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

The following discussion and analysis is meant to provide material information relevant to an assessment of the financial condition and results of operations of our company, including an evaluation of the amounts and certainty of cash flows from operations and from outside resources, so as to allow investors to better view our company from management’s perspective. The following discussion of our financial condition and results of operations should be read in conjunction with our financial statements and the notes to those financial statements appearing elsewhere in this Annual Report on Form 10-K. This discussion contains forward-looking statements that involve significant risks and uncertainties. As a result of many factors, such as those set forth in Part I, Item 1A. Risk Factors, of this Annual Report on Form 10-K, our actual results may differ materially from those anticipated in these forward-looking statements.

We are a global biopharmaceutical company focused on the discovery, development and commercialization of clinically differentiated medicines that provide benefits to patients with rare disorders. Our ability to innovate to identify new therapies and to globally commercialize products is the foundation that drives investment in a robust and diversified pipeline of transformative medicines. Our mission is to provide access to best-in-class treatments for patients who have little to no treatment options. Our strategy is to leverage our strong scientific and clinical expertise and global commercial infrastructure to bring therapies to patients. We believe that this allows us to maximize value for all of our stakeholders. We have a diversified therapeutic portfolio that includes several commercial products and product candidates in various stages of development, including clinical, pre-clinical and research and discovery stages, focused on the development of new treatments for multiple therapeutic areas for rare diseases relating to neurology and metabolism.

We have two products, TranslarnaTM (ataluren) and Emflaza® (deflazacort), for the treatment of Duchenne muscular dystrophy, or DMD, a rare, life threatening disorder. Translarna currently has conditional marketing authorization in the European Economic Area, or EEA, for the treatment of nonsense mutation Duchenne muscular dystrophy, or nmDMD, in ambulatory patients aged two years and older. Translarna also has marketing authorization in Russia for the treatment of

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nmDMD in patients aged two years and older, and in Brazil for the treatment of nmDMD in ambulatory patients two years and older and for continued treatment of patients that become non-ambulatory, as well as in various other countries. During the year ended December 31, 2023, we recognized $355.8 million in sales of Translarna. We hold worldwide commercialization rights to Translarna for all indications in all territories. Emflaza is approved in the United States for the treatment of DMD in patients two years and older. During the year ended December 31, 2023, Emflaza achieved net sales of $255.1 million.

Our marketing authorization for Translarna in the EEA is subject to annual review and renewal by the European Commission, or EC, following reassessment by the European Medicines Agency, or EMA, of the benefit-risk balance of the authorization, which we refer to as the annual EMA reassessment. In September 2022, we submitted a Type II variation to the EMA to support conversion of the conditional marketing authorization for Translarna to a standard marketing authorization, which included a report on the placebo-controlled trial of Study 041 and data from the open-label extension as further described below. Study 041 was an 18-month, placebo-controlled trial, followed by an 18-month open-label extension of Translarna in the treatment of ambulatory patients with nmDMD aged five years or older. In February 2023, we also submitted an annual marketing authorization renewal request to the EMA. In September 2023, the Committee for Medicinal Products for Human Use, or CHMP, gave a negative opinion on the conversion of the conditional marketing authorization to full marketing authorization of Translarna for the treatment of nmDMD and a negative opinion on the renewal of the existing conditional marketing authorization of Translarna for the treatment of nmDMD. On January 25, 2024, the CHMP issued a negative opinion for the renewal of the conditional marketing authorization following a re-examination procedure. In accordance with EMA regulations, the EC has 67 days to adopt the opinion. If the EC adopts the negative opinion, Translarna would no longer have marketing authorization in the member states of the EEA. We are exploring other potential mechanisms in which we may provide Translarna to nmDMD patients in the EEA if the negative opinion is adopted by the EC.

Each country, including each member state of the EEA, has its own pricing and reimbursement regulations. In order to commence commercial sale of product pursuant to our Translarna marketing authorization in any particular country in the EEA, we must finalize pricing and reimbursement negotiations with the applicable government body in such country. As a result, our commercial launch will continue to be on a country-by-country basis. We also have made, and expect to continue to make, product available under early access programs, or EAP programs, or similar styled programs both in countries in the EEA and other territories. Our ability to negotiate, secure and maintain reimbursement for product under commercial and EAP programs can be subject to challenge in any particular country and can also be affected by political, economic and regulatory developments in such country.

There is substantial risk that if the EC adopts the CHMP’s negative opinion, or we are otherwise unable to renew our EEA marketing authorization during any annual renewal cycle, or we are unable to identify other potential mechanisms in which we may provide Translarna to nmDMD patients in the EEA should the EC adopts the CHMP’s negative opinion or our product label is materially restricted, we would lose all, or a significant portion of, our ability to generate revenue from sales of Translarna in the EEA and other territories. For more information regarding the risks associated with the a potential EC adoption of the CHMP’s negative opinion on Translarna’s marketing authorization, see Item 1A. Risk Factors,“We may be unable to continue to commercialize Translarna for nonsense mutation Duchenne muscular dystrophy in the European Economic Area if the European Commission adopts the negative opinion issued by the Committee for Medicinal Products for Human Use of the European Medicines Agency for the renewal of the existing conditional authorization for Translarna.”

Translarna is an investigational new drug in the United States. During the first quarter of 2017, we filed a New Drug Application, or NDA, for Translarna for the treatment of nmDMD over protest with the United States Food and Drug Administration, or FDA. In October 2017, the Office of Drug Evaluation I of the FDA issued a Complete Response Letter for the NDA, stating that it was unable to approve the application in its current form. In response, we filed a formal dispute resolution request with the Office of New Drugs of the FDA. In February 2018, the Office of New Drugs of the FDA denied our appeal of the Complete Response Letter. In its response, the Office of New Drugs recommended a possible path forward for the ataluren NDA submission based on the accelerated approval pathway. This would involve a re-submission of an NDA containing the current data on effectiveness of ataluren with new data to be generated on dystrophin production in nmDMD patients’ muscles. We followed the FDA’s recommendation and collected, using newer technologies via procedures and methods that we designed, such dystrophin data in a new study, Study 045, and announced

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the results of Study 045 in February 2021. Study 045 did not meet its pre-specified primary endpoint. In June 2022, we announced top-line results from the placebo-controlled trial of Study 041. Following this announcement, we submitted a meeting request to the FDA to gain clarity on the regulatory pathway for a potential re-submission of an NDA for Translarna. The FDA provided initial written feedback that Study 041 does not provide substantial evidence of effectiveness to support NDA re-submission. We held a Type C meeting with the FDA in the fourth quarter of 2023 to discuss the totality of Translarna data. Based on this discussion, the FDA suggested we request a pre-submission Type C meeting to discuss the specific contents of an NDA resubmission based on results from Study 041 and from our international drug registry study for nmDMD patients receiving Translarna. This meeting is scheduled for March 2024.

We have previously relied on Emflaza’s seven-year marketing exclusivity period in the United States for its approved indications under the provisions of the Orphan Drug Act of 1983, or the Orphan Drug Act, when commercializing Emflaza. Emflaza’s seven-year period of orphan drug exclusivity related to the treatment of DMD in patients five years and older expired in February 2024. We expect the expiration of this orphan drug exclusivity to have a significant negative impact on Emflaza net product revenue. Emflaza’s orphan drug exclusivity related to the treatment of DMD in patients two years of age to less than five expires in June 2026.

Upstaza is a gene therapy for the treatment of Aromatic L Amino Decarboxylase, or AADC, deficiency, a rare central nervous system, or CNS, disorder arising from reductions in the enzyme AADC that results from mutations in the dopa decarboxylase gene. In July 2022, the EC approved Upstaza for the treatment of AADC deficiency for patients 18 months and older within the EEA. In November 2022, the Medicines and Healthcare products Regulatory Agency approved Upstaza for the treatment of AADC deficiency for patients 18 months and older within the United Kingdom. We are also preparing a biologics license application, or BLA, for Upstaza for the treatment of AADC deficiency in the United States. In October 2022, we held a Type C meeting with the FDA to discuss the details of a potential submission package for Upstaza. At that meeting, the FDA asked for additional bioanalytical data in support of comparability between the drug product used in the clinical studies and the commercial drug product. We completed these analyses and provided the results to the FDA for review. The FDA stated that the data that we provided were still not sufficient. However, the FDA also said that the available data from the ongoing clinical study in the United States assessing the safety of the drug delivery cannula for Upstaza could be used to support a BLA for accelerated approval based on biomarker data demonstrating a treatment-related increase in de novo dopamine production. At the FDA’s suggestion, we held a pre-BLA meeting in December 2023. We expect to submit a BLA to the FDA for Upstaza for the treatment of AADC deficiency in March 2024.

We hold the rights for the commercialization of Tegsedi and Waylivra for the treatment of rare diseases in countries in Latin America and the Caribbean pursuant to a Collaboration and License Agreement, or the Tegsedi-Waylivra Agreement, dated August 1, 2018, by and between us and Akcea Therapeutics, Inc., or Akcea, a subsidiary of Ionis Pharmaceuticals, Inc. Tegsedi has received marketing authorization in the United States, European Union, or EU, and Brazil for the treatment of stage 1 or stage 2 polyneuropathy in adult patients with hereditary transthyretin amyloidosis, or hATTR amyloidosis. In August 2021, ANVISA, the Brazilian health regulatory authority, approved Waylivra as the first treatment for familial chylomicronemia syndrome, or FCS, in Brazil. In December 2022, ANVISA approved Waylivra for the treatment of familial partial lipodystrophy, or FPL. Waylivra has also received marketing authorization in the EU for the treatment of FCS.

We also have a spinal muscular atrophy, or SMA, collaboration with F. Hoffman La Roche Ltd. and Hoffman La Roche inc., which we refer to collectively as Roche, and the Spinal Muscular Atrophy Foundation, or SMA Foundation. The SMA program has one approved product, Evrysdi® (risdiplam), which was approved by the FDA in August 2020 for the treatment of SMA in adults and children two months and older and by the EC in March 2021 for the treatment of 5q SMA in patients two months and older with a clinical diagnosis of SMA Type 1, Type 2 or Type 3 or with one to four SMN2 copies. Evrysdi has also received marketing authorization for the treatment of SMA in over 100 countries. In May 2022, the FDA approved a label expansion for Evrysdi to include infants under two months old with SMA. In August 2023, the EC approved an extension of the Evrysdi marketing authorization to include infants under two months old in the EU.

