SAINT Trial: Mbeki offered more proof on nevirapine's use in pregnancy

According to new data presented at the 13th International AIDS Conference in Durban yesterday, a simple antiretroviral intervention consisting of three doses of nevirapine is as effective in reducing the rate of perinatal mother to child transmission of HIV as a seven day course of dual therapy.

The South African SAINT study enrolled over 1,300 HIV-positive pregnant women. Participants were randomised to a nevirapine arm, where treatment consisted of a single dose of the NNRTI given at the onset of labour, a second dose 24 to 48 hours after delivery, plus a single dose to the newborn; or to receive a short course of dual nucleoside analogue therapy. The regimen in the dual therapy arm involved a standard dose of AZT and 3TC given at the onset of labour, and then three hourly doses until delivery. Treatment then continued for the next seven days for both mother and baby.

Results are available for just over 650 deliveries in each arm. Treatment was administered less than two hours before birth in a quarter of cases in both groups. Following birth, mothers were counselled on the risks and benefits of breastfeeding and given the choice over whether to bottle or breastfeed their child. In each arm, 40% of women elected to breastfeed.

Eight weeks after birth, there was no difference observed between the rate of HIV infection or death across the two treatment arms, with a rate of 12.5% in the dual therapy arm and 14.3% in the nevirapine arm.

Presenting author Daya Moodley, stressed that these results reflect the impact of treatment on perinatal transmission only, however, and that further measures are required to limit the ongoing risk of transmission associated with breastfeeding. Of a range of factors analysed, maternal viral load and breastfeeing were significantly associated with transmission.

In a separate presentation, James McIntyre of the Chris Hani Baragwanath Hospital, Soweto, discussed safety data from the SAINT study. Both regimens were generally well-tolerated by both mothers and children, and there was no difference in infant mortality between arms. There was no evidence that the use of nevirapine was associated with liver toxicity, a concern levelled at manufacturers Boehringer Ingelheim by the South African government following an earlier trial. Information on the emergence of drug resistance in SAINT, a problem which arose in a Ugandan pilot study of this regimen, is not yet available however. According to newspaper reports, this issue remains a concern for ministers here in South Africa, where the Medicines Control Council are currently considering an application for nevirapine’s approval for use in pregnancy.

For women in poor nations, this compact regimen has a number of advantages, including its simple administration and its relatively low cost. Whilst discrete drug costs naturally do not reflect the additional costs involved in healthcare provision, the price of this three dose nevirapine regimen has been well-publicised – 25 South African Rand (which equates to two pounds fifty in Sterling, or around four US dollars). To put this in context, 290 million Africans survive on less than one US dollar per day.

Earlier this week Boehringer Ingelheim announced their intention to provide nevirapine free to all pregnant women in developing countries who could not afford to pay for the drug. Further details of this programme will be reported here on aidsmap.com in due course.