Maintenance darunavir/ritonavir monotherapy was effective in the prevention of perinatal HIV transmission in a recent study; however, about 10% of the cases required treatment intensification.
Nucleoside reverse transcriptase inhibitors (NRTIs) are associated with drug-related toxicities in both fetal and neonatal stages. However, despite known toxicities, NRTIs are recommended for neonatal prophylaxis against HIV during pregnancy.
This study evaluated the proportion of maintenance darunavir/ritonavir monotherapy required to maintain the viral load below 50 copies/mL without the need to intensify treatment. The findings are published in the Journal of Antimicrobial Chemotherapy.
This clinical trial included a total of 91 women, of whom 81 were on darunavir/ritonavir-based regimens at baseline and switched to maintenance darunavir/ritonavir monotherapy, whereas the remaining 10 were not on darunavir/ritonavir at the start of their pregnancies and switched to darunavir/ritonavir-based triple therapy for 2 weeks before discontinuing the NRTI component. Four of the 89 women who initiated maintenance darunavir/ritonavir monotherapy had miscarriages prior to 22 weeks of gestation.
High Success Rate for Maintenance Darunavir/Ritonavir Monotherapy
Treatment intensification was performed in 6 of the 83 women due to virological failure, as indicated by the median viral load of 193 copies/ml. The success rate of maintenance darunavir/ritonavir monotherapy after excluding these six cases as failures was 90.4%, which was not significantly different compared to the minimum success rate of 85%.
Effective Tenofovir/Emtricitabine Treatment Intensification in CD4-Compromised Women Without Resistance Mutations
The treatment intensification included the addition of tenofovir disoproxil fumarate/emtricitabine, which yielded successful results in all six patients. These women had lower levels of CD4 cell count at baseline. There was no evidence of resistance-associated mutations in these patients. The treatment adherence issues were not significantly different in these patients compared to patients with maintained virological success.
Maintenance Darunavir/Ritonavir Monotherapy Pharmacological Outcomes
The plasma concentrations of darunavir remained stable throughout the pregnancy period following the administration of maintenance darunavir/ritonavir monotherapy.
Adverse Effects and Pregnancy Outcomes on Maintenance Darunavir/Ritonavir Monotherapy
Of the total number of women administered a maintenance darunavir/ritonavir monotherapy regimen, 2 experienced intolerance, and 10 reported elevated liver enzymes. Of the latter, three cases constituted pregnancy-related complications. The rates of preterm delivery and birth defects were approximately 9.5% and 3.6%, respectively.
Mandelbrot, L., Tubiana, R., Frange, P., Peytavin, G., Chenadec, J. L., Canestri, A., Morlat, P., Brunet-Cartier, C., Sibiude, J., Peretti, D., Chambrin, V., Chabrol, A., Bui, E., Simon-Toulza, C., Marchand, L., Paul, C., Delmas, S., Avettand-Fènoël, V., Warszawski, J., . . . Arezes, E. (2023). Maintenance darunavir/ritonavir monotherapy to prevent perinatal HIV transmission, ANRS-MIE 168 MONOGEST study. Journal of Antimicrobial Chemotherapy, 78(7), 1711–1722. https://doi.org/10.1093/jac/dkad161