US confirms HIV generic drug dosage claims

The first published analysis of the nevirapine content of several generic formulations of antiviral drugs has found them to be in line with the manufacturers' claims.

Products from the two Indian companies Cipla and Aurobindo Pharma were obtained in Zambia and Kenya and analysed alongside samples of nevirapine from Boehringer Ingelheim obtained in Lithuania and South Africa. The tests covered single-drug formulations of nevirapine from all three manufacturers and one fixed-dose combination, Cipla's Triomune, which combines nevirapine, d4T and 3TC.

Six tablets representing each of six batches of products were compared using high-performance liquid chromatography with pure nevirapine supplied by Boehringer Ingelheim. Apart from the pure nevirapine, all other samples were obtained from local pharmacists and supplied to NIH by physicians attending a training programme in the USA in April 2002.

In all cases, the claimed dosage of nevirapine was 200mg per tablet. The actual dosages were found to average 197.9mg, which is almost 99.0% of that claimed. Variation in dosage was small and unlikely to be a problem between batches, given the manufacturing standards known to be followed by the companies concerned. However, as the authors state, additional studies are needed to extend these findings to other manufacturers and to show 'bio-equivalence' (in other words, that the medicines are absorbed in the same way and have the same effects in the body).

Short as it is, this report from the US National Institutes of Health complements WHO's collection of data on manufacturing procedures to 'pre-qualify' drugs for licensing and purchase using the Global Fund to fight AIDS, TB and Malaria. This report may also help explain US President George W Bush's implicit reliance, in his State of the Union initiative, on generic drugs to underpin large-scale US-funded HIV treatment access in Africa and the Caribbean.

Further information on this website

Fixed-dose combination drugs based on nevirapine have been discussed in NAM's newsletter, 'HIV & AIDS Treatment in Practice' and the article can be read here.