# A bactericidal tuberculosis drug regimen driven by inhibition of the terminal oxidases by pretomanid

## TL;DR

Pretomanid, a tuberculosis drug, works by partially inhibiting key energy-producing enzymes in bacteria, and combining it with other drugs improves its effectiveness and reduces resistance.

## Contribution

Pretomanid's dual inhibition of terminal oxidases is revealed, enabling a synergistic drug combination for tuberculosis.

## Key findings

- Pretomanid partially inhibits both cytochrome bcc:aa3 and bd oxidases in M. tuberculosis.
- Combining pretomanid with telacebec and a cytochrome bd inhibitor achieves rapid bactericidal activity and resistance suppression.
- The triple drug combination effectively targets both replicating and non-replicating M. tuberculosis in vitro.

## Abstract

Pretomanid is a unique anti-tuberculosis agent that inhibits both cell-wall synthesis and bioenergetics in Mycobacterium tuberculosis. While targeting the cell wall triggers a rapid bactericidal effect on replicating mycobacteria, the release of nitric oxide is linked to bactericidal potency against antibiotic-tolerant, non-replicating subpopulations through interference with the electron transport chain. Nonetheless, the specific molecular target(s) of the drug remain unknown. Through the utilization of genetic and chemical biology approaches, we present evidence that pretomanid inhibits both the cytochrome bcc:aa3 and bd oxidase respiratory branches. This property leads to a pronounced synergy with telacebec (Q203), a clinical-stage drug targeting the cytochrome bcc:aa3, while concurrently curtailing the emergence of resistance to pretomanid. Furthermore, the incorporation of the cytochrome bd oxidase inhibitor ND-011992 resulted in a triple drug combination highly bactericidal against antibiotic-tolerant, non-replicating as well as replicating M. tuberculosis. The combination of pretomanid and drugs targeting the terminal oxidases holds the potential to serve as the cornerstone for an efficacious sterilizing drug regimen against tuberculosis.

Pretomanid partially inhibits both terminal oxidases in M. tuberculosis, revealing a vulnerability that can be exploited in combination therapy. Pairing pretomanid with telacebec and a cyt-bd inhibitor achieves a rapid bactericidal activity, resistance suppression, and in vivo efficacy, supporting terminal oxidase inhibition as a promising backbone for new TB regimens.

Pretomanid inhibits partially both cytochrome bcc:aa3 and bd oxidases in M. tuberculosis.Q203 boosts pretomanid potency and prevents resistance.Triple combination pretomanid + Q203 + cytochrome bd inhibitor sterilizes replicating and non-replicating bacilli in vitro.Drugs targeting the terminal oxidases combined with pretomanid represent a promising drug regimen for TB.

Pretomanid inhibits partially both cytochrome bcc:aa3 and bd oxidases in M. tuberculosis.

Q203 boosts pretomanid potency and prevents resistance.

Triple combination pretomanid + Q203 + cytochrome bd inhibitor sterilizes replicating and non-replicating bacilli in vitro.

Drugs targeting the terminal oxidases combined with pretomanid represent a promising drug regimen for TB.

Pretomanid partially inhibits both terminal oxidases in M. tuberculosis, revealing a vulnerability that can be exploited in combination therapy. Pairing pretomanid with telacebec and a cyt-bd inhibitor achieves a rapid bactericidal activity, resistance suppression, and in vivo efficacy, supporting terminal oxidase inhibition as a promising backbone for new TB regimens.