RARE Stock: Insider Activity, Filings & Research

Ultragenyx Pharmaceutical Inc. (RARE) — Drillr’s hub for RARE insider activity, SEC filings, earnings signals and AI research. Over the trailing 3 months, RARE insiders filed 0 open-market buys and 7 sales (SEC Form 4).

Sentiment

0/100

Buys (3m)

Sells (3m)

Net (3m)

-$686.5K

Insider trades by month Buys Sells

Jan

Feb

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Jun

Context3-month price +2.8%Institutions accumulating (13F)

Date	Insider	Type	Shares	Price
Jun 1, 2026	Horn Howardofficer: Chief Financial Officer	Sell	4,653	$23.77
May 18, 2026	Dunsire Deborahdirector	Grant	7,751	—
May 18, 2026	Fust Matthew Kdirector	Grant	7,751	—
May 18, 2026	Ray Amritdirector	Grant	7,751	—
May 18, 2026	Sanders Corazon (Corsee) D.director	Grant	7,751	—
May 18, 2026	SULIMAN SHEHNAAZdirector	Grant	7,751	—
May 18, 2026	SULIMAN SHEHNAAZdirector	Grant	14,058	$25.80
May 18, 2026	NARACHI MICHAELdirector	Grant	14,058	$25.80
May 18, 2026	WELCH DANIEL Gdirector	Grant	14,058	$25.80
May 18, 2026	Sanders Corazon (Corsee) D.director	Grant	14,058	$25.80
May 18, 2026	NARACHI MICHAELdirector	Grant	7,751	—
May 18, 2026	Fust Matthew Kdirector	Grant	14,058	$25.80
May 18, 2026	Ray Amritdirector	Grant	14,058	$25.80
May 18, 2026	WELCH DANIEL Gdirector	Grant	7,751	—
May 18, 2026	Dunsire Deborahdirector	Grant	14,058	$25.80

Source: RARE SEC Form 4 filings, latest Jun 1, 2026. For informational purposes only — not investment advice.

Overview

Ultragenyx Pharmaceutical Inc. (NASDAQ:RARE) is a biopharmaceutical company founded in 2010 and headquartered in Novato, California. The company went public in January 2014 and has established itself as a leader in developing treatments for rare and ultra-rare genetic diseases. Ultragenyx focuses on identifying, acquiring, developing, and commercializing novel therapeutic products that address significant unmet medical needs in patient populations that often have no approved treatment options. The company operates globally across North America, Europe, Latin America, and other international markets, with a particular emphasis on both biological therapies and cutting-edge gene therapies.

Business

Ultragenyx operates in the rare disease pharmaceutical sector, specifically targeting genetic disorders that affect small patient populations but cause severe, life-threatening conditions. Rare diseases are defined as conditions affecting fewer than 200,000 people in the United States, and ultra-rare diseases typically affect fewer than 20,000 patients. These conditions often have no approved treatments, creating urgent medical needs for patients and families. The company's commercialized product portfolio includes four main therapeutic products. Crysvita (burosumab) is a monoclonal antibody that targets fibroblast growth factor 23 (FGF23) and treats X-linked hypophosphatemia, a genetic condition causing soft bones and short stature, as well as tumor-induced osteomalacia. Dojolvi is a medical food containing triheptanoin that treats long-chain fatty acid oxidation disorders, metabolic conditions where the body cannot properly break down certain fats for energy. Evkeeza (evinacumab) is a monoclonal antibody for homozygous familial hypercholesterolemia, an extremely rare genetic condition causing dangerously high cholesterol levels. Mepsevii is an enzyme replacement therapy for Mucopolysaccharidosis VII (MPS VII), a lysosomal storage disorder. Based on recent financial data, Crysvita represents approximately 73% of total revenue ($410 million of $560 million in 2024), making it the company's primary commercial driver. Dojolvi contributes about 16% ($88 million), while Evkeeza and Mepsevii each represent roughly 5-6% of revenues. The company's clinical pipeline focuses heavily on gene therapies and advanced biologics. Key development programs include DTX401 for glycogen storage disease type 1a, UX143 (setrusumab) for osteogenesis imperfecta (brittle bone disease), GTX-102 for Angelman syndrome (a neurodevelopmental disorder), and UX701 for Wilson disease (a copper metabolism disorder). These programs represent potential breakthrough treatments for conditions with limited or no therapeutic options.

