A report on Moira Wilson's Pregnancy and women living with HIV, current guidelines and changes presentation

This session focused on dilemmas in prescribing ART to pregnant women living with HIV in the context of a paucity of strong evidence/evolving evidence to guide clinical decision making.

Careful history taking and engaging women living with HIV in ART treatment decisions in order to optimise management (with the key goal of viral load suppression) is crucial. Treatment decisions will be different for women planning to conceive and women who aren’t, which is where engagement is key. For example, in women planning to conceive (or who are pregnant) safety issues in relation to the infant need to be considered. These include reducing the risk of vertical transmission by suppressing viral load in the mother and assessing the teratogenic potential of ART. In a planned pregnancy, older ART drugs with a better-known safety profile tend to be preferred. If the woman has no intention of conceiving or has effective contraception, the range of usual first line ART choices (including dolutegravir, bictegravir) can be offered.

Moira also presented emerging data from a research project, Tsepamo, in Botswana identifying a possible link between neural tube defects (NTDs) and dolutegravir in early pregnancy. Tsepamo (a prospective study designed to identify any NTDs associated with efavirenz) unexpectedly found a signal linked to dolutegravir. In March 2018 it was reported that women taking dolutegravir at conception were associated with 4/596 NTDs (against a background risk NTD 1/1000). The evidence was inconclusive due to the small study numbers and confounding variables (such as the fact that pregnant women in Botswana do not take folate in the first trimester).

The study was subsequently expanded aiming at including 72% of national births. In March 2019 the rate of NTDs was reported as 5/1683, lower than initially signalled, however still elevated compared with background risk. There was no significant difference in major external structural malformations in DTG vs non DTG ART.

Considering this possible link to NTDs, the current recommendation in Australian guidelines is to avoid dolutegravir in the first 8 weeks of pregnancy (however it is considered safe to use in the second and third trimester).  The World Health Organisation (WHO) in contrast recently updated their recommendations reconfirming use of DTG as preferred first- and second-line therapy with the underlying premise that the benefits in resource poor settings outweighed the risk.

The current Australian Preferred ART regime in pregnancy is 2 NRTIs e.g. TDF FTC, plus darunavir (twice daily dosing) or atazanavir (once daily) boosted by ritonavir or raltegravir (twice daily dosing) or efavirens or rilpivirine. It is advised to avoid drugs with no safety data in pregnancy such as cobistat, bictegravir, elvitegravir, TAF.

Ongoing vigilance in relation to the evolving ART guidelines for women (especially in the context of pregnancy) is recommended as the evidence base to inform clinical decisions emerges.

 

Nanette Presswell is an experienced general practitioner who has worked in a broad range of culturally diverse, public health oriented, primary health care services. She has worked in HIV primary care over the last 30 years, and for the last 10 years worked at Centre Clinic, a high case load HIV primary care clinic, Thorne Harbour Health.