IONS US Equity☆

Item 1A. RISK FACTORS

Investing in our securities involves a high degree of risk. You should consider carefully the following information about the risks described below, together with the other information contained in this report and in our other public filings in evaluating our business. If any of the following risks actually occur, our business could be materially harmed, and our financial condition and results of operations could be materially and adversely affected. As a result, the trading price of our securities could decline, and you might lose all or part of your investment.

Risks Related to the COVID-19 Pandemic

Our business could be materially adversely affected by the effects of health epidemics. To date, we believe the impacts of the recent COVID-19 pandemic on our business are limited and manageable.

Our business could be materially adversely affected by health epidemics in regions where we or our partners are commercializing our medicines, have concentrations of clinical trial sites or other business operations, and could cause significant disruption in the operations of third-party manufacturers and contract research organizations upon whom we rely. For example, since December 2019, a novel strain of coronavirus, SARS-CoV-2, causing a disease referred to as COVID-19, has spread worldwide. In March 2020, the World Health Organization declared the COVID-19 outbreak a pandemic, or the COVID-19 Pandemic, and the U.S. government-imposed restrictions on travel between the U.S., Europe and certain other countries. In addition, the Governor of the State of California and the Governor of the Commonwealth of Massachusetts, the states in which our and Akcea’s offices are located, respectively, each declared a state of emergency related to the spread of COVID-19 and issued executive orders that directed residents to stay at home.

In response to these public health directives and orders, we implemented work-from-home policies for most of our employees globally and generally suspended business-related travel. Out of an abundance of caution and to protect the health and welfare of our employees, we continue to maintain work-from-home policies for most of our employees. We believe the effects of these work-from-home and travel policies have thus far had a limited impact on our business.

These public health directives and orders have also impacted our and our partners’ sales efforts. For example, some physician and hospital policies that have been put in place as a result of the COVID-19 Pandemic restrict in-person access by third parties, which has in some cases impacted our commercialization efforts for TEGSEDI and WAYLIVRA. Additionally, Biogen has reported that as a result of the COVID-19 Pandemic, SPINRAZA sales revenues have decreased in part because SPINRAZA doses have been delayed due, directly or indirectly, to the COVID-19 Pandemic, and that future SPINRAZA sales revenues may be adversely affected by continued dosing delays.These and similar, and perhaps more severe, disruptions in our or our partner’s commercial operations could materially impact our business, operating results and financial condition in the future.

Quarantines, shelter-in-place, executive and similar government orders, or the perception that such orders, shutdowns or other restrictions on the conduct of business operations could occur, could impact personnel at third-party manufacturing facilities in the U.S. and other countries, or the availability or cost of materials, which would disrupt our supply chain.

We have experienced impacts to our clinical trial operations due to the COVID-19 Pandemic; however, we believe such impacts are limited and manageable. Some examples of these impacts include:

The spread of COVID-19 has caused a broad impact globally. While the potential economic impact brought by, and the duration of, the COVID-19 Pandemic may be difficult to assess or predict, it could result in significant disruption of global financial markets, reducing our ability to access capital, which could in the future negatively affect our liquidity. In addition, a recession or market correction resulting from the spread of COVID-19 could materially affect our business and has and could continue to affect the value of our securities.

The global COVID-19 Pandemic continues to rapidly evolve. While we have not yet experienced material adverse effects to our business as a result of the COVID-19 Pandemic, the ultimate impact of the COVID-19 Pandemic or a similar health epidemic is highly uncertain and subject to change. As such, we do not yet know the full extent of delays or impacts on our business, our clinical trials, healthcare systems or the global economy as a whole. However, these effects could have a material impact on our operations, and we will continue to monitor the COVID-19 Pandemic closely.

Risks Related to the Commercialization of our Medicines

We have limited experience as a company in commercializing medicines, and we may have to invest significant resources to develop these capabilities. If we are unable to establish effective marketing, sales and distribution capabilities or enter into agreements with third parties to market, sell and distribute our medicines, we may not be able to generate revenue from our medicines.

We have limited experience as a company in the marketing, sale and distribution of pharmaceutical products and there are significant risks involved in building and managing a sales organization, including our ability to hire, retain and incentivize qualified individuals, generate sufficient sales leads, provide adequate training to sales and marketing personnel and effectively manage a geographically dispersed sales and marketing team. Any failure to effectively manage our internal sales, marketing and distribution capabilities would adversely impact the commercialization of our medicines. We may not be able to enter into collaborations or hire consultants or external service providers to assist us in sales, marketing and distribution functions on acceptable financial terms, or at all. Even if we are able to engage third parties to market, sell and distribute our medicines, our product revenues and profitability may be lower if we rely on such third parties for these functions than if we were to perform them on our own. In addition, we likely will have little control over such third parties, and any of them may fail to devote the necessary resources and attention to market, sell and distribute our medicines effectively. If we are not successful in commercializing our medicines, either on our own or through arrangements with one or more third parties, we may not be able to generate revenue from our medicines.

If the market does not accept our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development, we are not likely to generate substantial revenues or become consistently profitable.

Even if our medicines are authorized for marketing, including SPINRAZA, TEGSEDI and WAYLIVRA, our success will depend upon the medical community, patients and third-party payers accepting our medicines as medically useful, cost-effective, safe and convenient. Even when the FDA or foreign regulatory authorities authorize our or our partners’ medicines for commercialization, doctors may not prescribe our medicines to treat patients. We and our partners may not successfully commercialize additional medicines.

Additionally, in many of the markets where we or our partners may sell our medicines in the future, if we or our partners cannot agree with the government or other third-party payers regarding the price we can charge for our medicines, then we may not be able to sell our medicines in that market. Similarly, cost control initiatives by governments or third-party payers could decrease the price received for our medicines or increase patient coinsurance to a level that makes our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development, economically unviable.

The degree of market acceptance for our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development, depends upon a number of factors, including the:

● receipt and scope of marketing authorizations;

● cost and effectiveness of our medicines compared to other available therapies;

● patient convenience of the dosing regimen for our medicines; and

● reimbursement policies of government and third-party payers.

Based on the profile of our medicines, physicians, patients, patient advocates, payers or the medical community in general may not accept or use any medicines that we may develop.

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For example, the product label for TEGSEDI in the U.S. has a boxed warning for thrombocytopenia and glomerulonephritis, requires periodic blood and urine monitoring, and TEGSEDI is only available through a Risk Evaluation and Mitigation Strategy, or REMS, program. Our main competition in the U.S. market for TEGSEDI is patisiran, marketed by Alnylam Pharmaceuticals, Inc. Although patisiran requires intravenous administration and pre-treatment with steroids, it does not have a boxed warning or REMS. Additionally, the product label for WAYLIVRA in the EU requires regular blood monitoring. In each case, these label requirements could negatively affect our ability to attract and retain patients for these medicines. We believe that the enhanced monitoring we have implemented to support early detection and management of these issues can help manage these safety issues so that patients can continue treatment. Since implementation of the enhanced monitoring, serious platelet events have been infrequent. While we believe we can better maintain patients on TEGSEDI and WAYLIVRA through our patient-centric commercial approach where we plan to have greater involvement with physicians and patients, if we cannot effectively maintain patients on TEGSEDI or WAYLIVRA, including due to limitations or restrictions on our ability to conduct periodic blood and urine monitoring of our patients as a result of the current COVID-19 Pandemic, we may not be able to generate substantial revenue from TEGSEDI or WAYLIVRA sales.

If we or our partners fail to compete effectively, our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development, will not contribute significant revenues.

Our competitors engage in drug discovery throughout the world, are numerous, and include, among others, major pharmaceutical companies and specialized biopharmaceutical firms. Other companies are engaged in developing antisense technology. Our competitors may succeed in developing medicines that are:

● priced lower than our medicines;

● safer than our medicines;

● more effective than our medicines; or

● more convenient to use than our medicines.

These competitive developments could make our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development, obsolete or non-competitive.

Certain of our partners are pursuing other technologies or developing other medicines either on their own or in collaboration with others, including our competitors, to treat the same diseases our own collaborative programs target. Competition may negatively impact a partner’s focus on and commitment to our medicines and, as a result, could delay or otherwise negatively affect the commercialization of our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA.

Many of our competitors have substantially greater financial, technical and human resources than we do. In addition, many of these competitors have significantly greater experience than we do in conducting preclinical testing and human clinical studies of new pharmaceutical products, in obtaining FDA and other regulatory authorizations of such products and in commercializing such products. Accordingly, our competitors may succeed in obtaining regulatory authorization for products earlier than we do.

There are several pharmaceutical and biotechnology companies engaged in the development or commercialization in certain geographic markets of products against targets that are also targets of products in our development pipeline. For example:

● Onasemnogene abeparvovec and risdiplam compete with SPINRAZA;

● Patisiran, tafamidis and tafamidis meglumine compete with TEGSEDI;

● Vutrisiran and AG10 could compete with TEGSEDI and IONIS-TTR-LRx;

● Arimoclomol, ultomiris, mastinib and trehalose could compete with tofersen.

Specifically, SPINRAZA faces competition from onasemnogene abeparvovec, a new gene therapy product that was approved in the U.S. in May 2019 and in the EU in May 2020 for the treatment of SMA as well as risdiplam, a new oral product for the treatment of SMA that was approved in the U.S. in August 2020. Biogen has disclosed that SPINRAZA revenue has decreased due in part to lower sales volumes as a result of increased competition and that future sales of SPINRAZA may be adversely affected by the commercialization of competing products. SPINRAZA injection for intrathecal use is an antisense medicine indicated for the treatment of SMA patients of all ages approved in over 50 countries.

Additionally, companies that are developing medicines that target the same patient populations as our medicines in development may compete with us to enroll participants in the clinical trials for such medicines, which could make it more difficult for us to complete enrollment for these clinical trials.

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Certain of our medicines may compete with our other medicines, which could reduce our expected revenues.

Certain of our medicines inhibit the production of the same protein. For example, WAYLIVRA inhibits the production of the same protein as IONIS-APOCIII-LRx and TEGSEDI inhibits the production of the same protein as IONIS-TTR-LRx. We believe the enhancements we incorporated into IONIS-APOCIII-LRx and IONIS-TTR-LRx can provide greater patient convenience by allowing for significantly lower doses and less frequent administration compared to WAYLIVRA and TEGSEDI, respectively. As such, to the extent physicians and patients elect to use IONIS-APOCIII-LRx or IONIS-TTR-LRx instead of WAYLIVRA or TEGSEDI, respectively, it will reduce the revenue we derive from those medicines. In addition, while vupanorsen, IONIS-APOCIII-LRx and WAYLIVRA use different mechanisms of action, if vupanorsen and IONIS-APOCIII- LRx can effectively lower triglyceride levels in patients, including patients with FCS, WAYLIVRA, vupanorsen and IONIS-APOCIII-LRx may compete with each other.

Our medicines could be subject to regulatory limitations following approval.

Following approval of a medicine, we and our partners must comply with comprehensive government regulations regarding the manufacture, marketing and distribution of medicines. Promotional communications regarding prescription medicines must be consistent with the information in the product’s approved labeling. We or our partners may not obtain the labeling claims necessary or desirable to successfully commercialize our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development.

The FDA and foreign regulatory bodies have the authority to impose significant restrictions on an approved medicine through the product label and on advertising, promotional and distribution activities. For example:

● TEGSEDI requires periodic blood and urine monitoring;

● in the U.S., TEGSEDI is available only through a REMS program; and

Prescription medicines may be promoted only for the approved indications in accordance with the approved label. The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses, and a company that is found to have improperly promoted off-label may be subject to significant liability.

In addition, when approved, the FDA or a foreign regulatory authority may condition approval on the performance of post-approval clinical studies or patient monitoring, which could be time consuming and expensive. For example, in connection with the conditional marketing approval for WAYLIVRA in the EU, we are required to conduct a post-authorization safety study to evaluate the safety of WAYLIVRA on thrombocytopenia and bleeding in FCS patients taking WAYLIVRA. If the results of such post-marketing studies are not satisfactory, the FDA, EC or other foreign regulatory authority may withdraw marketing authorization or may condition continued marketing on commitments from us or our partners that may be expensive and time consuming to fulfill.

If we or others identify side effects after any of our medicines are on the market, or if manufacturing problems occur subsequent to regulatory approval, or if we, our manufacturers or our partners fail to comply with regulatory requirements, we or our partners may, among other things, lose regulatory approval and be forced to withdraw products from the market, need to conduct additional clinical studies, incur restrictions on the marketing, distribution or manufacturing of the product, and/or change the labeling of our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA.

We depend on our collaboration with Biogen for the development and commercialization of SPINRAZA.

We have entered into a collaborative arrangement with Biogen to develop and commercialize SPINRAZA. We entered into this collaboration primarily to:

● fund our development activities for SPINRAZA;

● seek and obtain regulatory approvals for SPINRAZA; and

● successfully commercialize SPINRAZA.

