Effect of Integrase Strand Transfer Inhibitor Use on Time to HIV Viral Suppression before Delivery

We sought to determine whether pregnant individuals with human immunodeficiency virus (HIV) prescribed integrase strand transfer inhibitor (INSTI) antiretrovirals (ARVs) achieve viral suppression faster than individuals taking non-INSTI regimens and to determine whether there were differences in viral suppression at delivery among INSTI ARVs.

This is a retrospective cohort study of pregnant individuals with HIV who delivered a live infant during the study period (January 1, 2009-December 31, 2020). Patients' ARV therapy (ART) was classified as including INSTI or non-INSTI. We compared the proportion of individuals with viral suppression at delivery by group and individual INSTI ARVs using χ² and Fisher exact tests. A log rank test was used to compare time to viral suppression on ARVs.

During the study period, 168 individuals delivered a live infant. Most of the patients were diagnosed as having HIV before pregnancy and had taken ARVs before conception (76%), but fewer than half had an undetectable viral load at the first antenatal visit (45%). During pregnancy, 46% were prescribed INSTI and 54% were prescribed non-INSTI ARVs. Most had an undetectable HIV RNA viral load at delivery (75% INSTI and 72% non-INSTI, P = 0.7). The time to viral suppression was similar between groups (log rank test P = 0.43). Viral suppression at delivery was similar among INSTI ARVs: raltegravir (53%), elvitegravir (88%), dolutegravir (73%), and bictegravir (88%) (P = 0.13).

Despite recommendations to prescribe INSTI in pregnancy for rapid viral suppression, we did not find a significant difference in time to viral suppression when pregnant individuals were taking non-INSTI ARVs. We did not find that one INSTI ARV was superior for viral suppression.