Outpatient intravenous antibiotic therapy compared with oral linezolid in patients with skin and soft tissue infections: A pharmacoeconomic analysis

Background: In patients with skin or soft tissue infections that do not require hospitalization, the choice between oral therapy and outpatient parenteral antimicrobial therapy (OPAT) depends on several factors. Oral linezolid is an effective antibiotic for skin or soft tissue infections and may be a suitable alternative to OPAT in this patient population. Objective: The aim of the study was to analyze the potential cost-effectiveness of oral linezolid compared with OPAT in adult patients with moderately severe skin or soft tissue infections referred to a hospital-based infusion center. Methods: Twenty patients with skin or soft tissue infections referred to an infusion center for OPAT were enrolled into a prospective, randomized, pilot clinical trial comparing OPAT to oral linezolid. Patients received their prescribed intravenous antibiotic (normal care group) or oral linezolid (600 mg every 12 hours) for a duration decided by their primary or emergency department physician and followed up for 4 weeks. Outcome measures recorded for the economic analysis included all clinic, emergency department, wound care, and infusion center visits as well as hospitalizations. Any additional medical care, including the number of doses of all antibiotics, was documented for each subject. The costs of care were standardized using Medicare reimbursement payments. Results: Most infections in each group involved cellulitis of the abdomen or the lower extremities. In the 10 patients who received OPAT, 2 received no additional antibiotics, 4 received additional oral therapy, and 4 were subsequently hospitalized due to lack of improvement. In the 10 patients who received linezolid, 9 were cured and 1 patient received additional oral antibiotics. None of these patients were hospitalized, but 3 received outpatient wound care. The costs for care in this pilot study, based on Medicare reimbursement payments, would average $1855 in the OPAT group compared with $1038 in patients who received oral linezolid. Conclusions: Oral linezolid can be a cost-effective alternative to OPAT in patients with skin or soft tissue infections, but its use could shift a significant amount of cost for care to the patient.