We are relying on Biogen to obtain additional regulatory approvals for SPINRAZA, manufacture and successfully commercialize SPINRAZA. In general, we cannot control the amount and timing of resources that Biogen devotes to our collaboration. If Biogen fails to further develop SPINRAZA, obtain additional regulatory approvals for SPINRAZA, manufacture or commercialize SPINRAZA, or if Biogen’s efforts are not effective, our business may be negatively affected.

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Our collaboration with Biogen may not continue for various reasons. Biogen can terminate our collaboration at any time. If Biogen stops developing or commercializing SPINRAZA, we would have to seek or spend additional funding, and SPINRAZA’s commercialization may be harmed or delayed.

Our collaboration with Biogen may not result in the continued successful commercialization of SPINRAZA. If Biogen does not continue to successfully commercialize SPINRAZA, we will receive limited revenues for SPINRAZA.

If we cannot optimize and maintain effective marketing and sales capabilities or enter into agreements with third parties to market and sell TEGSEDI and WAYLIVRA, we may not generate significant product revenue from TEGSEDI or WAYLIVRA.

To successfully commercialize TEGSEDI and WAYLIVRA, we must effectively manage our marketing, sales and distribution capabilities or make arrangements with third parties to perform these services. We may not be successful in doing so. To commercialize WAYLIVRA in the initial indications we are pursuing and to continue the commercialization of TEGSEDI, we will need to optimize and maintain specialty sales forces in the global regions where we currently market or expect to market TEGSEDI and WAYLIVRA, supported by case managers, reimbursement specialists, partnerships with specialty pharmacies, injection training, routine blood and urine monitoring and a medical affairs team.

Even though certain members of our management team and other employees have experience commercializing medicines, as a whole we have limited experience marketing, selling and distributing medicines, and there are significant risks involved in building, tailoring, optimizing and managing a commercial infrastructure. We expect the recent Akcea Acquisition will result in significant turnover that could impair our ability to manage Akcea’s business. If our efforts to integrate key Akcea employees into Ionis following the Akcea Acquisition are not successful, it could impair our ability to commercialize TEGSEDI and WAYLIVRA.

It is expensive and time consuming for us to maintain our own sales forces and related compliance protocols to market TEGSEDI and WAYLIVRA. We may never successfully optimize or manage this capability and any failure could harm the commercial launch of WAYLIVRA or adversely affect TEGSEDI sales. Additionally, we and our partners will have to compete with other companies to recruit, hire, train, manage and retain marketing and sales personnel.

We have incurred expenses launching,optimizing and managing the marketing and sales infrastructure for TEGSEDI in Europe, Canada and the U.S., and WAYLIVRA in Europe. If regulatory requirements or other factors cause the commercialization of TEGSEDI or WAYLIVRA to be less successful than expected in important markets, we would incur additional expenses for having invested in these capabilities prior to realizing any significant revenue from sales of TEGSEDI or WAYLIVRA. Our sales force and marketing teams may not successfully commercialize TEGSEDI or WAYLIVRA.

To the extent we decide to rely on third parties to commercialize TEGSEDI or WAYLIVRA in a particular geographic market, we will have less control over sales efforts and may receive less revenue than if we commercialized TEGSEDI or WAYLIVRA by ourselves. We have entered into agreements with third parties to commercialize our medicines as follows:

If Sobi or PTC does not successfully commercialize TEGSEDI or WAYLIVRA, including as a result of delays or disruption caused by the current COVID-19 Pandemic, we may receive limited revenue for TEGSEDI or WAYLIVRA in Europe, Latin America or certain Caribbean countries.

If we cannot effectively build and manage our distribution, medical affairs, market access, marketing and sales infrastructure, or find a suitable third party to perform such functions, the sales of TEGSEDI and WAYLIVRA may be adversely affected. Any such events may result in decreased sales and lower revenue, which could have a material adverse effect on our business, prospects, financial condition and results of operations.

In addition, in response to the public health directives and orders related to the COVID-19 Pandemic, we implemented work-from-home policies for our employees globally and suspended business-related travel. We believe the effects of the government orders and our work-from-home and travel policies in response to the COVID-19 Pandemic have thus far had a limited impact on our productivity, business and commercialization efforts for TEGSEDI and WAYLIVRA, but the effects of these orders and policies may become more significant in the future.

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Our operations are subject to additional healthcare laws.

Our operations are subject to additional healthcare laws, including federal and state anti-kickback laws, false claims laws, transparency laws, such as the federal Sunshine Act, and health information privacy and security laws. Efforts to ensure that our operations comply with applicable healthcare laws and regulations involve substantial costs. It is possible that governmental authorities will conclude that our business practices may not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. Penalties for violations of applicable healthcare laws and regulations may include significant civil, criminal and administrative penalties, damages, disgorgement, fines, imprisonment, exclusion of products from government funded healthcare programs, such as Medicare and Medicaid, and additional reporting requirements and oversight if we enter into a corporate integrity agreement or similar agreement to resolve allegations of non-compliance with these laws. In addition, violations may also result in reputational harm, diminished profits and future earnings.

If government or other third-party payers fail to provide adequate coverage and payment rates for our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development, our revenue will be limited.

In both domestic and foreign markets, sales of our current and future products will depend in part upon the availability of coverage and reimbursement from third-party payers. The majority of patients in the U.S. who would fit within our target patient populations for our medicines have their healthcare supported by a combination of Medicare coverage, other government health programs such as Medicaid, managed care providers, private health insurers and other organizations. Coverage decisions may depend upon clinical and economic standards that disfavor new medicines when more established or lower cost therapeutic alternatives are already available or subsequently become available. Assuming coverage is approved, the resulting reimbursement payment rates might not be enough to make our medicines affordable. Accordingly, SPINRAZA, TEGSEDI and WAYLIVRA for FCS in the EU and, if approved, WAYLIVRA in the U.S. or Canada and for additional indications, and our medicines in development, will face competition from other therapies and medicines for limited financial resources. We or our partners may need to conduct post-marketing studies to demonstrate the cost-effectiveness of any future products to satisfy third-party payers. These studies might require us to commit a significant amount of management time and financial and other resources. Third-party payers may never consider our future products as cost-effective. Adequate third-party coverage and reimbursement might not be available to enable us to maintain price levels sufficient to realize an appropriate return on investment in product development.

Third-party payers, whether foreign or domestic, or governmental or commercial, are developing increasingly sophisticated methods of controlling healthcare costs. In addition, in the U.S., no uniform policy of coverage and reimbursement for medicines exists among third-party payers. Therefore, coverage and reimbursement for medicines can differ significantly from payer to payer. For example, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act of 2010, or collectively, the Affordable Care Act, was passed in March 2010, and substantially changed the way healthcare is financed by both governmental and private insurers, and continues to significantly impact the U.S. pharmaceutical industry. There remain judicial and Congressional challenges to certain aspects of the Affordable Care Act, as well as efforts to repeal or replace certain aspects of the Affordable Care Act. On December 18, 2019, the U.S. Court of Appeals for the 5th Circuit upheld the District Court ruling that the individual mandate was unconstitutional and remanded the case back to the District Court to determine whether the remaining provisions of the Affordable Care Act are invalid as well. However, in March 2020, before the District Court could rule on the remaining provisions of the Affordable Care Act, the U.S. Supreme Court agreed to review the case. In November 2020, the U.S. Supreme Court heard oral arguments and is expected to rule on the case in its current session, which began in October 2020. Although the U.S. Supreme Court has not yet ruled on the constitutionality of the Affordable Care Act, on January 28, 2021, President Biden issued an executive order to initiate a special enrollment period from February 15, 2021 through May 15, 2021 for purposes of obtaining health insurance coverage through the Affordable Care Act marketplace. It is unclear how the Supreme Court ruling, other such litigation and healthcare reform measures will impact the Affordable Care Act and our business.

Further, we believe that future coverage and reimbursement will likely be subject to increased restrictions both in the U.S. and in international markets. For example, in the U.S., recent health reform measures have resulted in reductions in Medicare and other healthcare funding, and there have been several recent U.S. Congressional inquiries and legislation designed to, among other things, reform government program reimbursement methodologies for medicines and bring more transparency to drug pricing. Such restrictions may include legislative proposals seeking to reduce drug prices (e.g., by placing limits on pharmaceutical price increases and tying Medicare Part B drug prices to international drug prices), increase competition (e.g., by allowing for personal importation of drugs from Canada), lower out-of-pocket drug costs for patients (e.g., by capping Medicare Part D beneficiary out-of-pocket pharmacy expenses) and increase patient access to lower-cost generic and biosimilar drugs. In November 2020, the U.S. Department of Health and Human Services issued a final rule modifying the anti-kickback law safe harbors for plans, pharmacies, and pharmaceutical benefit managers. At the state level, legislatures have increasingly passed legislation and implemented regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. Third-party coverage and reimbursement for medicines may not be available or adequate in either the U.S. or international markets, and third-party payers, whether foreign or domestic, or governmental or commercial, may allocate their resources to address the current COVID-19 Pandemic or experience delays or disruptions in their ability to devote resources to coverage and reimbursement matters related to our products or medicines as a result of the COVID-19 Pandemic, which would negatively affect the potential commercial success of our products, our revenue and our profits.

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If we cannot manufacture our medicines or contract with a third party to manufacture our medicines at costs that allow us to charge competitive prices to buyers, we cannot market our products profitably.

To successfully commercialize any of our medicines, we would need to optimize and manage large-scale commercial manufacturing capabilities either on a standalone basis or through a third-party manufacturer. We rely on third-party manufacturers to supply the drug substance and drug product for TEGSEDI and drug product for WAYLIVRA. Any delays or disruption to our own or third-party commercial manufacturing capabilities, including any interruption to our supply chain as a result of the current COVID-19 Pandemic, could limit the commercial success of our medicines.

In addition, as our drug development pipeline increases and matures, we will have a greater need for clinical trial and commercial manufacturing capacity. We have limited experience manufacturing pharmaceutical products of the chemical class represented by our medicines, called oligonucleotides, on a commercial scale for the systemic administration of a medicine. There are a small number of suppliers for certain capital equipment and raw materials that we use to manufacture our medicines, and some of these suppliers will need to increase their scale of production to meet our projected needs for commercial manufacturing. Further, we must continue to improve our manufacturing processes to allow us to reduce our drug costs. We or our partners may not be able to manufacture our medicines at a cost or in quantities necessary to make commercially successful products.

Also, manufacturers, including us, must adhere to the FDA’s cGMP regulations and similar regulations in foreign countries, which the applicable regulatory authorities enforce through facilities inspection programs. We, our partners and our contract manufacturers may not comply or maintain compliance with cGMP, or similar foreign regulations. Non-compliance could significantly delay or prevent receipt of marketing authorizations for our medicines, including authorizations for SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development, or result in enforcement action after authorization that could limit the commercial success of our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development.

Risks Related to the Development and Regulatory Approval of our Medicines

If we or our partners fail to obtain regulatory approval for our medicines and additional approvals for SPINRAZA, TEGSEDI and WAYLIVRA, we or our partners cannot sell them in the applicable markets.

We cannot guarantee that any of our medicines will be considered safe and effective or will be approved for commercialization. In addition, it is possible that SPINRAZA, TEGSEDI and WAYLIVRA may not be approved in additional markets or for additional indications. We and our partners must conduct time-consuming, extensive and costly clinical studies to demonstrate the safety and efficacy of each of our medicines before they can be approved or receive additional approvals for sale. We and our partners must conduct these studies in compliance with FDA regulations and with comparable regulations in other countries.

We and our partners may not obtain necessary regulatory approvals on a timely basis, if at all, for our medicines. It is possible that regulatory agencies will not approve our medicines for marketing or SPINRAZA, TEGSEDI or WAYLIVRA in additional markets or for additional indications. If the FDA or another regulatory agency believes that we or our partners have not sufficiently demonstrated the safety or efficacy of any of our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, or our medicines in development, the agency will not approve the specific medicine or will require additional studies, which can be time consuming and expensive and which will delay or harm commercialization of the medicine. For example, in August 2018 we received a complete response letter from the FDA regarding the new drug application for WAYLIVRA in which the FDA determined that the safety concerns identified with WAYLIVRA in our clinical development program outweighed the expected benefits of triglyceride lowering in patients with FCS. We also received a Non-W from Health Canada for WAYLIVRA in November 2018. We are engaged with the FDA and plan to work with Health Canada to confirm a path forward for WAYLIVRA.

The FDA or other comparable foreign regulatory authorities can delay, limit or deny approval of a medicine for many reasons, including:

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Failure to receive marketing authorization for our medicines, or failure to receive additional marketing authorizations for SPINRAZA, TEGSEDI or WAYLIVRA, or delays in these authorizations could prevent or delay commercial introduction of the medicine, and, as a result, could negatively impact our ability to generate revenue from product sales.

If the results of clinical testing indicate that any of our medicines are not suitable for commercial use, we may need to abandon one or more of our drug development programs.

Drug discovery and development has inherent risks and the historical failure rate for drugs is high. Antisense medicines are a relatively new approach to therapeutics. If we cannot demonstrate that our medicines are safe and effective for human use in the intended indication, we may need to abandon one or more of our drug development programs.

