The Impact of Adherence Counselling Incorporating a Point of Care Urine Tenofovir Assay on Virologic Suppression among Individuals Failing Tenofovir-Lamivudine-Dolutegravir: A Pre - Post intervention Study

Objectives: To examine if point-of-care urine tenofovir testing-informed counseling could be used to improve virologic suppression (VS) among participants with virologic failure (VF) after ≥1 prior round of enhanced adherence counseling (EAC).

Methods: Participants were enrolled from 42 clinics across Namibia. At each monthly medication pick-up, participants completed the point-of-care urine test and received EAC informed by this testing (EAC+). If VS was not achieved after 3 months of EAC+, up to 3 additional rounds of EAC+ were provided, with resistance testing at month (M)9.

Results: Of 310 potentially-eligible participants across 42 clinics in Namibia, we enrolled 211 participants with VF (median age 33 years, 61% female); 195 reached M3 defined as receiving EAC+ and follow-up viral load testing; 169 achieved VS within M3 (87%, p<0^.001) and 97% by M9 (181/186) compared to 40% (22/55) prior to the intervention (p<0.001). Resistance testing was performed in five remaining participants with VF at M9, of whom 1/5 (20%) developed dolutegravir resistance.

Conclusions: The urine tenofovir assay when incorporated into adherence counseling has potential to be a cost-effective intervention among participants failing tenofovir-based regimens, increasing VS to 97% in those failing TLD. Encouraging results of this pre-post intervention will be rigorously tested in a randomized trial.