Ultragenyx Pharmaceutical Inc.
Ultragenyx Pharmaceutical Inc., a biopharmaceutical company, focuses on the identification, acquisition, development, and commercialization of novel products for the treatment of rare and ultra-rare genetic diseases in North America, Latin America, Europe, the Middle East, Africa, and the Asia-Pacific. Its biologic products include Crysvita (burosumab), an antibody targeting fibroblast growth factor 23 for the treatment of X-linked hypophosphatemia, as well as tumor-induced osteomalacia; Mepsevii, an enzyme replacement therapy for the treatment of children and adults with Mucopolysaccharidosis VII; Dojolvi for the treatment of long-chain fatty acid oxidation disorders; and Evkeeza (evinacumab) for the treatment of homozygous familial hypercholesterolemia. The company's products candidates that are in Phase 3 clinical trials include UX143, a human monoclonal antibody for the treatment of osteogenesis imperfecta; UX111, an AAV9 gene therapy product candidate for the treatment of patients with Sanfilippo syndrome type A, or MPS IIIA, a rare lysosomal storage disease; DTX401, an adeno-associated virus 8 (AAV8) gene therapy clinical candidate for the treatment of patients with glycogen storage disease type Ia; DTX301, an AAV8 gene therapy for the treatment of patients with ornithine transcarbamylase; and GTX-102, an antisense oligonucleotide for the treatment of Angelman syndrome. It also develops UX701, an adeno-associated AAV9 gene therapy which is in Phase 2 clinical trial for the treatment of Wilson liver disease. The company has collaboration and license agreement with Kyowa Kirin Co., Ltd.; Saint Louis University; Baylor Research Institute; REGENXBIO Inc.; GeneTx; Mereo; University of Pennsylvania; Regeneron; and Abeona. Ultragenyx Pharmaceutical Inc. was incorporated in 2010 and is headquartered in Novato, California.
What does it do?
Ultragenyx makes medicines for rare genetic diseases — conditions so uncommon that most doctors will never see a single case in their career. Think of diseases like X-linked hypophosphatemia, which causes bones to soften and deform in children because the body can't process phosphate properly. Their drug Crysvita treats this by blocking a rogue protein that prevents the body from absorbing phosphate normally. These patients often have no other options, which makes Ultragenyx's work both medically critical and commercially interesting.
Rare disease drugs are one of the few areas in biotech where companies can charge very high prices with relatively little pushback, because the patient populations are small and the unmet need is enormous. Ultragenyx sits in a growing pipeline moment — it has approved drugs already generating revenue while simultaneously running trials that could add multiple new products. With gene therapy becoming a real commercial category, Ultragenyx is one of the few small-to-mid-sized biotechs with actual approved products AND a gene therapy pipeline, making it a meaningful name to watch.
How does it make money?
Ultragenyx makes money by selling its approved drugs directly to patients and healthcare systems, primarily through specialty pharmacies and hospital networks. Its biggest revenue driver is Crysvita, which brought in the majority of its roughly $700 million in 2024 revenue — though Ultragenyx shares some of those economics with its partner Kyowa Kirin depending on the territory. The company also earns from other approved products like Mepsevii and Dojolvi, plus milestone payments and royalties from licensing agreements. Revenue grew from about $600 million to $700 million year-over-year, which is solid, but the company is still burning cash — losing around $600 million net — because it's spending heavily on developing the next wave of drugs.
Why do investors care?
The bull case for Ultragenyx is that it's building a rare disease franchise at a time when its pipeline could deliver multiple new approvals in the next few years, including gene therapy candidates that could be one-time curative treatments — a major step up from lifelong drug dependency. If even one or two of its late-stage programs succeed, the revenue profile could look very different within three to five years. The company has already proven it can get drugs approved and commercialized, which removes a huge question mark that hangs over pure development-stage biotechs. The key thing that has to go right: clinical trial data needs to hold up and the FDA needs to stay cooperative.
Deep Dive
MemberA full investor briefing on Ultragenyx Pharmaceutical Inc. — history, leadership, risks, and outlook.