IONIS PHARMACEUTICALS INC

For three decades, we have invented medicines that bring better futures to people with serious diseases. As a pioneer in RNA-targeted medicines with a deep understanding of disease biology and an industry-leading drug discovery technology, we are driven to deliver innovative, life-changing advances for patients.

With two independent commercial launches now underway, we transitioned into a fully integrated commercial-stage biotechnology company. We currently have seven marketed medicines to treat serious diseases: TRYNGOLZA (olezarsen), DAWNZERA (donidalorsen), WAINUA (eplontersen), SPINRAZA (nusinersen), QALSODY (tofersen), TEGSEDI (inotersen) and WAYLIVRA (volanesorsen). In addition, we are positioned to independently launch two medicines, olezarsen for the treatment of severe hypertriglyceridemia, or sHTG, and zilganersen for Alexander disease, or AxD, in 2026, assuming regulatory approval. We also have a rich innovative pipeline across our focus areas of neurology, cardiometabolic diseases and select areas of high patient needs. We currently have three wholly owned medicines and six partnered medicines in Phase 3 development, including obudanersen for Angelman syndrome, or AS, which we advanced into a Phase 3 study in the second quarter of 2025. We also have additional medicines in early and mid-stage development.

Our multiple sources of revenue and strong financial foundation enable our continued investments to support ongoing and planned launches and to advance our wholly owned medicines in development. Our key recent achievements, combined with our independent and partnered product launches anticipated by the end of 2027, position us well to help millions of patients with serious diseases and deliver increasing product and royalty revenue.

Our Marketed Medicines

TRYNGOLZA is a once monthly, self-administered LIgand-Conjugated Antisense, or LICA, medicine approved in the United States, or U.S., as an adjunct to diet to reduce triglycerides in adults with familial chylomicronemia syndrome, or FCS. TRYNGOLZA is also approved in the European Union, or EU, Canada and the United Kingdom, or UK, as an adjunct to diet in adult patients for the treatment of genetically confirmed FCS. TRYNGOLZA is the first and only treatment approvedby the U.S. Food and Drug Administration, or FDA, that significantly and substantially reduces triglyceride levels in adults with FCS and provides a clinically meaningful reduction in acute pancreatitis, or AP, events. TRYNGOLZA is the first medicine we are commercializing independently in the U.S. Sobi has exclusive rights to commercialize TRYNGOLZA in countries outside of the U.S., Canada and China.

DAWNZERA is an RNA-targeted medicine approved in the U.S. for prophylaxis to prevent attacks ofhereditary angioedema, or HAE, in adult and pediatric patients 12 years of age and older. DAWNZERA is also approved in the EU for the routine prevention of recurrent attacks of HAE in the same age group. DAWNZERA 80mg is self-administered via subcutaneous autoinjector once every four or eight weeks. DAWNZERA is the first and only FDA-approved RNA-targeted prophylactic therapy for HAE. DAWNZERA has the potential to offer durable efficacy, a favorable safety and tolerability profile, and the longest available dosing interval. DAWNZERA is the second medicine we are commercializing independently in the U.S. We licensed commercialization rights for DAWNZERA in Europe and the Asia-Pacific region to Otsuka Pharmaceutical Co., Ltd., or Otsuka.

WAINUA (WAINZUA in Europe) is a once monthly, self-administered subcutaneous LICA medicine that is approved in numerous countries, including the U.S., EU, UK, Canada and China, for the treatment of adults with polyneuropathy of hereditary transthyretin-mediated amyloidosis, or ATTRv-PN, a debilitating, progressive, and fatal disease. In January 2024, we and AstraZeneca launched WAINUA in the U.S. for the treatment of adults with ATTRv-PN. The launch of WAINUA is underway in numerous countries, including the countries in the EU, following the approval by the European Commission, or EC, in March 2025. We and AstraZeneca are co-commercializing WAINUA in the U.S. AstraZeneca has exclusive rights to commercialize WAINUA outside of the U.S. From inception through March 31, 2026, we have earned more than $640 million in revenues from our WAINUA collaboration, including approximately $80 million in royalties on sales of WAINUA.

SPINRAZA is an antisense medicine for the treatment of patients with spinal muscular atrophy, or SMA, a progressive, debilitating and often fatal genetic disease. Higher dose SPINRAZA was approved and launched in the U.S. and EU for the treatment of SMA. Higher dose SPINRAZA is also approved in Japan. Our partner, Biogen, is responsible for commercializing SPINRAZA worldwide. From inception through March 31, 2026, we have earned more than $2.5 billion in revenues from our SPINRAZA collaboration, including more than $2.1 billion in royalties on sales of SPINRAZA.

QALSODY is an antisense medicine that received accelerated approval from the 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. QALSODY was the first treatment approved to target a genetic cause of ALS. Our partner, Biogen, is responsible for commercializing QALSODY worldwide. 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.

