Ultragenyx（RARE.US）apazunersen治疗Angelman综合征三期Aspire研究未达主要及关键次要终点，盘后暴跌43%

Ultragenyx Pharmaceutical ( RARE ) on Wednesday reported results from the Phase 3 Aspire study for apazunersen (GTX-102) in Angelman syndrome. The study did not achieve the primary endpoint of change from Baseline in Bayley-4 cognitive raw score nor the key secondary endpoint of net response in the multidomain responder index, sending shares down 43% in aftermarket trading. The safety profile observed in Aspire was consistent with Phase 1/2, the company said. “Based on everything we observed in the robust Phase 1/2 clinical development program and long-term extension study, we are disappointed by the Aspire result,” said CEO Emil Kakkis . “Even more, we are disappointed for the global patient community who has invested so much in early-stage research, working to bring a first-ever treatment to their children.” In Aspire , the randomized groups were comparable at baseline and consistent with the patients studied in Phase 2. There were no differences between the treated and control groups that could support efficacy in the Bayley Cognition raw scores nor in the MDRI when looking at net response or mean changes of the individual five endpoints included in the MDRI. Ultragenyx Pharmaceutical ( RARE ) will evaluate the apazunersen program in light of this outcome and make a decision on its disposition. The company will also assess its planned operations to define and implement significant expense reductions, while supporting its growing commercial business.