Safety, tolerability and effectiveness of HIV non-occupational prophylaxis in Taiwan

Increasing numbers of new HIV infection is an important issue of public health in Taiwan. We aim to evaluate the safety, tolerability and effectiveness of HIV non-occupational prophylaxis (nPEP) in Taiwan.

We conducted a prospective cohort observational study between March 2011 and May 2014. Three-combined antiretroviral agents were prescribed for all the persons who sought for HIV post-exposure prophylaxis after high risk sexual behaviour. HIV screening, health education and consultation were done before initiation of nPEP. Adverse effects were evaluated at Weeks 1, 2 and 4 and effectiveness was evaluated at Weeks 12 and 24. We also assessed adherence by pill count and regimen completion rates.

During the study periods, 255 persons were enrolled. Among the enrolled cases, 43.9% (112/255) of them received zidovudine (AZT)-based regimen while the others received tenofovir (TDF)-based regimen and the third agent was composed of mostly lopinavir/ritonavir (81.4%). The completion rate of nPEP was 85.9% (219/255), and discontinuation rate of nPEP among AZT-based regimen is higher than TDF-based regimen (17.0% vs 8.2%). Any grade adverse effects are higher among AZT-based regimen than TDF-based regimen (62.5% vs 32.1%) although most adverse effects were grade 1-2. After a 24-week follow-up, only one person experienced HIV seroconversion and he had primary syphilis at the moment when he sought for nPEP.

NPEP could be an effective prevention method in a part of HIV prevention strategy and TDF-based regimen had better tolerability in Taiwan.