In the past, we have invested in clinical studies of medicines that have not met the primary clinical end points in their Phase 3 studies. Similar results could occur in clinical studies for our medicines, including the studies of tominersen, tofersen, pelacarsen, IONIS-TTR-LRx and IONIS-APOCIII-LRx. If any of our medicines in clinical studies, including tominersen, tofersen, pelacarsen,, IONIS-TTR-LRx and IONIS-APOCIII-LRx, do not show sufficient efficacy in patients with the targeted indication, it could negatively impact our development and commercialization goals for these medicines and our stock price could decline.

Even if our medicines are successful in preclinical and human clinical studies, the medicines may not be successful in late-stage clinical studies.

Successful results in preclinical or initial human clinical studies, including the Phase 2 results for some of our medicines in development, may not predict the results of subsequent clinical studies, including the studies of tominersen, tofersen, pelacarsen, IONIS-TTR-LRx and IONIS-APOCIII-LRx. There are a number of factors that could cause a clinical study to fail or be delayed, including:

● the clinical study may produce negative or inconclusive results;

● enrollment in our clinical studies may be slower than we anticipate;

● enrollment in our clinical studies may be slower than we anticipate;

● a clinical study site may deviate from the protocol for the study;

● the cost of our clinical studies may be greater than we anticipate;

The current COVID-19 Pandemic could make some of these factors more likely to occur.

In addition, our current medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, are chemically similar to each other. As a result, a safety observation we encounter with one of our medicines could have, or be perceived by a regulatory authority to have, an impact on a different medicine we are developing. This could cause the FDA and other regulators to ask questions or take actions that could harm or delay our ability to develop and commercialize our medicines or increase our costs. For example, the FDA or other regulatory agencies could request, among other things, any of the following regarding one of our medicines: additional information or commitments before we can start or continue a clinical study, protocol amendments, increased safety monitoring, additional product labeling information, and post-approval commitments. This happened in connection with the conditional marketing approval for WAYLIVRA in the EU, as the EC is requiring us to conduct a post-authorization safety study to evaluate the safety of WAYLIVRA on thrombocytopenia and bleeding in FCS patients taking WAYLIVRA. We have an ongoing OLE extension study of WAYLIVRA in patients with FCS and an OLE study of TEGSEDI in patients with hATTR, and an early access program, or EAP, for WAYLIVRA. Adverse events or results from these studies or the EAPs could negatively impact our pending or future marketing approval applications for WAYLIVRA and TEGSEDI in patients with FCS or hATTR amyloidosis or the commercial opportunity for WAYLIVRA or TEGSEDI.

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Any failure or delay in the clinical studies, including the studies of tominersen, tofersen, pelacarsen, IONIS-TTR-LRx and IONIS-APOCIII-LRx, could reduce the commercial potential or viability of our medicines.

We depend on third parties to conduct our clinical studies for our medicines and any failure of those parties to fulfill their obligations could adversely affect our development and commercialization plans.

We depend on independent clinical investigators, contract research organizations and other third-party service providers to conduct our clinical studies for our medicines and expect to continue to do so in the future. For example, we use clinical research organizations, such as Pharmaceutical Research Associates, Inc., Icon Clinical Research Limited, Syneos Health, Inc., PPD and Medpace for the clinical studies for our medicines, including tominersen, tofersen, pelacarsen, IONIS-TTR-LRx and IONIS-APOCIII-LRx. We rely heavily on these parties for successful execution of our clinical studies, but do not control many aspects of their activities. For example, the investigators are not our employees. However, we are responsible for ensuring that these third parties conduct each of our clinical studies in accordance with the general investigational plan and approved protocols for the study. Third parties may not complete activities on schedule or may not conduct our clinical studies in accordance with regulatory requirements or our stated protocols. The failure of these third parties to carry out their obligations, including as a result of delays or disruption caused by the current COVID-19 Pandemic that may affect the third party’s ability to conduct the clinical studies for our medicines, or a termination of our relationship with these third parties could delay or prevent the development, marketing authorization and commercialization of our medicines or additional marketing authorizations for TEGSEDI and WAYLIVRA.

Since corporate partnering is a significant part of our strategy to fund the advancement and commercialization of our development programs, if any of our collaborative partners fail to fund our collaborative programs, or if we cannot obtain additional partners, we may have to delay or stop progress on our drug development programs.

To date, corporate partnering has played a significant role in our strategy to fund our development programs and to add key development resources. We plan to continue to rely on additional collaborative arrangements to develop and commercialize many of our unpartnered medicines. However, we may not be able to negotiate favorable collaborative arrangements for these drug programs. If we cannot continue to secure additional collaborative partners, our revenues could decrease and the development of our medicines could suffer.

Our corporate partners are developing and/or funding many of the medicines in our development pipeline. For example, we are relying on:

● Roche for development and funding of tominersen;

● Novartis for development and funding of pelacarsen; and

● Biogen for development and funding of tofersen.

If any of these pharmaceutical companies stops developing and/or funding these medicines, our business could suffer and we may not have, or be willing to dedicate, the resources available to develop these medicines on our own. Our collaborators can terminate their relationships with us under certain circumstances, many of which are outside of our control. For example, as part of a reprioritization of its pipeline and strategic review of its rare disease business, GSK declined its option to license TEGSEDI and IONIS-FB-LRx.

Even with funding from corporate partners, if our partners do not effectively perform their obligations under our agreements with them, it would delay or stop the progress of our drug development and commercial programs.

In addition to receiving funding, we enter into collaborative arrangements with third parties to:

● conduct clinical studies;

● seek and obtain marketing authorization; and

● manufacture, market and sell our medicines.

Once we have secured a collaborative arrangement to further develop and commercialize one of our drug development programs, such as our collaborations with AstraZeneca, Bayer, Biogen, GSK, Janssen, Novartis, Pfizer and Roche, these collaborations may not continue or result in commercialized medicines, or may not progress as quickly as we first anticipated.

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For example, a collaborator such as AstraZeneca, Bayer, Biogen, GSK, Janssen, Novartis, Pfizer or Roche, could determine that it is in its financial interest to:

If any of these occur, it could affect our partner’s commitment to the collaboration with us and could delay or otherwise negatively affect the commercialization of our medicines, including SPINRAZA, tominersen, pelacarsen and tofersen.

If we do not progress in our programs as anticipated, the price of our securities could decrease.

For planning purposes, we estimate and may disclose the timing of a variety of clinical, regulatory and other milestones, such as when we anticipate a certain medicine will enter clinical trials, when we anticipate completing a clinical study, or when we anticipate filing an application for, or obtaining, marketing authorization, or when we or our partners plan to commercially launch a medicine. We base our estimates on present facts and a variety of assumptions, many of which are outside of our control, including the current COVID-19 Pandemic. If we do not achieve milestones in accordance with our or our investors’ or securities analysts’ expectations, including milestones related to SPINRAZA, TEGSEDI, WAYLIVRA, tominersen, tofersen, pelacarsen, IONIS-TTR-LRx and IONIS-APOCIII-LRx, the price of our securities could decrease.

Risks Associated with our Businesses as a Whole

Risks related to our financial results

We have incurred losses, and our business will suffer if we fail to consistently achieve profitability in the future.

Because drug discovery and development requires substantial lead-time and money prior to commercialization, our expenses have generally exceeded our revenue since we were founded in January 1989. As of December 31, 2020, we had an accumulated deficit of approximately $1.2 billion and stockholders’ equity of approximately $0.8 billion. Most of our historical losses resulted from costs incurred in connection with our research and development programs and from selling, general and administrative costs associated with our operations. Most of our income has come from collaborative arrangements, including commercial revenue from royalties and R&D revenue, with additional income from the sale or licensing of our patents, as well as interest income. If we do not continue to earn substantial revenue, we may incur additional operating losses in the future. We may not successfully develop any additional products or achieve or sustain future profitability.

If we fail to obtain timely funding, we may need to curtail or abandon some of our programs.

Many of our medicines are undergoing clinical studies or are in the early stages of research and development. Most of our drug programs will require significant additional research, development, manufacturing, preclinical and clinical testing, marketing authorization, preclinical activities and commitment of significant additional resources prior to their successful commercialization. These activities will require significant cash. As of December 31, 2020, we had cash, cash equivalents and short-term investments equal to $1.9 billion. If we or our partners do not meet our goals to successfully commercialize our medicines, including SPINRAZA, TEGSEDI and WAYLIVRA, or to license certain medicines and proprietary technologies, we will need additional funding in the future. Our future capital requirements will depend on many factors, such as the following:

● successful commercialization of SPINRAZA, TEGSEDI and WAYLIVRA;

● additional marketing approvals for WAYLIVRA and TEGSEDI;

● the size of our programs and progress with preclinical and clinical studies;

● the time and costs involved in obtaining marketing authorizations; and

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If we need additional funds, we may need to raise them through public or private financing. Additional financing may not be available at all or on acceptable terms. If we raise additional funds by issuing equity securities, the shares of existing stockholders will be diluted and the price, as well as the price of our other securities, may decline. If adequate funds are not available or not available on acceptable terms, we may have to cut back on one or more of our research, drug discovery or development programs. Alternatively, we may obtain funds through arrangements with collaborative partners or others, which could require us to give up rights to certain of our technologies or medicines.

Risks related to our intellectual property

If we cannot protect our patent rights or our other proprietary rights, others may compete more effectively against us.

Our success depends to a significant degree upon whether we can continue to develop, secure and maintain intellectual property rights to proprietary products and services. However, we may not receive issued patents on any of our pending patent applications in the U.S. or in other countries and we may not be able to obtain, maintain or enforce our patents and other intellectual property rights which could impact our ability to compete effectively. In addition, the scope of any of our issued patents may not be sufficiently broad to provide us with a competitive advantage. Furthermore, other parties may successfully challenge, invalidate or circumvent our issued patents or patents licensed to us so that our patent rights do not create an effective competitive barrier or revenue source.

We cannot be certain that the U.S. Patent and Trademark Office, or U.S. PTO, and courts in the U.S. or the patent offices and courts in foreign countries will consider the claims in our patents and applications covering SPINRAZA, TEGSEDI, WAYLIVRA, or any of our medicines in development as patentable. Method-of-use patents protect the use of a product for the specified method. This type of patent does not prevent a competitor from making and marketing a product that is identical to our product for an indication that is outside the scope of the patented method. Moreover, even if competitors do not actively promote their product for our targeted indications, physicians may prescribe these products off-label. Although off-label prescriptions may infringe or contribute to the infringement of method-of-use patents, the practice is common and such infringement is difficult to prevent, including through legal action.

If we or any licensor partner loses or cannot obtain patent protection for SPINRAZA, TEGSEDI, WAYLIVRA, or any of our other medicines in development, it could have a material adverse impact on our business.

Intellectual property litigation could be expensive and prevent us from pursuing our programs.

From time to time we have to defend our intellectual property rights. If we are involved in an intellectual property dispute, we may need to litigate to defend our rights or assert them against others. Disputes can involve arbitration, litigation or proceedings declared by the U.S. PTO or the International Trade Commission or foreign patent authorities. Even if resolved in our favor, litigation or other legal proceedings relating to intellectual property claims may cause us to incur significant expenses and could distract our technical and management personnel from their normal responsibilities. In addition, there could be public announcements of the results of hearings, motions or other interim proceedings or developments and if securities analysts or investors perceive these results to be negative, it could have a substantial adverse effect on the price of our common stock.

If a third-party claims that our medicines or technology infringe its patents or other intellectual property rights, we may have to discontinue an important product or product line, alter our products and processes, pay license fees or cease certain activities. We may not be able to obtain a license to needed intellectual property on favorable terms, if at all. There are many patents issued or applied for in the biotechnology industry, and we may not be aware of patents or patent applications held by others that relate to our business. This is especially true since patent applications in the U.S. are filed confidentially for the first 18 months. Moreover, the validity and breadth of biotechnology patents involve complex legal and factual questions for which important legal issues remain.

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Risks related to our business strategy and personnel

If we fail to successfully integrate Akcea’s business and operations, it may adversely affect our future results.

We believe our Akcea Acquisition will result in certain benefits, including a single vision and set of strategic priorities, led by one team, accelerating our next phase of growth and positioning us to more effectively deliver our medicines to patients. Under this transaction, Ionis will now retain more value from Akcea’s pipeline and commercial products, further strengthening our financial position and supporting continued investments in our future. The success of the transaction will depend on our ability to realize these anticipated benefits. We may fail to realize the anticipated benefits of the Akcea Acquisition for a variety of reasons, including the following:

● disruptions to Akcea’s commercial operations;

● potential incompatibility of technologies and systems;

● the loss of key employees.

If our management transition is not successful our business could suffer.

In January 2020, Dr. Crooke, our founder and Chief Executive Officer, transitioned from Chief Executive Officer to Executive Chairman of our Board of Directors. As Executive Chairman, Dr. Crooke continues to be responsible for the activities of the board and remains active in the company, providing strategic advice and continuing to participate in the scientific activities. Starting in January 2020, Dr. Monia, who had been our Chief Operating Officer from January 2018 to January 2020 and has been a member of our team since our founding over 30 years ago, serves as our Chief Executive Officer. Following our 2021 Annual Meeting of Stockholders in June, Dr. Crooke will retire from Ionis and its board of directors but will continue to serve as a scientific advisor. If this transition is not successful, our business could suffer.

