IMPAACT P1078 at CROI 2018

The International Maternal Pediatric Adolescent AIDS Clinical Trials (IMPAACT) Network is delighted to announce the presentation of the study results and important findings from IMPAACT P1078 (TB APPRISE), a phase IV, randomized, double-blind, placebo-controlled trial to evaluate the safety of immediate versus deferred isoniazid preventive therapy (IPT) among HIV-infected women in high tuberculosis (TB) incidence settings, at the 2018 annual Conference on Retroviruses and Opportunistic Infections (CROI) in Boston, Massachusetts.

The World Health Organization (WHO) currently strongly recommends IPT for at least six months for children and adults living with HIV, including pregnant women, to prevent active TB disease. Mothers with HIV were randomly assigned, in pairs with their infants, to receive 28 weeks of IPT either beginning during pregnancy (immediate) or beginning at 12 weeks after delivery (deferred). The study hypothesized that beginning IPT during pregnancy was non-inferior to beginning IPT after pregnancy. Results presented at CROI 2018 are described below and the associated presentation will be posted on the IMPAACT website in the near future.

IMPAACT P1078 enrolled 956 mother-infant pairs across 13 IMPAACT sites in Botswana, Haiti, India, South Africa, Tanzania, Thailand, Uganda, and Zimbabwe. All mothers were receiving antiretrovirals (ARVs) at study entry and most mothers had an undetectable viral load.

Primary analyses of the study, presented by Amita Gupta on behalf of the P1078 protocol team, indicated that the study was not able to conclude that antepartum IPT is as safe as postpartum IPT, in part because endpoints among mothers were higher than expected in both arms. There were no statistically significant differences between arms in the number of mothers or infants who had grade 3 or higher adverse events, in the number of mothers who had hepatotoxicity events from any cause, or in the number of mothers or infants who died during the study. Incidence of tuberculosis for mothers and infants was low and comparable between arms.

There was a statistically significant difference of adverse pregnancy outcomes between mother-infant pairs randomized to IPT during pregnancy and mother-infant pairs randomized to IPT after delivery, with more adverse pregnancy outcomes among pairs randomized to IPT during pregnancy.

Based on these results, the protocol team concluded that the WHO recommendation to initiate IPT during pregnancy in women with HIV who are on antiretroviral therapy may need re-evaluation.

For more information about IMPAACT P1078, visit impaactnetwork.org/studies/P1078 or contact IMPAACTops@fhi360.org.