Implementation and evaluation of a complex outpatient oral antimicrobial therapy program (COpAT) in Canada.

Objective: We describe the implementation, outcomes, and challenges of a complex outpatient oral antimicrobial therapy program (COpAT) in Canada to provide a framework for those interested in establishing such a program. Setting: Outpatient ambulatory clinic led by infectious diseases physicians, serving patients from a tertiary hospital and a small community hospital. Design: Retrospective observational study that evaluated the efficacy, safety, and cost savings of patients enrolled in the program from August 2023 to June 2024. Results: One hundred three patients were included, of which 84.4% achieved successful clinical outcomes. Mean age of the patients was 62 years and 30% had diabetes. The top three sources of infections were bone and joint, intra-abdominal, and skin-and-soft tissue. Mean duration of COpAT was 37 days. Seventy-five percent of patients required only a single agent, and amoxicillin/clavulanic acid was most commonly used. Twenty-two patients developed an adverse reaction, of which three required a change in therapy and one resolved with antibiotic dose reduction. No C. difficile infections or mortality were reported 30-days post COpAT discharge. Twelve patients were re-admitted to the hospital; 50% of the cases were unrelated to infections. Compared to outpatient intravenous therapy, the total cost savings from COpAT were estimated to be $255,000 Canadian dollars (CAD), which translated to an average cost savings of $2500 CAD per patient per year. Conclusion: We demonstrated favorable clinical and safety outcomes with our COpAT program and substantial cost savings using existing infrastructure. COpAT allows efficient use of healthcare resources including decongestion of hospitals.