The loss of key personnel, or the inability to attract and retain highly skilled personnel, could make it more difficult to run our business and reduce our likelihood of success.

We are dependent on the principal members of our management and scientific staff. We do not have employment agreements with any of our executive officers that would prevent them from leaving us. The loss of our management and key scientific employees might slow the achievement of important research and development goals. It is also critical to our success that we recruit and retain qualified scientific personnel to perform research and development work. We may not be able to attract and retain skilled and experienced scientific personnel on acceptable terms because of intense competition for experienced scientists among many pharmaceutical and health care companies, universities and non-profit research institutions. In addition, failure to succeed in clinical studies may make it more challenging to recruit and retain qualified scientific personnel. Similarly, if we cannot recruit and retain qualified marketing, sales and distribution personnel, our ability to effectively implement our new commercial strategy following the Akcea Acquisition will be adversely affected.

Risks related to taxes

Our ability to use our net operating loss carryovers and certain other tax attributes may be limited.

Under the Internal Revenue Code of 1986, as amended, or the Code, a corporation is generally allowed a deduction for net operating losses, or NOLs, carried over from a prior taxable year. Under that provision, we can carryforward our NOLs to offset our future taxable income, if any, until such NOLs are used or expire. The same is true of other unused tax attributes, such as tax credits.

Under the Tax Cut and Jobs Act of 2017, or the Tax Act, as modified by the Coronavirus Aid, Relief, and Economic Security Act, or the CARES Act, U.S. federal net operating losses incurred in 2018 and in future years may be carried forward indefinitely, but the deductibility of such U.S. federal net operating losses is limited to 80 percent of taxable income beginning in 2021. It is uncertain if and to what extent various states will conform to the federal Tax Act or the CARES Act. The CARES Act also reinstated the net operating loss carryback provisions whereby net operating losses incurred in calendar tax years 2018, 2019 and 2020 may be carried back to offset taxable income of the five tax years preceding the year of the loss.

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At the state level, there may be periods during which the use of net operating losses is suspended or otherwise limited, which could accelerate or permanently increase state taxes owed. For example, in June 2020, California enacted Assembly Bill 85 (AB 85), which suspends NOLs and limits credit utilization to $5 million per year for the 2020, 2021 and 2022 tax years. AB 85 did not have a material impact on our 2020 tax provision, but it is possible that it may in future years.

In addition, under Sections 382 and 383 of the Code, and corresponding provisions of state law, if a corporation undergoes an “ownership change,” which is generally defined as a greater than 50 percent change, by value, in its equity ownership over a three-year period, the corporation’s ability to use its pre-change net operating loss carryforwards and other pre-change tax attributes to offset its post-change income or taxes may be limited. We may experience ownership changes in the future as a result of subsequent shifts in our stock ownership, some of which may be outside of our control. If an ownership change occurs and our ability to use our net operating loss carryforwards or other tax attributes is materially limited, it would harm our future operating results by effectively increasing our future tax obligations. As a result of the Akcea Acquisition, we will be subject to the Separate Return Limitation Year, or SRLY, Rules. Under SRLY, our utilization of Akcea’s pre-acquisition net operating loss and tax credit carryforwards will be limited to the amount of income that Akcea contributes to our consolidated taxable income. The Akcea pre-acquisition tax attributes cannot be used to offset any of the income that Ionis contributes to our consolidated taxable income.

We have assessed our valuation allowances requirements, both federal and state, due to the Akcea Acquisition, and have also assessed whether Akcea may rejoin our consolidated tax group. For details regarding these assessments, see Note 5, Income Taxes, in the Notes to the Consolidated Financial Statements.

Our future taxable income could be impacted by changes in tax laws, regulations and treaties.

A change in tax laws, treaties or regulations, or their interpretation, of any country in which we operate could materially affect us.

We could be subject to additional tax liabilities.

We are subject to U.S. federal, state, local and sales taxes in the U.S. and foreign income taxes, withholding taxes and transaction taxes in foreign jurisdictions. Significant judgment is required in evaluating our tax positions and our worldwide provision for taxes. During the ordinary course of business, there are many activities and transactions for which the ultimate tax determination is uncertain. In addition, our tax obligations and effective tax rates could be adversely affected by changes in the relevant tax, accounting and other laws, regulations, principles and interpretations, including those relating to income tax nexus, by recognizing tax losses or lower than anticipated earnings in jurisdictions where we have lower statutory rates and higher than anticipated earnings in jurisdictions where we have higher statutory rates, by changes in foreign currency exchange rates, or by changes in the valuation of our deferred tax assets and liabilities. We may be audited in various jurisdictions, and such jurisdictions may assess additional taxes, sales taxes and value-added taxes against us. Although we believe our tax estimates are reasonable, the final determination of any tax audits or litigation could be materially different from our historical tax provisions and accruals, which could have a material adverse effect on our operating results or cash flows in the period for which a determination is made.

General risk factors

If the price of our securities continues to be highly volatile, this could make it harder for you to liquidate your investment and could increase your risk of suffering a loss.

The market price of our common stock, like that of the securities of many other biopharmaceutical companies, has been and is likely to continue to be highly volatile. These fluctuations in our common stock price may significantly affect the trading price of our securities. During the 12 months preceding December 31, 2020, the market price of our common stock ranged from $64.34 to $39.32 per share. Many factors can affect the market price of our securities, including, for example, fluctuations in our operating results, announcements of collaborations, clinical study results, technological innovations or new products being developed by us or our competitors, the commercial success of our approved medicines, governmental regulation, marketing authorizations, changes in payers’ reimbursement policies, developments in patent or other proprietary rights and public concern regarding the safety of our medicines.

The current COVID-19 Pandemic has caused a significant disruption of global financial markets and has resulted in increased volatility in the trading price of our common stock. Additionally, broad market and industry factors may also materially harm the market price of our common stock irrespective of our operating performance. The stock market in general, and NASDAQ and the market for biotechnology companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of the particular companies affected. The trading prices and valuations of these stocks, and of ours, may not be predictable. A loss of investor confidence in the market for biotechnology or pharmaceutical stocks or the stocks of other companies which investors perceive to be similar to us, the opportunities in the biotechnology and pharmaceutical market or the stock market in general, could depress our stock price regardless of our business, prospects, financial conditions or results of operations.

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Provisions in our certificate of incorporation, convertible notes documents, call spread hedge transaction documents and Delaware law may prevent stockholders from receiving a premium for their shares.

Our certificate of incorporation provides for classified terms for the members of our board of directors. Our certificate also includes a provision that requires at least 66 2/3 percent of our voting stockholders to approve a merger or certain other business transactions with, or proposed by, any holder of 15 percent or more of our voting stock, except in cases where certain directors approve the transaction or certain minimum price criteria and other procedural requirements are met.

Our certificate of incorporation also requires that any action required or permitted to be taken by our stockholders must be taken at a duly called annual or special meeting of stockholders and may not be taken by written consent. In addition, only our board of directors, chairman of the board or chief executive officer can call special meetings of our stockholders. We have in the past, and may in the future, implement a stockholders’ rights plan, also called a poison pill, which could make it uneconomical for a third party to acquire our company on a hostile basis. In addition, our board of directors has the authority to fix the rights and preferences of, and issue shares of preferred stock, which may have the effect of delaying or preventing a change in control of our company without action by our stockholders.

The provisions of our convertible senior notes could make it more difficult or more expensive for a third party to acquire us. Upon the occurrence of certain transactions constituting a fundamental change, holders of the notes will have the right, at their option, to require us to repurchase all of their notes or a portion of their notes, which may discourage certain types of transactions in which our stockholders might otherwise receive a premium for their shares over the then current market prices.

In December 2019, we entered into privately negotiated exchange and/or subscription agreements with certain new investors and certain holders of our existing 1% Notes to exchange $375.6 million of our 1% Notes for $439.3 million of our 0.125% Notes, and to issue $109.5 million of our 0.125% Notes. Additionally, in connection with the pricing of our 0.125% Notes, we entered into call spread transactions in which we purchased note hedges and sold warrants. Terminating or unwinding the call spread transactions could require us to make substantial payments to the counterparties under those agreements or may increase our stock price. The costs or any increase in stock price that may arise from terminating or unwinding such agreements could make an acquisition of our company significantly more expensive to the purchaser.

These provisions, as well as Delaware law, including Section 203 of the Delaware General Corporation Law, and other of our agreements, may discourage certain types of transactions in which our stockholders might otherwise receive a premium for their shares over then current market prices, and may limit the ability of our stockholders to approve transactions that they think may be in their best interests.

Future sales of our common stock in the public market could adversely affect the trading price of our securities.

Future sales of substantial amounts of our common stock in the public market, or the perception that such sales could occur, could adversely affect trading prices of our securities. For example, we may issue approximately 11.2 million shares of our common stock upon conversion of our convertible senior notes and up to 6.6 million shares may be issued in connection with the warrant transactions we entered into in connection with the issuance of our 0.125% Notes, in each case subject to customary anti-dilution adjustments. The addition of any of these shares into the public market may have an adverse effect on the price of our securities.

In addition, pursuant to the call spread transactions we entered into in connection with the pricing of our 0.125% Notes, the counterparties are likely to modify their hedge positions from time to time at or prior to the conversion or maturity of the notes by purchasing and selling shares of our common stock, other of our securities, or other instruments, including over-the-counter derivative instruments, that they may wish to use in connection with such hedging, which may have a negative effect on the conversion value of those notes and an adverse impact on the trading price of our common stock. The call spread transactions are expected generally to reduce potential dilution to holders of our common stock upon any conversion of our 0.125% Notes or offset any cash payments we are required to make in excess of the principal amount of the converted 0.125% Notes, as the case may be. However, the warrant transactions could separately have a dilutive effect to the extent that the market value per share of our common stock exceeds the applicable strike price of the warrants.

We are exposed to potential product liability claims, and insurance against these claims may not be available to us at a reasonable rate in the future or at all.

Our business exposes us to potential product liability risks that are inherent in the testing, manufacturing, marketing and sale of therapeutic products, including potential product liability claims related to SPINRAZA, TEGSEDI and WAYLIVRA, and our medicines in development. We have clinical study insurance coverage and commercial product liability insurance coverage. However, this insurance coverage may not be adequate to cover claims against us, or be available to us at an acceptable cost, if at all. Regardless of their merit or eventual outcome, product liability claims may result in decreased demand for our medicines, injury to our reputation, withdrawal of clinical study volunteers and loss of revenues. Thus, whether or not we are insured, a product liability claim or product recall may result in losses that could be material.

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We are dependent on information technology systems, infrastructure and data, which exposes us to data security risks.

We are dependent upon our own and third-party information technology systems, infrastructure and data, including mobile technologies, to operate our business. The multitude and complexity of our computer systems may make them vulnerable to service interruption or destruction, disruption of data integrity, malicious intrusion, or random attacks. Likewise, data privacy or security incidents or breaches by employees or others may pose a risk that sensitive data, including our intellectual property, trade secrets or personal information of our employees, patients, customers or other business partners may be exposed to unauthorized persons or to the public. Cyber-attacks are increasing in their frequency, sophistication and intensity, with third-party phishing and social engineering attacks in particular increasing in connection with the COVID-19 Pandemic. Cyber-attacks could include the deployment of harmful malware, denial-of-service, social engineering and other means to affect service reliability and threaten data confidentiality, integrity and availability. Our business partners face similar risks and any security breach of their systems could adversely affect our security posture. A security breach or privacy violation that leads to disclosure or modification of or prevents access to patient information, including personally identifiable information or protected health information, could harm our reputation, compel us to comply with federal and state breach notification laws and foreign law equivalents, subject us to financial penalties and mandatory and costly corrective action, require us to verify the correctness of database contents and otherwise subject us to litigation or other liability under laws and regulations that protect personal data, any of which could disrupt our business and result in increased costs or loss of revenue. Moreover, the prevalent use of mobile devices that access confidential information increases the risk of data security breaches, which could lead to the loss of confidential information, trade secrets or other intellectual property. While we have invested, and continue to invest, in the protection of our data and information technology infrastructure, our efforts may not prevent service interruptions, or identify breaches in our systems, that could adversely affect our business and operations and result in the loss of critical or sensitive information, which could result in financial, legal, business or reputational harm to us. In addition, our liability insurance may not be sufficient in type or amount to cover us against claims related to security breaches, cyber-attacks and other related breaches.

Because we use biological materials, hazardous materials, chemicals and radioactive compounds, if we do not comply with laws regulating the protection of the environment and health and human safety, our business could be adversely affected.

