Ionis Pharmaceuticals (IONS) stock price is $44.38, up 3.35% on the day, as of Oct 19, 2026. It has a market cap of $7.34Bn, and is classified in the Biotechnology industry (Healthcare sector).
Enterprise Value
Margins
P/FCF
Key Stats
Market Cap7.34 Bn
P/E-13.00
P/S8.40
Div. Yield0.00
Revenue Growth (1y) (Qtr)-40.73
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About
Ionis Pharmaceuticals Inc is a biotechnology company focused on the discovery and development of RNA targeted medicines for serious diseases. The company leverages its proprietary antisense technology to design therapies that modify gene expression and address the root cause of genetic disorders. Over three decades Ionis has built a pipeline that includes both marketed products and investigational candidates across neurology cardiometabolic and rare disease areas. The firm…
Ionis Pharmaceuticals Inc is a biotechnology company focused on the discovery and development of RNA targeted medicines for serious diseases. The company leverages its proprietary antisense technology to design therapies that modify gene expression and address the root cause of genetic disorders. Over three decades Ionis has built a pipeline that includes both marketed products and investigational candidates across neurology cardiometabolic and rare disease areas. The firm is headquartered in Carlsbad California and operates primarily in the United States with expanding commercial presence in Europe and other international markets.
Ionis Pharmaceuticals Inc generates revenue primarily from the sale of its seven approved medicines and from royalties milestone payments and license fees earned through collaborations with larger pharmaceutical partners. The marketed products include TRYNGOLZA for familial chylomicronemia syndrome DAWNZERA for hereditary angioedema WAINUA for hereditary transthyretin mediated amyloid polyneuropathy SPINRAZA for spinal muscular atrophy QALSODY for SOD1 amyotrophic lateral sclerosis TEGSEDI for hereditary transthyretin amyloid polyneuropathy and WAYLIVRA for familial chylomicronemia syndrome. In addition the company receives income from co promotion agreements and from upfront and milestone payments tied to clinical development programs. Ionis also earns revenue from manufacturing services provided to partners for clinical trial and commercial supply. In 2025 Ionis reported total revenue of $944 million and ended the year with cash cash equivalents and short term investments of $2.7 billion.
Ionis Pharmaceuticals Inc holds a leading position in the RNA targeted therapeutic space due to its pioneering antisense platform and broad proprietary pipeline. The company competes with other biotechnology firms such as Alnylam Arrowhead Pharmaceuticals and Roche that develop RNA interference or antisense based treatments. Ionis differentiates itself through its extensive intellectual property portfolio its ability to partner with major pharmaceutical companies and its track record of bringing multiple medicines to market. These strengths enable the company to maintain a robust pipeline and to generate sustained royalty income from partnered products. Furthermore Ionis invests heavily in research and development to advance next generation chemistries that may improve durability and expand the range of tissue targets for its therapeutic molecules.
Ionis Pharmaceuticals Inc serves patients suffering from rare genetic disorders including familial chylomicronemia syndrome hereditary angioedema hereditary transthyretin amyloid polyneuropathy spinal muscular atrophy SOD1 amyotrophic lateral sclerosis and other neurodegenerative and cardiometabolic conditions. The company’s therapeutic products are prescribed by physicians and dispensed through specialty pharmacies and hospital channels. In addition Ionis derives revenue from collaborations with major pharmaceutical companies such as AstraZeneca Biogen GSK Novartis Ono Otsuka and Roche. The firm also works with patient advocacy groups and healthcare providers to raise disease awareness and improve access to its therapies in underserved communities.
