Primary antiretroviral resistance in recently infected injection drug users and in drug naïve individuals.
authors
Alexander C, Dong W, Mo T, O'shaugnessy M, Schechter M, Montaner J, Harrigan PR.
publication
6th National Conference on HIV and Opportunistic Infections. 31 Jan-4 Feb 1999, Chicago, IL. Abstract 218.
ABSTRACT
Objective: To determine the frequency of mutations associated with primary resistance in two populations: drug naïve individuals starting treatment in British Columbia, and in injection drug using HIV seroconverters.
Design: The first arm of this study examined all individuals (N= 256) entering the BC HIV Drug Treatment program between 07/97 and 12/97. This program distributes antiretrovirals free of charge to all HIV infected people in British Columbia. We also examined all recent seroconverters (N=61) in the Vancouver Injection Drug Users Study (VIDUS) during a period of an explosive outbreak of HIV transmission. Plasma viral RNA was extracted and the viral reverse transcriptase (RT) and protease (PR) genes were amplified by nested RT-PCR. Mutations associated with resistance were assessed by automated sequence analysis (ABI) in both directions.
Results: From results obtained to date, in the general drug naïve population 7/189 (3.7%) had mutations associated with significant resistance to RT inhibitors and 2/221 (1.4%) with resistance to PR inhibitors. No mutations associated with significant resistance to RT or PR inhibitors (N=51 or 54 respectively) were observed in the intravenous drug using seroconverters.
Conclusions: The incidence of prior resistance to antiretrovirals is low in drug naïve patients in BC. The explosive outbreak of HIV infection among Vancouver injection drug users has not yet resulted in significant transmission of drug resistant HIV variants.