TEGSEDI is a once weekly, self-administered subcutaneous medicine approved in Europe 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 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 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.

Our Innovative Late-Stage Pipeline of Ionis-Owned Investigational Medicines

Olezarsen is our investigational medicine currently under regulatory review for sHTG, a second potential indication with a broad patient population. The FDA has granted Priority Review of olezarsen, with a Prescription Drug User Fee Act, or PDUFA, action date of June 30, 2026. In March 2026, the European Medicines Agency, or EMA, accepted an indication extension application for olezarsen for the treatment of adult patients with sHTG. The regulatory submissions were based on positive results from the pivotal Phase 3 CORE and CORE2 studies in sHTG, as well as data from the Phase 3 Essence study. In 2025, the positive results from these studies were presented and published inThe New England Journal of Medicine. Additionally, the FDA granted Breakthrough Therapy designation to olezarsen as an adjunct to diet to reduce triglyceride levels in adults with sHTG. We licensed commercialization rights for olezarsen in most countries outside of the U.S., Canada and China to Sobi.

Zilganersen is our investigational medicine for AxD. The FDA has granted Priority Review of zilganersen, with a PDUFA action date of September 22, 2026. The regulatory submission was based on the positive results from the Phase 3 portion of the pivotal study in children and adults with AxD. These results were presented at the Child Neurology Society Annual Meeting in October 2025 and the American Academy of Neurology Annual Meeting in April 2026. We established an expanded access program in the U.S. for eligible patients aged two and older living with AxD. Zilganersen has received Fast Track and Rare Pediatric Disease designations from the FDA and received Orphan Drug designation from both the FDA and the EMA.

Obudanersen is our medicine in development for AS. In June 2025, we initiated the Phase 3 study, REVEAL, which we designed to evaluate the efficacy and safety of obudanersen. In addition, we are continuing to conduct the open label Phase 1/2 study, HALOS, of obudanersen in patients with AS designed to assess the safety, tolerability and activity of multiple ascending doses of obudanersen administered intrathecally. In 2025, we presented positive 12- and 18-month long-term extension data from the HALOS study which supports continued development. The FDA and EMA granted Orphan Drug designation to obudanersen. Additionally, the FDA granted Breakthrough Therapy, Fast Track and Rare Pediatric designations to obudanersen.

Our Innovative Late-Stage Pipeline of Partnered Investigational Medicines

Bepirovirsen is our medicine in development for chronic hepatitis B, or CHB. GSK is developing bepirovirsen. In January 2026, we and GSK announced positive topline results from the B-Well 1 and B-Well 2 pivotal Phase 3 studies of bepirovirsen in patients with CHB. Bepirovirsen has been accepted for regulatory review in three markets – the EU, China and Japan. Additional submissions are planned. The FDA has granted Priority Review of bepirovirsen, with a PDUFA action date of October 26, 2026. The FDA, Center for Drug Evaluation, or CDE, of National Medical Products Administration, or NMPA, of China and Japanese Ministry of Health, Labour and Welfare, or MHLW, granted bepirovirsen Fast Track designation, Breakthrough Therapy designation and SENKU (formerly known as SAKIGAKE) designation, respectively, for the treatment of patients with CHB.

Eplontersen is our medicine in development to treat patients with transthyretin amyloidosis cardiomyopathy, or ATTR-CM. We completed enrollment in the Phase 3 CARDIO-TTRansform study in July 2023. The FDA granted Fast Track designation to eplontersen for the treatment of patients with ATTR-CM. Additionally, the FDA and EMA granted Orphan Drug designation to eplontersen for the treatment of ATTR.

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 Phase 3 Lp(a) HORIZON cardiovascular outcome study in patients with elevated Lp(a)-driven CVD, which achieved full enrollment in July 2022 with more than 8,000 patients. The study design and baseline characteristics of the Phase 3 Lp(a) HORIZON study were published in the American Heart Journal in April 2025. The FDA granted Fast Track designation and the Center for Drug Evaluation of China National Medical Products Administration granted Breakthrough Therapy designation to pelacarsen for the treatment of patients with elevated Lp(a) and established CVD.

Sefaxersen is our medicine in development for immunoglobulin A, or IgA, nephropathy, or IgAN. In the second quarter of 2023, Roche advanced sefaxersen into Phase 3 development in patients with IgAN based on interim Phase 2 data.

Tofersen is our medicine in development for presymptomatic SOD1-ALS. Biogen is evaluating tofersen for treatment of presymptomatic individuals who have aSOD1 genetic mutation.

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 FUSION study of ulefnersen in juvenile and adult patients with FUS-ALS. We licensed global commercialization rights for ulefnersen to Otsuka. The FDA and EMA granted Orphan Drug designation to ulefnersen. The FDA also granted Fast Track designation to ulefnersen.