The potential for treatment shortening with higher rifampicin doses : relating drug exposure to treatment response in patients with pulmonary tuberculosis
Abstract
Background: Tuberculosis remains a huge public health problem and the prolonged treatment duration obstructs effective tuberculosis control. Higher rifampicin doses have been associated with better bactericidal activity, but optimal dosing is uncertain. This analysis aimed to characterize the relationship between rifampicin plasma exposure and treatment response over 6 months in a recent study investigating the potential for treatment shortening with high-dose rifampicin. Methods: Data were analyzed from 336 patients with pulmonary tuberculosis (97 with pharmacokinetic data) treated with rifampicin doses of 10, 20, or 35 mg/kg. The response measure was time to stable sputum culture conversion (TSCC). We derived individual exposure metrics with a previously developed population pharmacokinetic model of rifampicin. TSCC was modeled using a parametric time-to-event approach, and a sequential exposure-response analysis was performed. Results: Higher rifampicin exposures increased the probability of early culture conversion. No maximal limit of the effect was detected within the observed range. The expected proportion of patients with stable culture conversion on liquid medium at week 8 was predicted to increase from 39% (95% confidence interval, 37%-41%) to 55% (49%-61%), with the rifampicin area under the curve increasing from 20 to 175 mg/L·h (representative for 10 and 35 mg/kg, respectively). Other predictors of TSCC were baseline bacterial load, proportion of culture results unavailable, and substitution of ethambutol for either moxifloxacin or SQ109. Conclusions: Increasing rifampicin exposure shortened TSCC, and the effect did not plateau, indicating that doses >35 mg/kg could be yet more effective. Optimizing rifampicin dosage while preventing toxicity is a clinical priority.
Citation
Svensson , E M , Svensson , R J , Te Brake , L H M , Boeree , M J , Heinrich , N , Konsten , S , Churchyard , G , Dawson , R , Diacon , A H , Kibiki , G S , Minja , L T , Ntingiya , N E , Sanne , I , Gillespie , S H , Hoelscher , M , Phillips , P P J , Simonsson , U S H & Aarnoutse , R 2018 , ' The potential for treatment shortening with higher rifampicin doses : relating drug exposure to treatment response in patients with pulmonary tuberculosis ' , Clinical Infectious Diseases , vol. 67 , no. 1 , pp. 34-41 . https://doi.org/10.1093/cid/ciy026
Publication
Clinical Infectious Diseases
Status
Peer reviewed
ISSN
1058-4838Type
Journal article
Rights
© The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. DOI: 10.1093/cid/ciy026
Description
This work was supported by the European and Developing Countries Clinical Trials partnership (grants IP.2007.32011.011, IP.2007.32011.012, and IP.2007.32011.013) and the German Ministry for Education and Research (grant 01KA0901). The original study conducted within the PanACEA consortium.Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.