One of our most advanced clinical stage molecules is sepiapterin. Sepiapterin is a precursor to intracellular tetrahydrobiopterin, which is a critical enzymatic cofactor involved in metabolism and synthesis of numerous metabolic

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products, for orphan diseases. In May 2023, we announced that the primary endpoint was achieved in our registration-directed Phase 3 trial for sepiapterin for phenylketonuria, or PKU. The primary endpoint of the study was the achievement of statistically-significant reduction in blood Phe level. The primary analysis population included those patients who have a greater than 30% reduction in blood Phe levels during the Part 1 run-in phase of the trial. Sepiapterin demonstrated Phe level reduction of approximately 63% in the overall primary analysis population and Phe level reduction of approximately 69% in the subset for classical PKU patients. Additionally, sepiapterin was well tolerated with no serious adverse events. Following the placebo-controlled study, patients were eligible to enroll in a long-term open-label study, which is still ongoing and will evaluate long-term safety, durability and Phe tolerance. We expect to submit a marketing authorization application, or MAA, to the EMA for sepiapterin for the treatment of PKU in the EEA in March 2024. Additionally, we participated in a pre-NDA meeting with the FDA in the third quarter of 2023. At that meeting, the FDA stated that the sepiapterin clinical safety and efficacy data supported NDA submission for the treatment of pediatric and adult PKU patients. However, the FDA has requested that we complete a 26-week nonclinical mouse study to assess sepiapterin carcinogenicity potential prior to NDA submission. This nonclinical study was not initially required when we acquired sepiapterin, as the NDA submission was planned under the Section 505(b)(2) pathway. Given that sepiapterin is a novel therapy with distinct pharmacology, biodistribution, mechanism of action and differentiated efficacy, we subsequently decided to make the NDA submission under the Section 505(b)(1) pathway, which requires the 26-week study, which is considered a required NDA component needed to inform labeling and is typically completed prior to submission. Based on the timing to complete this study, we expect to submit an NDA to the FDA for sepiapterin for the treatment of PKU no later than the third quarter of 2024 and we intend to discuss with the FDA the potential for an earlier submission if we are permitted to submit the 26-week mouse study report during the NDA review process.

In addition to our SMA program, our splicing platform also includes PTC518, which is being developed for the treatment of Huntington’s disease, or HD. We announced the results from our Phase 1 study of PTC518 in healthy volunteers in September 2021 demonstrating dose-dependent lowering of huntingtin messenger ribonucleic acid and protein levels, that PTC518 efficiently crosses blood brain barrier at significant levels and that PTC518 was well tolerated. We initiated a Phase 2 study of PTC518 for the treatment of HD in the first quarter of 2022, which consists of an initial 12-week placebo-controlled phase focused on safety, pharmacology and pharmacodynamic effects followed by a nine-month placebo-controlled phase focused on PTC518 biomarker effect. In June 2023, we announced interim data from the 12-week placebo-controlled phase. The study demonstrated dose-dependent lowering of Huntingtin, or HTT, protein levels in peripheral blood cells, reaching an approximate mean 30% reduction in mutant HTT levels at the 10mg dose level. In addition, PTC518 exposure in the cerebrospinal fluid was consistent with or higher than plasma unbound drug levels. Furthermore, PTC518 was well tolerated with no treatment-related serious adverse events. The Phase 2 study is actively ongoing outside the United States, while it has been paused within the United States as the FDA requested additional data to allow the Phase 2 study to proceed. We expect to provide 12-month interim data from the Phase 2 study of PTC518 for the treatment of HD in the second quarter of 2024. We expect to submit a safety data update to the FDA in the second quarter of 2024 to support lifting of the partial clinical hold on the program.

Our ferroptosis and inflammation platform consists of small molecule compounds that target oxidoreductase enzymes that regulate oxidative stress and inflammatory pathways central to the pathology of a number of CNS diseases. The two most advanced molecules in our ferroptosis and inflammation platform are vatiquinone and utreloxastat. We announced topline results from a registration-directed Phase 3 trial of vatiquinone in children and young adults with Friedreich ataxia, called MOVE-FA, in May 2023. While the study did not meet its primary endpoint of statistically significant change in modified Friedreich Ataxia Rating Scale, or mFARS, score at 72 weeks in the primary analysis population, vatiquinone treatment did demonstrate significant benefit on key disease subscales and secondary endpoints. In addition, in the population of subjects that completed the study protocol, significance was reached in the mFARS endpoint and several secondary endpoints, including the upright stability subscale. Furthermore, vatiquinone was well tolerated. In the first quarter of 2024, we met with the FDA, who expressed willingness to review an NDA for vatiquinone for the treatment of Friedreich ataxia based on the MOVE-FA trial as well as data from the ongoing open label extension study following the MOVE-FA trial, potentially allowing for the submission of an NDA in late 2024. In the first quarter of 2024, we also received scientific advice from the EMA on the MOVE-FA trial results, in which the EMA stated that the MOVE-FA data would likely not be sufficient for conditional authorization. In the third quarter of 2021, we completed a Phase 1 trial in healthy volunteers to evaluate the safety and pharmacology of utreloxastat. Utreloxastat was found to be well-tolerated with no reported serious adverse events while demonstrating predictable pharmacology. We initiated a Phase 2 registration

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directed trial of utreloxastat for amyotrophic lateral sclerosis, or ALS, in the first quarter of 2022. We expect topline results from this trial in the fourth quarter of 2024.

In addition, we have a pipeline of product candidates and discovery programs that are in early clinical, pre-clinical and research and development stages focused on the development of new treatments for multiple therapeutic areas for rare diseases.

In May 2023 and September 2023, we announced strategic pipeline prioritizations following reviews of our portfolio. In connection with the strategic pipeline prioritizations, we reduced our workforce by 32%, which primarily affected employees in the United States, including those employees involved in early-stage research and gene therapy manufacturing and associated selling, general and administrative functions. We substantially completed the reduction in workforce in January 2024. We also decided to discontinue our preclinical and early research programs for our gene therapy platform, which included programs for Friedreich ataxia and Angelman syndrome, as well as our oncology platform, which included programs for unesbulin for the treatment of diffuse intrinsic pontine glioma and leiomyosarcoma.

Overview—Funding

The success of our products and any other product candidates we may develop, depends largely on obtaining and maintaining reimbursement from governments and third-party insurers. During 2023, our revenues were primarily generated from sales of Translarna for the treatment of nmDMD in countries where we were able to obtain acceptable commercial pricing and reimbursement terms and in select countries where we are permitted to distribute Translarna under our EAP programs or through similar styled programs, and from sales of Emflaza for the treatment of DMD in the United States. We also generated revenue from sales of Upstaza for the treatment of AADC deficiency in the EEA and have recognized revenue associated with milestone and royalty payments from Roche pursuant to a License and Collaboration Agreement, or the SMA License Agreement, by and among us, Roche and, for the limited purposes set forth therein, the SMA Foundation, under our SMA program.

See “Item 1. Business—Commercial Matters—Market Access Considerations” for additional information and “Item 1A. Risk Factors—Commercialization of Translarna and Upstaza has been in, and is expected to continue to take place in, countries that tend to impose strict price controls, which may adversely affect our revenues. Failure to obtain and maintain acceptable pricing and reimbursement terms for Translarna for the treatment of nmDMD or Upstaza for the treatment of AADC deficiency in the EEA and other countries where Translarna is available would delay or prevent us from marketing our product in such regions, which would adversely affect our business, results of operations, and financial condition.”

In August 2019, we entered into an At the Market Offering Sales Agreement, or the Sales Agreement, with Cantor Fitzgerald and RBC Capital Markets, LLC, or together, the Sales Agents, pursuant to which, we may offer and sell shares of our common stock, having an aggregate offering price of up to $125.0 million from time to time through the Sales Agents by any method that is deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended, or the Securities Act. We did not issue or sell any shares of common stock pursuant to the Sales Agreement during the years ending December 31, 2023, 2022, and 2021. The remaining shares of our common stock available to be issued and sold, under the Sales Agreement, have an aggregate offering price of up to $93.0 million as of December 31, 2023.

In September 2019, we issued $287.5 million aggregate principal amount of 1.50% convertible senior notes due September 15, 2026, or the 2026 Convertible Notes, which included an option to purchase up to an additional $37.5 million in aggregate principal amount of the 2026 Convertible Notes, which was exercised in full by the initial purchasers. We received net proceeds of $279.3 million after deducting the initial purchasers’ discounts and commissions and the offering expenses payable by us. See “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and capital resources—Sources of Liquidity” for additional information.

In July 2020, we entered into a Royalty Purchase Agreement, or the Original Royalty Purchase Agreement, with RPI Intermediate Finance Trust, or RPI, and, for the limited purposes set forth in the agreement, Royalty Pharma plc. Pursuant to the Original Royalty Purchase Agreement, we sold to RPI 42.933%, or the Original Assigned Royalty Rights, of the

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Royalty (as defined below) for $650.0 million. At that time, we retained a 57.067% interest in the Royalty and all economic rights to receive the remaining potential regulatory and sales milestone payments under the SMA License Agreement.

In June 2021, we filed a Certificate of Amendment to our Restated Certificate of Incorporation, which increased the number of authorized shares of our common stock from 125,000,000 to 250,000,000 shares.

In October 2022, we entered into the Credit Agreement, dated October 27, 2022, by and among us and certain of our subsidiaries from time to time party thereto, as guarantors, or, collectively with us, the Loan Parties, funds and other affiliated entities advised or managed by Blackstone Life Sciences and Blackstone Credit, or collectively, Blackstone, as lenders, together with their permitted assignees, the Lenders, and Wilmington Trust, National Association, as the administrative agent for the Lenders, or the Blackstone Credit Agreement. The Blackstone Credit Agreement provided for fundings of up to $950.0 million consisting of a committed loan facility consisting of a senior secured term loan facility funded on October 27, 2022, or the Closing Date, in the aggregate principal amount of $300.0 million, and a delayed draw term loan facility of up to $150.0 million to be funded at our request within 18 months of the Closing Date subject to specified conditions, and further contemplating the potential for up to $500.0 million of additional financing, to the extent that we requested such additional financing and subject to the Lenders’ agreement to provide such additional financing and to mutual agreement on terms. In October 2023, we terminated the Blackstone Credit Agreement. In connection with the termination of the Blackstone Credit Agreement, we repaid outstanding principal of $300.0 million, accrued interest of $2.1 million, an additional $82.0 million in prepayment premiums, exit fees, and creditor expenses, and $0.2 million in legal fees. We recorded a loss on the extinguishment of debt of $92.7 million which is included on the statement of operations for the period ended December 31, 2023. The loss on extinguishment of debt consisted of $82.0 million in prepayment premiums, exit fees, and creditor expenses and debt issuance costs of $10.7 million. All liens and security interests securing the loans made pursuant to the Blackstone Credit Agreement were released upon termination.

In October 2023, we entered into an Amended and Restated Royalty Purchase Agreement, or the A&R Royalty Purchase Agreement, with Royalty Pharma Investments 2019 ICAV, or Royalty Pharma, and, for the limited purposes set forth in the agreement, Royalty Pharma plc which amends and restates in its entirety the Original Royalty Purchase Agreement. Pursuant to the A&R Royalty Purchase Agreement, we have sold or agreed to sell to Royalty Pharma certain portions of our remaining retained right, title and interest in and to our right to receive sales-based royalty payments, or the Royalty, on worldwide net sales of Evrysdi and any other product developed pursuant to the SMA License Agreement under the SMA program (all such Royalty rights retained by us, are referred to as the Retained Royalty Rights, and all such Royalty rights that are sold to Royalty Pharma pursuant to the A&R Royalty Purchase Agreement, are referred to as the A&R Assigned Royalty Rights). At closing, Royalty Pharma paid us $1.0 billion in cash consideration for 38.0447% of our Retained Royalty Rights (which is in addition to the 42.9330% assigned to Royalty Pharma in connection with the Original Royalty Purchase Agreement and referred to as the Original Assigned Royalty Rights, for a total of 80.9777% of the total Royalty) until such time as Royalty Pharma has received payments in respect of the Original Assigned Royalty Rights equal to $1.3 billion in the aggregate, and thereafter 66.6667% of the total Royalty. See “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and capital resources—Sources of Liquidity” for additional information.

