Ultragenyx Receives FDA Agreement to Expand Trial in U.S.

Ultragenyx Pharmaceutical Inc. today announced that the U.S. Food and Drug Administration (FDA) has reviewed and agreed to a protocol amendment to the Phase 1/2 study of GTX-102 in pediatric patients with Angelman syndrome that enables the company to harmonize dose ranges in the U.S. with those being used in ex-U.S. cohorts of the study. Outside of the U.S., the Phase 1/2 study has been actively enrolling and dosing patients in the expansion cohorts to verify the GTX-102 dose and treatment regimen that will be used in the Phase 3 program.

“Agreement on the protocol amendment enables comparable dose ranges across all geographies and allows us to move forward rapidly to complete the study. We have begun working urgently to activate multiple study sites in the U.S. and plan to begin enrollment as quickly as possible,” said Scott Stromatt, M.D., SVP and chief medical officer of neurology clinical development at Ultragenyx. “We are eager to expand the study in the U.S. to build on the encouraging data, which demonstrate important clinical activity across multiple functional domains impacted by Angelman syndrome with an acceptable safety profile.”

To read the full press statement from Ultragenyx, click here.

To read questions and answers from the Ultragenyx team on what this announcement could mean for the community, click here for the GTX-102 Team community statement.