Ultragenyx reported that its AAV‑based gene therapy achieved one of two co‑primary endpoints in a Phase III study for ornithine transcarbamylase (OTC) deficiency, a rare urea cycle disorder. The company said the result supports the therapy’s biological activity and moves the program closer to potential regulatory submissions for a disease with high unmet need. Ultragenyx highlighted the trial’s statistical success on ammonia control while noting a second endpoint remains pending; the company intends to present detailed data to regulators and the medical community. The readout strengthens Ultragenyx’s rare‑disease pipeline and could influence valuation and partnering discussions as the program advances toward potential approval.