RT Journal Article SR Electronic T1 Ceftolozane–tazobactam in an elastomeric infusion device for ambulatory care: an in vitro stability study JF European Journal of Hospital Pharmacy JO Eur J Hosp Pharm FD British Medical Journal Publishing Group SP e84 OP e86 DO 10.1136/ejhpharm-2019-002093 VO 27 IS e1 A1 Edward Raby A1 Saiyuri Naicker A1 Fekade Bruck Sime A1 Laurens Manning A1 Steven C Wallis A1 Saurabh Pandey A1 Jason A Roberts YR 2020 UL http://ejhp.bmj.com/content/27/e1/e84.abstract AB Objectives Published in vitro stability data for ceftolozane–tazobactam supports intermittent short duration infusions. This method of delivery is not feasible for many outpatient antimicrobial therapy services that provide only one or two visits per day. This study aimed to assess time, temperature and concentration-dependent stability of ceftolozane–tazobactam in an elastomeric infusion device for continuous infusion across clinically relevant ranges encountered in outpatient antimicrobial therapy.Methods Ceftolozane–tazobactam was prepared to achieve initial concentrations representing total daily doses for ‘renal’, ‘standard’ and ‘high’ dose schedules in elastomeric infusion devices with a volume of 240 mL. Infusion devices incubated at room and body temperature were serially sampled over 48 hours. Refrigerated infusion devices were sampled over 10 days. Concentrations of ceftolozane and tazobactam were separately quantified using a validated ultra-high performance liquid chromatography–photodiode array method.Results The greatest loss of ceftolozane occurred at 37°C, however, stability remained above 90% at 24 hours. Tazobactam was more stable than ceftolozane under these conditions. There was minimal loss at 4°C for either component over 7 days.Conclusions Ceftolozane-tazobactam is suitable for ambulatory care delivered as a continuous infusion via an elastomeric infusion device.