We have financed our operations to date primarily through the private offerings of convertible senior notes, public and “at the market offerings” of common stock, proceeds from royalty purchase agreements, net proceeds from our borrowings under our credit agreement with Blackstone, private placements of our convertible preferred stock and common stock, collaborations, bank and institutional lender debt, other convertible debt, grant funding and clinical trial support from governmental and philanthropic organizations and patient advocacy groups in the disease area addressed by our product candidates. We have relied on revenue generated from net sales of Translarna for the treatment of nmDMD in territories outside of the United States since 2014, Emflaza for the treatment of DMD in the United States since 2017 and Upstaza for the treatment of AADC deficiency in the EEA since 2022. We have also relied on revenue associated with milestone and royalty payments from Roche pursuant to the SMA License Agreement, under our SMA program.

As of December 31, 2023, we had an accumulated deficit of $3,283.6 million. We had a net loss of $626.6 million, $559.0 million, and $523.9 million for the fiscal years ended December 31, 2023, 2022, and 2021, respectively.

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We anticipate that we will continue to incur significant expenses in connection with our commercialization efforts in the United States, the EEA, Latin America and other territories, including expenses related to our commercial infrastructure and corresponding sales and marketing, legal and regulatory, and distribution and manufacturing undertakings as well as administrative and employee-based expenses. In addition to the foregoing, we expect to continue to incur significant costs in connection with ongoing, planned and potential future clinical trials and studies for sepiapterin and our splicing and ferroptosis and inflammation programs as well as studies in our products for maintaining authorizations, label extensions and additional indications. We continue to seek marketing authorization for Translarna for the treatment of nmDMD in territories that we do not currently have marketing authorization in and we are exploring other potential mechanisms in which we may provide Translarna to nmDMD patients in the EEA if the EC adopts the CHMP’s negative opinion for Translarna following a re-examination procedure. We anticipate submitting a BLA to the FDA for Upstaza for the treatment of AADC deficiency in the United States in March 2024. We also expect to submit an MAA to the EMA for sepiapterin for the treatment of PKU in March 2024 and we expect to submit an NDA to the FDA for sepiapterin for the treatment of PKU no later than the third quarter of 2024. These efforts may significantly impact the timing and extent of our commercialization and manufacturing expenses.

We may seek to expand and diversify our product pipeline through opportunistically in-licensing or acquiring the rights to products, product candidates or technologies and we may incur expenses, including with respect to transaction costs, subsequent development costs or any upfront, milestone or other payments or other financial obligations associated with any such transaction, which would increase our future capital requirements.

With respect to our outstanding 2026 Convertible Notes, cash interest payments are payable on a semi-annual basis in arrears, which will require total funding of $4.3 million annually. Borrowings under the Blackstone Credit Agreement, which was terminated in October 2023, bore interest at a variable rate equal to, at our option, either an adjusted Term SOFR rate plus seven and a quarter percent (7.25%) or the Base Rate plus six and a quarter percent (6.25%), subject to a floor of one percent (1%) and two percent (2%) with respect to Term SOFR rate and Base Rate (each as defined in the Blackstone Credit Agreement), respectively.

In February 2023, we completed enrollment of our Phase 3 placebo-controlled clinical trial for sepiapterin for PKU. In connection with this event and pursuant to the Censa Merger Agreement, we paid a $30.0 million development milestone to the former Censa securityholders during the year ended December 31, 2023. We elected to pay this milestone in the form of shares of our common stock, less certain cash payments in accordance with the Censa Merger Agreement. Pursuant to such election, we issued 657,462 shares of our common stock and paid $0.4 million to the former Censa securityholders.

We expect to make additional payments to the former Censa securityholders of $65.0 million in the aggregate in cash upon the potential achievement in 2024 of certain regulatory milestones relating to sepiapterin. Furthermore, we expect to pay the former equityholders of Agilis Biotherapeutics, Inc., or Agilis, $20.0 million in development milestone payments upon the acceptance for filing by the FDA of a BLA for Upstaza for the treatment of AADC deficiency and $4.5 million in regulatory milestone payments upon the approval of the BLA from the FDA pursuant to the Agreement and Plan of Merger, dated as of July 19, 2018, or the Agilis Merger Agreement, by and among us, Agility Merger Sub, Inc., a Delaware corporation and our wholly owned, indirect subsidiary, Agilis and, solely in its capacity as the representative, agent and attorney-in-fact of the equityholders of Agilis, Shareholder Representative Services LLC. We anticipate submitting a BLA to the FDA for Upstaza for the treatment of AADC deficiency in the United States in March 2024.

We have never been profitable and we will need to generate significant revenues to achieve and sustain profitability, and we may never do so. Accordingly, we may need to obtain substantial additional funding in connection with our continuing operations. Adequate additional financing may not be available to us on acceptable terms, or at all. If we are unable to raise capital when needed or on attractive terms, we could be forced to delay, reduce or eliminate our research and development programs or our commercialization efforts.

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Financial operations overview

Revenues

To date, our net product revenues have consisted primarily of sales of Translarna for the treatment of nmDMD in territories outside of the United States, and sales of Emflaza for the treatment of DMD in the United States. Our process for recognizing revenue is described below under “Critical accounting policies and significant judgments and estimates—Revenue recognition”.

Roche and the SMA Foundation Collaboration. In November 2011, we entered into the SMA License Agreement pursuant to which we are collaborating with Roche and the SMA Foundation to further develop and commercialize compounds identified under our SMA program with the SMA Foundation. The research component of this agreement terminated effective December 31, 2014. We are eligible to receive additional payments from Roche if specified events are achieved with respect to each licensed product, including up to $135.0 million in research and development event milestones, up to $325.0 million in sales milestones upon achievement of specified sales events, and up to double digit royalties on worldwide annual net sales of a commercial product. As of December 31, 2023, we had recognized a total of $310.0 million in milestone payments and $341.8 million royalties on net sales pursuant to the SMA License Agreement. As of December 31, 2023, there are no remaining research and development event milestones that we can receive. The remaining potential sales milestones as of December 31, 2023 are $150.0 million upon achievement of certain sales events.

In July 2020, we entered into the Original Royalty Purchase Agreement. Pursuant to the Original Royalty Purchase Agreement, we sold to Royalty Pharma the Original Assigned Royalty Rights of the Royalty for $650.0 million. At that time, we retained a 57.067% interest in the Royalty and all economic rights to receive the remaining potential regulatory and sales milestone payments under the SMA License Agreement.

Research and development expense

Research and development expenses consist of the costs associated with our research activities, as well as the costs associated with our drug discovery efforts, conducting preclinical studies and clinical trials, manufacturing development efforts and activities related to regulatory filings. Our research and development expenses consist of:

We use our employee and infrastructure resources across multiple research projects, including our drug development programs. We track expenses related to our clinical programs and certain preclinical programs on a per project basis.

We expect our research and development expenses to fluctuate in connection with our ongoing activities, particularly in connection with our activities for sepiapterin and our splicing and ferroptosis and inflammation programs and performance of any post-marketing requirements imposed by regulatory agencies with respect to our products. The timing and amount of these expenses will depend upon the outcome of our ongoing clinical trials and the costs associated with our planned clinical trials. The timing and amount of these expenses will also depend on the costs associated with potential

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future clinical trials of our products or product candidates and the related expansion of our research and development organization, regulatory requirements, advancement of our preclinical programs, and product and product candidate manufacturing costs. In 2023, as part of our strategic pipeline prioritizations, we decided to discontinue our preclinical and early research programs for our gene therapy and oncology platforms, reducing research and development expenses in these areas.

The following table provides research and development expense for our most advanced principal product development programs, for the years ended December 31, 2023, 2022, and 2021.

Year ended

December 31,

(in thousands)

The successful development of our products and product candidates is highly uncertain. This is due to the numerous risks and uncertainties associated with developing drugs, including the uncertainty of:

● clinical trial results;

● the terms and timing of regulatory approvals; and

A change in the outcome of any of these variables with respect to the development of our products or product candidates could mean a significant change in the costs and timing associated with the development of those products or product candidates. For example, if the EMA or FDA or other regulatory authority were to require us to conduct clinical trials beyond those which we currently anticipate will be required for the completion of clinical development of any of our products or product candidates or if we experience significant delays in enrollment in any of our clinical trials, we could be required to expend significant additional financial resources and time on the completion of clinical development.

Selling, general and administrative expense

Selling, general and administrative expenses consist primarily of salaries and other related costs for personnel, including share-based compensation expenses, in our executive, legal, business development, commercial, finance, accounting, information technology and human resource functions. Other selling, general and administrative expenses include facility-related costs not otherwise included in research and development expense; advertising and promotional expenses; costs associated with industry and trade shows; and professional fees for legal services, including patent-related expenses, accounting services and miscellaneous selling costs.

We expect that we will continue to incur significant selling, general and administrative expenses in future periods in connection with our continued efforts to commercialize our products, including increased payroll, expanded infrastructure, commercial operations, increased consulting, legal, accounting and investor relations expenses.

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Interest expense, net

Interest expense, net consists of interest expense from the liability for the sale of future royalties related to the Original Royalty Purchase Agreement, the A&R Royalty Purchase Agreement, the 2026 Convertible Notes outstanding, the Blackstone Credit Agreement that we repaid and terminated in October 2023, the 3.00% convertible senior notes due 2022, or the 2022 Convertible Notes, that we repaid in August 2022 offset by interest income earned on investments.

Critical accounting policies and significant judgments and estimates

Our management’s discussion and analysis of our financial condition and results of operations is based on our financial statements, which we have prepared in accordance with generally accepted accounting principles in the United States. The preparation of these financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported revenues and expenses during the reporting periods. Actual results may differ from these estimates under different assumptions or conditions.

Of our policies, the following are considered critical to an understanding of our consolidated financial statements as they require the application of the most subjective and complex judgment, involving critical accounting estimates and assumptions impacting our consolidated financial statements:

● Revenue recognition related to net product revenue

● Contingent consideration from business combinations

Revenue recognition related to net product revenue

Net product revenues. Our net product revenue primarily consists of sales of Translarna in territories outside of the U.S. and sales of Emflaza in the U.S., both for the treatment of DMD. We recognize revenue when performance obligations with customers have been satisfied. Our performance obligations are to provide products based on customer orders from distributors, hospitals, specialty pharmacies or retail pharmacies. The performance obligations are satisfied at a point in time when our customer obtains control of the product, which is typically upon delivery. We invoice customers after the products have been delivered and invoice payments are generally due within 30 to 90 days of invoice date. We determine the transaction price based on fixed consideration in its contractual agreements. Contract liabilities arise in certain circumstances when consideration is due for goods not yet provided. As we have identified only one distinct performance obligation, the transaction price is allocated entirely to the product sale. In determining the transaction price, a significant financing component does not exist since the timing from when we deliver product to when the customers pay for the product is typically less than one year. Customers in certain countries pay in advance of product delivery. In those instances, payment and delivery typically occur in the same month.

