HIV drug resistance in persons initiating or reinitiating first-line antiretroviral therapy in Paraguay: Results of a National Patient Survey

Abstract

Human immunodeficiency virus (HIV) drug resistance increases mortality and morbidity and antiretroviral therapy (ART) costs. We describe Paraguay's first nationally representative survey on pretreatment drug resistance (PDR) conducted among persons who initiated or reinitiated ART in 2019. ​​​​We conducted a cross-sectional survey of antiretroviral (ARV) drug resistance in Paraguay in 2019. Participants were sampled at four comprehensive care clinics where 90% of patients with HIV in Paraguay initiate ART. Patients included were adults ≥18 years old who initiated first-line ART or reinitiated the same first-line ART regimen after ≥3 months of discontinuation. Of 208 patients, 93.8% had no prior ART exposure, 3.8% reinitiated the same regimen, 2.4% had unknown prior ART exposure; and 31.3% had a CD4 count <200 cells/µl. Mutations associated with resistance were present in 15.4% of patients. Mutations associated with resistance to nonnucleoside reverse transcriptase inhibitors (NNRTI) were present in 13.0% of patients, nucleoside reverse transcriptase inhibitors in 4.3%, and integrase inhibitors in 3.4%. Mutations associated with resistance to tenofovir were present in 1.0% of patients and emtricitabine/lamivudine in 1.4%. ​​Nearly one in six patients had PDR in Paraguay's first nationally representative sample. High NNRTI PDR prevalence underscores the need to accelerate the transition to dolutegravir-based first-line ART. The low PDR prevalence of tenofovir and emtricitabine is reassuring as these ARVs are part of the World Health Organization (WHO)-recommended oral pre-exposure prophylaxis regimen. The high proportion of individuals initiating ART at a late disease stage highlights the need to improve treatment linkage strategies and implement WHO rapid ART initiation recommendations.

Keywords: HIV; Paraguay; antiretroviral therapy; drug resistance; late treatment initiation.