A Trial of Pulmozyme Withdrawal on Exercise Tolerance in Cystic Fibrosis Subjects With Severe Lung Disease (TOPIC)

This was a multicenter, randomized, double-blind, placebo-controlled study of patients with severe, though stable, cystic fibrosis (CF) whose routine treatment included Pulmozyme. Patients were randomized to either continue Pulmozyme or have therapy withdrawn for 2 weeks (placebo group). Patients must have had stable CF symptoms without any change in therapy for 2 weeks prior to enrollment in order to participate.