Integrase strand transfer inhibitors resistance-associated mutations in HIV-infected pregnant women.

Objective: To date, no data exist regarding the prevalence of integrase inhibitor (INSTI) resistance-associated mutations (HIVDRM) in HIV-infected pregnant women (HPW) in Latin America. We describe the prevalence and transmissibility of integrase HIVDRM in a historical cohort of INSTI-naïve HPW from Argentina (n=56) with Next Generation Sequencing (NGS).

Methods: Bioinformatics analysis was performed by HyDRA software for 20%, 10%, 5%, 2%, and 1% sensitivity thresholds. We calculated the mutational viral load for each INSTI-HIVDRM, considering those with >1000 c/mL as of high risk of transmissibility.

Results: The predominant HIV subtype was BF (78.5%). Major HIVDRM were not detected with the population sequencing 20% filter. With a 1% threshold, the prevalence increased to 8.9%; Y143C/S, E92G, E138K, and T66I mutations were found. The median (range) mutational load (expressed in c/mL) was: 355 (50.2-11705); with only 1 case >1000 c/mL Accessory mutations (G163R/K, T97A) were detected mostly with a 20% sensitivity threshold with an overall prevalence of 23.2%; the median (IQR) mutational load was: 23929 (4009-63158) c/mL; all of them above 1000 c/mL.

Conclusions: Our results show evidence of the presence of major INSTI-HIVDRM as aleatory mutations and a high frequency of accessory mutations with potential transmissibility in HPW.