IONIS PHARMACEUTICALS INC

For three decades as a pioneer in RNA-targeted medicines, we have focused on bringing better futures to people with serious diseases. Today, we continue to drive innovation in RNA therapies. A deep understanding of disease biology and an industry-leading drug discovery technology propels our work, coupled with a passion and urgency to deliver better futures for patients.

We currently have five marketed medicines to treat serious diseases: SPINRAZA (nusinersen), QALSODY (tofersen), WAINUA (eplontersen), TEGSEDI (inotersen) and WAYLIVRA (volanesorsen). We also have a rich innovative late- and mid-stage pipeline in neurology, cardiology and other areas of high patient need. We currently have nine medicines in Phase 3 development and multiple additional medicines in early and mid-stage development.

We are using our multiple sources of revenue and our capital structure to continue investing in our commercial readiness efforts for multiple late-stage programs, our innovative pipeline and our technology. By continuing to focus on these priorities, we believe we are well positioned to drive future growth and to bring next-level value to patients and shareholders.

Marketed Medicines

SPINRAZA is an antisense medicine for the treatment of patients with spinal muscular atrophy, or SMA, a progressive, debilitating and often fatal genetic disease. Our partner, Biogen, is responsible for commercializing SPINRAZA worldwide. From inception through September 30, 2024, we have earned more than $2.2 billion in revenues from our SPINRAZA collaboration, including more than $1.8 billion in royalties on sales of SPINRAZA.

QALSODY is an antisense medicine that received accelerated approval from the United States, or U.S., Food and Drug Administration, or FDA, in April 2023 and marketing authorization under exceptional circumstances from the European Medicines Agency, or EMA, in May 2024 for the treatment of adult patients with superoxide dismutase 1 amyotrophic lateral sclerosis, or SOD1-ALS, a rare, neurodegenerative disorder that causes progressive loss of motor neurons leading to death. Our partner, Biogen, is responsible for commercializing QALSODY worldwide.

WAINUA (WAINZUA in Europe) is a once monthly, self-administered subcutaneous LIgand-Conjugated Antisense, or LICA, medicine that is approved in the U.S. and other countries for the treatment of adults with polyneuropathy of hereditary transthyretin-mediated amyloidosis, or ATTRv-PN, a debilitating, progressive, and fatal disease. In addition, WAINUA recently received a positive opinion supporting marketing authorization from the Committee for Medicinal Products for Human Use, or CHMP. WAINUA is the only approved medicine for the treatment of ATTRv-PN that can be self-administered via an auto-injector. We and AstraZeneca are commercializing WAINUA in the U.S. with the launch having commenced in January 2024. We and AstraZeneca are seeking regulatory approval for WAINUA in other parts of the world. AstraZeneca has exclusive rights to commercialize WAINUA outside of the U.S.

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TEGSEDI is a once weekly, self-administered subcutaneous medicine approved in the U.S., Europe, Canada and Brazil for the treatment of patients with ATTRv-PN. We currently sell TEGSEDI in Europe through our distribution agreement with Swedish Orphan Biovitrum AB, or Sobi. In October 2023, our agreement for TEGSEDI in North America was terminated and Sobi began transitioning responsibilities to us. Following the transition, we discontinued TEGSEDI in North America in 2024. In Latin America, PTC Therapeutics International Limited, or PTC, is commercializing TEGSEDI in Brazil and is pursuing access in additional Latin American countries through its exclusive license agreement with us.

WAYLIVRA is a once weekly, self-administered, subcutaneous medicine approved in Europe and Brazil as an adjunct to diet in adult patients with genetically confirmed familial chylomicronemia syndrome, or FCS, and at high risk for pancreatitis. We sell WAYLIVRA in Europe through our distribution agreement with Sobi. In Latin America, PTC is commercializing WAYLIVRA in Brazil for two indications, FCS and familial partial lipodystrophy, or FPL, and is pursuing access in additional Latin American countries through its exclusive license agreement with us.

Medicines in Registration and Phase 3 Studies

We currently have nine medicines in registration or Phase 3 studies for eleven indications, which are:

WAINUA (WAINZUA in Europe) is our medicine to treat patients with transthyretin amyloidosis, or ATTR, that is approved in the U.S., Canada and United Kingdom, or UK, for the treatment of adults with ATTRv-PN and is under regulatory review in other countries. The approval of WAINUA for ATTRv-PN was based on the positive results from the Phase 3 NEURO-TTRansform study showing that WAINUA halted disease progression and continuously improved quality of life at the 35-, 66- and 85-week analyses, which were published in the Journal of the American Medical Association, or JAMA. We launched WAINUA for the treatment of adults with ATTRv-PN in the U.S. in January 2024 and in Canada in October 2024 after securing a reimbursement program. In October 2024, WAINZUA was approved by the Medicines and Healthcare products Regulatory Agency, or MHRA, for the treatment of adults with ATTRv-PN in the UK with an accelerated National Institute for Health and Care Excellence, or NICE, recommendation. Additionally, in October 2024, WAINUA received a positive opinion supporting marketing authorization from CHMP. We are also developing WAINUA for ATTR cardiomyopathy, or ATTR-CM. We continue to progress our Phase 3 development program of WAINUA for ATTR-CM, with enrollment completed in the Phase 3 CARDIO-TTRansform study in July 2023 and data is expected in the second half of 2026. The FDA granted Fast Track designation to WAINUA for the treatment of patients with ATTR-CM in February 2024. Additionally, the FDA and EMA granted Orphan Drug designation to WAINUA for the treatment of ATTR in January 2022 and October 2023, respectively.

