Oligonucleotide Ligation Assay (OLA)-Simple: Field Implementation, Usability, and Performance of a near Point-of-Care HIV Drug Resistance Assay in Kenya

A point-of-care (POC) HIV drug resistance (HIV-DR) test is needed for low- and middle-income countries (LMICs). Oligonucleotide Ligation Assay (OLA)-Simple, designed as a near-POC HIV-DR test, was assessed for its overall usability in Kenya by technicians with and without molecular laboratory PCR experience. Further, its diagnostic accuracy was evaluated by PCR-experienced technicians utilizing 147 plasma samples with known Sanger sequence genotypes-based on seven major HIV-DR mutations of nucleotide and non-nucleoside reverse transcriptase inhibitors. Thirteen laboratory technicians were recruited, including five with prior PCR experience. Twelve technicians completed the training and attained OLA-Simple testing competency, ten of whom were able to perform the OLA-Simple test within 6 h. Technicians' survey feedback indicated the user-friendliness of OLA-Simple, citing straightforward reagent reconstitution, concise instructions in prompts, and a shorter sample-to-result test time compared to standard genotyping assays. Of the 147 archived plasma samples tested, 132 (90%) yielded interpretable results. OLA-Simple assay demonstrated a sensitivity of 97.3% (95% CI 94.5, 98.9), a specificity of 97.2% (95% CI 95.5, 98.3), and a percent agreement of 97.1% (95% CI 95.9, 98.2) compared to Sanger sequencing. This evaluation found that OLA-Simple was user-friendly among intended end-users and performed well. LMIC HIV programs would benefit from strategizing on case-use scenarios for such near-POC HIV-DR assays to improve HIV outcomes.