OBJECTIVES : To assess the cost-effectiveness of ceftolozane/tazobactam plus metronidazole compared with 8 alternatives used in the empiric treatment of complicated intra-abdominal infections (cIAI) in Colombia.

METHODS : A decision analytic Monte Carlo simulation model was used for the comparison of treatment-related costs (drugs and hospitalization) and quality-adjusted life years (QALYs) of patients with cIAI empirically treated with ceftolozane/tazobactam + metronidazole and one of the following alternatives: cefepime + metronidazole, ciprofloxacin + metronidazole, doripenem, levofloxacin + metronidazole, meropenem, piperacillin/tazobactam, ceftazidime + metronidazole or imipenem/cilastatin. Bacterial susceptibility to the initial empiric therapy was chosen as the efficacy measurement and was obtained from Program to Assess Ceftolozane/Tazobactam Susceptibility (PACTS) database on Latin American patients infected with gram-negative pathogens. Local costs for Colombia were obtained from a combination of clinical experts and local official databases on drug and procedure prices. Cost-effectiveness threshold was assumed to be three times the per-capita gross domestic product of Colombia (US$ 17,948.00 in 2017).

RESULTS : Ceftolozane/Tazobactam was cost-effective compared with a majority of alternatives on the treatment of cIAI, with an Incremental Cost-Effectiveness Ratio (ICER) of US $296.17/QALY when compared with cefepime + metronidazole, US $1,230.02/QALY when compared with ceftazidime + metronidazole, US $83.82/QALY when compared with ciprofloxacin + metronidazole, US $6,897.39/QALY when compared with doripenem, US $10,348.08/QALY when compared with imipenem/cilastatin, US $990.89/QALY when compared with levofloxacin + metronidazole and US $1,101.63/QALY when compared with piperacillin/tazobactam. Ceftolozane/Tazobactam was dominated by meropenem (US $-14,890.14/QALY), however the difference in QALYs was small (-0.05 QALYs per patient). Sensitivity analysis that considered only patients with any P. aeruginosa infection showed that ceftolozane/tazobactam was cost-effective or dominant over all considered comparators.

CONCLUSIONS : Ceftolozane/Tazobactam + metronidazole may be a cost-effective alternative in the empiric treatment of patients with cIAI in Colombia. Sensitivity analyses showed more favorable results in patients with cIAI caused by P. aeruginosa