21: Integrase strand transfer inhibitors given to HIV-infected women late in pregnancy decrease HIV viral load more quickly than other antiretroviral therapy (ART)


      Minimizing time to HIV viral suppression is critical in pregnancy. Integrase strand transfer inhibitors (INSTIs), like raltegravir, are known to rapidly suppress plasma HIV RNA in nonpregnant adults. We describe time to clinically relevant reduction in HIV RNA in pregnant women using INSTI-containing and non-INSTI-containing ART options.

      Study Design

      We conducted a retrospective cohort study of pregnant HIV-infected women in the U.S. from 2009 to 2015. We included women who initiated ART, intensified their regimen or switched to a new regimen due to detectable viremia (HIV RNA > 40c/mL) at > 20 weeks gestation. Among women with a baseline HIV RNA permitting 1-log reduction, we estimated time to 1-log RNA reduction using the Kaplan-Meier estimator comparing women starting/adding an INSTI in their regimen versus other ART. To compare groups with similar follow-up time, we also conducted a subgroup analysis limited to women with <14 days between baseline and follow-up RNA data.


      Maternal characteristics of 101 women from 11 U.S. clinics are shown in Table 1. 76/101 (75%) women were not taking ART at baseline. 39/101 (39%) women started/added an INSTI in their ART regimen. Among 90 women with a baseline HIV RNA permitting 1-log reduction, the median time to 1-log RNA reduction was 8 [IQR: 6, 14] days in the INSTI group versus 35 [IQR: 20, 53] days (p<0.001) in the non-INSTI ART group. In a subgroup of 39 women with first and last RNA measurements <14 days apart, median time to 1-log reduction was 7 [IQR: 6, 10] days in the INSTI group versus 11 [IQR: 10, 14] days (p=0.01) in the non-INSTI group. (Figure 1)


      ART that includes INSTIs appears to induce more rapid viral suppression than other ART regimens in pregnancy. Inclusion of an INSTI may play a role in optimal reduction of HIV-RNA for HIV-infected pregnant women presenting late to care or failing initial therapy. Larger studies are urgently needed to assess the safety and effectiveness of this approach.
      Figure thumbnail fx1
      Figure thumbnail fx2