2382. Ceftolozane/Tazobactam for the Treatment of Multidrug-Resistant Pseudomonas aeruginosa Infections in Immunocompromised Patients: A Multi-Center Study

Abstract

BackgroundCeftolozane/tazobactam (TOL-TAZ) is a novel cephalosporin antibiotic combined with a known β-lactamase inhibitor. It has activity against some extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and multidrug-resistant Pseudomonas aeruginosa (MDRPA). To date, little experience has been published on outcomes with TOL-TAZ for MDRPA infections in immunocompromised patients.MethodsThis was a retrospective study of adult patients (≥18 years) with an immunocompromising condition (solid-organ transplant; hematologic malignancy; solid tumors; metastatic cancer) at 20 academic medical centers who had microbiologically confirmed MDRPA isolated in culture and received TOL-TAZ for at least 24 hours. 30-day survival, in-hospital mortality, and the rates of microbiologic and clinical cure were assessed.ResultsCharacteristic Result (N = 65)Immunocompromising condition:Solid-organ transplantSolid tumorLeukemiaLymphoma/multiple myelomaMetastatic cancer n(%)35 (53.8)20 (30.7)4 (6.1)3 (4.6)3 (4.6)Male, n(%)38 (58.4)Age (median, IQR)64 (20–87)Charlson Comorbidity Index (median, IQR)6 (1–12)APACHE II score (median, IQR)20 (4–41)ICU, n(%)37(56.9)Hospital day index infection diagnosed (median, IQR)17 (0–265)Hospital day TOL-TAZ started (median, IQR)19 (0–284)3grs q8hrs, n(%)1.5grs q8hrs, n(%)23 (35.3)23 (35.3)Concomitant IV antibiotics, n(%)Aminoglycoside, n/N(%)Fluoroquinolone, n/N(%)Polymyxin, n/N(%)Β-lactam, n/N(%)15 (23.0)7/15 (46.7)4/15 (26.7)3/15 (20)1/15 (6.6)TOL-TAZ susceptible isolates, n/N (%)35/37 (94.6) Outcomes by primary infection Primary infectionn (%)30-day survival n/N(%)Microbiologic cure n/N(%)Clinical cure n/N(%)Pneumonia33 (50.7)30/33 (90.9)24/33 (72.7)28/33 (84.8)Wound/Bone/Joint12 (18.4)8/12 (66.6)7/12 (58.3)7/12 (58.3)UTI9 (13.8)7/9 (77.7)7/9 (77.7)8/9 (88.8)Intra-abdominal7 (10.7)7/7 (100)7/7 (100)4/7 (57.1)Bloodstream4 (6.1)4/4 (100)4/4 (100)4/4 (100) Overall outcomes, n(%)30-day survival56 (86.1)In-hospital mortality17 (26.1)Microbiologic cure49 (75.3)Clinical cure51(78.4)ConclusionIn this study of 65 critically-ill immunocompromised patients, the 30-day survival was 86.1%; clinical cure was78.4% and microbiologic cure 75.3%. TOL-TAZ is a viable option for immunocompromised patients with MDRPA infections.Disclosures J. Gallagher, Achaogen: Consultant, Consulting fee. Merck: Consultant, Grant Investigator and Speaker’s Bureau, Consulting fee and Research grant. Allergan: Consultant and Speaker’s Bureau, Consulting fee. Astellas: Consultant and Speaker’s Bureau, Consulting fee. Cempra: Consultant, Consulting fee. Cidara: Consultant, Consulting fee. CutisPharma: Consultant, Consulting fee. Paratek: Consultant, Consulting fee. Shionogi: Consultant, Consulting fee. Tetraphase: Consultant, Consulting fee. Theravance: Consultant, Consulting fee. The Medicines Company: Consultant, Consulting fee. Melinta: Speaker’s Bureau, Consulting fee.