Our research, development and manufacturing activities involve the use of potentially harmful biological materials as well as materials, chemicals and various radioactive compounds that could be hazardous to human health and safety or the environment. We store most of these materials and various wastes resulting from their use at our facilities in Carlsbad, California pending ultimate use and disposal. We cannot completely eliminate the risk of contamination, which could cause:

● interruption of our research, development and manufacturing efforts;

● injury to our employees and others;

● environmental damage resulting in costly clean up; and

In such an event, we may be held liable for any resulting damages, and any liability could exceed our resources. Although we carry insurance in amounts and types that we consider commercially reasonable, we do not have insurance coverage for losses relating to an interruption of our research, development or manufacturing efforts caused by contamination, and the coverage or coverage limits of our insurance policies may not be adequate. If our losses exceed our insurance coverage, our financial condition would be adversely affected.

If a natural or man-made disaster strikes our research, development or manufacturing facilities or otherwise affects our business, it could delay our progress developing and commercializing our medicines.

We manufacture most of our research and clinical supplies in a manufacturing facility located in Carlsbad, California. We manufacture the finished drug product for TEGSEDI and WAYLIVRA at third-party contract manufacturers. Biogen manufactures the finished drug product for SPINRAZA. The facilities and the equipment we, our partners and our contract manufacturers use to research, develop and manufacture our medicines would be costly to replace and could require substantial lead time to repair or replace. Our facilities or those of our partners or contract manufacturers may be harmed by natural or man-made disasters, including, without limitation, earthquakes, floods, fires, acts of terrorism and pandemics; and if such facilities are affected by a disaster, our development and commercialization efforts would be delayed. Although we possess property damage and business interruption insurance coverage, this insurance may not be sufficient to cover all of our potential losses and may not continue to be available to us on acceptable terms, or at all. In addition, our development and commercialization activities could be harmed or delayed by a shutdown of the U.S. government, including the FDA.

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Our business is subject to changing regulations for corporate governance and public disclosure that has increased both our costs and the risk of noncompliance.

Each year we are required to evaluate our internal controls systems in order to allow management to report on and our Independent Registered Public Accounting Firm to attest to, our internal controls as required by Section 404 of the Sarbanes-Oxley Act. As a result, we continue to incur additional expenses and divert our management’s time to comply with these regulations. In addition, if we cannot continue to comply with the requirements of Section 404 in a timely manner, we might be subject to sanctions or investigation by regulatory authorities, such as the SEC, the Public Company Accounting Oversight Board, or PCAOB, or The Nasdaq Global Select Market. Any such action could adversely affect our financial results and the market price of our common stock.

The SEC and other regulators have continued to adopt new rules and regulations and make additional changes to existing regulations that require our compliance. On July 21, 2010, the Dodd-Frank Wall Street Reform and Protection Act, or the Dodd-Frank Act, was enacted. There are significant corporate governance and executive compensation-related provisions in the Dodd-Frank Act that require the SEC to adopt, or where the SEC has adopted, additional rules and regulations in these areas such as “say on pay” and proxy access. Stockholder activism, the current political environment and the current high level of government intervention and regulatory reform may lead to substantial new regulations and disclosure obligations, which may lead to additional compliance costs and impact the manner in which we operate our business.

Negative conditions in the global credit markets and financial services and other industries may adversely affect our business.

The global credit markets, the financial services industry, the U.S. capital markets, and the U.S. economy as a whole are currently experiencing substantial turmoil and uncertainty characterized by unprecedented intervention by the U.S. federal government in response to the COVID-19 Pandemic. In the past, the failure, bankruptcy, or sale of various financial and other institutions created similar turmoil and uncertainty in such markets and industries. It is possible that a crisis in the global credit markets, the U.S. capital markets, the financial services industry or the U.S. economy may adversely affect our business, vendors and prospects, as well as our liquidity and financial condition. More specifically, our insurance carriers and insurance policies covering all aspects of our business may become financially unstable or may not be sufficient to cover any or all of our losses and may not continue to be available to us on acceptable terms, or at all.

A variety of risks associated with operating our business and marketing our medicines internationally could adversely affect our business.

In addition to our U.S. operations, we are commercializing TEGSEDI in the EU and Canada, and WAYLIVRA in the EU. We face risks associated with our international operations, including possible unfavorable regulatory, pricing and reimbursement, political, tax and labor conditions, which could harm our business. Because we have international operations we are subject to numerous risks associated with international business activities, including:

● difficulties in staffing and managing foreign operations;

● foreign government taxes, regulations and permit requirements;

● changes in diplomatic and trade relationships.

The United Kingdom’s exit from the E.U. could increase these risks.

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Our business activities outside of the U.S. are subject to the FCPA and similar anti-bribery or anti-corruption laws, regulations or rules of other countries in which we operate, including the United Kingdom’s Bribery Act 2010. In many other countries, the healthcare providers who prescribe pharmaceuticals are employed by their government, and the purchasers of pharmaceuticals are government entities; therefore, any dealings with these prescribers and purchasers may be subject to regulation under the FCPA. There is no certainty that all employees and third-party business partners (including our distributors, wholesalers, agents, contractors and other partners) will comply with anti-bribery laws. In particular, we do not control the actions of manufacturers and other third-party agents, although we may be liable for their actions. Violation of these laws may result in civil or criminal sanctions, which could include monetary fines, criminal penalties, and disgorgement of past profits, which could have an adverse impact on our business and financial condition.

The impact on us of the vote by the United Kingdom to leave the European Union cannot be predicted.

The withdrawal of the UK from the EU, commonly referred to as “Brexit,” may adversely impact our ability to obtain regulatory approvals of our medicines in the EU, result in restrictions or imposition of taxes and duties for importing our medicines into the EU, and may require us to incur additional expenses in order to develop, manufacture and commercialize our medicines in the EU.

Following the result of a referendum in 2016, the UK left the EU on January 31, 2020. Pursuant to the formal withdrawal arrangements agreed between the UK and the EU, the UK was subject to a transition period that ended December 31, 2020, or the Transition Period, during which EU rules continued to apply. A trade and cooperation agreement, or the Trade and Cooperation Agreement, that outlines the future trading relationship between the UK and the EU was agreed in December 2020.

Since a significant proportion of the regulatory framework in the UK applicable to our business and our medicines is derived from EU directives and regulations, Brexit has had, and may continue to have, a material impact upon the regulatory regime with respect to the development, manufacture, importation, approval and commercialization of our medicines in the UK or the EU. For example, Great Britain is no longer covered by the centralized procedures for obtaining EU-wide marketing authorization from the EMA and, and a separate marketing authorization will be required to market our medicines in Great Britain. It is currently unclear whether the Medicines & Healthcare products Regulatory Agency in the UK is sufficiently prepared to handle the increased volume of marketing authorization applications that it is likely to receive. Any delay in obtaining, or an inability to obtain, any marketing approvals, as a result of Brexit or otherwise, would delay or prevent us from commercializing our medicines in the UK or the EU.

While the Trade and Cooperation Agreement provides for the tariff-free trade of medicinal products between the UK and the EU, there may be additional non-tariff costs to such trade which did not exist prior to the end of the Transition Period. Further, should the UK diverge from the EU from a regulatory perspective in relation to medicinal products, tariffs could be put into place in the future. We could therefore, both now and in the future, face significant additional expenses (when compared to the position prior to the end of the Transition Period) to operate our business.

Item 1B. Unresolved Staff Comments

Not applicable.

Item 2. Properties

As of February 18, 2021, the following are the primary facilities in which we operate:

Laboratory and office space facility Carlsbad, CA 176,000 Owned

Office and meeting space facility Carlsbad, CA 74,000 Owned

Manufacturing facility Carlsbad, CA 26,800 Owned

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Item 3. Legal Proceedings

For details of legal proceedings, see Note 9, Legal Proceedings, in the Notes to the Consolidated Financial Statements.

Item 4. Mine Safety Disclosures

Not applicable.

PART II

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

Market Information and Dividends

Our common stock is traded publicly through The Nasdaq Global Select Market under the symbol “IONS.” As of February 18, 2021, there were approximately 506 stockholders of record of our common stock. Because many of our shares are held by brokers and other institutions on behalf of stockholders, we are unable to estimate the total number of stockholders represented by these record holders.

We have never paid dividends and do not anticipate paying any dividends in the foreseeable future.

Performance Graph (1)

Set forth below is a table and chart comparing the total return on an indexed basis of $100 invested on December 31, 2015 in our common stock, the Nasdaq Composite Index (total return) and the Nasdaq Biotechnology Index. The total return assumes reinvestment of dividends.

* $100 invested on December 31, 2015 in stock or index, including reinvestment of dividends. Fiscal year ending December 31.

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COMPARISON OF 5 YEAR CUMULATIVE TOTAL RETURN

Among Ionis Pharmaceuticals, Inc., the Nasdaq Composite Index,

and the Nasdaq Biotechnology Index

________________

Item 6. Selected Financial Data

Refer to our financial data contained within Item 7, Management’s Discussion and Analysis, our financial statements and within other parts of this document.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

This financial review presents our operating results for each of the two years in the period ended December 31, 2020, and our financial condition at December 31, 2020. Refer to our 2019 Form 10-K for our results of operations for 2019 compared to 2018. Except for the historical information contained herein, the following discussion contains forward-looking statements that are subject to known and unknown risks, uncertainties and other factors that may cause our actual results to differ materially from those expressed or implied by such forward-looking statements. We discuss such risks, uncertainties and other factors throughout this report and specifically under Item 1A of Part I of this report, “Risk Factors.” In addition, the following review should be read in conjunction with the information presented in our consolidated financial statements and the related notes to our consolidated financial statements as indexed on page F-1.

Overview

As noted in our Business Overview in Part I of this report, for more than 30 years, we have been a leader in RNA-targeted therapy and believe our medicines are pioneering new markets, changing standards of care and transforming the lives of people with devastating diseases. We currently have three marketed medicines and a late-stage pipeline primarily focused on two core franchises: neurology and cardiometabolic. Our scientific innovation began and continues with the knowledge that sick people depend on us, which fuels our vision of becoming one of the most successful biotechnology companies. For further details on our business refer to the Business section of Part I of this report.

Financial Highlights

The following is a summary of our financial results (in millions):

Year Ended December 31,

Income (loss) from operations $ (172.1 ) $ 365.9

Cash, cash equivalents and short-term investments $ 1,892.4 $ 2,499.5

Commercial revenue increased in 2020 compared to 2019 due to an increase in product sales from TEGSEDI and WAYLIVRA, primarily from major market launches in 2020. Our R&D revenue in 2019 was higher compared to 2020 primarily because of license fees we recognized in 2019. In 2019, we earned approximately $400 million of revenue from licensing vupanorsen to Pfizer and pelacarsen to Novartis.

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Our operating expenses for 2020 increased compared to 2019 principally due to our investments in the Phase 3 program for IONIS-TTR-LRx and our wholly owned pipeline. Additionally, we incurred approximately $90 million in costs related to the Akcea Acquisition and restructured European operations. The costs primarily consisted of severance and retention costs of $29 million and stock-based compensation expense for the acceleration of Akcea equity awards of $59 million.

Our net loss for 2020 included income tax expense of $317 million compared to $44 million in 2019. The increase was primarily due to a non-cash tax expense of $313 million related to an increase in the valuation allowance we recorded against our federal net deferred tax assets. As a result of the Akcea Acquisition, Ionis and Akcea will file their federal taxes on a consolidated basis beginning in the fourth quarter of 2020. We recorded a valuation allowance against all of Ionis’ federal net deferred tax assets in the fourth quarter of 2020, due largely to Akcea’s history of losses, and the expected impact of this on Ionis’ consolidated federal taxable income. We now maintain a valuation allowance against all our consolidated federal and state net deferred tax assets. See Note 5, Income Taxes, in the Notes to the Consolidated Financial Statements for further discussion on our valuation allowance assessment.

With $1.9 billion in cash and short-term investments at December 31, 2020, we believe we have the financial resources to execute on our strategic priorities for 2021 and beyond.

Business Segments

Through 2020, we had two operating segments, our Ionis Core segment and Akcea Therapeutics. Akcea was focused on developing and commercializing medicines to treat patients with serious and rare diseases. We have provided segment financial information and results for our Ionis Core segment and our Akcea Therapeutics segment based on the segregation of revenues and expenses that our chief decision maker reviewed to assess operating performance and to make operating decisions through 2020. We allocated a portion of Ionis’ development, R&D support and general and administrative expenses to Akcea for work Ionis performed on behalf of Akcea and we billed Akcea for these expenses. As a result of acquiring Akcea in the fourth quarter of 2020 we integrated Akcea operations within Ionis. Beginning in 2021, our chief decision maker began assessing operating performance and making operating decisions on a single segment basis, which we refer to as Ionis Pharmaceuticals.

Critical Accounting Estimates

We prepare our consolidated financial statements in conformity with accounting principles generally accepted in the United States. As such, we make certain estimates, judgments and assumptions that we believe are reasonable, based upon the information available to us. These judgments involve making estimates about the effect of matters that are inherently uncertain and may significantly impact our quarterly or annual results of operations and financial condition. Each quarter, our senior management reviews the development, selection and disclosure of such estimates with the audit committee of our board of directors. In the following paragraphs, we describe the specific risks associated with these critical accounting estimates and we caution that future events rarely develop exactly as one may expect, and that best estimates may require adjustment. Our significant accounting policies are outlined in Note 1, Organization and Significant Accounting Policies, in the Notes to the Consolidated Financial Statements.