Olezarsen is our medicine in development for FCS, an ultra-rare indication, and severe hypertriglyceridemia, or sHTG, a much broader indication. Olezarsen is currently under Priority Review in the U.S. with a Prescription Drug User Fee Act, or PDUFA, action date of December 19, 2024 for FCS. Our regulatory submission was based on the positive results from the Phase 3 Balance study in patients with FCS showing statistically significant triglyceride lowering and a substantial reduction in acute pancreatitis events in addition to a favorable safety and tolerability profile that we reported in September 2023 and presented and published in the New England Journal of Medicine, or NEJM, in April 2024. We opened our Expanded Access Program for patients with FCS in the U.S. in April 2024. Olezarsen has been granted Breakthrough Therapy designation, Orphan Drug designation and Fast Track designation for the treatment of FCS by the FDA. We are currently conducting a broad Phase 3 development program for olezarsen for the treatment of sHTG including three Phase 3 studies supporting development (CORE, CORE2 and ESSENCE), which achieved full enrollment in 2024.

Donidalorsen is our medicine in development for the prophylactic treatment of hereditary angioedema, or HAE. Donidalorsen is currently under regulatory review in the U.S. with a PDUFA action date of August 21, 2025. Our regulatory submission was based on the positive results from our comprehensive Phase 2 and Phase 3 development program for donidalorsen. This included the Phase 3 OASIS-HAE study in patients treated every four weeks and every eight weeks that were simultaneously published in NEJM, and positive results from OASISplus, our trial that includes an open-label, or OLE, cohort for patients rolling over from the Phase 3 study and a separate cohort for patients who have transitioned to donidalorsen from other prophylactic HAE medications that we refer to as the “switch study.” In December 2023 and June 2024, we licensed commercialization rights for donidalorsen to Otsuka Pharmaceutical Co., Ltd., or Otsuka, in Europe and the Asia-Pacific region, respectively. Otsuka is preparing to submit a Marketing Authorization Application, or MAA, to the EMA. Donidalorsen was granted Orphan Drug designation by the FDA and EMA.

Zilganersen is our medicine in development for Alexander disease, or AxD. We completed enrollment in the Phase 3 portion of the ongoing study for patients with AxD in July 2024. Zilganersen was granted Fast Track designation for the treatment of AxD and Rare Pediatric designation by the FDA. Additionally, zilganersen was granted Orphan Drug designation by the FDA and EMA.

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Ulefnersen is our medicine in development for amyotrophic lateral sclerosis, or ALS, with mutations in the fused in sarcoma gene, or FUS. We are currently conducting a Phase 3 study of ulefnersen in juvenile and adult patients with FUS-ALS. Ulefnersen was granted Orphan Drug designation by the FDA and EMA.

QALSODY is our medicine to treat patients with SOD1-ALS that is marketed by Biogen. QALSODY was granted accelerated approval by the FDA in April 2023 and marketing authorization under exceptional circumstances by the EMA in May 2024 for patients with SOD1-ALS. Biogen is also evaluating QALSODY as a potential treatment for presymptomatic SOD1-ALS patients in the ongoing ATLAS study. QALSODY was granted Orphan Drug designation by the FDA and EMA.

Pelacarsen is our medicine in development to treat patients with elevated lipoprotein(a)-driven cardiovascular disease, or Lp(a)-driven CVD. Novartis is developing pelacarsen, including conducting the ongoing Lp(a) HORIZON Phase 3 cardiovascular outcome study in patients with elevated Lp(a)-driven CVD, which achieved full enrollment in July 2022 with more than 8,000 patients. Pelacarsen was granted Fast Track designation by the FDA.

Bepirovirsen is our medicine in development for chronic hepatitis B virus, or HBV. GSK is developing bepirovirsen, including conducting the ongoing B-Well Phase 3 program in patients with HBV, which achieved full enrollment in June 2024. GSK reported positive results from Phase 2 studies in 2023, including durable response data from the Phase 2 B-Sure long-term follow-up study of bepirovirsen in complete responder patients from the Phase 2b B-Clear study of patients with HBV. The FDA granted Fast Track designation and the Japanese Ministry of Health, Labour and Welfare granted SENKU designation to bepirovirsen for the treatment of patients with HBV.

IONIS-FB-LRx is our medicine in development for immunoglobulin A, or IgA, nephropathy, or IgAN. In the second quarter of 2023, Roche advanced IONIS-FB-LRx into Phase 3 development in patients with IgAN based on interim Phase 2 data. In October 2024, we reported positive data from the Phase 2 study of IONIS-FB-LRx in patients with IgAN.