Efavirenz: new preparation. An alternative to HIV protease inhibitors

(1) Efavirenz, a non nucleoside HIV reverse transcriptase inhibitor, is indicated, in combination with other antiretroviral drugs, for the treatment of HIV infection. (2) The methodologically sound clinical file is limited to trials based on validated surrogate end points (viral load) and involving patients in the early stages of HIV infection. (3) Two dose-finding studies favour a dose regimen of 600 mg in a single daily intake for adults. (4) Interim results of three ongoing trials are also available. After 48 weeks of treatment, three-drug regimens comprising efavirenz plus two nucleoside inhibitors were more effective on viral load than three-drug regimens comprising indinavir plus two nucleoside inhibitors. In another trial, after 24 weeks of treatment, a three-drug regimen combining efavirenz and two nucleoside inhibitors was no more effective on viral load than a three-drug regimen comprising nelfinavir and two nucleoside inhibitors. (5) It remains to be determined if four-drug regimens comprising efavirenz, a protease inhibitor and two nucleoside inhibitors are superior to three-drug regimens. (6) Data on the safety profile of efavirenz show mainly neuropsychological and cutaneous disorders. The severity of cutaneous effects in children needs further assessment.