The following are our significant accounting estimates, which we believe are the most critical to aid in fully understanding and evaluating our reported financial results:

● Estimating our income taxes.

The following are descriptions of our critical accounting estimates.

Revenue Recognition

We earn revenue from several sources. The judgements and estimates we make vary between each source of our revenue. The following is a summary of the critical accounting estimates we make with respect to each of our significant revenue sources.

Commercial Revenue: SPINRAZA royalties and Licensing and other royalty revenue

We estimate our commercial revenue from SPINRAZA royalties based on reporting we receive from Biogen each quarter. We use this reporting to calculate our royalty revenue based on our tiered contractual royalty rate for the given period based on annual cumulative net sales. We record our royalty revenue in the same period in which Biogen sells SPINRAZA. We also estimate commercial revenue from licensing and other royalty revenue.

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Commercial Revenue: Product sales, net

We added product sales from TEGSEDI to our commercial revenue in the fourth quarter of 2018 and we added product sales from WAYLIVRA to our commercial revenue in the third quarter of 2019. We recognize product sales in the period when our customer obtains control of our products. We record product sales at our net sales price, which includes estimated reserves for discounts, returns, chargebacks, rebates, co-pay assistance and other allowances that we offer under contracts between us and our customers, wholesalers, health care providers and other indirect customers. Actual amounts may vary from our estimates. Our historical reserve estimates have not been materially different from our actual amounts. The total reserves we estimated during 2020 and 2019 were not material to our financial results.

Research and development revenue under collaborative agreements

We recognize R&D revenue from numerous collaboration agreements. Our collaboration agreements typically contain multiple elements, or performance obligations, including technology licenses or options to obtain technology licenses, R&D services, and manufacturing services. Upon entering into a collaboration agreement, we are required to make the following judgements:

● Identifying the performance obligations contained in the agreement

Our assessment of what constitutes a separate performance obligation requires us to apply judgement. Specifically, we have to identify which goods and services we are required to provide under the contract are distinct.

● Determining the transaction price, including any variable consideration

To determine the transaction price, we review the amount of consideration we are eligible to earn under the agreement. We do not typically include any payments we may receive in the future in our initial transaction price since the payments are typically not probable because they are contingent upon certain future events.

We are required to reassess the total transaction price at each reporting period to determine if we should include additional payments in the transaction price that have become probable. For example, in the fourth quarter of 2020, we achieved a milestone payment for $7.5 million under our 2018 strategic neurology collaboration with Biogen. Prior to achieving this milestone payment, we did not consider this payment probable. Upon achieving the milestone payment, we reassessed the total transaction price of our 2018 strategic neurology collaboration. We added this milestone payment to our total transaction price under our collaboration.

● Allocating the transaction price to each of our performance obligations

When we allocate the transaction price to more than one performance obligation, we make estimates of the relative stand-alone selling price of each performance obligation because we do not typically sell our goods or services on a stand-alone basis. The estimate of the relative stand-alone selling price requires us in some cases to make significant judgements. For example, when we deliver a license at the start of an agreement, we use valuation methodologies, such as the relief from royalty method, to value the license. Under this method we are required to make estimates including: future sales, royalties on future product sales, contractual milestones, expenses, income taxes and discount rates. Additionally, when we estimate the selling price for R&D services, we make estimates, including: the number of internal hours we will spend on the services, the cost of work we and third parties will perform and the cost of clinical trial material we will use.

The R&D revenue we recognize each period is comprised of several types of revenue, including amortization from upfront payments, milestone payments, license fees and other services. Each of these types of revenue require us to make various judgements and estimates.

Amortization from Upfront Payments

We recognize revenue from the amortization of upfront payments as we perform R&D services. We use an input method to estimate the amount of revenue to recognize each period. This method requires us to make estimates of the total costs we expect to incur to complete our R&D services performance obligation or the total length of time it will take us to complete our R&D services performance obligation. If we change our estimates, we may have to adjust our revenue. Refer to Note 6, Collaborative Arrangements and Licensing Agreements, for further discussion of the cumulative catch up adjustment we made.

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Milestone Payments

When recognizing revenue related to milestone payments we typically make the following judgements and estimates:

License Fees

When we grant a license for a medicine in clinical development, we generally recognize as R&D revenue the total amount we determine to be the relative stand-alone selling price of a license when we deliver the license to our partner. We discuss the estimates we make related to the relative stand-alone selling price of a license in detail above under “Allocating the transaction price to each of our performance obligations”.

Estimated Liability for Clinical Development Costs

We have numerous medicines in preclinical studies and/or clinical trials at clinical sites throughout the world. On at least a quarterly basis, we estimate our liability for preclinical and clinical development costs we have incurred and services that we have received but for which we have not yet been billed and maintain an accrual to cover these costs. These costs primarily relate to third-party clinical management costs, laboratory and analysis costs, toxicology studies and investigator grants. We estimate our liability using assumptions about study and patient activities and the related expected expenses for those activities determined based on the contracted fees with our service providers. The assumptions we use represent our best estimates of the activity and expenses at the time of our accrual and involve inherent uncertainties and the application of our judgment. Upon settlement, these costs may differ materially from the amounts accrued in our consolidated financial statements. Our historical accrual estimates have not been materially different from our actual amounts.

Income Taxes

Ionis and Akcea have filed separate U.S. federal income tax returns since Akcea’s IPO in 2017. Accordingly, we were required to assess Ionis’ stand-alone and Akcea’s valuation allowances separately even though we consolidate Akcea’s financial results in our consolidated financial statements. However, as a result of the Akcea Acquisition, Ionis and Akcea will file a consolidated U.S. federal income tax return beginning in the fourth quarter of 2020, and we therefore assessed our U.S. federal valuation allowance requirements on a consolidated basis as of that period. We continue to assess the state portion of our valuation allowance on a consolidated basis.

We assessed our valuation allowance requirements and recorded a valuation allowance of $313 million against all of Ionis’ U.S. federal net deferred tax assets in the fourth quarter of 2020, due to uncertainties related to our ability to realize the tax benefits associated with these assets. This determination is based largely on Akcea rejoining the Ionis consolidated U.S. federal tax group in the fourth quarter of 2020. Due to Akcea’s historical and projected financial statement losses, and the expected negative impact this will have on Ionis’ consolidated taxable income, there is uncertainty of generating sufficient consolidated pre-tax income in future periods to realize the Ionis deferred tax benefits. It is also expected that Ionis’ pre-tax income in future periods may be lower due to significant investments in research and development associated with our pipeline of wholly owned medicines. We now maintain a valuation allowance against all our consolidated U.S. federal and state net deferred tax assets.

We evaluate our deferred tax assets quarterly to determine whether adjustments to the valuation allowance are appropriate due to changes in facts or circumstances, such as changes in expected future pre-tax earnings, tax law, interactions with taxing authorities and developments in case law. In making this evaluation, we rely on our recent history of pre-tax earnings. Our material assumptions are our forecasts of future pre-tax earnings and the nature and timing of future deductions and income represented by the deferred tax assets and liabilities, all of which involve the exercise of significant judgment. Although we believe our estimates are reasonable, we are required to use significant judgment in determining the appropriate amount of valuation allowance recorded against our deferred tax assets.

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Results of Operations

Below we have included our results of operations for 2020 compared to 2019. Refer to our 2019 Form 10-K for our results of operations for 2019 compared to 2018.

Years Ended December 31, 2020 and December 31, 2019

Revenue

Total revenue for 2020 was $729.3 million compared to $1.1 billion in 2019 and was comprised of the following (amounts in millions):

Year Ended December 31,

Revenue:

Commercial revenue:

Licensing and other royalty revenue 8.1 17.2

R&D revenue:

Amortization from upfront payments 79.6 146.2

In 2020, our commercial revenue increased compared to 2019 primarily due to increases in TEGSEDI and WAYLIVRA product sales, primarily from major market launches in 2020.

We earn our R&D revenue from multiple sources. Our R&D revenue can fluctuate depending on the timing of events. Our R&D revenue in 2020 included more than $165 million from our cardiometabolic disease franchise, including a $75 million milestone payment we earned from Pfizer in the fourth quarter of 2020. We also earned more than $125 million from our neurological disease franchise, primarily driven by several Biogen-partnered programs. Additionally, in November 2020, we completed an arbitration process with Alnylam. The arbitration panel awarded us $41 million for payments owed to us by Alnylam related to Alnylam’s agreement with Sanofi Genzyme. We recognized the $41 million payment from Alnylam as R&D revenue in the fourth quarter of 2020.

Our R&D revenue in 2019 included significant revenue from license fees, including $246 million for Pfizer’s license of vupanorsen and $150 million for Novartis’ license of pelacarsen. Additionally, our amortization from upfront payments for 2019 was higher compared to 2020 because it included amortization from collaborations for which we have completed our R&D services performance obligations in 2019.

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Operating Expenses

Operating expenses for 2020 were $901.3 million, and increased compared to $756.7 million for 2019. The increase was principally due to $89.6 million of operating expenses related to the Akcea Acquisition and restructured European operations, including non-cash stock-based compensation expense of $59.3 million related to the acceleration of all of Akcea’s equity award stock-based compensation expense and severance, retention and other expenses of $30.3 million. Excluding expenses related to the Akcea Acquisition and restructured European operations, our operating expenses increased primarily due to our investments in the Phase 3 program for IONIS-TTR-LRx and our wholly-owned pipeline.

Our operating expenses by segment were as follows (in millions):

Year Ended December 31,

Elimination of intercompany activity (51.9 ) (214.6 )

Non-cash compensation expense related to equity awards 230.1 146.6

In order to analyze and compare our results of operations to other similar companies, we believe it is important to exclude non-cash compensation expense related to equity awards from our operating expenses. We believe non-cash compensation expense related to equity awards is not indicative of our operating results or cash flows from our operations. Further, we internally evaluate the performance of our operations excluding it.

Cost of Products Sold

Our cost of products sold consisted of manufacturing costs, including certain fixed costs, transportation and freight, indirect overhead costs associated with the manufacturing and distribution of TEGSEDI and WAYLIVRA and certain associated period costs. Prior to the regulatory approval of TEGSEDI and WAYLIVRA, we expensed as R&D expense a significant portion of the cost of producing TEGSEDI and WAYLIVRA that we are using in the commercial launches. We expect cost of products sold to increase as we deplete these inventories.

Our cost of products sold by segment were as follows (in millions):

Year Ended December 31,

Ionis Core $ — $ —

Elimination of intercompany activity (8.9 ) (8.9 )

Non-cash compensation expense related to equity awards 1.9 0.4

Total cost of products sold $ 11.9 $ 4.3

Our cost of products sold increased in 2020 compared to 2019 because of the increase in associated product sales in the same periods. In its cost of products sold, Akcea includes the amortization for milestone payments it made to us related to the U.S. and European approvals of TEGSEDI. We eliminate this amortization in our consolidated results. All amounts exclude non-cash compensation expense related to equity awards.

We began recognizing cost of products sold for TEGSEDI in the third quarter of 2018 when TEGSEDI was approved and for WAYLIVRA in the second quarter of 2019 when WAYLIVRA was approved. Our cost of products sold increased in 2020 compared to 2019 primarily due to the increase in product sales of TEGSEDI and WAYLIVRA. All amounts exclude non-cash compensation expense related to equity awards.

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Research, Development and Patent Expenses

Our research, development and patent expenses consist of expenses for antisense drug discovery, antisense drug development, manufacturing and development chemistry and R&D support expenses.

The following table sets forth information on research, development and patent expenses (in millions):

Year Ended December 31,

Non-cash compensation expense related to equity awards 115.6 95.4

Total research, development and patent expenses $ 535.1 $ 465.7

Our research, development and patent expenses by segment were as follows (in millions):

Year Ended December 31,

Elimination of intercompany activity (43.0 ) (205.7 )

Non-cash compensation expense related to equity awards 115.6 95.4

Total research, development and patent expenses $ 535.1 $ 465.7

Antisense Drug Discovery

We use our proprietary antisense technology to generate information about the function of genes and to determine the value of genes as drug discovery targets. We use this information to direct our own antisense drug discovery research, and that of our partners. Antisense drug discovery is also the function that is responsible for advancing our antisense core technology. This function is also responsible for making investments in complementary technologies to expand the reach of antisense technology.

As we continue to advance our antisense technology, we are investing in our drug discovery programs to expand our pipeline.

Our antisense drug discovery expenses are part of our Ionis Core business segment and were as follows (in millions):

Year Ended December 31,

Non-cash compensation expense related to equity awards 24.2 20.9

Total antisense drug discovery expenses $ 113.4 $ 104.4

Antisense drug discovery expenses were slightly higher in 2020 compared to 2019 due to expenses we incurred related to advancing our research programs and investments we made in complementary technologies to expand the reach of our antisense technology. All amounts exclude non-cash compensation expense related to equity awards.

