Delayed antiretroviral refills as an early clinical alert: a pharmacist-led strategy to improve viral suppression in Malaysia.

Monitoring adherence to antiretroviral therapy (ART) often relies on viral load testing or patient self-report, which may identify problems only after adherence has declined. This study explored whether delays in ART refill, a readily observable and operationally simple metric, could be transformed into a real-time clinical alert prompting immediate pharmacist-led intervention. At Hospital Sungai Buloh, Malaysia, adults on ART who collected medication ≥3 days late between January and December 2022 were identified. A total of 101 patients received structured adherence counselling from trained HIV pharmacists and were compared with patients with consistently timely refills. The primary outcome was change in medication possession ratio (MPR) over six months; secondary outcomes included viral suppression and patient-reported barriers to timely refill. Overall, 85% of refills were on time (n = 691), below the WHO benchmark. Among late-refill patients, mean MPR improved from 80.77% to 95.20% after counselling, while detectable viral load decreased from 23.8% (24/101) to 3.0% (3/101). Baseline MPR <90%, previous non-adherence, and greater distance from the hospital were associated with refill delay. These findings demonstrate that delayed refill, when systematically acted upon, serves as a pragmatic, low-cost early-warning signal that may help identify patients at risk of virological failure and support long-term ART success.