Ultragenyx fails phase 3 Angelman test, plots ‘significant expense reductions’

Ultragenyx's phase 3 Aspire trial of apazunersen in Angelman syndrome missed its primary endpoint of change from baseline in Bayley-4 cognitive raw score and its secondary endpoint of net response on the Multidomain Responder Index. The company is reviewing the program's future and planning significant expense reductions. Shares fell 43% after hours; no trial figures were disclosed.