HIGH-DOSE NEVIRAPINE IN PREVIOUSLY UNTREATED HUMAN-IMMUNODEFICIENCY-VIRUS TYPE 1-INFECTED PERSONS DOES NOT RESULT IN SUSTAINED SUPPRESSION OF VIRAL REPLICATION

High-dose nevirapine treatment has been reported to confer sustained a ntiretroviral effects, despite a rapid development of resistance. The use of this strategy was evaluated in 20 previously untreated human im munodeficiency virus type 1 (HIV-1) p24 antigenemic persons with CD4 c ell counts between 100 and 500/mm(3). Treatment consisted of 400 mg of nevirapine, after a 2-week lead-in dose of 200 mg. Rash was the most frequently reported adverse event, occurring in 25%, While sustained d eclines in p24 antigen levels were observed in the majority, serum HIV -1 RNA load and CD4 cell counts returned to baseline values within 12 weeks in virtually all subjects. The resistance-conferring tyrosine-to -cysteine substitution at reverse transcriptase position 181 was detec ted after 4 weeks in most subjects. These observations suggest that pl asma drug levels attained with high-dose nevirapine were not sufficien t to inhibit nevirapine-resistant virus, although they were similar to 2-fold higher than reported IC50 values of resistant virus.