Drug Discovery & Development
Idenix’s development program includes IDX899, a novel non-nucleoside reverse transcriptase inhibitor (NNRTIs) to treat HIV, which is currently in phase I/II clinical trials. NNRTIs are important components of effective antiretroviral therapy (ART) combination regimens for the treatment of HIV-1 infected individuals1.
In in-vitro preclinical studies, IDX899 has demonstrated potent antiviral activity, a favorable toxicology profile and potential for once-daily dosing. Also in-vitro, IDX899 exhibited potent activity against established NNRTI-resistant clinical isolates, and, compared to efavirenz, the emergence of IDX899-resistant HIV-1 isolates was slower and required several mutations suggesting a higher barrier to resistance for IDX899.
An ongoing phase I/II clinical trial is evaluating the safety, tolerability and antiviral activity of IDX899. In the first cohort of the study, ten HIV-1-infected treatment-naïve patients were randomized 8:2 to receive once-daily 800 mg IDX899 or matching placebo, respectively, for seven days. IDX899 produced a rapid and profound reduction in virus level in this cohort and there were no reported serious adverse events and no patient discontinuations. Given the potent antiviral activity and favorable preliminary safety demonstrated at 800 mg once-daily, Idenix will explore sequential cohorts of 400 mg once-daily followed by 200 mg once-daily.
1 Guidelines for the Use of Antiretroviral Agents in HIV-1-Infected Adults and Adolescents, DHHS Panel on Antiretroviral Guidelines for Adults and Adolescents
XVII International Drug Resistance Workshop Materials
6.12.08 Idenix
HIV Drug Resistance Press Release
Murphy et al,
HIV Drug Resistance Workshop June 12, 2008 Presentation