Week 52 COACH Trial Topline Results Confirm Consistent and Durable Treatment Benefits in Children with Achondroplasia (ACH)

Core Insights - Ascendis Pharma announced positive topline results from the Week 52 of the COACH trial, demonstrating that the combination therapy of once-weekly TransCon CNP and TransCon hGH showed durable growth without compromising safety or tolerability [2][3] Group 1: Trial Results - The combination therapy resulted in an annualized growth velocity (AGV) that exceeded the 97th percentile of average stature children [11] - For the treatment-naïve cohort, the mean AGV was 8.80 cm/year, with a mean ACH height Z-score improvement of +1.02, indicating a tripling of efficacy compared to TransCon CNP monotherapy [5][6] - The treated cohort showed a mean AGV of 8.42 cm/year, with an increase from baseline of 3.28 cm/year and a mean ACH height Z-score improvement of +0.86, increasing from 1.28 to 2.15 over 52 weeks [5][6] Group 2: Safety and Tolerability - The combination therapy was generally well tolerated, with mild treatment-emergent adverse events (TEAEs) consistent with those observed for the monotherapies [2][11] - Safety and tolerability profiles were consistent with TransCon CNP and TransCon hGH monotherapies, indicating a low incidence of injection site reactions [11] Group 3: Implications for Treatment - The results suggest that TransCon CNP may become a foundational therapy for achondroplasia, with TransCon hGH providing complementary benefits [2][3] - The trial highlights the potential for dual-agent regimens to set new standards of care in treating achondroplasia and other growth disorders [3][11] - Improvements in body proportionality and arm span were observed, aligning with the increase in linear growth, indicating benefits beyond just height [2][11] Group 4: Future Developments - Ascendis Pharma has submitted a protocol for a Phase 3 trial of TransCon CNP and TransCon hGH in pediatric achondroplasia and held an end of Phase 2 meeting with the FDA [7][11] - The U.S. FDA has granted Priority Review for TransCon CNP, with a PDUFA target action date of February 28, 2026 [3][11]