Multicentric in-vitro characterization of MPL-204, a new anti- tuberculosis drug candidate, by the ERA4TB collaborative initiative

Ramón García, Santiago
TUBERCULOSIS 2022 - EMBO Workshop on Tuberculosis 2022 - From innovation to intervention
Participation type: 
Other authors: 
M. Dal Molin, M. Eveque, S. De Giorgi, L. Cioetto Mazzabò, C. Zavala Alvarado, D. Aguilar Ayala, E. Hoffmann, G. Degiacomi, D. Recchia, L. Chiarelli, L. Chhen, B. Dremierre, M. Boutrois, A. Leding, B.O. Susanto, U.S.H. Simonsson, M.R. Pasca, A. Baulard, A. Lucía Quintana, S. Ramón García, G. Manina, R. Manganelli, N. Willand, J. Rybniker, N. Serbina, N. Fotouhi, C. Gaudin
Paris, France. Sep 12-16 2022

The development of new anti-tuberculosis compounds with novel mechanisms of action is still a slow and cost-consuming challenge. One of the goals of the IMI2-funded EUROPEAN REGIMEN ACCELERATOR FOR TUBERCULOSIS (ERA4TB), which aims to boost the development of new therapeutic regimens for the treatment of tuberculosis, is to accelerate this process through collective efforts of various teams with different expertise in drug development.
The in-vitro characterization of new tuberculosis drug candidates, combined with pharmacokinetic/pharmacodynamic data generation, is crucial in order to understand the multiparametric mechanisms involved in patients. The development of appropriate assays and models is a pre-requisite to provide valuable information and to predict activity and efficacy in vivo as well as in clinical trials, but also to anticipate and understand the response and potential defence mechanisms adopted by drug-resistant strains.
Here, this collaborative effort is illustrated through the in-vitro characterization of a novel indole carboxamide drug candidate, developed by TB Alliance, targeting the mycobacterial membrane protein large 3 (MmpL3) transporter, whose central role in cell envelope biogenesis has been validated as a promising therapeutic target. By combining traditional assays and cutting edge tools in drug development, we report comprehensive characterization of this novel candidate with respect to: I) time kill kinetics combined with drug quantification by LC-MS/MS analysis; II) determination of the frequency of resistance using standard in-vitro fluctuation analysis followed by whole genome sequencing of resistant mutants; III) assessment of the effect of the drug on the biosynthesis of mycobacterial lipids; IV) study of the impact of the proton motive force as well as single carbon sources on drug activity, and V) evaluation of the activity of the drug in the novel human ex-vivo model of granuloma-like structures during Mycobacterium tuberculosis infection. Moreover, the artificial caseum model was used to determine the drug penetration properties of this compound.
Altogether, we describe a multicentric collaborative approach that can fuel modelling predictions, and support progression of promising drug candidates and combinations to the clinic.
This work has received support from the Innovative Medicines Initiatives 2 Joint Undertaking (grant No 853989).