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Antisense Drug Development

The following table sets forth drug development expenses, including expenses for our marketed medicines and those in Phase 3 development for which we have incurred significant costs (in millions):

Year Ended December 31,

IONIS-APOCIII-LRx 5.6 7.6

Other antisense development projects 86.9 86.6

Development overhead expenses 85.9 74.0

Non-cash compensation expense related to equity awards 63.7 45.9

Total antisense drug development expenses $ 296.4 $ 252.4

Our development expenses increased in 2020 compared to 2019 primarily due to our broad Phase 3 program for IONIS-TTR-LRx, which we initiated in late 2019 and other medicines in our wholly-owned pipeline. These increases were slightly offset by decreases in expenses for TEGSEDI, WAYLIVRA, IONIS-FXI-LRx, IONIS-APOCIII-LRx and vupanorsen. We completed a Phase 2 study for IONIS-FXI-LRx in 2019 and we completed Phase 2 studies for IONIS-APOCIII-LRx and vupanorsen in early 2020. All amounts exclude non-cash compensation expense related to equity awards.

Our antisense drug development expenses by segment were as follows (in millions):

Year Ended December 31,

Elimination of intercompany activity (37.5 ) (200.0 )

Non-cash compensation expense related to equity awards 63.7 45.9

Total antisense drug development expenses $ 296.4 $ 252.4

We may conduct multiple clinical trials on a drug candidate, including multiple clinical trials for the various indications we may be studying. Furthermore, as we obtain results from trials, we may elect to discontinue clinical trials for certain drug candidates in certain indications in order to focus our resources on more promising drug candidates or indications. Our Phase 1 and Phase 2 programs are clinical research programs that fuel our Phase 3 pipeline. When our medicines are in Phase 1 or Phase 2 clinical trials, they are in a dynamic state in which we may adjust the development strategy for each medicine. Although we may characterize a medicine as “in Phase 1” or “in Phase 2,” it does not mean that we are conducting a single, well-defined study with dedicated resources. Instead, we allocate our internal resources on a shared basis across numerous medicines based on each medicine’s particular needs at that time. This means we are constantly shifting resources among medicines. Therefore, what we spend on each medicine during a particular period is usually a function of what is required to keep the medicines progressing in clinical development, not what medicines we think are most important. For example, the number of people required to start a new study is large, the number of people required to keep a study going is modest and the number of people required to finish a study is large. However, such fluctuations are not indicative of a shift in our emphasis from one medicine to another and cannot be used to accurately predict future costs for each medicine. And, because we always have numerous medicines in preclinical and early stage clinical research, the fluctuations in expenses from medicine to medicine, in large part, offset one another. If we partner a medicine, it may affect the size of a trial, its timing, its total cost and the timing of the related costs.

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Manufacturing and Development Chemistry

Expenditures in our manufacturing and development chemistry function consist primarily of personnel costs, specialized chemicals for oligonucleotide manufacturing, laboratory supplies and outside services. Our manufacturing and development chemistry function is responsible for providing drug supplies to antisense drug development and our collaboration partners. Our manufacturing procedures include testing to satisfy good laboratory and good manufacturing practice requirements.

Our manufacturing and development chemistry expenses were as follows (in millions):

Year Ended December 31,

Non-cash compensation expense related to equity awards 10.9 9.6

Total manufacturing and development chemistry expenses $ 66.8 $ 52.1

Manufacturing and development chemistry expenses increased in 2020 compared to 2019. The increase in manufacturing and development chemistry expenses was primarily related to manufacturing API for IONIS-TTR-LRx and IONIS-APOCIII-LRx for our Phase 3 studies. All amounts exclude non-cash compensation expense related to equity awards.

Our manufacturing and development chemistry expenses by segment were as follows (in millions):

Year Ended December 31,

Elimination of intercompany activity (5.3 ) (5.5 )

Non-cash compensation expense related to equity awards 10.9 9.6

Total manufacturing and development chemistry expenses $ 66.8 $ 52.1

R&D Support

In our research, development and patent expenses, we include support costs such as rent, repair and maintenance for buildings and equipment, utilities, depreciation of laboratory equipment and facilities, amortization of our intellectual property, informatics costs, procurement costs and waste disposal costs. We call these costs R&D support expenses.

The following table sets forth information on R&D support expenses (in millions):

Year Ended December 31,

Patent expenses 4.1 4.2

Computer software and licenses 2.9 1.1

Non-cash compensation expense related to equity awards 16.8 19.0

Total R&D support expenses $ 58.5 $ 56.8

R&D support expenses for 2020 increased compared to 2019 primarily due to costs from growth in our operations. All amounts exclude non-cash compensation expense related to equity awards.

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Our R&D support expenses by segment were as follows (in millions):

Year Ended December 31,

Akcea Therapeutics 22.7 8.3

Elimination of intercompany activity (0.2 ) (0.2 )

Non-cash compensation expense related to equity awards 16.8 19.0

Total R&D support expenses $ 58.5 $ 56.8

Selling, General and Administrative Expenses

Selling, general and administrative, or SG&A, expenses include personnel and outside costs associated with the pre-commercialization and commercialization activities for our medicines and costs to support our company, our employees and our stockholders including, legal, human resources, investor relations, and finance. Additionally, we include in selling, general and administrative expenses such costs as rent, repair and maintenance of buildings and equipment, depreciation and utilities costs that we need to support the corporate functions listed above. We also include fees we owe under our in-licensing agreements related to SPINRAZA.

The following table sets forth information on SG&A expenses (in millions):

Year Ended December 31,

Non-cash compensation expense related to equity awards 112.5 50.8

Total selling, general and administrative expenses $ 354.3 $ 286.6

SG&A expenses were slightly higher for 2020 compared to 2019 principally due to costs related to the Akcea Acquisition, including severance and retention costs and legal costs related to the Alnylam arbitration. These increases were mostly offset by reductions in travel and marketing events as a result of the COVID-19 pandemic. All amounts exclude non-cash compensation expense related to equity awards.

Our SG&A expenses by segment were as follows (in millions):

Year Ended December 31,

Non-cash compensation expense related to equity awards 112.5 50.8

Total selling general and administrative expenses $ 354.3 $ 286.6

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Akcea Therapeutics, Inc.

The following table sets forth information on operating expenses (in millions) for our Akcea Therapeutics business segment:

Year Ended December 31,

Cost of products sold $ 18.9 $ 12.8

Development and patent expenses 99.6 81.0

Selling, general and administrative expenses 155.0 156.9

Profit (loss) share for TEGSEDI commercialization activities (16.2 ) (37.3 )

Non-cash compensation expense related to equity awards 94.8 37.1

Total Akcea Therapeutics operating expenses $ 389.6 $ 450.5

See discussion of fluctuations of Akcea operating expenses in the operating expense sections above. All amounts exclude non-cash compensation expense related to equity awards.

Investment Income

Investment income for 2020 was $30.6 million compared to $52.0 million for 2019. The decrease in investment income was primarily due to a decrease in interest rates during 2020 compared to 2019.

Interest Expense

The following table sets forth information on interest expense (in millions):

Year Ended December 31,

Convertible senior notes:

Interest expense payable in cash 3.8 6.7

Interest on mortgage for primary R&D and manufacturing facilities 2.4 2.4

Total interest expense $ 45.0 $ 48.8

Our interest expense payable in cash decreased in 2020 compared 2019 because we exchanged a significant portion of our 1% Notes for 0.125% Notes in December 2019.

Gain on Investments

Gain on investments for 2020 was $16.5 million compared to $0.2 million for 2019. During the second and fourth quarters of 2020, we revalued our investments in three privately held companies, Dynacure, Suzhou-Ribo and Aro Biotherapeutics because the companies sold additional equity securities that were similar to the equity we own. Because of these observable price changes we recognized a $6.3 million gain on our investment in Dynacure, a $3.0 million gain on our investment in Suzhou-Ribo and a $5.5 million gain on our investment in Aro Biotherapeutics in our consolidated statement of operations during 2020 because the sales were at higher prices compared to our recorded value.

Early Retirement of Debt

As a result of the debt exchange we completed in December 2019, we recorded a $21.9 million non-cash loss on early retirement of debt, reflecting the early retirement of a portion of our 1% Notes. The non-cash loss on the early retirement of our debt is the difference between the amount paid to exchange our 1% Notes that we attributed to the liability component and the net carrying balance of the liability component at the time that we completed the debt exchange.

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Income Tax Expense (Benefit)

We had income tax expense of $316.7 million for 2020 compared to an income tax expense of $43.5 million for 2019. Our 2020 income tax expense primarily relates to a non-cash tax expense of $313 million related to an increasein the valuation allowance recorded against Ionis’ U.S. federal net deferred tax assets in the fourth quarter of 2020. We now maintain a valuation allowance against all our consolidated U.S. federal and state net deferred tax assets. See discussion of our valuation allowance under the section titled, Income Taxes, above in our discussion of our critical accounting estimates.

Net Income (Loss)

We generated a net loss of $486.8 million for 2020 compared to net income of $303.3 million for 2019. Our net loss for 2020 was primarily due to the valuation allowance we recorded as a result of the Akcea Acquisition, as discussed above in the income tax expense section. Also contributing to our net loss in 2020 was decreased revenue year-over-year, as discussed above in the revenue section and an increase in operating expenses year-over-year, as discussed above in the operating expense section.

Net Income (Loss) Attributable to Noncontrolling Interest in Akcea Therapeutics, Inc.

Our noncontrolling interest in Akcea on our statement of operations for 2020 was a net loss of $35.5 million compared to net income of $9.1 million for 2019.The net loss attributable to noncontrolling interest in Akcea for the year ended December 31, 2020, represents the portion of Akcea’s net loss that third parties owned for the period from January 1, 2020 until we acquired 100 percent of Akcea in October 2020. After our acquisition of Akcea in October 2020, we no longer recorded any adjustment related to noncontrolling interest for Akcea’s net loss. Akcea generated net income in 2019 primarily because it earned significant license fee revenue from Novartis and Pfizer.

Net Income (Loss) Attributable to Ionis Pharmaceuticals, Inc. Common Stockholders and Net Income (Loss) per Share

We had a net loss attributable to our common stockholders of $451.3 million for 2020 compared to net income of $294.1 million in 2019. Basic and diluted net loss per share for 2020 were each $3.23. Basic and diluted net income per share for 2019 was $2.12 and $2.08, respectively.

Liquidity and Capital Resources

We have financed our operations primarily from research and development collaborative agreements. We also finance our operations from commercial revenue from SPINRAZA royalties and product sales. From our inception through December 31, 2020, we have earned approximately $5.0 billion in revenue. We have also financed our operations through the sale of our equity securities and the issuance of long-term debt. From the time we were founded through December 31, 2020, we have raised net proceeds of approximately $2.0 billion from the sale of our equity securities. Additionally, we borrowed approximately $1.5 billion under long-term debt arrangements to finance a portion of our operations over the same time period.

Our key liquidity metrics and capital resources include our cash, cash equivalents and short-term investments, working capital and debt obligations. During 2020 we used a portion of our cash to complete the Akcea Acquisition. At December 31, 2020, we had $1.9 billion of cash and short-term investments on hand. We believe our cash and short-term investment balance is sufficient to fund our operations both in the short-term (i.e., the next 12 months) and in the long-term (i.e., beyond the next 12 months). In 2020 our working capital decreased because our cash and investments decreased and our 1% Notes became a current liability.

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The following table summarizes our contractual obligations as of December 31, 2020. The table provides a breakdown of when obligations become due. We provide a more detailed description of the major components of our debt in the paragraphs following the table:

Contractual Obligations Payments Due by Period(in millions)

(selected balances described below) Total Less than 1 year More than 1 year

1% Notes (principal and interest payable) $ 313.0 $ 313.0 $ —

Other obligations (principal and interest payable) 0.9 0.1 0.8

Our contractual obligations consist primarily of our convertible debt. In addition, we also have facility mortgages, facility leases, equipment financing arrangements and other obligations. Due to the uncertainty with respect to the timing of future cash outflows associated with our unrecognized tax benefits, we are unable to make reasonably reliable estimates of the period of cash settlement with the respective taxing authorities. Therefore, we have excluded our gross unrecognized tax benefits from our contractual obligations table above. We have not entered into, nor do we currently have, any off-balance sheet arrangements (as defined under SEC rules).

0.125 Percent Convertible Senior Notes and Call Spread

In December 2019, we entered into privately negotiated exchange and/or subscription agreements with certain new investors and certain holders of our existing 1% Notes to exchange $375.6 million of our 1% Notes for $439.3 million of our 0.125% Notes, and to issue $109.5 million of our 0.125% Notes. We completed this exchange to reduce our cash interest payments, increase our conversion price and extend our maturity for a large portion of our debt. Additionally, in conjunction with the December 2019 exchange, we entered into a call spread transaction, which was comprised of purchasing note hedges and selling warrants, to minimize the impact of potential economic dilution upon conversion of our 0.125% Notes by increasing the conversion price on our 0.125% Notes even further. We accounted for our call spread transactions using the Derivatives and Hedging – Contracts in Entity’s Own Equity accounting guidance contained in Topic 815. We determined that the call spread transactions meet the definition of a derivative, are indexed to our stock and meet the criteria to be classified in shareholders’ equity.