We record product sales net of any variable consideration, which includes discounts, allowances, rebates related to Medicaid and other government pricing programs, and distribution fees. We use the expected value or most likely amount method when estimating variable consideration, unless discount or rebate terms are specified within contracts. The identified variable consideration is recorded as a reduction of revenue at the time revenues from product sales are recognized. These estimates for variable consideration are adjusted to reflect known changes in factors and may impact such estimates in the quarter those changes are known. Revenue recognized does not include amounts of variable consideration that are constrained.

During the years ended December 31, 2023, 2022, and 2021, net product sales in the United States were $255.1 million, $218.3 million, and $187.3 million, respectively, consisting solely of sales of Emflaza, and net product sales outside of the United States were $406.1 million, $316.9 million, and $241.6 million respectively, consisting of sales of Translarna, Tegsedi, Waylivra, and Upstaza. Translarna net product revenues made up $355.8 million, $288.6 million, and $236.0 million of the net product sales outside the United States for the years ended December 31, 2023, 2022, and 2021, respectively. During the years ended December 31, 2023 and 2022, two countries, the United States and Russia, accounted for at least 10% of our net product sales, representing $255.1 million and $86.0 million, and $218.3 million and $59.7

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million, respectively. During the year ended December 31, 2021, only the United States accounted for at least 10% of our net product sales.

In relation to customer contracts, we incur costs to fulfill a contract but do not incur costs to obtain a contract. These costs to fulfill a contract do not meet the criteria for capitalization and are expensed as incurred. We consider any shipping and handling costs that are incurred after the customer has obtained control of the product as a cost to fulfill a promise. Shipping and handling costs associated with finished goods delivered to customers are recorded as a selling expense.

Contingent consideration from business combinations

The consideration for our business acquisitions may include future payments that are contingent upon the occurrence of a particular event or events. The obligations for such contingent consideration payments are recorded at fair value on the acquisition date. The contingent consideration obligations are then evaluated each reporting period. Changes in the fair value of contingent consideration, other than changes due to payments, are recognized as a gain or loss and recorded within the change in the fair value of deferred and contingent consideration on the consolidated statements of operations. The fair value of the development and regulatory milestones are estimated utilizing a probability adjusted, discounted cash flow approach. The discount rates are estimated utilizing Corporate B rated bonds maturing in the years of expected payments based on our estimated development timelines for the acquired product candidate. The fair value of the net sales milestones is determined utilizing a valuation framework that estimates net sales volatility to simulate a range of possible payment scenarios. The average of the payments in these scenarios is then discounted to calculate present fair value.

For a description of our significant accounting policies, see note 2 to our consolidated financial statements.

Year ended December 31, 2023 compared to year ended December 31, 2022

The following table summarizes revenues and selected expense and other income data for the year ended December 31, 2023 and 2022:

Year ended

December 31, Change

Manufacturing revenue 7,687 — $ 7,687

Loss on extinguishment of debt (137,558) — $ (137,558)

Net product revenue. Net product revenue was $661.2 million for the year ended December 31, 2023, an increase of $126.0 million, or 24%, from net product revenue of $535.2 million for the year ended December 31, 2022. Translarna net product revenues were $355.8 million for the year ended December 31, 2023, an increase of $67.2 million, or 23%, compared to $288.6 million for the year ended December 31, 2022. These results were driven by treatment of new patients in existing geographies and continued geographic expansion. Emflaza net product revenues were $255.1 million for the year ended December 31, 2023, an increase of $36.8 million, or 17%, compared to $218.3 million for the year ended

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December 31, 2022. These results were driven by new patient starts and high compliance. The remaining increase of $22.0 million was due to an increase in net product sales of Tegsedi, Waylivra, and Upstaza.

Collaboration revenue. Collaboration revenue was $100.0 million for the year ended December 31, 2023, an increase of $50.0 million, or 100%, from collaboration revenue of $50.1 million for the year ended December 31, 2022. The increase is due to an increase in actual milestones that were achieved in the year ended December 31, 2023 compared to the year ended December 31, 2022, respectively. A sales milestone of $100.0 million was recognized for the achievement of $1.5 billion in worldwide annual net sales from Evrysdi in the year ended December 31, 2023. A sales milestone of $50.0 million was recognized for the achievement of $750.0 million in worldwide annual net sales from Evrysdi in the year ended December 31, 2022.

Royalty revenue. Royalty revenue was $168.9 million for the year ended December 31, 2023, an increase of $55.3 million, or 49%, from $113.5 million for the year ended December 31, 2022. The increase in royalty revenue was due to higher Evrysdi sales in the year ended December 31, 2023 compared to the year ended December 31, 2022. In accordance with the SMA License Agreement, we are entitled to royalties on worldwide annual net sales of the product.

Manufacturing revenue. Manufacturing revenues were $7.7 million for the year ended December 31, 2023, an increase of $7.7 million, or over 100%, from $0.0 million for the year ended December 31, 2022. The increase is due to the manufacturing services related to the production of plasmid DNA and AAV vectors for gene therapy applications for external customers.

Cost of product sales, excluding amortization of acquired intangible asset. Cost of product sales, excluding amortization of acquired intangible asset, was $65.5 million for the year ended December 31, 2023, an increase of $20.8 million, or 47%, from $44.7 million for the year ended December 31, 2022. Cost of product sales excluding amortization of acquired intangible asset, consist primarily of royalty payments associated with Emflaza, Translarna and Upstaza net product sales, excluding contingent payments to Marathon, costs associated with Emflaza, Translarna and Upstaza product sold during the period, inventory reserves, and royalty expense related to royalty revenues and collaboration milestone revenues. The increase in cost of product sales, excluding amortization of acquired intangible asset, is primarily due to the increases in net product revenue, Upstaza inventory reserves, royalty revenues, and collaboration milestone revenue.

Amortization of acquired intangible asset. Amortization of acquired intangible asset was $222.6 million for the year ended December 31, 2023, an increase of $106.1 million, or 91%, from $116.6 million for the year ended December 31, 2022. These amounts are related to the Emflaza rights acquisition, as well as the Waylivra, Tegsedi, and Upstaza intangible assets, which are all being amortized on a straight-line basis over their estimated useful lives. The amortization increase is primarily related to additional Marathon contingent payments for Emflaza.

Research and development expense. Research and development expense was $666.6 million for the year ended December 31, 2023, an increase of $15.1 million, or 2%, compared to $651.5 million for the year ended December 31, 2022. The increase in research and development expenses includes the achievement of a $30.0 million success-based development milestone for the completion of enrollment of a Phase 3 clinical trial for sepiapterin for PKU. The increase also includes restructuring costs from a reduction in workforce in connection with our strategic pipeline prioritization and discontinuation of our preclinical and early research programs in our gene therapy platform in the year ended December 31, 2023. These increases were partially offset by decreases in program spend related to our strategic portfolio prioritization as we continue to focus our resources on our differentiated, high potential research and development programs.

Selling, general and administrative expense. Selling, general and administrative expense was $332.5 million for the year ended December 31, 2023, an increase of $6.5 million, or 2%, from $326.0 million for the year ended December 31, 2022. The increase reflects our continued investment to support our commercial activities including our expanding commercial portfolio. The increase also includes restructuring costs from a reduction in workforce in connection with our strategic pipeline prioritization and discontinuation of our preclinical and early research programs in our gene therapy platform in the year ended December 31, 2023.

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Change in the fair value of contingent consideration. Change in the fair value of contingent consideration was a gain of $127.7 million for the year ended December 31, 2023, a change of $101.8 million, or over 100%, from a gain of $25.9 million for the year ended December 31, 2022. The change is primarily related to our strategic portfolio prioritization and decision to discontinue our preclinical and early research programs in our gene therapy platform, which included programs for Friedreich ataxia and Angelman syndrome, which was announced in May 2023. As a result, we fully impaired the Friedreich ataxia and Angelman syndrome intangible assets and determined that the fair value for all of the contingent consideration payable related to Friedreich ataxia and Angelman syndrome was $0. As a result, we recorded a fair value change of $128.4 million for the year ended December 31, 2023 for the contingent consideration related to Friedreich ataxia and Angelman syndrome

Intangible asset impairment. Intangible asset impairment was $217.8 million for the year ended December 31, 2023, an increase of $184.4 million, or over 100%, from intangible asset impairment of $33.4 million for the year ended December 31, 2022. The change is due to our strategic portfolio prioritization and decision to discontinue our preclinical and early research programs in our gene therapy platform, which included programs for Friedreich ataxia and Angelman syndrome, which was announced in May 2023. As a result, we fully impaired the Friedreich ataxia and Angelman syndrome intangible assets and recorded impairment expense of $217.8 million during the year ended December 31, 2023. During the year ended December 31, 2022, a partial impairment of $33.4 million was recorded due to a decrease in projected cash flows for the Upstaza indefinite lived intangible asset due to refinements in market assumptions.

Interest expense, net. Interest expense, net was $129.2 million for the year ended December 31, 2023, an increase of $38.3 million, or 42%, from interest expense, net of $90.9 million for the year ended December 31, 2022. The increase in interest expense, net was primarily due to interest expense recorded from the liability for the sale of future royalties related to the A&R Royalty Purchase Agreement and the Original Royalty Purchase Agreement.

Other income (expense), net. Other income, net was $10.1 million for the year ended December 31, 2023, a change

of $59.3 million, or over 100%, from other expense, net of $49.2 million for the year ended December 31, 2022. The change in other income (expense), net resulted primarily from unrealized foreign exchange gains of $11.7 million and realized foreign currency exchanges losses of $2.7 million, for the year ended December 31, 2023, as compared to unrealized foreign exchange losses of $14.4 million and a non cash foreign currency remeasurement loss of $16.9 million from the remeasurement of our intercompany loan for the year ended December 31, 2022. In addition, we had unrealized and realized losses on our equity investments and convertible debt security in ClearPoint Neuro, Inc. (formerly MRI Interventions, Inc.), or ClearPoint, of $2.7 million and $2.3 million, respectively, for the year ended December 31, 2023, as compared to unrealized losses on our equity investments and convertible debt security in ClearPoint, of $3.5 million and $5.8 million, respectively, for the year ended December 31, 2022.

Loss on extinguishment of debt. Loss on extinguishment of debt was $137.6 million for the year ended December 31, 2023, an increase of $137.6 million, or 100%, from loss on extinguishment of debt of $0.0 million for the year ended December 31, 2022. The increase was primarily due to the early termination of our Blackstone Credit Agreement. We recorded a loss on the extinguishment of debt of $92.7 million for the period ended December 31, 2023. The loss on extinguishment of debt consisted of $82.0 million in prepayment premiums, exit fees, and creditor expenses and debt issuance costs of $10.7 million. In addition, we recorded $44.9 million on the loss of extinguishment of debt relating to the A&R Royalty Purchase Agreement.

