Post-market surveillance of antiretroviral drug quality in Tanzania in the context of rising HIV drug resistance

Human Immunodeficiency Virus (HIV) remains a major global health burden. Antiretroviral (ARV) drugs play a key role in the control of HIV. However, their effectiveness could be affected by poor-quality drugs, risking treatment failure and HIV drug resistance (HIVDR). Reports on the quality of ARV drugs from sub-Saharan Africa remain low despite the growing threat of HIVDR. This study presents Tanzanian post-market surveillance (PMS) data on ARV quality, offering evidence to strengthen monitoring systems and inform HIV/AIDS control strategies. This was a descriptive cross-sectional study conducted across 15 regions of mainland Tanzania. ARVs were randomly sampled from the port of entry and distribution outlets. All samples underwent Tier I screening, which included visual inspection, disintegration tests, and Thin Layer Chromatography using a Global Pharma Health Fund Minilab. Samples from the distribution outlet were also subjected to product information review (PIR). All samples that failed Tier I screening, irrespective of their source, were subjected to Tier II confirmatory testing using standard methods. In addition, 10% of samples from distribution outlets that passed Tier I screening were randomly selected for Tier II confirmatory testing in accordance with the national PMS guideline. Samples were considered to pass if the test results complied with the standard pharmacopeia acceptance criteria. A total of 1432 ARV samples were collected from July 2019 to December 2023. Of these, 81.8% (1171/1432) were collected from the port of entry. The first line combination (dolutegravir + lamivudine + tenofovir disoproxil fumarate) comprised about two-thirds (68%) of the screened samples. Nearly half (49.4%) of ARVs from the distribution outlets did not comply with the PIR requirements of the approved product information. Failure to comply with the PIR requirement risks the public health, safety and effective use of ARVs. All samples passed Tier I and Tier II tests. This study demonstrates that ARVs circulating in Tanzania meet the required quality standards; however, the observed labeling deviations necessitate urgent corrective action. In light of rising HIVDR, continuous quality surveillance remains essential.