Month 2 Culture Status and Treatment Duration as Predictors of Tuberculosis Relapse Risk in a Meta-Regression Model

BackgroundNew drugs and regimens with the potential to transform tuberculosis treatment are presently in early stage clinical trials.ObjectiveThe goal of the present study was to infer the required duration of these treatments.MethodA meta-regression model was developed to predict relapse risk using treatment duration and month 2 sputum culture positive rate as predictors, based on published historical data from 24 studies describing 58 regimens in 7793 patients. Regimens in which rifampin was administered for the first 2 months but not subsequently were excluded. The model treated study as a random effect.ResultsThe model predicted that new regimens of 4 or 5 months duration with rates of culture positivity after 2 months of 1% or 3%, would yield relapse rates of 4.0% or 4.1%, respectively. In both cases, the upper limit of the 2-sided 80% prediction interval for relapse for a hypothetical trial with 680 subjects per arm was ConclusionsThis model is proposed to inform the required duration of treatment of new TB regimens, potentially hastening their accelerated approval by several years.