Debio 1453 is a potent bactericidal FabI inhibitor that is effective against Neisseria gonorrhoeae (IC50 = 0.6 nM) as well as its resistant strains. By inhibiting FabI and binding the non-mutatable NADH cofactor, Debio 1453 demonstrates a low propensity for resistance selection and effectively targets both planktonic and intracellular bacteria. It is capable of eradicating resistant Neisseria gonorrhoeae infections in a mouse vaginal infection model. Debio 1453 can be utilized in gonorrhea-related research.

Debio 1453 demonstrates activity against 2024 WHO reference strains of Neisseria gonorrhoeae, including strains resistant to Ceftriaxone, Azithromycin, Spectinomycin, Tetracycline, and Ciprofloxacin, with an MIC range of 0.03-0.125 μg/mL. It exhibits potent in vitro activity against 100 contemporary clinical Neisseria gonorrhoeae isolates (MIC 50 / MIC 90 = 0.06 μg/mL), with an MIC range of 0.008 to 0.125 μg/mL. Debio 1453 rapidly kills Neisseria gonorrhoeae in a time-dependent manner (0-16 times MIC, 0-24 hours), effectively eliminating both antibiotic-sensitive and extensively drug-resistant (XDR) strains. In vivo, Debio 1453 (0-8 times MIC, 0-24 hours) reduces bacterial counts of antibiotic-sensitive Neisseria gonorrhoeae (ATCC 49226) and resistant strains (WHO X) to below detectable levels within 24 hours (by ≥3.1 log10 CFU/mL and ≥2.8 log10 CFU/mL, respectively). Its low potential for selecting resistant mutants in vitro at 4-16 times MIC confirms FabI as a target. Furthermore, Debio 1453 (0.3-30 μM, 24 hours) shows no cytotoxicity or negative impact on cell viability in HepG2 cells and does not exhibit clastogenic or aneugenic toxicity in lymphocytes, regardless of the presence of a rat liver metabolic activation system.

Debio 1453, administered as the prodrug Debio 1453 P (10-160 mg/kg, orally, twice daily for 2 days), demonstrates potent antibacterial activity in both a Neisseria gonorrhoeae vaginal infection model and a Staphylococcus aureus thigh infection model in mice.