Efficacy of macozinone in mice with genetically diverse susceptibility to Mycobacterium tuberculosis infection

Microbes Infect. 2024 Nov-Dec;26(8):105376. doi: 10.1016/j.micinf.2024.105376. Epub 2024 Jun 7.

Abstract

Host heterogeneity in pulmonary tuberculosis leads to varied responses to infection and drug treatment. The present portfolio of anti-TB drugs needs to be boosted with new drugs and drug regimens. Macozinone, a clinical-stage molecule targeting the essential enzyme, DprE1, represents an attractive option. Mice (I/St, B6, (AKRxI/St)F1, B6.I-100 and B6.I-139) genetically diverse susceptibility to Mycobacterium tuberculosis (Mtb) H37Rv infection were subjected to aerosol- or intravenous infection to determine the efficacy of macozinone (MCZ). They were treated with macozinone or reference drugs (isoniazid, rifampicin). Lung and spleen bacterial burdens were measured at four and eight weeks post-infection. Lung histology was evaluated at four weeks of treatment. Treatment with macozinone resulted in a statistically significant reduction in the bacterial load in the lungs and spleen as early as four weeks after treatment initiation in mice susceptible or resistant to Mtb infection. In the TB hypoxic granuloma model, macozinone was more potent than rifampicin in reducing the CFU counts. However, histopathological analysis revealed significant lung changes in I/St mice after eight weeks of treatment initiation. Macozinone demonstrated efficacy to varying degrees across all mouse models of Mtb infection used. These results should facilitate its further development and potential introduction into clinical practice.

Keywords: Antitubercular agents; Benzothiazinones; Comparative analysis; Tuberculosis.

MeSH terms

  • Animals
  • Antitubercular Agents* / pharmacology
  • Antitubercular Agents* / therapeutic use
  • Bacterial Load* / drug effects
  • Disease Models, Animal
  • Female
  • Genetic Predisposition to Disease
  • Isoniazid / pharmacology
  • Isoniazid / therapeutic use
  • Lung* / microbiology
  • Lung* / pathology
  • Mice
  • Mice, Inbred C57BL
  • Mycobacterium tuberculosis* / drug effects
  • Mycobacterium tuberculosis* / genetics
  • Rifampin / pharmacology
  • Rifampin / therapeutic use
  • Spleen* / microbiology
  • Spleen* / pathology
  • Treatment Outcome
  • Tuberculosis / drug therapy
  • Tuberculosis / microbiology
  • Tuberculosis, Pulmonary / drug therapy
  • Tuberculosis, Pulmonary / microbiology
  • Tuberculosis, Pulmonary / pathology

Substances

  • Antitubercular Agents
  • Rifampin
  • Isoniazid