Potential risk of drug–drug interactions with hormonal contraceptives and antiretrovirals: prevalence in women living with HIV
Background: Family planning services are vital for women living with HIV (WLH); however, the use of concomitant antiretroviral therapy (ART) and hormonal contraceptives (HCs) may pose challenges due to the risk of potential drug–drug interactions (DDIs). The objectives of this study were to assess ART and HC use among WLH and quantify the frequency of potential DDIs between ART and HCs.
Methods: This was a retrospective, observational, cohort study of WLH aged 18–55 years, prescribed ART, with at least one clinic visit from January 1, 2010 to April 30, 2014. Potential DDIs between HCs and ART were assessed using the University of Liverpool HIV Drug Interactions website (www.hiv-druginteractions.org) and categorized as ‘weak potential interaction,’ ‘potential interaction,’ or ‘do not co-administer.’
Results: Overall, a contraceptive method was reported in 167 (54%) of the 309 women included in the study. Of those using contraception, 73 (43.7%) reported using HCs, which was most frequently a progestin intrauterine device (n=43), progestin injection (n=17), or combination oral contraceptive pills (n=9). Out of a total of 449 ART regimens, a potential DDI was identified in 21 of 115 (18.3%) ART–HC combinations from 19 women using ART and HCs. Atazanavir/ritonavir was the most common potentially interacting ART (10, 47.6%); for HCs, these were combination oral contraceptive pills (16, 76.2%) and progestin implants (2, 9.5%).
Conclusion: In this cohort, one-quarter of WLH on ART–HCs had a potential DDI. Future studies should investigate the impact of DDIs on unintended pregnancies, the side effects of DDIs, and the effects of HC DDIs on ART concentrations.