Scientists have long been searching for an alternative to Nevirapine, a cheap and highly effective drug used to prevent the transmission of the HI-virus from the pregnant mother to her child during birth.

The urgent search is mainly precipitated by the fact that up to two thirds of women become resistant to the drug should they need it later when they access anti-retroviral therapy, consisting of three drugs and Nevirapine often being one of the preferred options.

Presentations at the 12th Annual Retrovirus Conference in Boston last week showed that various drug combinations recorded low rates of resistance, offering a relatively inexpensive and simple-to-take alternative for women.

Two studies, one in the Ivory Coast and the other in Botswana, reduced transmission rates at four to six weeks after birth to about five percent. Nevirapine in single dose reduces the transmission from 36 percent to 12 percent.

In the Ivory Coast study, researchers used single dose Nevirapine in 329 women and coupled it with AZT and 3TC, sold as a combination drug called Combivir. The Combivir was given to the mothers during pregnancy and for three days after birth. The newborns were given single-dose Nevirapine and AZT.

The results revealed that at six weeks, less than five percent of the babies were infected while only one percent of the mothers became resistant to Nevirapine and eight percent to 3TC.

In the Botswana study of 1 179 births, mothers were given multi-week AZT alone and in combination with single dose Nevirapine.

However, Dr Marc Isaac, vice-president at the Elizabeth Glaser Paediatric Foundation in Washington, warned that it was essential to preserve single-dose Nevirapine as an option when more complex regimens are unavailable.

In a statement, the Foundation said it was important to understand that clinical studies had demonstrated that all anti-retroviral drugs were associated with some level of resistance.

The statement cautioned that the clinical significance of the Nevirapine findings was still unclear and that the data warranted further study, something the Foundation was actively pursuing.

The Foundation said further that at an absolute minimum, all women should have access to single-dose Nevirapine, ‘€œwhich has proven safe and effective in numerous clinical trials and in practice at sites around the world’€.

Dr Fareed Abdullah, deputy director-general for District Health Services and Programmes in the Western Cape, said they had ‘€œquietly stopped using single-dose Nevirapine’€.

A CD4 count test is conducted on every HIV positive pregnant woman presenting at Government sites. Those with a CD count greater than 200 after offered two drugs ‘€“ The woman is given AZT from 34 weeks as well as single dose Nevirapine.

The baby is given single dose Nevirapine at birth and a seven-day course of AZT.

The drug is administered on site at the clinic or hospital.

‘€œThis intervention has increased drug uptake from between 60 and 70 percent to well over 90 percent and blocked most transmissions,’€ said Abdullah.

The other group of women – with CD4 counts of less than 200 – are immediately placed on triple therapy. ‘€œThis has cut transmission to less than five percent,’€ said Abdullah.

Abdullah said the province was hoping to get answers on whether they needed to combine Nevirapine with Combivir in some instances and whether they should administer AZT at 28 weeks as opposed to the current 34 weeks.

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