Income tax benefit. Income tax benefit was $69.5 million for the year ended December 31, 2023, an increase of $41.0 million, or over 100%, from income tax benefit of $28.5 million for the year ended December 31, 2022. The increase in income tax benefit is attributable to the receipt of an outstanding state tax refund received during the year ended December 31, 2023, and the subsequent release of the associated ASC 740 income tax reserve, as well as the reversal of the deferred tax liability recognized in conjunction with the discontinuation of our preclinical and early research programs in our gene therapy platform, which included programs for Friedreich ataxia and Angelman syndrome, during the year ended December 31, 2023.

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Year ended December 31, 2022 compared to year ended December 31, 2021

The following table summarizes revenues and selected expense and other income data for the years ended December 31, 2022 and 2021:

Year ended

December 31, Change

Intangible asset impairment 33,384 — $ 33,384

Net product revenue. Net product revenue was $535.2 million for the year ended December 31, 2022, an increase of $106.3 million, or 25%, from net product revenue of $428.9 million for the year ended December 31, 2021. Translarna net product revenues were $288.6 million for the year ended December 31, 2022, an increase of $52.6 million, or 22%, compared to $236.0 million for the year ended December 31, 2021. These results were driven by treatment of new patients in existing geographies and continued geographic expansion. Emflaza net product revenues were $218.3 million for the year ended December 31, 2022, an increase of $31.0 million, or 17%, compared to $187.3 million for the year ended December 31, 2021. These results were driven by new patient prescriptions, continued high compliance, and appropriate weight-based dosing. The remaining increase of $22.7 million was due to an increase in net product sales of Tegsedi, Waylivra, and Upstaza.

Collaboration revenue. Collaboration revenue was $50.1 million for the year ended December 31, 2022, a decrease of $5.0 million, or 9%, from collaboration revenue of $55.0 million for the year ended December 31, 2021. The decrease is due to a decrease in actual milestones that were achieved in the year ended December 31, 2022 compared to the year ended December 31, 2021, respectively. A sales milestone of $50.0 million was recognized for the achievement of $750.0 million in worldwide annual net sales from Evrysdi in the year ended December 31, 2022. In March 2021, the first commercial sale of Evrysdi in the EU was made. This event triggered a $20.0 million milestone payment to us from Roche. Additionally, in June 2021, the Japanese Ministry of Health, Labor and Welfare approved Evrysdi for the treatment of SMA in Japan. In August 2021, the first commercial sale of Evrysdi in Japan triggered a $10.0 million milestone payment to us from Roche. In December 2021, we recorded our first sales milestone of $25.0 million for the achievement of $500.0 million in worldwide annual net sales from Evrysdi.

Royalty revenue. Royalty revenue was $113.5 million for the year ended December 31, 2022, an increase of $58.9 million, or over 100%, from $54.6 million for the year ended December 31, 2021. The increase in royalty revenue was due to higher Evrysdi sales in the year ended December 31, 2022 as compared to the year ended December 31, 2021. In accordance with the SMA License Agreement, we are entitled to royalties on worldwide annual net sales of the product.

Cost of product sales, excluding amortization of acquired intangible asset. Cost of product sales, excluding amortization of acquired intangible asset, was $44.7 million for the year end December 31, 2022, an increase of $12.4 million, or 38%, from $32.3 million for the year ended December 31, 2021. Cost of product sales, excluding amortization of acquired intangible asset, consist primarily of royalty payments associated with Emflaza, Translarna and Upstaza net product sales, excluding contingent payments to Marathon, costs associated with Emflaza, Translarna and Upstaza product

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sold during the period, and royalty expense related to royalty revenues and collaboration milestone revenues. The increase in cost of product sales, excluding amortization of acquired intangible asset, is primarily due to the increases in net product revenue, royalty revenues, and collaboration milestone revenue.

Amortization of acquired intangible asset. Amortization of acquired intangible asset was $116.6 million for the year ended December 31, 2022, an increase of $61.8 million, or over 100%, from $54.8 million for the year ended December 31, 2021. These amounts are related to the Emflaza rights acquisition, as well as the Waylivra, Tegsedi, and Upstaza intangible assets, which are all being amortized on a straight-line basis over their estimated useful lives. With the approval of Upstaza by the EC in July 2022, $89.6 million was reclassified from indefinite lived intangible assets to definite lived intangible assets, which is being amortized over its expected useful life. The amortization increase is primarily related to the additional Marathon contingent payments, which includes a $50.0 million contingent payment made in the year ended December 31, 2022.

Research and development expense. Research and development expense was $651.5 million for the year ended December 31, 2022, an increase of $110.8 million, or 20%, compared to $540.7 million for the year ended December 31, 2021. The increase in research and development expenses is primarily related to increased investment in research programs and advancement of the clinical pipeline.

Selling, general and administrative expense. Selling, general and administrative expense was $326.0 million for the year ended December 31, 2022, an increase of $40.2 million, or 14%, from $285.8 million for the year ended December 31, 2021. The increase reflects our continued investment to support our commercial activities including our expanding commercial portfolio.

Change in the fair value of contingent consideration. Change in the fair value of contingent consideration was a gain of $25.9 million for the year ended December 31, 2022, a change of $25.4 million, or over 100%, from a gain of $0.5 million for the year ended December 31, 2021. The change is related to the fair valuation of the potential future consideration to be paid to former equityholders of Agilis as a result of our merger with Agilis which closed in August 2018. Changes in the fair value were due to the re-calculation of discounted cash flows for the passage of time and changes to certain other estimated assumptions.

Intangible asset impairment. Intangible asset impairment was $33.4 million for the year ended December 31, 2022, an increase of $33.4 million, 100%, from intangible asset impairment of $0.0 million for the year ended December 31, 2021. The increase was due to a decrease in projected cash flows for the Upstaza indefinite lived intangible asset due to refinements in current market assumptions and the timing of patient treatments, resulting in a partial impairment.

Interest expense, net. Interest expense, net was $90.9 million for the year ended December 31, 2022, an increase of $4.8 million, 6%, from interest expense, net of $86.0 million for the year ended December 31, 2021. The increase in interest expense, net was primarily due to interest expense recorded from the senior secured term loan, partially offset by lower interest expense due to the repayment of the 2022 Convertible Notes.

Other expense, net. Other expense, net was $49.2 million for the year ended December 31, 2022, a decrease of $8.7 million, 15%, from other expense, net of $57.9 million for the year ended December 31, 2021. The decrease in other expense, net resulted primarily from an unrealized foreign exchange loss of $14.4 million and a non cash foreign currency remeasurement loss of $16.9 million from the remeasurement of our intercompany loan for the year end December 31, 2022, as compared to an unrealized foreign exchange loss of $41.0 million from the remeasurement of our intercompany loan for the year ended December 31, 2021. In addition, we had unrealized losses on our equity investments and convertible debt security in ClearPoint, of $3.5 million and $5.8 million, respectively, for the year ended December 31, 2022, as compared to unrealized losses on our equity investments and convertible debt security in ClearPoint of $6.1 million and $8.3 million, respectively, for the year ended December 31, 2021

Income tax benefit (expense). Income tax benefit was $28.5 million for the year ended December 31, 2022, a change of $34.0 million, or over 100%, from income tax expense of $5.6 million for the year ended December 31, 2021. The change in income tax benefit (expense) is primarily attributable to the partial amortization of an intangible which had

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previously been classified as an indefinite lived intangible, and the subsequent release of a portion of the valuation allowance associated with this asset.

Liquidity and capital resources

Sources of liquidity

Since inception, we have incurred significant operating losses.

As a growing commercial-stage biopharmaceutical company, we are engaging in significant commercialization efforts for our products while also devoting a substantial portion of our efforts on research and development related to our products, product candidates and other programs. To date, our product revenue has primarily consisted of sales of Translarna for the treatment of nmDMD in territories outside of the United States and from Emflaza for the treatment of DMD in the United States. Our ongoing ability to generate revenue from sales of Translarna for the treatment of nmDMD is dependent upon our ability to maintain our marketing authorizations in Brazil, Russia and in the EEA and secure market access through commercial programs following the conclusion of pricing and reimbursement terms at sustainable levels in the member states of the EEA or through EAP programs or similar styled programs in the EEA and other territories. On January 25, 2024, the CHMP issued a negative opinion for the renewal of the conditional marketing authorization following a re-examination procedure. In accordance with EMA regulations, the EC has 67 days to adopt the opinion from the date of its issuance. If the EC adopts the negative opinion, Translarna would no longer have marketing authorization in the EEA. Emflaza is approved in the United States for the treatment of DMD in patients two years and older. Our ability to generate product revenue from Emflaza will largely depend on the coverage and reimbursement levels set by governmental authorities, private health insurers and other third-party payors. Additionally, Emflaza’s seven-year period of orphan drug exclusivity related to the treatment of DMD in patients five years and older expired in February 2024. We have previously relied on this exclusivity period to commercialize Emflaza in the United States. We expect the expiration of this orphan drug exclusivity to have a significant negative impact on Emflaza net product revenue. Emflaza’s orphan drug exclusivity related to the treatment of DMD in patients two years of age to less than five expires in June 2026.

We have financed our operations to date primarily through private offerings of convertible senior notes, public and “at the market offerings” of common stock, proceeds from royalty purchase agreements, net proceeds from our borrowings under our credit agreement with Blackstone, private placements of our convertible preferred stock and common stock, collaborations, bank and institutional lender debt, other convertible debt, grant funding and clinical trial support from governmental and philanthropic organizations and patient advocacy groups in the disease area addressed by our product candidates. We expect to continue to incur significant expenses and operating losses for at least the next fiscal year. The net losses we incur may fluctuate significantly from quarter to quarter.

In August 2019, we entered into the Sales Agreement, pursuant to which, we may offer and sell shares of our common stock, having an aggregate offering price of up to $125.0 million from time to time through the Sales Agents by any method that is deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act. See “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations—Overview—Funding” for additional information regarding the transactions described in this paragraph.

In September 2019, we issued $287.5 million aggregate principal amount of 2026 Convertible Notes, which included an option to purchase up to an additional $37.5 million in aggregate principal amount of the 2026 Convertible Notes, which was exercised in full by the initial purchasers. The 2026 Convertible Notes bear cash interest at a rate of 1.50% per year, payable semi-annually on March 15 and September 15 of each year, beginning on March 15, 2020. The 2026 Convertible Notes will mature on September 15, 2026, unless earlier repurchased or converted. We received net proceeds of $279.3 million after deducting the initial purchasers’ discounts and commissions and the offering expenses payable by us.

