Objective: To assess the effects of recombinant human DNase (rhDNase) therapy on the cost of treating respiratory tract infections (RTIs) in patients with cystic fibrosis.
Design: We prospectively documented the use of healthcare services among 968 patients with cystic fibrosis who participated in a recent Phase III double-blind, multicenter, clinical trial in which patients were assigned randomly to receive either rhDNase 2.5 mg once daily, rhDNase 2.5 mg twice daily, or placebo. All patients were followed for 24 weeks. Data from secondary sources were used to estimate a total cost of RTI-related care (excluding the cost of study therapy) for each trial participant, based on observed levels of resource use.
Main outcome measures: Number of RTI-related hospital admissions, days of RTI-related outpatient antibiotic therapy (intravenous and oral), and total costs of RTI-related care (excluding the cost of study therapy).
Results: Patients randomized to receive rhDNase once daily averaged 0.15 fewer RTI-related hospital admissions (0.41 vs 0.56 for placebo; p < 0.05) and 1.5 fewer days of RTI-related outpatient intravenous antibiotic therapy (2.9 vs 4.4; p < 0.05). Patients randomized to receive rhDNase twice daily had 0.14 fewer hospital admissions (p < 0.01), but no reduction in outpatient intravenous antibiotic therapy. Compared with placebo, the cost of treating RTIs over 24 weeks was $814-1682 less among patients receiving rhDNase.
Conclusions: rhDNase therapy reduced the costs of treating RTIs in patients with cystic fibrosis; assuming once-daily dosing, these savings would offset about one-third of the cost of such therapy.