2748. Ceftolozane/tazobactam For the Treatment of Cystic Fibrosis Patients: Results from a French Prospective Cohort Study

BACKGROUND: The aim of this prospective multicentre, French observational study was to describe the conditions of Ceftolozane/Tazobactam (C/T) use in hospital settings, and outcomes. This sub-analysis focuses on the cystic fibrosis (CF) patients included in the overall cohort. METHODS: Adult patients suffering from CF having received at least one dose of C/T and followed up as per routine clinical practice until stop of C/T were included in this analysis. Additional data related to CF were collected. RESULTS: Between October 2018 and December 2019, 63 patients with CF were enrolled from 28 sites. Mean age was 33.6 years and 44.4% were males. 12 patients (19.0%) received a lung transplant, 46.0% had comorbidities with diabetes (34.9%) being the most frequent. Most patients (69.8%) had normal renal function, almost one-third (28.6%) were immunosuppressed. One-half of patients presented with class 2 mutation of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. None of the patients received CFTR modulators due to non-availability during the study period. About one-half of patients (52.4%) experienced intolerance/allergy to antibiotics; of these, 78.1% was associated with Ceftazidime. Microbiology results showed that Pseudomonas aeruginosa was the most predominant pathogen representing 89.9% (71/79) of the isolates. C/T showed a very high susceptibility rate of 91.5% across those strains (Table 1). C/T demonstrated higher susceptibility rates than other B-lactam agents (Table 2). Treatment duration until complete cure had a median of 15 days and occurred in 44.4% of patients. Treatment duration until partial cure or end of treatment was a median of 15 days and occurred in 46% of patients (Table 3). Only 2 patients experienced an adverse event leading to a discontinuation of treatment. Treatment with C/T had a positive impact on pulmonary function measured by FEV1 (Table 4) with a mean increase after treatment from 1.33L (range 0.5 - 4.1L) to 1.47L (range 0.6 - 4.6L). [Figure: see text] [Figure: see text] [Figure: see text] CONCLUSION: These results suggest that C/T is an effective and safe option for the treatment of CF patients with a potential positive impact on FEV1 when treating bacterial infections mainly caused by Pseudomonas aeruginosa. [Figure: see text] DISCLOSURES: Xavier Bourge, PharmD, Merck: Employe Brune Akrich, MD, MSD: Employee David Boutoille, MSD France: Board Member Isabelle Brassac, Scientist, MSD France: salary Carole Mackosso, n/a, MSD France: MSD employee Jean-François Timsit, MD, merck: Advisor/Consultant Bernard Castan, MD, ADVANZ: SPEAKER MODERATOR|BIOMERIEUX: SPEAKER MODERATOR|GILEAD: Advisor/Consultant|MSD France: Board Member|MSD France: SPEAKER MODERATOR|SANOFI: Advisor/Consultant|SHIONOGI: Advisor/Consultant Pierre-Regis Burgel, MD,PHD, ASTRA-ZENECA: Honoraria|BOEHRINGER INGELHEIM: Honoraria|CHIESI: Honoraria|GSK: Honoraria|INSMED: Honoraria|NOVARTIS: Honoraria|PFIZER: Honoraria|VERTEX: Grant/Research Support|ZAMBON: Honoraria