Holders may convert their 2026 Convertible Notes at their option at any time prior to the close of business on the business day immediately preceding March 15, 2026 only under the following circumstances: (1) during any calendar quarter commencing on or after December 31, 2019 (and only during such calendar quarter), if the last reported sale price of our common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive

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trading days ending on the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day; (2) during the five business day period after any five consecutive trading day period, or the measurement period, in which the trading price (as defined in the 2026 Convertible Notes Indenture) per $1,000 principal amount of 2026 Convertible Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of our common stock and the conversion rate on each such trading day; (3) during any period after we have issued notice of redemption until the close of business on the scheduled trading day immediately preceding the relevant redemption date; or (4) upon the occurrence of specified corporate events. On or after March 15, 2026, until the close of business on the business day immediately preceding the maturity date, holders may convert their 2026 Convertible Notes at any time, regardless of the foregoing circumstances. Upon conversion, we will pay or deliver, as the case may be, cash, shares of our common stock or any combination thereof at our election.

The conversion rate for the 2026 Convertible Notes was initially, and remains, 19.0404 shares of our common stock per $1,000 principal amount of the 2026 Convertible Notes, which is equivalent to an initial conversion price of approximately $52.52 per share of our common stock. The conversion rate may be subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest.

We were not permitted to redeem the 2026 Convertible Notes prior to September 20, 2023. We may redeem for cash all or any portion of the 2026 Convertible Notes, at our option, if the last reported sale price of our common stock has been at least 130% of the conversion price then in effect on the last trading day of, and for at least 19 other trading days (whether or not consecutive) during, any 30 consecutive trading day period ending on, and including, the trading day immediately preceding the date on which we provide notice of redemption, at a redemption price equal to 100% of the principal amount of the 2026 Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. No sinking fund is provided for the 2026 Convertible Notes, which means that we are not required to redeem or retire the 2026 Convertible Notes periodically.

If we undergo a “fundamental change” (as defined in the 2026 Convertible Notes Indenture), subject to certain conditions, holders of the 2026 Convertible Notes may require us to repurchase for cash all or part of their 2026 Convertible Notes at a repurchase price equal to 100% of the principal amount of the 2026 Convertible Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date.

The 2026 Convertible Notes represent senior unsecured obligations and will rank senior in right of payment to our future indebtedness that is expressly subordinated in right of payment to the notes, equal in right of payment to our existing and future unsecured indebtedness that is not so subordinated, effectively junior in right of payment to any of our secured indebtedness to the extent of the value of the assets securing such indebtedness, and structurally subordinated to all existing and future indebtedness and other liabilities (including trade payables) incurred by our subsidiaries. The 2026 Convertible Notes Indenture contains customary events of default with respect to the 2026 Convertible Notes, including that upon certain events of default (including our failure to make any payment of principal or interest on the 2026 Convertible Notes when due and payable) occurring and continuing, the 2026 Convertible Notes Trustee by notice to us, or the holders of at least 25% in principal amount of the outstanding 2026 Convertible Notes by notice to us and the Convertible Notes Trustee, may, and the 2026 Convertible Notes Trustee at the request of such holders (subject to the provisions of the 2026 Convertible Notes Indenture) will, declare 100% of the principal of and accrued and unpaid interest, if any, on all the 2026 Convertible Notes to be due and payable. In case of certain events of bankruptcy, insolvency or reorganization, involving us or a significant subsidiary, 100% of the principal of and accrued and unpaid interest on the 2026 Convertible Notes will automatically become due and payable. Upon such a declaration of acceleration, such principal and accrued and unpaid interest, if any, will be due and payable immediately.

In July 2020, we entered into the Original Royalty Purchase Agreement. Pursuant to the Original Royalty Purchase Agreement, we sold to Royalty Pharma the Original Assigned Royalty Rights in consideration for $650.0 million. See “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations—Overview—Funding” for additional information regarding this transaction.

In October 2022, we entered into the Blackstone Credit Agreement for fundings of up to $950.0 million consisting of a committed loan facility consisting of a senior secured term loan facility funded on the Closing Date, in the aggregate

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principal amount of $300.0 million, and a delayed draw term loan facility of up to $150.0 million to be funded at our request within 18 months of the Closing Date subject to specified conditions, and further contemplating the potential for up to $500.0 million of additional financing, to the extent that we request such additional financing and subject to the Lenders’ agreement to provide such additional financing and to mutual agreement on terms. In October 2023, we terminated the Blackstone Credit Agreement. We recorded a loss on the extinguishment of debt of $92.7 million which is included on the statement of operations for the period ended December 31, 2023. The loss on extinguishment of debt consisted of $82.0 million in prepayment premiums, exit fees, and creditor expenses and debt issuance costs of $10.7 million. All liens and security interests securing the loans made pursuant to the Blackstone Credit Agreement were released upon termination.

In October 2023, we entered into the A&R Royalty Purchase Agreement. At closing, Royalty Pharma paid us $1.0 billion in cash consideration for 38.0447% of our Retained Royalty Rights (which is in addition to the Original Assigned Royalty Rights, for a total of 80.9777% of the total Royalty) until such time as Royalty Pharma has received payments in respect of the Original Assigned Royalty Rights equal to $1.3 billion in the aggregate, and thereafter 66.6667% of the total Royalty. In addition, we may sell to Royalty Pharma the remainder of our Retained Royalty Rights in exchange for an aggregate of $500.0 million in additional cash consideration after the closing of the A&R Royalty Purchase Agreement, less royalties received in respect of the Retained Royalty Rights put to Royalty Pharma, which will be payable by Royalty Pharma pursuant to five put options held by us that are exercisable at our option between January 1, 2024 and December 31, 2025. If we exercise two or fewer of the put options, Royalty Pharma may exercise a call option during the period from and after January 1, 2026 until and including March 31, 2026 for up to 50% of the remainder of our Retained Royalty Rights less amounts exercised by us via our put options at a purchase price that is proportional to the purchase price of our unexercised put options. Royalty Pharma’s exercise of the call option would result in Royalty Pharma owning 90.4888% of the total Royalty until such time as Royalty Pharma has received payments in respect of the Original Assigned Royalty Rights equal to $1.3 billion in the aggregate, and thereafter 83.3333% of the total Royalty.

The A&R Royalty Purchase Agreement includes specified negative and affirmative covenants with respect to our rights under the SMA License Agreement as well as other customary representations and warranties, covenants and other provisions. The A&R Royalty Purchase Agreement will terminate 60 days following the date on which Roche is no longer obligated to make any payments of the Royalty pursuant to the SMA License Agreement.

Cash flows

As of December 31, 2023, we had cash and cash equivalents and marketable securities of $876.7 million.

The following table provides information regarding our cash flows and our capital expenditures for the periods indicated.

Years ended

December 31,

Cash (used in) provided by:

Net cash used in operating activities was $158.4 million, $356.7 million, and $251.3 million for the years ended December 31, 2023, 2022, and 2021, respectively. The net cash used in operating activities primarily relates to supporting clinical development and commercial activities for the years ended December 31, 2023, 2022, and 2021.

Net cash used in investing activities was $176.7 million for the year ended December 31, 2023. Net cash provided by investing activities was $290.2 million and 219.2 million for the years ended December 31, 2022, and 2021, respectively. The cash used in investing activities for the year ended December 31, 2023 is primarily attributable to the purchases of marketable securities – available for sale, purchases of marketable securities – equity investments, purchases of fixed assets, and the acquisition of product rights, offset by the sale and redemption of marketable securities – available for sale,

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sale and redemption of marketable securities – equity investments, and the sale and redemption of ClearPoint Equity Investments. The cash provided by investing activities for the years ended December 31, 2022 and December 31, 2021 were primarily related to net sales and redemptions of marketable securities – available for sale and net sales and redemptions of marketable securities – equity investments, partially offset by purchases of marketable securities – available for sale, purchases of marketable securities – equity investments, purchases of fixed assets, and the acquisition of product rights.

Net cash provided by financing activities was $646.4 million, $168.0 million, and $20.9 million for the years ended December 31, 2023, 2022 and 2021, respectively. The cash provided by financing activities for the year ended December 31, 2023 is primarily attributable to the proceeds received from the A&R Royalty Purchase Agreement, exercise of options, issuance of stock under our Employee Stock Purchase Plan, or ESPP, offset by the repayment of the senior secured term loan, debt issuance costs, debt extinguishment costs related to senior secured term loan, and payments on our finance lease principal. The cash provided by financing activities for the year ended December 31, 2022 is primarily attributable to the proceeds from the issuance of the senior secured term loan under the Blackstone Credit Agreement, the stock purchase agreement entered into in connection with the execution of the Blackstone Credit Agreement, the exercise of options, and issuance of stock under our ESPP, offset by the repayment of the 2022 Convertible Notes, payments on contingent consideration obligation, and payments on our finance lease principal. The cash provided by financing activities for the year ended December 31, 2021 is primarily attributable to the exercise of options, and issuance of stock under our ESPP offset by payments on our finance lease principal.

Funding requirements

We anticipate that we will continue to incur significant expenses in connection with our commercialization efforts in the United States, the EEA, Latin America and other territories, including expenses related to our commercial infrastructure and corresponding sales and marketing, legal and regulatory, and distribution and manufacturing undertakings as well as administrative and employee-based expenses. In addition to the foregoing, we expect to continue to incur significant costs in connection with ongoing, planned and potential future clinical trials and studies for sepiapterin and our splicing and ferroptosis and inflammation programs as well as studies in our products for maintaining authorizations, label extensions and additional indications. We continue to seek marketing authorization for Translarna for the treatment of nmDMD in territories that we do not currently have marketing authorization in and we are exploring other potential mechanisms in which we may provide Translarna to nmDMD patients in the EEA if the EC ratifies the CHMP’s negative opinion for Translarna following a re-examination procedure. We anticipate submitting a BLA to the FDA for Upstaza for the treatment of AADC deficiency in the United States in March 2024. We also expect to submit an MAA to the EMA for sepiapterin for the treatment of PKU in March 2024 and we expect to submit an NDA to the FDA for sepiapterin for the treatment of PKU no later than the third quarter of 2024. These efforts may significantly impact the timing and extent of our commercialization and manufacturing expenses.

In addition, our expenses will increase if and as we:

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● seek to discover and develop additional product candidates;

● maintain, expand and protect our intellectual property portfolio; and

We believe that our cash flows from product sales, together with existing cash and cash equivalents, and marketable securities, will be sufficient to fund our operating expenses and capital expenditure requirements for at least the next twelve months. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect.

Our future capital requirements will depend on many factors, including:

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● the timing and scope of any potential future growth in our employee base;

With respect to our outstanding 2026 Convertible Notes, cash interest payments are payable on a semi-annual basis in arrears, which will require total funding of $4.3 million annually.

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We expect to make additional payments to the former Censa securityholders of $65.0 million in the aggregate in cash upon the potential achievement in 2024 of certain regulatory milestones relating to sepiapterin pursuant to the Censa Merger Agreement. We also expect to pay the former equityholders of Agilis $20.0 million in development milestone payments upon the acceptance for filing by the FDA of a BLA for Upstaza for the treatment of AADC deficiency and $4.5 million in regulatory milestone payments upon the approval of the BLA from the FDA. We anticipate submitting a BLA to the FDA for Upstaza for the treatment of AADC deficiency in the United States in March 2024. Furthermore, since we are a public company, we have incurred and expect to continue to incur additional costs associated with operating as such including significant legal, accounting, investor relations and other expenses.

