Ceftolozane/Tazobactam for the Treatment of Adults With Cystic Fibrosis: Results From a French Prospective Cohort Study.

Background: People with cystic fibrosis (pwCF) are particularly susceptible to respiratory infections, including those caused by multidrug-resistant (MDR) pathogens. Ceftolozane/tazobactam (C/T) is an antibacterial agent combination active against MDR gram-negative bacteria that has shown promising results in isolates from pwCF. This subanalysis is the first extensive observation of real-world C/T use in pwCF.

Methods: The multicenter observational CONDUCT study included consecutive patients, some with cystic fibrosis, who received ≥1 dose of C/T at 28 centers throughout France. Patients were treated according to hospital standards and followed up until the end of C/T treatment (EOT).

Results: Among 260 patients who had received ≥1 dose of C/T, 63 were pwCF, including 12 with previous lung transplant. The median age was 34 years and 55.6% of patients were female. was the most frequently isolated pathogen (n = 40/41 [97.6%]). Most tested strains (n = 65/73 [91.5%]) and all other isolated strains (, , , and ) were susceptible to C/T. Most patients completed the treatment duration, including those with historical β-lactam hypersensitivity. Reasons for stopping treatment were planned EOT and improvement in condition; overall, 88.9% of patients (n = 56/63) experienced improvement in condition. No new safety signals were identified. Mean forced expiratory volume in 1 second improved from 1.33 L to 1.47 L before and after C/T treatment, respectively (n = 52; = .057).

Conclusions: C/T treatment was well tolerated and effective in pwCF, including those with previous β-lactam hypersensitivity.