Revenue model

Ultragenyx generates revenue through multiple streams within the rare disease pharmaceutical model. The company earns money primarily through direct product sales of its commercialized therapies to healthcare providers, hospitals, and specialty pharmacies. For Crysvita, Ultragenyx has a profit-sharing arrangement with Kyowa Kirin, receiving milestone payments and profit shares from different geographic territories. The company's customer base consists of specialized healthcare providers including pediatric endocrinologists, geneticists, metabolic disease specialists, and rare disease treatment centers. Patients typically require chronic, long-term treatment, creating recurring revenue streams. Reimbursement comes through various channels including private insurance, government healthcare programs, and national health systems in international markets. Pricing dynamics in rare diseases allow for premium pricing due to the severe unmet medical need, small patient populations, and lack of alternative treatments. Gene therapies can command particularly high prices, often ranging from $1-2 million per treatment, as indicated by management commentary regarding their GSDIa gene therapy program. Several factors influence the company's margins and profitability. Positive margin drivers include the premium pricing power in rare diseases, growing patient identification and diagnosis rates, international market expansion (particularly in Latin America), and the transition from clinical-stage to commercial-stage programs. Margin pressures come from high research and development costs for clinical trials, manufacturing complexity for biologics and gene therapies, regulatory compliance costs, and the need to maintain global commercial infrastructure across multiple rare disease markets. The company also faces reimbursement challenges in certain international markets and competition from emerging therapies in some indications.

Risks & safety

Ultragenyx presents a moderate margin of safety with mixed financial health indicators typical of a clinical-stage biotechnology company. **Cash Position and Burn:** - Cash and short-term investments: $127 million (Q1 2025) - Quarterly cash burn: Approximately $166-183 million based on operating cash flow and free cash flow - Current burn rate suggests roughly 2-3 quarters of cash runway at current spending levels **Debt and Solvency:** - Debt-to-equity ratio: 0.27 (relatively low debt burden) - Current ratio: 2.40 (adequate short-term liquidity) - Total liabilities: $1.16 billion vs. total assets: $1.31 billion **Valuation Metrics:** - Price-to-book ratio: 24.17 (elevated, reflecting growth expectations) - Enterprise value appears reasonable relative to revenue run-rate - Trading at significant discount to peak valuations **Other Considerations:** - Strong revenue growth trajectory (28% year-over-year in Q1 2025) - Multiple late-stage programs approaching potential commercialization - Established commercial infrastructure generating positive cash flows from existing products - Path to profitability targeted for 2027, which may require additional financing before achieving cash flow positive operations

Recent development

Over the past few years, Ultragenyx has executed a strategic transformation from a primarily clinical-stage company to a commercial-stage rare disease specialist with multiple revenue-generating products. The company has significantly expanded its geographic footprint, achieving strong growth in Latin American markets where Crysvita revenue reached over $110 million annually, and successfully launching products in Europe, Canada, and Japan. The company has made several strategic acquisitions and partnerships to strengthen its pipeline, including acquiring global rights to UX111 for Sanfilippo syndrome and exercising options to gain full control of GTX-102 for Angelman syndrome. These moves consolidated control over key late-stage programs that are now approaching potential commercialization. Manufacturing capabilities have been substantially enhanced with the completion of a dedicated gene therapy manufacturing facility in Bedford, Massachusetts, providing in-house production capacity for the company's growing gene therapy portfolio. This facility represents a critical infrastructure investment supporting multiple programs including DTX401, DTX301, and other gene therapy candidates. The clinical pipeline has advanced significantly with multiple programs reaching late-stage development. UX111 for Sanfilippo syndrome has completed Phase III studies and filed for regulatory approval, with a PDUFA action date of August 2025. DTX401 for glycogen storage disease type 1a is preparing for BLA submission in mid-2025. UX143 (setrusumab) for osteogenesis imperfecta received Breakthrough Therapy Designation and is conducting pivotal Phase III studies with interim analyses expected in 2025. The company has also initiated next-generation programs including GTX-102 for Angelman syndrome, which has moved into Phase III development, and UX701 for Wilson disease, representing expansion into additional rare genetic conditions with significant unmet medical needs.

RARE company profile · for informational purposes only — not investment advice.

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