Frequency of cutaneous reactions on rechallenge with nevirapine and delavirdine

OBJECTIVE: To determine the frequency of cutaneous reactions in a group of HIV-infected adults attending a public hospital HIV clinic who received nevirapine, delavirdine, or both, as well as the consequences of rechallenge with the same or alternative agent. DESIGN: The medical records of patients who had received either or both agents between March 1997 and July 1998 were reviewed, including 69 patients who initially received nevirapine and 20 who initially received delavirdine. Gender, ethnicity, HIV status, and plasma HIV RNA concentrations were analyzed as risk factors for the development of rash. RESULTS: The overall incidence of rash attributed to the initial use of one of these drugs was 37.1%. While rash due to delavirdine occurred more often, the rash due to nevirapine was more severe and resulted in hospitalization more frequently. There was a trend toward a higher frequency of rash in Latinos and possibly in women, but HIV status, CD4+ cell counts, and plasma HIV RNA were not risk factors for the development of rash. Drug therapy was temporarily or permanently discontinued because of rash in 19 of 69 (28%) and in five of 20 (25%) patients initially receiving nevirapine or delavirdine, respectively. Rash recurred in six of eight (75%) patients rechallenged with the same agent, and in seven of 10 (70%) who were crossed over to the alternative agent because of rash. Fever, in the absence of any apparent cause, was a significant predictor for the development of rash in patients receiving nevirapine. CONCLUSIONS: There is probably little value in attempting to retreat patients with cutaneous reactions, even with the alternative agent, except in patients with limited treatment options.