Abstract
BACKGROUND: PrEP use should be aligned with periods of risk for HIV acquisition. For HIV serodiscordant couples, PrEP can be used as a bridge until the partner living with HIV takes antiretroviral therapy (ART) long enough to achieve viral suppression (the "PrEP as a Bridge to ART" strategy). However, adherence to this strategy is unknown. METHODS: In a demonstration project in Kenya and Uganda, HIV-uninfected partners of serodiscordant couples were advised to take PrEP until the partner living with HIV took ART for ≥ 6 months. PrEP discontinuation was then recommended unless there were concerns about ART adherence, immediate fertility intentions, or outside partners with unknown HIV/ART status. Electronic adherence monitoring and socio-behavioral questionnaire data were used in logistic regression models to explore completion of this strategy and continuation of PrEP beyond recommendations to stop its use. RESULTS: Among 833 serodiscordant couples, 436 (52%) HIV-uninfected partners completed ≥ 6 months of PrEP as a bridge to ART. Strategy completion was associated with older age (aOR per 5 years = 1.1; p = 0.008) and having fewer children (aOR = 0.9; p = 0.019). Of the 230 participants encouraged to stop PrEP according to strategy recommendations, 170 (74%) did so. PrEP continuation among the remaining 60 participants was associated with more education (aOR = 1.1; p = 0.029), a preference for PrEP over ART (aOR = 3.6; p = 0.026), comfort with managing their serodiscordant relationship (aOR = 0.6; p = 0.046), and believing PrEP makes sex safe (aOR = 0.5; p = 0.026). CONCLUSION: Half of participants completed the PrEP as a bridge to ART strategy and the majority stopped PrEP as recommended. These findings suggest that targeting PrEP to periods of risk is a promising approach; however, tailoring counseling around aligning PrEP use and HIV risk will be important for optimal strategy implementation.