Ascendis Pharma Releases New Data on TransCon CNP, Showing Significant Improvements
Ascendis Pharma announced new data demonstrating TransCon hGH accelerated TransCon CNP's benefits beyond linear growth with substantial improvements in arm span, spinal canal dimensions, and lower limb alignment. The new data are from Week 52 of the ongoing Phase 2 COACH Trial of combination therapy with once-weekly TransCon CNP and once-weekly TransCon hGH in children with achondroplasia. Ascendis previously reported Week 52 COACH results that demonstrated mean annualized growth velocity exceeding the 97th-percentile of average stature children, without compromising safety or tolerability and with no acceleration of bone age. Unprecedented improvements in arm span observed at Week 52 with TransCon CNP and TransCon hGH combination therapy, a measure highly meaningful to the achondroplasia community, with the mean change from baseline in achondroplasia-specific arm span Z-scores at Week 52 for TransCon CNP treatment-naive and TransCon CNP-treated children in COACH were +1.02 and +0.66, respectively. The TransCon CNP treatment-naive cohort improved +9.4 cm and the TransCon CNP-treated cohort improved +7.9 cm. By comparison, humeral gain by limb lengthening surgery is approximately 8 cm per arm and carries a high complication risk. Mean of L1-L5 average changes in interpedicular distance for TransCon CNP treatment-naive and TransCon CNP-treated children on combination therapy in COACH were +1.7 mm and +1.1 mm, respectively, compared to +0.6 mm for children on TransCon CNP monotherapy in ApproaCH. Improvements in IPD offer the potential to reduce nerve compression and pain that can result from a narrowed spinal column. For the TransCon CNP treatment-naive cohort, the mean change in tibial femoral angle Z-score was -0.86 with combination therapy at Week 52 in COACH and was -0.47 for TransCon CNP monotherapy at Week 52 in ApproaCH, indicating enhanced straightening of the legs. Children previously treated with long-term TransCon CNP monotherapy for an average of 2.56 years maintained in normal range for TFA Z-score. For the TransCon CNP treatment-naive cohort, the mean change in TFA was -3.0 degrees with combination therapy in COACH and was -1.3 degrees for children on TransCon CNP monotherapy at Week 52 in ApproaCH. Children previously treated with long-term TransCon CNP monotherapy for an average of 2.56 years maintained TFA treatment benefit in the setting of accelerated growth. All children completed 52 weeks of treatment and remain on therapy in COACH. TransCon CNP is a prodrug of C-type natriuretic peptide administered once weekly, providing continuous exposure of active CNP to receptors on tissues throughout the body, including growth plates and skeletal muscle. TransCon hGH is a prodrug of somatropin administered once weekly, providing sustained release of active, unmodified somatropin. TransCon CNP was approved under the trade name Yuviwel by the FDA in February and is under review by the European Medicines Agency as a monotherapy for children with achondroplasia.
