Pharmaceutical quality of artemether-lumefantrine in Rwanda’s public health supply chain: a cross-sectional post-market surveillance study

Substandard and falsified (S&F) antimalarial medicines undermine malaria control efforts across sub-Saharan Africa, with an estimated 19% of antimalarials failing to meet quality standards and contributing to 40,000–160,000 preventable deaths annually. ACTs, particularly artemether-lumefantrine (AL), are the cornerstone of malaria treatment, yet their effectiveness is threatened by poor pharmaceutical quality and emerging drug resistance. This study evaluated the pharmaceutical quality of AL circulating in Rwanda's public health supply chain to assess compliance with international pharmacopeial standards. A cross-sectional survey was conducted in February 2023 across eight districts representing all five provinces of Rwanda and encompassing both high- and low-malaria transmission settings. A total of 19 samples (3588 AL tablets) were sampled from three supply chain levels: Rwanda Medical Supply (RMS) headquarters and district branches, health centers, and Community Health Workers. Samples underwent comprehensive quality testing at a WHO-recognized laboratory, including visual inspection, tablet weight determination, high-performance liquid chromatography (HPLC) assay for artemether and lumefantrine content (acceptance range: 95.0–105.0%), and dissolution testing using pharmacopeial methods. The study followed Medicine Quality Assessment Reporting Guidelines (MEDQUARG) guidelines for medicine quality surveillance. All 19 samples (3588 tablets, 100%) met international pharmacopeial quality standards across all testing parameters. Visual inspection revealed no packaging defects, labeling errors, or tablet abnormalities. Tablet weight uniformity complied with specifications for both dispersible tablets (mean: 356.27 mg; range: 355.04–357.65 mg; specification: 339.50–360.50 mg) and regular tablets (mean: 241.63 mg; range: 239.79–242.72 mg). Artemether assay values ranged from 97.3 to 99.4% (mean: 98.7%), while lumefantrine ranged from 97.3 to 104.3% (mean: 99.2%), with all samples meeting the 95.0–105.0% acceptance criteria. Dissolution testing demonstrated 100% compliance for both active pharmaceutical ingredients across all samples. All AL samples met international quality standards, contrasting with sub-Saharan Africa's 19% failure rate. Rwanda's centralized procurement, regulatory oversight, and WHO-prequalified sourcing demonstrate a replicable model for ensuring antimalarial quality and combating drug resistance.