Trial results for pre-exposure prophylaxis (PrEP) adherence support strategies in young South African women at risk of HIV were posted on ClinicalTrials.gov on 2026-05-04. The study found that probabilities of high PrEP adherence at nine months ranged from 0.24 to 0.27 across different intervention arms.
Background
HIV/AIDS remains a significant global health challenge, particularly in regions like South Africa where young women face a disproportionately high risk of infection. Pre-exposure prophylaxis (PrEP) is a highly effective prevention method, but its efficacy relies heavily on consistent adherence. Supporting individuals in maintaining high adherence to PrEP is crucial for maximizing its public health impact. This study explored scalable adherence support strategies to address this critical need.
Trial design
This completed trial, known as "The PrEP (Pre-exposure Prophylaxis) SMART Study," enrolled 360 participants, focusing on young women in South Africa initiating PrEP. The study utilized a sequential multiple assignment randomized trial (SMART) design to test various stepped models of adherence support. The conditions studied related to HIV/AIDS, specifically focusing on PrEP adherence. Interventions included 2-Way SMS and WhatsApp Groups, with additional monthly counseling or drug-level feedback counseling for non-responders.
Key results
The study reported on PrEP adherence, discontinuation, and the probability of high PrEP adherence at nine months across different intervention strategies.
- For PrEP Adherence, 34 participants were reported in the 2-Way SMS group and 32 participants in the WhatsApp Groups.
- For PrEP Discontinuation, 19 participants were reported in the 2-Way SMS group and 18 participants in the WhatsApp Groups.
- The probability of high PrEP adherence at nine months was assessed for various stepped strategies:
- For SMS, with the addition of monthly counseling for non-responders, the probability was 0.25 (95% Confidence Interval).
- For SMS, with the addition of drug-level feedback counseling for non-responders, the probability was 0.27 (95% Confidence Interval).
- For WhatsApp, with the addition of monthly counseling for non-responders, the probability was 0.24 (95% Confidence Interval).
- For WhatsApp, with the addition of drug-level feedback counseling for non-responders, the probability was 0.24 (95% Confidence Interval).
What this means
The results indicate that various scalable adherence support strategies, including SMS and WhatsApp-based interventions, yielded similar probabilities of high PrEP adherence over nine months, ranging narrowly from 0.24 to 0.27. While all strategies showed some level of adherence, the highest probability was observed with SMS combined with drug-level feedback counseling for non-responders. The relatively low numbers for PrEP discontinuation in both the 2-Way SMS (19 participants) and WhatsApp Groups (18 participants) suggest that these digital support methods may contribute to sustained engagement with PrEP. These findings offer insights into potential strategies for improving PrEP adherence in similar high-risk populations.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT04038060, titled "The PrEP (Pre-exposure Prophylaxis) SMART Study," were posted on 2026-05-04 on clinicaltrials.gov.