Emergence of HIV-1 drug-resistant variants in women following antiretroviral prophylaxis for the prevention of mother to child transmission.

PURPOSE: Emergence of drug resistance following HIV prophylaxis has an important impact on ART program.

OBJECTIVE

To investigate the emergence of drug resistance in HIV-1 infected pregnant women.

MATERIALS AND

METHODS

Fifty-three HIV-1 infected pregnant women who had received 4-12 weeks of antenatal AZT followed by Nevirapine during delivery and Combivir [AZT + 3TC] for 1 week postpartum (group-1, n = 48) or who come at the time of delivery and received Nevirapine followed by Combivir for 1 week (group-2, n = 5) were recruited. Samples were collected prior to the start of the prophylaxis and 5-8 weeks postpartum. In addition, a third sample was collected between 26-65 weeks postpartum from 7 women. Amplification of HIV-1 pol gene and drug resistance analysis was done.

RESULT: Two (3.8%) women in group-1 showed transmitted drug resistance and they continued to show this even at 6 weeks postpartum. One (2%) woman from group-1 showed a mutation after 6-8 weeks of prophylaxis. Among the samples collected between 26-65 weeks postpartum, 3/7 (43%) showed mutations and all these women belong to group-1. Women belonging to group-2 didn't show mutation prior to or following prophylaxis.

CONCLUSION

In contrast to the available data among pregnant women with ART prophylaxis, our data showed reduced frequency of mutations following 5-8 weeks of postpartum but an emergence of mutation later (26-65 weeks). The addition of Combivir with the single dose Nevirapine during delivery and the early stage of the disease with higher CD4 counts could be the reasons for this.