Short-term adverse effects from and discontinuation of antiretroviral post-exposure prophylaxis

Objective: To evaluate short-term toxicity from and discontinuation of anti retroviral combination prophylaxis in HIV-exposed individuals in Italy. Design: Longitudinal, open study conducted by prospective collection of dat a in the National Registry of PEP. Setting: All the Italian centres dedicat ed to HIV related care and licensed by the Ministry of Health to dispense a ntiretroviral drugs. Study population: Health care workers and other persons consenting to be tr eated with post exposure prophylaxis (PEP) after exposures to HIV. Results: Until October, 2000, 207 individuals receiving two nucleoside reve rse transcriptase inhibitors (NRTIs), and 354 receiving two NRTIs plus a pr otease inhibitor (Pl) were enrolled. More individuals experienced side-effects in the 3-drug group (53% and 62%, respectively; OR 0.68, (95% Cl 0.48-0.98), p < 0.03). However, the proport ion of individuals discontinuing prophylaxis because of side-effects did no t differ significantly between the 2 groups (21% and 25% respectively; OR 0 .82 (95% Cl 0.53-1.26); p = 0.4). The 43 individuals in the 2 NRTI group di scontinued PEP after a mean of 10.4 days of treatment (median 8, range 1-27 ), similarly to the 88 discontinuations observed in the 3-drug group (mean duration 10.5 days, median 7.5, range 1-26). Type and incidence of specific adverse effects were similar to those reported in the literature. Conclusion: Our study indicates that the difference in the proportion of in dividuals developing side effects and discontinuing PEP is not significant. The rate of discontinuation because of protease inhibitor side-effects doe s not justify per se the initial use of a less potent PEP regimen. We sugge st initiating PEP with a three-drug regimen and discontinuing the protease inhibitor in the case of adverse effects.