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Background:  Generic and discounted brand name antiretroviral (ARV) medications are becoming increasingly available in developing countries. To date, little information is available on drug content versus label claims for these medications. The purpose of this study was to assess drug content compared to the labeled amount among ARV obtained from developing countries.

Methods:  We analyzed 6 ARV medications from 6 manufacturers and 4 international sources (Lithuania, South Africa, Jamaica, and Zambia). In total, 12 different lots of medication were obtained in hospital or commercial clinic pharmacies and brought to the United States unrefrigerated. Drugs were then assessed for active ingredient. Drug manufacturers included BMS (efavirenz, 1 lot), Merck (efavirenz, 1 lot; indinavir, 3 lots), Aurobindo Pharma Ltd. (indinavir, 1 lot), Abbott (lopinavir/ritonavir, 1 lot; ritonavir, 2 lots), GSK (amprenavir, 1 lot), and Roche (saquinavir soft gel caps, 2 lots). Drug content was determined with HPLC; a modified United States Pharmacopeia (USP) Uniformity of Dosage Units test was applied; this test specifies that the drug content of an individual capsule be within 85 to 115% of the label claim. For all analyses, 2 to 4 capsules were assayed 6 to 9 times per dosage unit. Drug content (percent of label claim) and coefficient of variation are reported.

Results:  With the exception of ritonavir, which was not stored under continual refrigeration, the active ingredient in each of the drug products was within USP specifications; drug content was between 88 and 115% of labeled amounts. The absolute value of the mean difference between measured and labeled drug content was 7.7% and the median difference was -2.0%. Amprenavir, from a single international source, was tested after its expiration date and contained 92% of its labeled amount. Ritonavir content, by itself and combined with lopinavir, was between 81 and 84% of the labeled amount in tested preparations. The coefficient of variation among capsules in individual lots was less than 10.2% for ritonavir and less than 8.9% for all other tested medications.

Conclusions:  These quality-control data among generic and branded ARV are encouraging; they also highlight the importance of storing ritonavir-containing products under continual refrigeration in accordance with manufacturer specifications. Continued quality-control, as well as bioequivalence studies are necessary to identify inferior and/or counterfeit ARV in developing countries.

Keywords: Developing Countries; Generic; Quality-control