Sector:HealthcareSector rationaleIonis Pharmaceuticals is a biotechnology company that discovers and develops RNA targeted medicines, such as SPINRAZA and TEGSEDI, for serious genetic diseases. Its revenue is derived from the sale of approved medicines, royalties, and license fees from pharmaceutical partners, all of which fall squarely within the Healthcare sector's biotechnology and pharmaceuticals industries.Industries:BiotechnologyBiotechnologyPrimaryIonis is a biotechnology company that develops RNA-targeted medicines using proprietary antisense technology to modify gene expression. Its revenue is derived from the sale of biologic-based products like SPINRAZA and QALSODY, as well as royalties and milestone payments from collaborations.Contract ManufacturingContract ManufacturingSecondaryThe company earns revenue from providing manufacturing services to partners for both clinical trial and commercial supply of their therapeutic molecules.Classified using BQ-MICSCIK: 0000874015
Bull & bear
Investment Thesis
▲ Bull case
Ionis Pharmaceuticals, Inc. is positioned to capture significant untapped value from ozarsen in severe hypertriglyceridemia (sHTG), where the company has raised peak sales estimates from over $2 billion to over $3 billion based on compelling phase 3 data showing 72% triglyceride reduction and 85% reduction in acute pancreatitis events, combined with strategic payer research supporting a $40,000 annual WAC price that aligns with 2027 contracting cycles, enabling accelerated access post-approval and laying the foundation for ozarsen to become the company's first wholly owned multibillion-dollar medicine as the new standard of care in a large market of greater than 3 million addressable patients, with early adoption expected to focus on high-risk subgroups such as those with triglycerides above 880 mg/dL or a history of pancreatitis, creating a clear pathway to sustained growth as awareness and real-world evidence expand the treatable population over time.
The neurology pipeline, particularly zilgarnirsen for Alexander disease, represents a de-risked near-term catalyst with FDA priority review and a September 22 PDUFA date, supported by pivotal data demonstrating clinically meaningful disease-modifying benefit in a devastating orphan condition with no approved therapies, and its commercialization will serve as a template for future rare neurology launches, leveraging Ionis' established expertise in engaging highly specialized HCP networks and patient advocacy groups, while the company's broader neurology portfolio continues to advance with multiple wholly owned assets in clinical development, creating a durable pipeline that reduces reliance on any single asset and positions Ionis as a leader in RNA-targeted therapeutics for high unmet need areas.
Partnered programs are generating substantial and recurring revenue streams that are underappreciated by the market, exemplified by the recently triggered $45 million milestone from salinersen and the potential for additional milestones across favoplersen, epiravirsen, pelacarsen, and other collaborations, with epiravirsen receiving Breakthrough Therapy designation and priority review from the FDA with an October 26 PDUFA date, and GSK preparing to present unprecedented functional cure rates of 19% in the overall CHB population and 26% in the ≤1000 IU/mL HBsAg subgroup at EASL, which could accelerate regulatory approval and launch timelines, creating a diversified base of royalty and milestone income that reduces financial volatility and supports continued investment in wholly owned launches without compromising balance sheet strength.
Ionis' financial trajectory is improving faster than anticipated, with Q1 2026 revenue up 87% year-over-year to $246 million driven by 42% commercial revenue growth from Trangolza and Donzara and substantial R&D revenue, leading to an upward revision of full-year 2026 guidance to $875–900 million in total revenue and a narrowed non-GAAP operating loss range of $425–475 million, reflecting improving operating leverage as the company redeploys resources from late-stage studies to pipeline assets fueling next-phase growth, while maintaining a cash balance of approximately $1.9 billion and targeting cash-flow breakeven by 2028, demonstrating that the company's prudent fiscal management enables strategic investments without jeopardizing financial stability, even as it advances multiple independent launches.
Ionis Pharmaceuticals, Inc. is positioned to capture significant untapped value from ozarsen in severe hypertriglyceridemia (sHTG), where the company has raised peak sales estimates from over $2 billion to over $3 billion based on compelling phase 3 data showing 72% triglyceride reduction and 85% reduction in acute pancreatitis events, combined with strategic payer research supporting a $40,000 annual WAC price that aligns with 2027 contracting cycles, enabling accelerated access post-approval and laying the foundation for ozarsen to become the company's first wholly owned multibillion-dollar medicine as the new standard of care in a large market of greater than 3 million addressable patients, with early adoption expected to focus on high-risk subgroups such as those with triglycerides above 880 mg/dL or a history of pancreatitis, creating a clear pathway to sustained growth as awareness and real-world evidence expand the treatable population over time.