We also have certain significant contractual obligations and commercial commitments that require funding. We lease office space for our principal office in South Plainfield, New Jersey and we occupy under leases that expire in 2024, with two consecutive five-year renewal options to renew the leases after 2024. Additionally, we entered into a lease agreement for approximately 103,000 square feet of laboratory and office space in Bridgewater, New Jersey. The rental term for such facility commenced on May 1, 2020 with an initial term of seven years and two consecutive five year renewal periods at our option. We have significant lease obligations that stem from our lease of office, manufacturing, and laboratory space in Hopewell, New Jersey. The rental term for such facility commenced on July 1, 2020, with an initial term of fifteen years and two consecutive 10-year renewal periods at our option. We also lease two entire buildings comprised of approximately 360,000 square feet of shell condition, modifiable space at a facility located in Warren, New Jersey. The rental term for such facility commenced on June 1, 2022, with an initial term of seventeen years followed by three consecutive five-year renewal periods at our option. In addition, we lease office space, vehicles and equipment in various other locations in the U.S. and other countries for our employees and operations. We have a total of $252.6 million in obligations that stem from our operating leases.

We have a total of $27.0 million in obligations that stem from a commercial manufacturing services agreement entered into with MassBio on June 19, 2020, for a term of 12.5 years. Pursuant to the terms of the agreement, MassBio agreed to provide us with four dedicated rooms for our Upstaza program.

Under an Exclusive License and Supply Agreement, or the Faes Agreement, with Faes Farma, S.A., or Faes, we are required to pay royalties as a percentage of or as a fixed payment with respect to net product sales by us allocable to the Emflaza oral suspension product. We are required to pay Faes an annual minimum royalty during the first seven calendar years from the FDA approval date of the Emflaza oral suspension product. The minimum royalty based on the euro to U.S. dollar exchange rate as of December 31, 2023 is $1.7 million, which represents the last annual minimum royalty payment due. Thereafter, a fixed percentage royalty is due during the remainder of the Faes Agreement term.

Under various agreements, including the sponsored research agreement with the SMA Foundation discussed below, we will be required to pay royalties and milestone payments upon the successful development and commercialization of products.

We have entered into a sponsored research agreement with the SMA Foundation in connection with our spinal muscular atrophy program. We may become obligated to pay the SMA Foundation single-digit royalties on worldwide net product sales of any collaboration product that we successfully develop and subsequently commercialize or, with respect to collaboration products we outlicense, including Evrysdi, a specified percentage of certain payments we receive from our licensee. We are not obligated to make such payments unless and until annual sales of a collaboration product exceed a designated threshold. Since inception, the SMA Foundation has earned $52.5 million, $35.3 million which was paid and $17.2 million which was accrued as of December 31, 2023. We have reached our obligation to make such payments to the SMA Foundation of an aggregate of $52.5 million as of December 31, 2023. Refer to “Ongoing Acquisition- Related Obligations” in Item 1. Business.

Additionally, we have employment agreements with certain employees which require the funding of a specific level of payments, if certain events, such as a change in control or termination without cause, occur.

We have never been profitable and we will need to generate significant revenues to achieve and sustain profitability, and we may never do so. We may need to obtain substantial additional funding in connection with our continuing operations. Until such time, if ever, as we can generate substantial product revenues, we expect to finance our cash needs

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primarily through a combination of equity offerings, debt financings, collaborations, strategic alliances, grants and clinical trial support from governmental and philanthropic organizations and patient advocacy groups in the disease areas addressed by our product and product candidates and marketing, distribution or licensing arrangements. Adequate additional financing may not be available to us on acceptable terms, or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, our stockholders ownership interest will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or to grant licenses on terms that may not be favorable to us.

If we are unable to raise additional funds through equity, debt or other financings when needed or on attractive terms, we may be required to delay, limit, reduce or terminate our product development or commercialization efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

We are exposed to market risk related to changes in interest rates. Our primary exposure to market risk is interest rate sensitivity, which is affected by changes in the general level of U.S. interest rates, particularly because our investments are in short-term securities. Our available for sale securities are subject to interest rate risk and will fall in value if market interest rates increase. At any time, sharp changes in interest rates can affect the fair value of the investment portfolio and its interest earnings. There were no investments classified as long-term at December 31, 2023. At December 31, 2023, we held $876.7 million in cash and cash equivalents and short-term investments. After a review of our marketable investment securities, we believe that in the event of a hypothetical ten percent increase in interest rates, the resulting decrease in fair value of our marketable investment securities would be insignificant to the consolidated financial statements.

Currently, we do not hedge these interest rate exposures. We maintain an investment portfolio in accordance with our investment policy. The primary objectives of our investment policy are to preserve principal, maintain proper liquidity and to meet operating needs. Although our investments are subject to credit risk, our investment policy specifies credit quality standards for our investments and limits the amount of credit exposure from any single issue, issuer or type of investment. Our investments are also subject to interest rate risk and will decrease in value if market interest rates increase. However, due to the conservative nature of our investments and relatively short duration, interest rate risk is mitigated. We do not own derivative financial instruments. Accordingly, we do not believe that there is any material market risk exposure with respect to derivative or other financial instruments.

As a result of our ex-U.S. operations, we face exposure to movements in foreign currency exchange rates, including the British Pound, Euro, Brazilian Real, and Swiss Franc against the U.S. dollar. The current exposures arise primarily from cash, accounts receivable, intercompany receivables and payables, intercompany loans and product sales denominated in foreign currencies. Both positive and negative impacts to our international product sales from movements in foreign currency exchange rates may be partially mitigated by the natural, opposite impact that foreign currency exchange rates have on our international operating expenses. For the year ended December 31, 2023, we recognized realized foreign currency transaction losses, net, of $2.7 million, which is recorded within other income, net on the Statement of Operations. A hypothetical ten percent increase or decrease in the exchange rate between the U.S. dollar and the British Pound, Euro, Brazilian Real, or Swiss Franc from the December 31, 2023 rate would not have a significant impact on our cash flows. We are not currently engaged in any foreign currency hedging activities. We will evaluate the use of derivative financial instruments to hedge our exposure as the needs and risks should arise.

In September 2019, we issued $287.5 million of 1.50% convertible senior notes due September 15, 2026, or the 2026 Convertible Notes. We do not have economic interest rate exposure on the 2026 Convertible Notes as they have a fixed annual interest rate of 1.50%. However, the fair value of the 2026 Convertible Notes is exposed to interest rate risk. We do not carry the 2026 Convertible Notes at fair value on our balance sheet but present the fair value of the principal amount for disclosure purposes. Generally, the fair value of the 2026 Convertible Notes will increase as interest rates fall and decrease as interest rates rise. The 2026 Convertible Notes are also affected by the price and volatility of our common

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stock and will generally increase or decrease as the market price of our common stock changes. The estimated fair value of the 2026 Convertible Notes was approximately $265.3 million as of December 31, 2023.

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Item 8. Financial Statements and Supplementary Data

Index to consolidated financial statements

Report of Independent Registered Public Accounting Firm (PCAOB ID 42) 139

Notes to Consolidated Financial Statements 148

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Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of PTC Therapeutics, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of PTC Therapeutics, Inc. (the Company) as of December 31, 2023 and 2022, the related consolidated statements of operations, comprehensive loss, stockholders' (deficit)/equity and cash flows for each of the three years in the period ended December 31, 2023, 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, 2023 and 2022, and the consolidated results of its operations and its cash flows for each of the three years in the period ended December 31, 2023, 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, 2023, 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 29, 2024 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 included 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 Matters

The critical audit matters communicated below are matters arising from the current period audit of the financial statements that were communicated or required to be communicated to the audit committee and that: (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of critical audit matters 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 matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Variable consideration in contracts with customers

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Valuation of acquisition-related contingent consideration liability

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/s/ Ernst & Young LLP

We have served as the Company’s auditor since 2010.

Iselin, New Jersey

February 29, 2024

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PTC Therapeutics, Inc.

Consolidated Balance Sheets

In thousands, except shares

December 31,

Assets

Current assets:

Prepaid expenses and other current assets 150,491 105,658

Liabilities and stockholders’ deficit

Current liabilities:

Operating lease liabilities- current 13,002 9,370

Finance lease liabilities- current 3,000 3,000

Liability for sale of future royalties- current 194,314 72,149

Operating lease liabilities- noncurrent 97,627 100,860

Finance lease liabilities- noncurrent 17,184 18,675

Liability for sale of future royalties- noncurrent 1,619,783 685,737

Other long-term liabilities 141 2,641

Stockholders’ deficit:

Accumulated other comprehensive (loss) income (1,285) 4,796

Total liabilities and stockholders’ deficit $ 1,895,698 $ 1,705,619

See accompanying consolidated notes.

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PTC Therapeutics, Inc.

Consolidated Statements of Operations

In thousands, except shares and per share data

Year ended December 31,

Revenues:

Manufacturing revenue 7,687 — —

Operating expenses:

Intangible asset impairment 217,800 33,384 —

Loss on extinguishment of debt (137,558) — —

Weighted-average shares outstanding:

See accompanying consolidated notes.

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PTC Therapeutics, Inc.

Consolidated Statements of Comprehensive Loss

In thousands

Year ended December 31,

Other comprehensive income (loss):

See accompanying consolidated notes.

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PTC Therapeutics, Inc.

Consolidated Statements of Stockholders’ Equity/ (Deficit)

In thousands, except shares

Accumulated

Additional other Total

Common stock paid-in comprehensive Accumulated stockholders’

Shares Amount capital (loss) income deficit equity (deficit)

Restricted stock vesting and issuance, net 307,658 — — — — —

Share-based compensation expense — — 103,513 — — 103,513

Receivable from investor — — 483 — — 483

Other — — — — 25 25

Comprehensive income — — — 36,675 — 36,675

Restricted stock vesting and issuance, net 490,008 — — — — —

Share-based compensation expense — — 110,333 — — 110,333

Comprehensive income — — — 29,078 — 29,078

Restricted stock vesting and issuance, net 915,203 1 — — — 1

Share-based compensation expense — — 101,636 — — 101,636

Receivable from investor — — 15 — — 15

Comprehensive loss — — — (6,081) — (6,081)

See accompanying consolidated notes.

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PTC Therapeutics, Inc.

Consolidated Statements of Cash Flows

In thousands

Year ended December 31,

Cash flows from operating activities

Intangible asset impairment 217,800 33,384 —

Change in valuation of contingent consideration (127,700) (25,900) (500)

Unrealized loss on ClearPoint Equity Investments 1,515 3,560 6,078

Realized loss for the sale of Clearpoint Equity Investment 782 — —

Non-cash stock consideration, milestone payment 29,570 — —

Disposal of asset 806 80 —

Amortization of debt issuance costs 1,873 1,901 1,848

Loss on extinguishment of debt 55,625 — —

Prepaid expenses and other current assets (44,992) (51,621) (15,310)

Payments on contingent consideration — (9,600) —

Cash flows from investing activities

Sale and redemption of ClearPoint Equity Investments 2,594 — —

Purchase of equity investment in Clearpoint — — (100)

Cash flows from financing activities

Repayment of senior secured term loan (300,000) — —

Proceeds from issuance of senior secured term loan — 300,000 —

Repayment of Convertible Notes — (150,000) —

Proceeds from employee stock purchase plan 5,954 6,450 5,792

Payment of finance lease principal (1,379) (1,276) (2,224)

Proceeds from stock purchase agreement — 50,000 —

Effect of exchange rate changes on cash 3,114 (2,772) (7,821)

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Supplemental disclosure of cash information

Supplemental disclosure of non-cash investing and financing activity

Acquisition of product rights and licenses $ 54,618 $ 33,239 $ 22,294

Milestone payable $ 2,500 $ — $ —

Debt issuance costs related to senior secured term loan $ — $ 159 $ —

Capital expenditures unpaid at the end of the period $ — $ 308 $ —

See accompanying consolidated notes.

