CLSI Grants High Susceptibility Breakpoints To Zaynich For Resistant Infections

The Clinical and Laboratory Standards Institute (CLSI), a globally renowned US organisation, has awarded high susceptibility breakpoints to Zaynich (Zidebactam/Cefepime- WCK 5222) during its plenary session on June 24, 2024, the institute informed in a press statement on Monday.

Zaynich has been granted a susceptibility breakpoint of 64 mg/L for approximately ten Gram-negative pathogens that exhibit high resistance rates. These breakpoints guide physicians in selecting the most effective antibiotics for treating various infections caused by different pathogens.

This high breakpoint signifies Zaynich’s strong potential to combat all clinically important, extremely drug-resistant Gram-negative pathogens in critically ill patients. Since the discovery of penicillin in 1928, over 250 antibiotics have been approved for clinical use, but this is the first time an antibiotic has received a susceptibility breakpoint of 64 mg/L for the three major families of Gram-negative pathogens: Enterobacterales, Pseudomonas, and Acinetobacter.

Pending formal approval, CLSI has designated these breakpoints as Investigational Breakpoints to support clinical trials and the compassionate use of Zaynich, a vital antibiotic. Over eight years of research data on Zaynich were meticulously reviewed by three CLSI sub-committees, followed by independent voting rounds. The final plenary session unanimously approved the investigational breakpoints for Zaynich.

In the past year, Zaynich has successfully treated 30 patients under compassionate use protocols. These patients were suffering from infections caused by extremely drug-resistant Gram-negative pathogens, including Pseudomonas, Klebsiella, E. coli, Acinetobacter, and Serratia, which were not responsive to any available antibiotics. The high breakpoints assigned to Zaynich have supported consistent clinical cures and microbiological eradications in these compassionate use cases.

Currently, Zaynich is undergoing a multinational Phase 3 study, expected to be completed by the fiscal year 2025. This study is anticipated to facilitate Zaynich’s global registration and marketing authorization, offering hope to patients worldwide, the statement added.