Characteristics Of Hiv-1 Pretreatment Drug Resistance And Its Impact On Combined Antiretroviral Therapy In Beijing

Background From 2013, the expanded strategies for the initial of combined antiretroviral therapy (cART) were administrated in Beijing to the infected individuals whatever their CD4 cell counts, hence, the increasing trend of HIV-1 epidemic has been alleviated. Pretreatment drug resistance was monitored, yet its impact on cART and the derivation of acquired drug resistance should be well delineated. Methods Treatment-naive individuals with HIV-1 were recruited from September 2012 to April 2013 in Beijing You’an Hospital. The patients were followed up after the initial of cART. HIV-1 pol gene fragment was amplified using One-Step RT-PCR at stage of pretreatment and follow-up virological failure. The genotypic drug resistance was interpreted with Stanford University HIV Drug Resistance Database, with CPR algorithm and HIVdb program. The genotypes were determined using MEGA6.0 after multiple alignment by gene cutter, with reference to BLAST and RIP. Results Totally, 324 treatment-naive infections were recruited, and about 272 cases (84.0%) were infected via MSM. The top three subtypes or CRFs were CRF01_AE (60.5%), CRF07_BC (18.5%) and B (15.4%). 13 individuals were observed to possess PDR (4.0%), at a low prevalence. The accumulative rate of virological failure was 9.5%, which were observed in 31 cases, and the cohort maintenance rate of 75.4%. The PDR induced virlological failure to develop acquired drug resistance (ADR) in three individuals, at a contributive rate of 23.1%. Some persons gained virological failure at 0.3–0.6 years post cART. Lower CD4 cell counts were prone to accompanied with the majority of virolgical failure (23.3%). The dynamic fluctuation of acquired drug resistance were observed by single genome amplification. Conclusion There was a low prevalence of transmitted drug resistance in treatment-naive individuals in Beijing, and the TDR might convey 23% virological failure. The first-line cART obtained good performance of virological suppression, and the virological failure would be rectified by shift to second-line cART. Disclosure No significant relationships.