The Diarylquinoline TMC207 for Multidrug-Resistant Tuberculosis

Abstract

BACKGROUND The diarylquinoline TMC207 offers a new mechanism of antituberculosis action by inhibiting mycobacterial ATP synthase. TMC207 potently inhibits drug-sensitive and drug-resistant Mycobacterium tuberculosis in vitro and shows bactericidal activity in patients who have drug-susceptible pulmonary tuberculosis. METHODS In the first stage of a two-stage, phase 2, randomized, controlled trial, we randomly assigned 47 patients who had newly diagnosed multidrug-resistant pulmonary tuber- culosis to receive either TMC207 (400 mg daily for 2 weeks, followed by 200 mg three times a week for 6 weeks) (23 patients) or placebo (24 patients) in combination with a standard five-drug, second-line antituberculosis regimen. The primary efficacy end point was the conversion of sputum cultures, in liquid broth, from positive to negative. RESULTS The addition of TMC207 to standard therapy for multidrug-resistant tuberculosis re- duced the time to conversion to a negative sputum culture, as compared with placebo (hazard ratio, 11.8; 95% confidence interval, 2.3 to 61.3; P = 0.003 by Cox regression analysis) and increased the proportion of patients with conversion of sputum culture (48% vs. 9%). The mean log10 count of colony-forming units in the sputum declined more rapidly in the TMC207 group than in the placebo group. No significant dif- ferences in average plasma TMC207 concentrations were noted between patients with and those without culture conversion. Most adverse events were mild to mod- erate, and only nausea occurred significantly more frequently among patients in the TMC207 group than among patients in the placebo group (26% vs. 4%, P = 0.04). CONCLUSIONS The clinical activity of TMC207 validates ATP synthase as a viable target for the treat- ment of tuberculosis. (ClinicalTrials.gov number, NCT00449644.) n