9th Conference on Retroviruses and Opportunistic Infections Seattle, Washington - February 24 -February 28, 2002

Conf Retroviruses Opportunistic Infect 2002 Feb 24-28;9:abstract no. 15
M. Schechter*¹ , R. F. Lago¹ , R. Ismerio¹ , A. B. Mendelsohn², and L. H. Harrison^2
1Univ. Federal do Rio de Janeiro, Brazil and ²Univ. of Pittsburgh, PA

BACKGROUND: There are limited data on the acceptability, behavioral impact, and efficacy of the availability of PEP to prevent sexual acquisition of HIV infection. PEP could increase the risk of HIV infection if its availability resulted in increased high-risk behavior.

METHODS: HIV seronegative homosexual males were included in this study. Participants were given a 4-day supply of ZDV+3TC and instructed to begin PEP immediately after sexual exposure of a mucous membrane to blood or semen, and to report for evaluation within 4 days. For exposures deemed to fulfill study criteria, a further 24-day supply was given.

RESULTS: 202 subjects were enrolled and followed for a median of 24.2 months, for a total of 4600 person-months of follow-up. At enrollment, the median age was 28 years, and the mean number of male partners in the previous 6 months was 6.2. The percentage of participants reporting any high-risk exposure; on anal, oral, or vaginal high-risk exposures at baseline and at 24 months were 56.6 and 39.7 (McNemar's test, p=0.001), 39.4 and 28.0 (p=0.009), 24.1 and 11.5 (p=0.001), and 5.6 and 7.6 (p=0.16), respectively. PEP was initiated 110 times by 73 participants; 101 (91.8%) of exposures were considered eligible for PEP. The full course was completed 91.1% of the time. There were 11 HIV seroconversions, 10 among non-PEP users and 1 that occurred despite PEP. Virus obtained on day 28 of PEP use from the sole PEP failure showed a 3TC-resistance mutation (M184V). The seroincidence was 2.9, 4.1, and 0.7 per 100 person-years for the whole cohort, for those who never used PEP and for PEP users, respectively.

CONCLUSION: Although reported subjective side-effects were relatively common, > 90% of PEP courses were completed. The reported behaviors on average improved in this cohort with access to PEP. PEP failure occurred only once and it was associated with resistance to one of the antiretrovirals used.

020224
15

Copyright © 2002 - Foundation for Retrovirology and Human Health. Reproduction of this abstract (other than one copy for personal reference) must be cleared through the Foundation for Retrovirology and Human Health. Licensed (AIDSLINE) from National Library of Medicine.