Oral preexposure prophylaxis uptake, adherence, and persistence during periconception periods among women in South Africa

Abstract

Objective: We developed the Healthy Families-PrEP intervention to support HIV-prevention during periconception and pregnancy. We evaluated preexposure prophylaxis (PrEP) use with three objective measures.

Design: This single-arm intervention study enrolled women in KwaZulu-Natal, South Africa, who were HIV-uninfected, not pregnant, in a relationship with a partner with HIV or unknown-serostatus, and with pregnancy plans. PrEP was offered as part of a comprehensive HIV prevention intervention. Participants were followed for 12 months.

Methods: We evaluated periconception PrEP uptake and adherence using quarterly plasma tenofovir concentrations. We modeled factors associated with PrEP uptake and high plasma tenofovir (past day dosing). Patterns of use were analyzed using electronic pillcap data. Dried blood spots to measure intracellular tenofovir product (past 2 months dosing) were analyzed for a subset of women.

Results: Three hundred thirty women with median age 24 (IQR: 22-27) years enrolled. Partner HIV-serostatus was unknown by 96% ( N = 316); 60% (195) initiated PrEP. High plasma tenofovir concentrations were seen in 35, 25, 22, and 20% of samples at 3, 6, 9, and 12 months, respectively. Similar adherence was measured by pillcap and dried blood spots. In adjusted models, lower income, alcohol use, and higher HIV stigma were associated with high plasma tenofovir. Eleven HIV-seroconversions were observed (incidence rate: 4.04/100 person-years [95% confidence interval: 2.24-7.30]). None had detectable plasma tenofovir.

Conclusion: The Healthy Families-PrEP intervention supported women in PrEP use. We observed high interest in periconception PrEP and over one-third adhered to PrEP in the first quarter; one-fifth were adherent over a year. High HIV incidence highlights the importance of strategies to reduce HIV incidence among periconception women.

Clinical trial number: NCT03194308.

Fig. 1

Consort diagram.

Fig. 2

Periconception PrEP use over 12 months by electronic pillcap (proportion of days pillcap opened summarized over prior quarter), plasma TFV (past day use), intraerythrocytic TFV-DP (past 8 weeks use).

Fig. 3

Proportion of N = 180 periconception participants who started PrEP and used the electronic pillcap who had adherence gaps of 1 through ≥14 days.

Fig. 4

Time to PrEP discontinuation (black) and 95% CI (grey), where PrEP discontinuation is defined as the first 14-day interruption in treatment without resumption (based on pillcap data) among N = 180 periconception participants who initiated PrEP.