Ultragenyx reports reductions in major clinical events sustained in UX007 trial
Ultragenyx Pharmaceutical announced topline data from an ongoing long-term extension study of UX007 in patients with long-chain fatty acid oxidation disorder, demonstrating sustained reductions in the duration and frequency of major clinical events and a long-term safety profile similar to what has previously been seen with UX007. A total of 75 patients are enrolled in the long-term safety and efficacy study including 24 patients who were previously enrolled in the company-sponsored Phase 2 study, 20 naive patients who had not previously been treated with UX007 and 31 patients from expanded access or investigator-sponsored studies. For the Phase 2 study and naive patients, retrospective medical chart data were collected allowing comparison of the annualized major clinical event and duration rates between pre-UX007 and UX007 treatment periods. Patients who previously completed the Phase 2 company-sponsored study and rolled over to the extension study have now received treatment for an additional 78 weeks. The median annualized major clinical event and duration rates during the extension treatment period were zero. Over the entire treatment period, patients had a 67 percent reduction in median annualized event rate and a 66 percent reduction in the median annualized duration rate. The safety profile observed in the long-term extension study was consistent with what has been previously observed with UX007. The most common treatment-related adverse events were diarrhea, vomiting, and abdominal pain. One patient discontinued due to a treatment-related adverse event. There were two deaths during the extension study, both deemed to be related to disease progression and not due to treatment with UX007. Ultragenyx is on track to submit the New Drug Application in mid-2019. The submission will include these data from this long-term efficacy and safety extension study in 75 patients, the Phase 2 study of UX007 in 29 patients, a retrospective medical record review of 20 original compassionate use patients, data from 70 patients treated through expanded access, and a randomized controlled investigator-sponsored study of 32 patients showing an effect of UX007 on cardiac function.