Background:
In South Africa, young women carry a disproportionately higher HIV risk. Long-acting HIV pre-exposure prophylaxis (PrEP) methods may better align with women’s preferences, behaviors, and lifestyles-potentially improving PrEP uptake, adherence, and persistence. We studied the acceptance of implants for PrEP in women participating in a tenofovir alafenamide (TAF) implant trial.
Methods:
CAPRISA 018, a Phase I trial, assessed the safety and efficacy of sub-dermal TAF implants for PrEP. After receiving 1 or 2 TAF (110 mg) or placebo implants (4:1 randomization), participants (N=30) completed longitudinal (0-52 weeks) acceptability assessments on product attributes (implant size, quantity, insertion site, palpability, visibility), physical experiences (insertion procedures, pain, reactions/side effects, scarring), removal procedures, and method likes and dislikes. We averaged scores (range: 1-6, increasing with acceptability), reported minimum temporal means [min-max values] to assess acceptability (scores >4), and performed sub-group analyses by removal timing (scheduled [Week 48] vs. early). For early removals, acceptability was assessed 4 weeks post removal.
Results:
Participants were young (median age: 26 years) Black African women. Overall pre-removal product attributes (5.4 [3.6-6.0]) and physical experiences (4.9 [1.7-6.0]) remained acceptable over time (Figure 1). On average, women with scheduled removals had high levels of acceptability for product attributes and physical experiences during the study and 4 weeks after implant removal. Early removals occurred on average 4 months (0-8 months) after implant insertion among 11 (37%) of women. Women with early removals, on average, reported acceptable pre-removal and post-removal product attributes and physical experiences; however, all reported unacceptable levels of side effects at least once during the study (100% in early removals versus 47% in scheduled removals, p=0.004). Both groups reported that implants were acceptable as a potential long-term PrEP method (5.3 [3.0-6.0]), and the most-cited reason for liking the implants was possibility of long-term HIV protection.
Conclusions:
Although women in the trial reported high levels of acceptability for implant attributes, physical experiences, and insertion and removal procedures overall, higher than expected early discontinuation rates due to side effects were observed. The implants potential for long-term HIV protection was its most favored attribute for acceptability.
