Ultragenyx Pharmaceutical : Corporate Presentation

Corporate Deck

May 19, 2021

Legal Warning

Cautionary note regarding forward-lookingstatements: This presentation contains forward-looking statements, including, but not limited to, statements regarding our expectations and projections regarding our future operating results and financial performance, anticipated cost or expense reductions, plans with respect to commercializing our product and product candidates, our translational research program, expectations regarding our manufacturing capabilities, the expected timing of release of additional data for our product candidates, plans to initiate additional studies for product candidates and timing and design of these studies, plans regarding ongoing studies for existing programs, our liquidity position as of the most recent fiscal quarter end, expectations regarding the adequacy of clinical data to support marketing applications and approvals of product candidates, our intent to file, and potential timing and success of, marketing applications and other regulatory approvals, expectations regarding timing of receiving potential approval of product candidates, expectations regarding prevalence of patients, future regulatory interactions, and the value to be generated by our pipeline. Such forward-looking statements involve substantial risks and uncertainties that could cause our clinical development programs, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, our reliance on our third party partner, Kyowa Kirin Co., Ltd., for the supply of Crysvita, the effects from the COVID-19 pandemic on our clinical trial activities, business and operating results, smaller than anticipated market opportunities for our products and product candidates, manufacturing risks, competition from other therapies or products, uncertainties related to insurance coverage and reimbursement status of our newly approved products, our evolving integrated commercial organization, the uncertainties inherent in the clinical drug development process, such as the regulatory approval process, the timing of our regulatory filings the uncertainties inherent in the clinical drug development process, including the potential for substantial delays and risk that earlier study results may not be predictive of future study results, and other matters that could affect sufficiency of existing cash, cash equivalents and short-term investments to fund operations, the availability or commercial potential of our product and product candidates, and our ability to integrate acquired businesses, which are more fully described in our most recent Form 10-Q or Form 10-K under the caption "Risk Factors" and elsewhere in such reports. Any forward-looking statements made by us reflect our current views with respect to future events or to our future financial performance and involve known and unknown risks, uncertainties, and other factors that may cause our actual results, performance, or achievements to be materially different from any future results, performance, or achievements expressed or implied by these forward-looking statements. Accordingly, our actual results may materially differ from our current expectations, estimates, and projections. Given these uncertainties, you should not place undue reliance on these forward-looking statements.

Any forward-looking statements made by us in this presentation speak only as of the date of this presentation and represent our estimates and assumptions only as of the date of this presentation. Except as required by law, we assume no obligation, and we disclaim any intent, to update these statements to reflect actual results.

This presentation concerns commercial products as well as discussion of investigational drugs that are under preclinical and/or clinical investigation and which have not yet been approved for marketing by the U.S. Food and Drug Administration (FDA). They are currently limited by Federal law to investigational use, and no representations are made as to their safety or effectiveness for the purposes for which they are being investigated.

Ultragenyx, Ultragenyx Pharmaceutical, Ultragenyx Gene Therapy, Mepsevii, Dojolvi and our logo are our trademarks. Any other trademarks appearing in these slides are

2the property of their respective holders.

Building an Exceptional Rare Disease Company with Value Drivers Across Commercial, Clinical, and Platforms

Commercial

Expansion

Clinical

Development

Catalysts

Gene Therapy Manufacturing

• Continued Crysvita growth
• Strong Dojolvi launch for LC-FAOD
• Initiate four pivotal studies (including three gene therapy)
• Data catalysts and study initiations
• HeLa PCL: High quality, commercial scale
• Supports larger indications with reduced COGS

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2017-2020: Completing Four Approvals and Launches

Refilling the pipeline through efficient business development

Pipeline Approvals

MPS VII		TIO	LC-FAOD
	XLH

2017		2018	2019	2020	2021+
Pipeline Build
OTC AAV8	GSDIa AAV8	Wilson AAV			GENE THERAPY
UX701		Duchenne
DTX301	DTX401	CDKL5 Def. AAV		UX810
			UX055
		GSD III mRNA/LNP	Angelman-ASO	NUCLEIC ACID
			UX053		GTX102
						Osteogenesis MAb
						Imperfecta
						UX143

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Three Therapeutic Areas Approaching $1 Billion of Product Revenue in the Next Five Years

COMMERCIAL CLINICAL

BONE ENDOCRINE		METABOLICS

Ph 3

Ph 3

Ph 2/3

	Ph
Ph 1/2	1/2/3

Setrusumab	UX053	UX701	DTX401	DTX301
for OI	for GSDIII	for Wilson	for GSDIa	for OTC

XLH	TIO		MPS VII	LC-FAOD

CNS / MUSCLE

Ph 1/2

GTX-102

for Angelman

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