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# Clinical Hold Lifted on Angelman Syndrome Study
- URL: https://www.fdaweb.com/clinical-hold-lifted-on-angelman-syndrome-study/
- Published: 2021-09-27T12:00:00.000Z
- Updated: 2026-09-14T17:16:14.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5150230

FDA has removed a clinical hold against a GeneTx Biotherapeutics and Ultragenyx Pharmaceutical clinical trial of GTX-102, an investigational treatment for Angelman syndrome. The companies are now permitted to begin dosing naive patients in a Phase 1/2 study in the U.S. in pediatric patients with Angelman syndrome. GeneTx previously received clearance, under a separate amendment, to begin the study in the United Kingdom and Canada. “The Phase 1/2 open-label, multiple-dose study evaluates the safety, tolerability, and plasma and cerebrospinal fluid concentrations of GTX-102 in pediatric patients with Angelman syndrome with a genetically confirmed diagnosis of full maternal *UBE3A* gene deletion,” the companies say.

Angelman syndrome is a rare, neurogenetic disorder caused by loss-of-function of the maternally inherited allele of the *UBE3A* gene, according to the companies. Those with the syndrome have developmental delay, balance issues, motor impairment, and debilitating seizures.