Ultragenyx Shares Plummet After Angelman Syndrome Drug Trial Fails

Ultragenyx reported that its Phase 3 study for GTX-102, an experimental treatment for Angelman syndrome, failed to meet both primary and secondary endpoints. The company stated that "there were no differences between the treated and control groups that could support efficacy."

Following the announcement, shares of the biopharmaceutical company lost nearly half their value. The failure also triggered a decline in shares for Ionis Pharmaceuticals, which is developing a similar therapy. Analysts noted that the loss of the Angelman treatment, which had projected peak sales of $1.8 billion, significantly impacts the company's financial outlook compared to its other pipeline candidate, UX111 for Sanfilippo syndrome.

In response to the trial results, the company is evaluating the future of the GTX-102 program. Ultragenyx is now seeking significant expense reductions to prioritize its approved products and maintain its goal of reaching profitability by 2027.