Switching Patients to Home-Based Subcutaneous Immunoglobulin: an Economic Evaluation of an Interprofessional Drug Therapy Management Program

Home-based subcutaneous immunoglobulin (SCIg) therapy is an alternative to hospital-based intravenous infusions (IVIg). However, SCIg requires patient training and long-term support to ensure proper adherence, optimal efficacy and safety. We evaluated if switching patients to home-based SCIg including an interprofessional drug therapy management program (physician, community pharmacist and nurse) would be cost-effective within the Swiss healthcare system. A 3-year cost-minimization analysis was performed from a societal perspective comparing monthly IVIg in an outpatient clinic and home-based weekly SCIg including an interprofessional program. Healthcare costs (immunoglobulin, professional time, infusion pump and disposables) were derived from administrative data. Transportation and productivity loss were estimated by expert opinion. The results were expressed in Swiss francs (CHF) and converted to Euros and US dollars (1 CHF = 0.92a,not sign, 1 CHF = $1.02; www.xe.com, 12/14/2015). Under base case assumptions, SCIg was estimated to cost 35,862 CHF (33,134a,not sign; $36,595) per patient during the first year and 30,309 CHF (28,004a,not sign; $30,929) in subsequent years versus 35,370 CHF (32,679a,not sign; $36,095) per year for IVIg. The total savings from switching to SCIg with the interprofessional program were 9630 CHF (8897a,not sign; $9828) per patient over 3 years. The results were relatively sensitive to the cost per gram of IgG, the cost of equipment and the annual number of infusions. Home-based SCIg including an interprofessional therapy management program may be an efficient alternative for patients. The program provides long-term support from self-administration training to the responsible use of therapy (proper adherence, optimal efficacy and safety). Over the short term, additional costs from purchasing equipment and the drug therapy management program were offset by avoiding hospital costs.