs. However, combination drug interactions may range from synergy to antagonism. Both in vitro and in vivo studies have identified agents demonstrating additive-to-synergistic effects when used together and support the use of combination strategies in clinical practice. These will be reviewed in the context of their use in the setting of healthcare worker postexposure prophylaxis.