Ultragenyx Pharmaceutical Inc. (RARE) just got some very good news from the FDA, and investors are celebrating. The company's gene therapy, Genglycos (pariglasgene brecaparvovec-opnr, or DTX401), received accelerated approval from the U.S. Food and Drug Administration, sending shares up 11.28% to $29.20 in Thursday's premarket session.
This is a big deal for a few reasons. First, Genglycos is the first-ever FDA-approved treatment for Glycogen Storage Disease Type Ia (GSDIa), an ultra-rare genetic metabolic disorder. It's also Ultragenyx's first gene therapy to win approval, and its fifth FDA approval overall. Not bad for a company that's been pushing the envelope in rare disease treatments.
So, what exactly is GSDIa? It's a condition caused by a deficiency in the enzyme that helps the liver release glucose into the bloodstream. Without that enzyme, the liver struggles to control blood sugar levels, leading to potentially life-threatening episodes of hypoglycemia and other serious complications. The disorder is truly rare, affecting only 1,500 to 2,500 patients in the U.S. and 6,000 to 8,000 worldwide.
The approval is based on data from the 48-week Phase 3 GlucoGene study, which involved 46 participants aged eight and older. Those treated with DTX401 (at a dose of 1.0 x 10^13 GC/kg) showed a reduction in their cornstarch requirements compared to the placebo group. Cornstarch is a common dietary intervention for GSDIa patients to maintain glucose levels, so reducing that need is a meaningful outcome.
As part of the accelerated approval, Ultragenyx has committed to providing two years of safety and efficacy data from open-label commercial treatment of 50 patients and 20 control patients through its existing GSDIa Disease Monitoring Program (DMP). The DMP will also track previously treated clinical trial participants and these new commercial patients for a total of 10 years. That's a long-term commitment to ensuring the therapy works as intended.
Analysts are already weighing in. William Blair's Sami Corwin, who resumed coverage of Ultragenyx with an Outperform rating, noted that the wholesale acquisition cost for Genglycos will be $2.7 million per patient. That's a hefty price tag, but for a one-time gene therapy that could potentially offer lasting benefits, it might be justified. Corwin models $362 million in peak sales for Genglycos, which suggests significant commercial potential despite the small patient population.
"We are encouraged by the approval of Genglycos, which we believe is incrementally positive to Ultragenyx's stock," Corwin said in a note.
For Ultragenyx, this approval is a major milestone that could reshape its trajectory. Gene therapies are complex and expensive to develop, but they also offer the potential for transformative treatments. With Genglycos now on the market, Ultragenyx has a new revenue stream and a proof point for its gene therapy platform. Investors seem to agree, at least for now, as the stock is climbing in premarket trading.
Of course, the real test will be how well Genglycos performs in the real world. The accelerated approval pathway means more data is coming, and the company will need to confirm the therapy's benefits over time. But for patients with GSDIa, this approval is nothing short of life-changing. For Ultragenyx, it's a chance to solidify its position in the rare disease space.