The neurology pipeline, particularly zilgarnirsen for Alexander disease, represents a de-risked near-term catalyst with FDA priority review and a September 22 PDUFA date, supported by pivotal data demonstrating clinically meaningful disease-modifying benefit in a devastating orphan condition with no approved therapies, and its commercialization will serve as a template for future rare neurology launches, leveraging Ionis' established expertise in engaging highly specialized HCP networks and patient advocacy groups, while the company's broader neurology portfolio continues to advance with multiple wholly owned assets in clinical development, creating a durable pipeline that reduces reliance on any single asset and positions Ionis as a leader in RNA-targeted therapeutics for high unmet need areas.
Partnered programs are generating substantial and recurring revenue streams that are underappreciated by the market, exemplified by the recently triggered $45 million milestone from salinersen and the potential for additional milestones across favoplersen, epiravirsen, pelacarsen, and other collaborations, with epiravirsen receiving Breakthrough Therapy designation and priority review from the FDA with an October 26 PDUFA date, and GSK preparing to present unprecedented functional cure rates of 19% in the overall CHB population and 26% in the ≤1000 IU/mL HBsAg subgroup at EASL, which could accelerate regulatory approval and launch timelines, creating a diversified base of royalty and milestone income that reduces financial volatility and supports continued investment in wholly owned launches without compromising balance sheet strength.
Ionis' financial trajectory is improving faster than anticipated, with Q1 2026 revenue up 87% year-over-year to $246 million driven by 42% commercial revenue growth from Trangolza and Donzara and substantial R&D revenue, leading to an upward revision of full-year 2026 guidance to $875–900 million in total revenue and a narrowed non-GAAP operating loss range of $425–475 million, reflecting improving operating leverage as the company redeploys resources from late-stage studies to pipeline assets fueling next-phase growth, while maintaining a cash balance of approximately $1.9 billion and targeting cash-flow breakeven by 2028, demonstrating that the company's prudent fiscal management enables strategic investments without jeopardizing financial stability, even as it advances multiple independent launches.
Ionis Pharmaceuticals, Inc. faces significant near-term execution risks in the ozarsen launch for sHTG, as management acknowledged that payer access will be delayed due to the need for final label review before coverage decisions are made, with some payers reportedly waiting six to nine months post-approval to review new therapies, which could substantially slow uptake beyond the initial high-risk patient focus and undermine the company's expectation of steady second-half 2026 growth, particularly since the $100–110 million full-year Trangolza guidance already assumes a modest trajectory tied to educating HCPs on the label and getting patients into specialized centers, creating a scenario where any slower-than-anticipated adoption in the broader sHTG population could delay revenue ramp-up and challenge the validity of the increased $3 billion peak sales estimate, which relies on rapid penetration across a large patient base.
The commercial success of Donzara in the HAE market may be overestimated due to the entrenched nature of prophylactic therapy use, with over 75% of U.S. patients currently on established treatments, and while Ionis reports strong early traction and positive feedback on efficacy and convenience, the transition from legacy therapies will take time in a well-established switch market, and the company's guidance of $110–120 million in full-year 2026 Donzara sales assumes steady conversion from existing prophylactic, on-demand, and treatment-naive patients, yet any slower uptake due to physician inertia, reimbursement hurdles, or patient reluctance to switch could result in revenue falling short of projections, especially since the launch is still in early stages and the majority of patients are expected to remain on four-week dosing initially, limiting the immediate impact of the every-eight-week dosing option that drives long-term cost efficiency and adherence.
Despite positive news on bepirovirsen, the partnered hepatitis B program remains subject to significant regulatory and commercial uncertainty, as the 19% functional cure rate in the overall CHB population, while statistically significant, is still modest in absolute terms and may not be sufficient to disrupt a market dominated by lifelong nucleos(t)ide analogue therapy, with GSK anticipating first regulatory decisions only in Q3 2026 and launch preparations underway, meaning any near-term revenue contribution to Ionis from milestones or royalties is likely deferred, and the company's reliance on such partnered programs as a financial accelerator could be overstated if regulatory timelines slip or if pricing and access challenges limit net sales potential, thereby reducing the expected tiered royalties of 10–12% that are critical to offsetting R&D expenses.
