Ultragenyx reported that its gene therapy candidate met a key primary endpoint in a Phase 3 trial for ornithine transcarbamylase (OTC) deficiency, a rare urea cycle disorder. The company disclosed the result from the 37‑patient study, marking a pivotal clinical milestone for a monoallelic metabolic condition with high unmet need. The result strengthens Ultragenyx’s late‑stage portfolio in rare metabolic diseases and positions the program for regulatory discussions. The data will determine next regulatory and commercialization strategy, including filing timing and potential labeling scope. Investors and partners will watch safety, durability, and the second primary endpoint readout closely before projecting commercial impact.