A dual nucleoside analogue combination that contains abacavir is more potent than a non-abacavir-containing combination in children, according to the findings of the PENTA 5 study published last week in The Lancet.
PENTA 5, a study sponsored by the Paediatric European Network for Treatment of AIDS, randomised 130 children from 34 centres in Europe to receive either AZT/3TC/ AZT/abacavir or 3TC/abacavir. Children with more advanced HIV disease also received nelfinavir (n= 73).
Children who received abacavir had significantly lower levels of viral load after 48 weeks of follow-up (-1.71 log in the AZT/3TC group, -2.19 log in the AZT/ABC group and -2.63 log in the 3TC/ABC group). The difference was already apparent at week 24 and there was no difference in the discontinuation rate of any drugs, suggesting that the difference can be explained by the potency of abacavir-containing combinations.
Only four potential hypersensivity reactions were observed in this study (a rate of 3%), of which two were subsequently identified as acute infections. Twenty four serious adverse events were reported, of which the most common were neutropenia (12) and thrombocytopenia (3). These were evenly distributed between the treatment groups. Although diarrhoea was more frequent in the nelfinavir group, no child stopped treatment because of it.
The combination of abacavir and 3TC was considered particularly attractive by the researchers because both drugs can be given as tolerable-tasting liquids twice a day in small volumes, essential features of any medication intended to be given to children indefinitely. The authors suggest that “good adherence could have contributed to the effectiveness of this combination in PENTA 5”.
Paediatric European Network for Treatment of AIDS (PENTA). Comparison of dual nucleoside analogue reverse-transcriptase inhibitor regimens with and without nelfinavir in children with HIV-1 who have not previously been treated: the PENTA 5 randomised trial. The Lancet 359: 733-740, 2002.