Ionis' financial outlook, while improved, remains dependent on successfully executing multiple independent launches in 2026—ozarsen for sHTG and zilgarnirsen for Alexander disease—while simultaneously funding commercial expansion for Trangolza and Donzara, and any delay in FDA approvals, such as a potential complete response letter for zilgarnirsen despite priority review, or slower-than-expected payer adoption for ozarsen, could force the company to reallocate resources or incur additional expenses to sustain launch momentum, thereby increasing operating costs beyond the low-teens percentage guidance range and pressuring the path to cash-flow breakeven in 2028, particularly given that the $1.9 billion cash balance includes an escrow deposit used to repay 0% convertible notes due April 1, 2026, meaning the underlying operational cash generation may be weaker than the headline figure suggests, and the company's ability to invest in future growth while maintaining financial discipline could be tested if near-term commercial execution falters.
Ionis Pharmaceuticals, Inc. faces significant near-term execution risks in the ozarsen launch for sHTG, as management acknowledged that payer access will be delayed due to the need for final label review before coverage decisions are made, with some payers reportedly waiting six to nine months post-approval to review new therapies, which could substantially slow uptake beyond the initial high-risk patient focus and undermine the company's expectation of steady second-half 2026 growth, particularly since the $100–110 million full-year Trangolza guidance already assumes a modest trajectory tied to educating HCPs on the label and getting patients into specialized centers, creating a scenario where any slower-than-anticipated adoption in the broader sHTG population could delay revenue ramp-up and challenge the validity of the increased $3 billion peak sales estimate, which relies on rapid penetration across a large patient base.
The commercial success of Donzara in the HAE market may be overestimated due to the entrenched nature of prophylactic therapy use, with over 75% of U.S. patients currently on established treatments, and while Ionis reports strong early traction and positive feedback on efficacy and convenience, the transition from legacy therapies will take time in a well-established switch market, and the company's guidance of $110–120 million in full-year 2026 Donzara sales assumes steady conversion from existing prophylactic, on-demand, and treatment-naive patients, yet any slower uptake due to physician inertia, reimbursement hurdles, or patient reluctance to switch could result in revenue falling short of projections, especially since the launch is still in early stages and the majority of patients are expected to remain on four-week dosing initially, limiting the immediate impact of the every-eight-week dosing option that drives long-term cost efficiency and adherence.
Despite positive news on bepirovirsen, the partnered hepatitis B program remains subject to significant regulatory and commercial uncertainty, as the 19% functional cure rate in the overall CHB population, while statistically significant, is still modest in absolute terms and may not be sufficient to disrupt a market dominated by lifelong nucleos(t)ide analogue therapy, with GSK anticipating first regulatory decisions only in Q3 2026 and launch preparations underway, meaning any near-term revenue contribution to Ionis from milestones or royalties is likely deferred, and the company's reliance on such partnered programs as a financial accelerator could be overstated if regulatory timelines slip or if pricing and access challenges limit net sales potential, thereby reducing the expected tiered royalties of 10–12% that are critical to offsetting R&D expenses.
Ionis' financial outlook, while improved, remains dependent on successfully executing multiple independent launches in 2026—ozarsen for sHTG and zilgarnirsen for Alexander disease—while simultaneously funding commercial expansion for Trangolza and Donzara, and any delay in FDA approvals, such as a potential complete response letter for zilgarnirsen despite priority review, or slower-than-expected payer adoption for ozarsen, could force the company to reallocate resources or incur additional expenses to sustain launch momentum, thereby increasing operating costs beyond the low-teens percentage guidance range and pressuring the path to cash-flow breakeven in 2028, particularly given that the $1.9 billion cash balance includes an escrow deposit used to repay 0% convertible notes due April 1, 2026, meaning the underlying operational cash generation may be weaker than the headline figure suggests, and the company's ability to invest in future growth while maintaining financial discipline could be tested if near-term commercial execution falters.