Ionis Pharmaceuticals : 2023 Ionis Investor Day Presentation

Miles,

SMA Patient

Innovation Day

Discovering, Developing and Delivering Transformational Medicines

October 4, 2023 | Nasdaq: IONS

Forward-Looking Statements

This presentation includes forward-looking statements regarding our business, financial guidance and the therapeutic and commercial potential of QALSODYTM (tofersen), SPINRAZA® (nusinersen), TEGSEDI® (inotersen), WAYLIVRA® (volanesorsen), eplontersen, olezarsen, donidalorsen, ulefnersen, zilganersen, pelacarsen, bepirovirsen, IONIS-FB-LRx, Ionis' technologies, and Ionis' other products in development. Any statement describing Ionis' goals, expectations, financial or other projections, intentions or beliefs is a forward-looking statement and should be considered an at-risk statement. Such statements are subject to certain risks and uncertainties including but not limited to those related to our commercial products and the medicines in our pipeline, and particularly those inherent in the process of discovering, developing and commercializing medicines that are safe and effective for use as human therapeutics, and in the endeavor of building a business around such medicines. Ionis' forward-looking statements also involve assumptions that, if they never materialize or prove correct, could cause its results to differ materially from those expressed or implied by such forward-looking statements. Although Ionis' forward-looking statements reflect the good faith judgment of its management, these statements are based only on facts and factors currently known by Ionis. As a result, you are cautioned not to rely on these forward-looking statements. These and other risks concerning Ionis' programs are described in additional detail in Ionis' annual report on Form 10-K for the year ended December 31, 2022, and most recent Form 10-Q, which are on file with the SEC. Copies of these and other documents are available at www.ionispharma.com.

In this presentation, unless the context requires otherwise, "Ionis," "Company," "we," "our," and "us" refers to Ionis Pharmaceuticals and its subsidiaries.

Ionis Pharmaceuticals® is a registered trademark of Ionis Pharmaceuticals, Inc. Akcea Therapeutics® is a registered trademark of Akcea Therapeutics, Inc. TEGSEDI® is a trademark of Akcea Therapeutics, Inc. WAYLIVRA® is a registered trademark of Akcea Therapeutics, Inc. QALSODYTM is a trademark of Biogen. SPINRAZA® is a registered trademark of Biogen.

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Commitment to Responsibility Supports Value and Resiliency

PATIENTS

At the core of everything we do is

advancing medicines that transform lives

At Ionis, we work with integrity and purpose to discover, develop and deliver life

transforming medicines

for the people who depend on us

We believe operating responsibly

and sustainably builds value and resiliency for our company and stakeholders

Read our most recent report

COMMUNITIES

We are proud of the work we do to support our communities

ENVIRONMENT

We are committed to doing our part to support a sustainable planet

Committed to Impact

OUR PEOPLE

We offer a rewarding, diverse and inclusive environment that empowers our people to thrive

INNOVATION

We are science-centric and dedicated to the perseverance and rigor the scientific approach demands

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Ionis Leadership Here Today

Brett Monia, Ph.D.	Onaiza Cadoret	Eric Swayze, Ph.D.	Beth Hougen
Chief Executive Officer	Executive Vice President,	Executive Vice President,	Chief Financial Officer
	Chief Global Product Strategy	Research
	& Operations Officer

Wade Walke,	Sam Tsimikas,	Kenneth	Holly	Rachel
Ph.D.	M.D.	Newman, M.D.	Kordasiewicz, Ph.D.	Carnes
Senior Vice President,	Senior Vice President, Global	Senior Vice President,	Senior Vice President,	Senior Vice President,
Investor Relations	Cardiovascular Development	Clinical Development	Neurology	New Product Strategy

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Thought Leaders

Here Today

Henry N. Ginsberg, M.D.

Irving Professor of Medicine

and Past Director,

Irving Institute for Clinical and

Translational Research,

Columbia University

Raffi Tachdjian, M.D., MPH,

FAAAAI, FACAAI

Associate Clinical Professor of

Medicine and Pediatrics, UCLA

School of Medicine; Chief,

Division of Allergy and

Immunology, Providence St. John

Medical Center

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