The call spread cost us $52.6 million of which $108.7 million was for the note hedge purchase offset by $56.1 million we received for selling the warrants. We increased our effective conversion price to $123.38 with the same number of underlying shares as our 0.125% Notes.

Similar to our 0.125% Notes, our note hedges are subject to adjustment. Additionally, our note hedges are exercisable upon conversion of the 0.125% Notes. The note hedges will expire upon maturity of the 0.125% Notes, or December 2024. The note hedges and warrants are separate transactions and are not part of the terms of our 0.125% Notes. The holders of the 0.125% Notes do not have any rights with respect to the note hedges and warrants.

We recorded the aggregate amount paid for the note hedges and the aggregate amount received for the warrants in additional paid-in capital in our consolidated balance sheet. See our Call Spread accounting policy in Note 1, Organization and Significant Accounting Policies, in the Notes to the Consolidated Financial Statements. We reassess our ability to continue to classify the note hedges and warrants in shareholders’ equity at each reporting period. We excluded shares under the note hedges from our calculation of diluted earnings per share as they were antidilutive. We will include the shares issuable under the warrants in our calculation of diluted earnings per share when the average market price per share of our common stock for the reporting period exceeds the strike price of the warrants.

At December 31, 2020, we had the following 0.125% Notes outstanding (amounts in millions except price per share data):

Outstanding principal balance $ 548.8

Maturity date December 2024

Interest rate 0.125 percent

Conversion price per share $ 83.28

Total shares of common stock subject to conversion 6.6

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Interest is payable semi-annually for the 0.125% Notes. The 0.125% Notes are convertible under certain conditions, at the option of the note holders. We can settle conversions of the 0.125% Notes, at our election, in cash, shares of our common stock or a combination of both. We may not redeem the 0.125% Notes prior to maturity, and no sinking fund is provided for them. Holders of the 0.125% Notes may require us to purchase some or all of their notes upon the occurrence of certain fundamental changes, as set forth in the indenture governing the 0.125% Notes, at a purchase price equal to 100 percent of the principal amount of the notes to be purchased, plus accrued and unpaid interest.

1 Percent Convertible Senior Notes

In November 2014, we completed a $500 million offering of convertible senior notes, which mature in 2021 and bear interest at 1 percent. In December 2016, we issued an additional $185.5 million of 1% Notes in exchange for the redemption of a portion of our previously outstanding 23⁄4% Notes. In December 2019, we exchanged a portion of our 1% Notes for new 0.125% Notes.

At December 31, 2020, we had the following 1% Notes outstanding (amounts in millions except price per share data):

1% Notes

Outstanding principal balance $ 309.9

Maturity date November 2021

Interest rate 1 percent

Conversion price per share $ 66.81

Total shares of common stock subject to conversion 4.6

Interest is payable semi-annually for the 1% Notes. The 1% Notes are convertible under certain conditions, at the option of the note holders. We settle conversions of the 1% Notes, at our election, in cash, shares of our common stock or a combination of both. We may not redeem the 1% Notes prior to maturity, and no sinking fund is provided for them. Holders of the 1% Notes may require us to purchase some or all of their notes upon the occurrence of certain fundamental changes, as set forth in the indenture governing the 1% Notes, at a purchase price equal to 100 percent of the principal amount of the notes to be purchased, plus accrued and unpaid interest.

Research and Development and Manufacturing Facilities

In July 2017, we purchased the building that houses our primary R&D facility for $79.4 million and our manufacturing facility for $14.0 million. We financed the purchase of these two facilities with mortgage debt of $60.4 million in total. Our primary R&D facility mortgage has an interest rate of 3.88 percent. Our manufacturing facility mortgage has an interest rate of 4.20 percent. During the first five years of both mortgages, we are only required to make interest payments. Both mortgages mature in August 2027.

Other Obligations

In addition to contractual obligations, we had outstanding purchase orders as of December 31, 2020 for the purchase of services, capital equipment and materials as part of our normal course of business.

We may enter into additional collaborations with partners which could provide for additional revenue to us and we may incur additional cash expenditures related to our obligations under any of the new agreements we may enter into. We currently intend to use our cash, cash equivalents and short-term investments to finance our activities. However, we may also pursue other financing alternatives, like issuing additional shares of our common stock, issuing debt instruments, refinancing our existing debt, or securing lines of credit. Whether we use our existing capital resources or choose to obtain financing will depend on various factors, including the future success of our business, the prevailing interest rate environment and the condition of financial markets generally.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

We are exposed to changes in interest rates primarily from our investments in certain short-term investments. We primarily invest our excess cash in highly liquid short-term investments of the U.S. Treasury and reputable financial institutions, corporations, and U.S. government agencies with strong credit ratings. We typically hold our investments for the duration of the term of the respective instrument. We do not utilize derivative financial instruments, derivative commodity instruments or other market risk sensitive instruments, positions or transactions to manage exposure to interest rate changes. Accordingly, we believe that, while the securities we hold are subject to changes in the financial standing of the issuer of such securities, we are not subject to any material risks arising from changes in interest rates, foreign currency exchange rates, commodity prices, equity prices or other market changes that affect market risk sensitive instruments.

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Item 8. Financial Statements and Supplementary Data

We filed our consolidated financial statements and supplementary data required by this item as exhibits hereto, and listed them under Item 15(a)(1) and (2), and incorporate them herein by reference.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

None.

Item 9A. Controls and Procedures

Disclosure Controls and Procedures

We maintain disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended, or Exchange Act) that are designed to ensure that information we are required to disclose in our Exchange Act reports is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms, and that such information is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure. We designed and evaluate our disclosure controls and procedures recognizing that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance and not absolute assurance of achieving the desired control objectives.

As of the end of the period covered by this report on Form 10-K, we carried out an evaluation of our disclosure controls and procedures under the supervision of, and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer. Based on our evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective as of December 31, 2020.

Management’s Report on Internal Control over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as defined in Exchange Act Rules 13a-15(f). Our internal control over financial reporting is a process designed under the supervision of our Chief Executive Officer and Chief Financial Officer to provide reasonable assurance regarding the reliability of financial reporting and the preparation of our financial statements for external purposes in accordance with U.S. generally accepted accounting principles.

As of December 31, 2020, we assessed the effectiveness of our internal control over financial reporting based on the criteria for effective internal control over financial reporting under the 2013 “Internal Control—Integrated Framework,” issued by the Committee of Sponsoring Organizations, or COSO, of the Treadway Commission, under the supervision of, and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer. Based on that assessment, our management concluded that we maintained effective internal control over financial reporting as of December 31, 2020.

Ernst & Young LLP, an independent registered public accounting firm, audited the effectiveness of our internal control over financial reporting as of December 31, 2020, as stated in their attestation report, which is included elsewhere herein.

Changes in Internal Control over Financial Reporting

The above assessment did not identify any change in our internal control over financial reporting that occurred during our latest fiscal quarter and that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

78

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and Board of Directors of Ionis Pharmaceuticals, Inc.

Opinion on Internal Control over Financial Reporting

We have audited Ionis Pharmaceuticals, Inc.’s internal control over financial reporting as of December 31, 2020, based on criteria established in Internal Control — Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, Ionis Pharmaceuticals, Inc. (the Company) maintained, in all material respects, effective internal control over financial reporting as of December 31, 2020, based on the COSO criteria.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2020 and 2019, and the related consolidated statements of operations, comprehensive income (loss), stockholders’ equity, and cash flows for each of the three years in the period ended December 31, 2020, and the related notes and our report dated February 24, 2021 expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ernst & Young LLP

San Diego, California

February 24, 2021

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Item 9B. Other Information

Not applicable.

PART III

Item 10. Directors, Executive Officers and Corporate Governance

We incorporate by reference the information required by this Item with respect to directors and the Audit Committee from the information under the caption “ELECTION OF DIRECTORS,” including in particular the information under “Nominating, Governance and Review Committee” and “Audit Committee,” contained in our definitive Proxy Statement, which we will file with the Securities and Exchange Commission within 120 days after the end of the fiscal year ended December 31, 2020, or the Proxy Statement.

We incorporate by reference the required information concerning our Code of Ethics from the information under the caption “Code of Ethics and Business Conduct” contained in the Proxy Statement. Our Code of Ethics and Business Conduct is posted on our website at www.ionispharma.com(1). We intend to disclose future amendments to, or waivers from, our Code of Ethics and Business Conduct on our website.

________________

Delinquent Section 16(a) Reports

Item 1, Part I of this Report contains information concerning our executive officers. We incorporate by reference the information required by this Item concerning compliance with Section 16(a) of the Exchange Act from the information under the caption “Delinquent Section 16(a) Reports” contained in the Proxy Statement.

Item 11. Executive Compensation

We incorporate by reference the information required by this item to the information under the caption “EXECUTIVE COMPENSATION,” “Compensation Committee Interlocks and Insider Participation” and “COMPENSATION COMMITTEE REPORT” contained in the Proxy Statement.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

We incorporate by reference the information required by this item to the information under the captions “SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT” contained in the Proxy Statement.

Securities Authorized for Issuance under Equity Compensation Plans

The following table sets forth information regarding outstanding options and shares reserved for future issuance under our equity compensation plans as of December 31, 2020.

________________

For additional details about our equity compensation plans, including a description of each plan, see Note 4, Stockholders’ Equity, in the Notes to the Consolidated Financial Statements.

80

Item 13. Certain Relationships and Related Transactions, and Director Independence

We incorporate by reference the information required by this item to the information under the captions “Independence of the Board of Directors” and “Certain Relationships and Related Transactions” contained in the Proxy Statement.

Item 14. Principal Accounting Fees and Services

We incorporate by reference the information required by this item to the information under the caption “Ratification of Selection of Independent Auditors” contained in the Proxy Statement.

PART IV

Item 15. Exhibits, Financial Statement Schedules

(a)(1) Index to Financial Statements

We submitted the consolidated financial statements required by this item in a separate section beginning on page F-1 of this Report.

(a)(2) Index to Financial Statement Schedules

We omitted these schedules because they are not required, or are not applicable, or the required information is shown in the consolidated financial statements or notes thereto.

(a)(3) Index to Exhibits

81

INDEX TO EXHIBITS

Exhibit Number Description of Document

82

83

84

85

86

87

88

21.1 List of Subsidiaries for the Registrant.

23.1 Consent of Independent Registered Public Accounting Firm.

89

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report on Form 10-K to be signed on its behalf by the undersigned, thereunto duly authorized on the 24th day of February, 2021.

IONIS PHARMACEUTICALS, INC.

By: /s/ BRETT P. MONIA

Brett P. Monia., Ph.D.

Chief Executive Officer (Principal executive officer)

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Brett P. Monia and Elizabeth L. Hougen, or any of them, his or her attorney-in-fact, each with the power of substitution, for him or her in any and all capacities, to sign any amendments to this Report, and to file the same, with exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, hereby ratifying and confirming all that each of said attorneys-in-fact, or his or her substitute or substitutes, may do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the Registrant and in the capacities and on the dates indicated.

Signatures Title Date

/s/ BRETT P. MONIA Director and Chief Executive Officer February 24, 2021

Brett P. MONIA, Ph.D. (Principal executive officer)

Elizabeth L. Hougen (Principal financial and accounting officer)

/s/ STANLEY T. CROOKE Executive Chairman of the Board February 24, 2021

Stanley T. Crooke, M.D., Ph.D.

/s/ B. LYNNE PARSHALL Director and Senior Strategic Advisor February 24, 2021

B. Lynne Parshall, J.D.

/s/ SPENCER R. BERTHELSEN Director February 24, 2021

Spencer R. Berthelsen, M.D.

/s/ BREAUX CASTLEMAN Director February 24, 2021

Breaux Castleman

/s/ MICHAEL HAYDEN Director February 24, 2021

Michael Hayden, CM OBC MB ChB PhD FRCP(C) FRSC

/s/ JOAN E. HERMAN Director February 24, 2021

Joan E. Herman

/s/ JOSEPH KLEIN Director February 24, 2021

Joseph Klein, III

/s/ JOSEPH LOSCALZO Director February 24, 2021

Joseph Loscalzo, M.D., Ph.D.

/s/ FREDERICK T. MUTO Director February 24, 2021

Frederick T. Muto, Esq.

/s/ PETER N. REIKES Director February 24, 2021

Peter N. Reikes

/s/ JOSEPH H. WENDER Director February 24, 2021

Joseph H. Wender

90

IONIS PHARMACEUTICALS, INC.

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Page

Report of Independent Registered Public Accounting Firm F-2

Consolidated Balance Sheets at December 31, 2020 and 2019 F-3

Notes to Consolidated Financial Statements F-9

F-1

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and Board of Directors of Ionis Pharmaceuticals, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Ionis Pharmaceuticals, Inc. (the “Company“) as of December 31, 2020 and 2019, the related consolidated statements of operations, comprehensive income (loss), stockholders’ equity, and cash flows, for each of the three years in the period ended December 31, 2020 and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2020 and 2019, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2020, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2020, based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated February 24, 2021 expressed an unqualified opinion thereon.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures include examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the account or disclosure to which it relates.