Clinical Trial on the Effects of Progestin-based Contraception in the Genital Tract of HIV-infected and Uninfected Women

Hormonal contraception is a central component in the prevention of unintended pregnancy; however there are concerns that certain methods may increase the risk of heterosexual HIV acquisition and transmission. Some studies, but not others, have suggested a link between hormonal contraceptive use and enhanced HIV-susceptibility, more rapid HIV disease progression, and increased transmissibility to partners. Hormonal contraception modifies the genital mucosa in several ways, and the interactions of the endocrine and immune system are complex but incompletely understood. In some cross-sectional studies, hormonal contraceptives appear to be associated with increased shedding of HIV DNA, but not RNA, in the genital tract, and the significance of these findings for HIV transmissibility are unclear. Very few studies have examined genital HIV shedding prospectively before and after initiation of contraception. The effects of hormonal contraception in the setting of antiretroviral therapy (ART) are also unknown.

Hormonal contraception, particularly injectable DMPA, is widely used in many parts of the world, including settings with high HIV prevalence. It is important that the effects of hormonal contraception on HIV acquisition and HIV shedding and subsequent transmissibility be determined. The effect of progestin contraceptive implants, such as the levonorgestrel rod implant (LNG implant), on HIV shedding is unknown, and it will be of interest to evaluate it compared with the injectable progestin (DMPA), given their different kinetics of hormone release, differences in progestin type, and the high efficacy of both methods.

We propose a pilot study among 100 HIV-infected women and 30 uninfected women in Lilongwe, Malawi randomized to either DMPA or LNG implant to: 1) assess the effect and compare the impact of type of progestin-containing contraception (injectable versus implant) on HIV viral shedding in the genital tract of HIV+ women, 2) assess the effect and compare the impact of type of progestin-containing contraception (injectable versus implant) on inflammatory/immune markers in the genital tract of both HIV+ and HIV- women, and 3) assess the interaction of progestin-based hormonal contraception and ART by examining: i. contraceptive efficacy (measured by systemic hormone levels and pregnancy rate during follow-up), and ii. ART efficacy (by drug concentrations in blood and genital tract and HIV viral load response in the plasma in women on ART).

An overall study aim is to determine the feasibility and need for a larger study of determinants of HIV transmissibility and acquisition in this population.

The study would take place at Bwaila Maternity Hospital, which was the site of the CDC-sponsored Breastfeeding, Antiretrovirals, and Nutrition (BAN) clinical trial, a partner project with this study. Women attending the clinics at Bwaila (a large proportion of whom participated in the BAN study) who desire to start hormonal contraception will be informed of the new study and counseled on the progestin-based contraceptives that are available within the study. BAN women will be specifically targeted for recruitment through radio messages. Eligible women who provide informed consent and agree to randomization to either DMPA or the LNG implant will be enrolled. HIV-infected women may be on ART or they may be pre-ART.

To address the primary outcomes of HIV shedding and mucosal immune activation, we will quantify genital tract HIV RNA and inflammatory/immune markers at two time points before and four time points after randomization of the 100 HIV-infected and 30 HIV-uninfected women to DMPA or LNG-implant. The two time points prior to randomization will occur within the prior menstrual cycle, so that one visit occurs in the follicular phase and the other occurs in the luteal phase of the cycle. Assessments after initiation of contraception will occur on days 3, 30, 90, and 6 months. Antiretroviral levels in the blood and genital tract will also be assessed at these time points.

Based on recent evidence suggesting that the LNG implant may have decreased contraceptive efficacy when used in combination with the antiretroviral efavirenz, study follow-up will be extended to include visits at about 9, 12, 15, 18, 21, 24, 27, 30, and 33 months after initiation of contraception for a total of 6 additional visits per participant. Not all participants will start the study extension at the same time point, so the 6 additional visits can span from about 9 months to 24 months after contraceptive initiation to about 18 months to 33 months after contraceptive initiation. Assessments at these visits will address the outcomes of contraceptive and ART efficacy and HIV shedding.

To analyze the effects of progestin contraception on HIV shedding, as well as the effect of each contraceptive type, HIV-infected women on progestin-based contraception will be compared within each study arm (before and after initiation of contraception), as well as between the two contraceptive arms. Antiretroviral use will be evaluated for an independent effect on HIV shedding and also to determine if it modifies the effect of menstrual cycle or progestin contraception on HIV shedding. To analyze the effects of progestin contraception on genital inflammatory/immune markers, both HIV-infected and HIV-uninfected women on progestin-based contraception will be compared separately and combined, with HIV status treated as a potential effect modifier, within each study arm (before and after initiation of contraception), as well as between the two contraceptive arms. This study will provide information on acceptability of randomization to contraceptive options, overall study retention, and estimates of the effect of progestin contraception on HIV genital shedding and inflammatory/immune perturbations in women who may or may not be on antiretroviral therapy, as well as in HIV-uninfected women controls. This information will be instrumental in determining the need for and feasibility of a larger study to address these outcomes.