Objective: To evaluate antiviral activity, tolerability, safety and pharmacokinetics of treatment with TMC125 (a non-nucleoside reverse transcriptase inhibitor), 900 mg twice daily for 7 days.
Design: Randomized, double-blind, placebo-controlled, phase IIA clinical trial.
Setting: Two hospital clinics in Moscow and St Petersburg, Russian Federation.
Participants: Nineteen antiretroviral-naive, HIV-1-infected subjects.
Interventions: Randomization (2:1) was to twice daily treatment with either 900 mg TMC125 or matched placebo as monotherapy for 7 days.
Main outcome measures: Change in plasma HIV-1 RNA from baseline values (primary); change in CD4 cell counts from baseline, and evaluation of safety, tolerability and pharmacokinetics of TMC125 treatment (secondary).
Results: A mean decrease from baseline in plasma HIV-1 RNA of 1.99 log10 copies/ml and 0.06 log10 copies/ml was achieved after 7 days in the TMC125 and placebo groups, respectively (P < 0.001). Plasma viral daily decay rates of 0.33 log10 copies/ml and 0.02 log10 copies/ml were observed in the TMC125 and placebo groups, respectively (P < 0.001). A steady-state plasma concentration of TMC125 was attained within 5 days of treatment with a mean minimum concentration of 246 ng/ml and a mean maximum concentration of 419 ng/ml. The majority of subjects did not report any adverse events. No abnormalities consistent with changes in blood chemistry, haematology, urinalysis, electrocardiograph or vital signs were observed.
Conclusions: TMC125 administered as monotherapy for 7 days yielded a 1.99 log10 copies/ml reduction in HIV-1 RNA in antiretroviral-naive, HIV-1-infected subjects. TMC125 was well tolerated and represents a promising and highly potent, next generation non-nucleoside reverse transcriptase inhibitor candidate.