PSY58 - An Observational Study of Ivacaftor in Patients with Cystic Fibrosis and Selected Non-G551D Gating Mutations in UK, Italy and Netherlands: Healthcare Resource Utilization from the First Interim Analysis of the Vocal Study

Abstract

The efficacy of ivacaftor in cystic fibrosis (CF) patients with non-G551D gating mutations was demonstrated in a Phase 3 randomized-controlled trial (KONNECTION). An observational study (VOCAL) is ongoing to evaluate real world outcomes of ivacaftor in the non-G551D gating population; this interim analysis describes healthcare resource utilization (HCRU) over 12 months from the VOCAL study. VOCAL is a Phase 4, multi-center, multinational observational study of patients with CF on ivacaftor in UK, Italy and Netherlands, aged ≥6 years, with one non-G551D gating mutation. VOCAL has 4 years of planned prospective data collection from time of enrollment. In the current interim analysis, HCRU including hospitalizations and antibiotic use were evaluated as exploratory endpoints for 12 months before and 12 months after ivacaftor initiation using a negative binomial model. 71 of 73 enrolled patients completed 12 months of treatment. 25 (34%) were male. Mean (SD) age was 26.9 (13.5) years, with 23 (32%) <18 years old. All-cause hospitalizations per patient year (PPY) showed a significant reduction from 0.44 pre-IVA to 0.17 post-IVA (rate ratio (RR) 0.38; 95% CI 0.15, 0.94); corresponding hospitalization days significantly reduced from 5.4 days PPY pre-IVA to 2.0 days post-IVA (RR 0.37; 95% CI 0.17, 0.84). Pulmonary exacerbations (PEx) requiring hospitalization significantly reduced from 0.33 PPY pre-IVA to 0.07 post-IVA (RR 0.21; 95% CI 0.08, 0.54). PEx-related antibiotic use showed significant reduction from 1.28 courses PPY pre-IVA to 0.29 courses post-IVA (RR 0.23; 95% CI 0.12, 0.44); corresponding antibiotic use days significantly reduced from 15.2 PPY pre-IVA to 3.4 post-IVA (RR 0.23; 95% CI 0.11, 0.48). This study demonstrates the significant impact of ivacaftor on HCRU including hospitalizations and antibiotic use in CF patients with non-G551D gating mutations, following initiation of ivacaftor treatment in a real-world setting.