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PTC Therapeutics, Inc.

Notes to consolidated financial statements

December 31, 2023

(In thousands except share and per share amount)

1. The Company

PTC Therapeutics, Inc. (the “Company” or “PTC”) is a global biopharmaceutical company focused on the discovery, development and commercialization of clinically differentiated medicines that provide benefits to patients with rare disorders. PTC’s ability to innovate to identify new therapies and to globally commercialize products is the foundation that drives investment in a robust and diversified pipeline of transformative medicines. PTC’s mission is to provide access to best-in-class treatments for patients who have little to no treatment options. PTC’s strategy is to leverage its strong scientific and clinical expertise and global commercial infrastructure to bring therapies to patients. PTC believes that this allows it to maximize value for all of its stakeholders.

The Company has two products, TranslarnaTM (ataluren) and Emflaza® (deflazacort), for the treatment of Duchenne muscular dystrophy (“DMD”), a rare, life threatening disorder. Translarna has marketing authorization in the European Economic Area (the “EEA”) for the treatment of nonsense mutation Duchenne muscular dystrophy (“nmDMD”) in ambulatory patients aged 2 years and older. In July 2020, the European Commission (“EC”) approved the removal of the statement “efficacy has not been demonstrated in non-ambulatory patients” from the indication statement for Translarna. Translarna also has marketing authorization in Russia for the treatment of nmDMD in patients aged two years and older, and in Brazil for the treatment of nmDMD in ambulatory patients two years and older and for continued treatment of patients that become non-ambulatory, as well as in various other countries. Emflaza is approved in the United States for the treatment of DMD in patients two years and older.

The Company’s marketing authorization for Translarna in the EEA is subject to annual review and renewal by the EC following reassessment by the European Medicines Agency (“EMA”) of the benefit-risk balance of the authorization, which the Company refers to as the annual EMA reassessment. In September 2022, the Company submitted a Type II variation to the EMA to support conversion of the conditional marketing authorization for Translarna to a standard marketing authorization, which included a report on the placebo-controlled trial of Study 041 and data from the open-label extension. In February 2023, the Company also submitted an annual marketing authorization renewal request to the EMA. In September 2023, the Committee for Medicinal Products for Human Use (“CHMP’), gave a negative opinion on the conversion of the conditional marketing authorization to full marketing authorization of Translarna for the treatment of nmDMD and a negative opinion on the renewal of the existing conditional marketing authorization of Translarna for the treatment of nmDMD. On January 25, 2024, the CHMP issued a negative opinion for the renewal of the conditional marketing authorization following a re-examination procedure. In accordance with EMA regulations, the EC has 67 days to adopt the opinion. If the EC adopts the negative opinion, Translarna would no longer have marketing authorization in the member states of the EEA.

Translarna is an investigational new drug in the United States. Following the Company’s announcement of top-line results from the placebo-controlled trial of Study 041 in June 2022, the Company submitted a meeting request to the U.S. Food and Drug Administration (“FDA”) to gain clarity on the regulatory pathway for a potential re-submission of a New Drug Application (“NDA”) for Translarna. The FDA provided initial written feedback that Study 041 does not provide substantial evidence of effectiveness to support NDA re-submission. The Company held a Type C meeting with the FDA in the fourth quarter of 2023 to discuss the totality of Translarna data. Based on this discussion, the FDA suggested that the Company request a pre-submission Type C meeting to discuss the specific contents of an NDA resubmission based on results from Study 041 and from the Company’s international drug registry study for nmDMD patients receiving Translarna. This meeting is scheduled for March 2024.

The Company has developed Upstaza (eladocagene exuparvovec), a gene therapy used for the treatment of Aromatic L-Amino Acid Decarboxylase (“AADC”) deficiency (“AADC deficiency”), a rare central nervous system (“CNS”)

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PTC Therapeutics, Inc.

Notes to consolidated financial statements (Continued)

December 31, 2023

(In thousands except share and per share amount)

disorder arising from reductions in the enzyme AADC that results from mutations in the dopa decarboxylase gene. In July 2022, the EC approved Upstaza for the treatment of AADC deficiency for patients 18 months and older within the EEA. In November 2022, the Medicines and Healthcare Products Regulatory Agency approved Upstaza for the treatment of AADC deficiency for patients 18 months and older within the United Kingdom. The Company is also preparing a biologics license application (“BLA”) for Upstaza for the treatment of AADC deficiency in the United States and anticipates submitting a BLA to the FDA in March 2024.

The Company holds the rights for the commercialization of Tegsedi® (inotersen) and Waylivra® (volanesorsen) for the treatment of rare diseases in countries in Latin America and the Caribbean pursuant to the Collaboration and License Agreement (the “Tegsedi-Waylivra Agreement”), dated August 1, 2018, by and between the Company and Akcea Therapeutics, Inc. (“Akcea”), a subsidiary of Ionis Pharmaceuticals, Inc. Tegsedi has received marketing authorization in the United States, the European Union (the “EU”) and Brazil for the treatment of stage 1 or stage 2 polyneuropathy in adult patients with hereditary transthyretin amyloidosis (“hATTR amyloidosis”). In August 2021, ANVISA, the Brazilian health regulatory authority, approved Waylivra as the first treatment for familial chylomicronemia syndrome (“FCS”) in Brazil. In December 2022, ANVISA approved Waylivra for the treatment of familial partial lipodystrophy (“FPL”). Waylivra has also received marketing authorization in the EU for the treatment of FCS.

The Company also has a spinal muscular atrophy (“SMA”) collaboration with F. Hoffman-La Roche Ltd and Hoffman-La Roche Inc. (referred to collectively as “Roche”) and the Spinal Muscular Atrophy Foundation (“SMA Foundation”). The SMA program has one approved product, Evrysdi® (risdiplam), which was approved by the FDA in August 2020 for the treatment of SMA in adults and children two months and older and by the EC in March 2021 for the treatment of 5q SMA in patients two months and older with a clinical diagnosis of SMA Type 1, Type 2 or Type 3 or with one to four SMN2 copies. Evrysdi has also received marketing authorization for the treatment of SMA in over 100 countries. In May 2022, the FDA approved a label expansion for Evrysdi to include infants under two months old with SMA. In August 2023, the EC approved an extension of the Evrysdi marketing authorization to include infants under two months old in the EU.

One of the Company’s most advanced clinical stage molecules is sepiapterin. Sepiapterin is a precursor to intracellular tetrahydrobiopterin, which is a critical enzymatic cofactor involved in metabolism and synthesis of numerous metabolic products, for orphan diseases. In May 2023, the Company announced that the primary endpoint was achieved in its registration-directed Phase 3 trial for sepiapterin for phenylketonuria (“PKU”). The primary endpoint of the study was the achievement of statistically-significant reduction in blood Phe level. PTC expects to submit a marketing authorization application (“MAA”) to the EMA for sepiapterin for the treatment of PKU in the EEA in March 2024. Additionally, the Company participated in a pre-NDA meeting with the FDA in the third quarter of 2023. At that meeting, the FDA stated that the sepiapterin clinical safety and efficacy data supported NDA submission for the treatment of pediatric and adult PKU patients. However, the FDA has requested that PTC completes a 26-week nonclinical mouse study to assess sepiapterin carcinogenicity potential prior to NDA submission. Based on the timing to complete this study, PTC expects to submit an NDA to the FDA for sepiapterin for the treatment of PKU no later than the third quarter of 2024 and PTC intends to discuss with the FDA the potential for an earlier submission if PTC is permitted to submit the 26-week mouse study report during the NDA review.

In addition to the Company’s SMA program, the Company’s splicing platform also includes PTC518, which is being developed for the treatment of Huntington’s disease (“HD”). The Company initiated a Phase 2 study of PTC518 for the treatment of HD in the first quarter of 2022, which consists of an initial 12-week placebo-controlled phase focused on safety, pharmacology and pharmacodynamic effects followed by a nine-month placebo-controlled phase focused on PTC518 biomarker effect. In June 2023, the Company announced interim data from the 12-week placebo-controlled phase. The Phase 2 study is actively ongoing outside the United States, while it has been paused within the United States as the

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PTC Therapeutics, Inc.

Notes to consolidated financial statements (Continued)

December 31, 2023

(In thousands except share and per share amount)

FDA requested additional data to allow the Phase 2 study to proceed. The Company expects results from the 12-month interim data from the Phase 2 study of PTC518 for the treatment of HD in the second quarter of 2024. The Company expects to submit a safety data update to the FDA in the second quarter of 2024 to support lifting of the partial clinical hold on the program.

The Company’s ferroptosis and inflammation platform consists of small molecule compounds that target oxidoreductase enzymes that regulate oxidative stress and inflammatory pathways central to the pathology of a number of CNS diseases. The two most advanced molecules in the Company’s ferroptosis and inflammation platform are vatiquinone and utreloxastat. The Company announced topline results from a registration-directed Phase 3 trial of vatiquinone in children and young adults with Friedreich ataxia, called MOVE-FA, in May 2023. While the study did not meet its primary endpoint, vatiquinone treatment did demonstrate significant benefit on key disease subscales, including the upright stability subscale, as well as on other disease relevant endpoints. In the first quarter of 2024, the Company met with the FDA, who expressed willingness to review an NDA for vatiquinone for the treatment of Friedreich ataxia based on the MOVE-FA trial as well as data from the ongoing open label extension study following the MOVE-FA trial, potentially allowing for the submission of an NDA in late 2024. In the first quarter of 2024, the Company also received scientific advice from the EMA on the MOVE-FA trial results, in which the EMA stated that the MOVE-FA data would likely not be sufficient for conditional authorization. The Company initiated a Phase 2 registration directed trial of utreloxastat for amyotrophic lateral sclerosis, or ALS, in the first quarter of 2022. The Company expect topline results from this trial in the fourth quarter of 2024.

In addition, the Company has a pipeline of product candidates and discovery programs that are in early clinical, pre-clinical and research and development stages focused on the development of new treatments for multiple therapeutic areas for rare diseases.

As of December 31, 2023, the Company had an accumulated deficit of approximately $3,283.6 million. The Company has financed its operations to date primarily through the private offerings of convertible senior notes (see Note 7), public and “at the market offerings” of common stock, proceeds from royalty purchase agreements (see Note 2), net proceeds from its borrowings under its credit agreement with Blackstone (see Note 7), private placements of its convertible preferred stock and common stock, collaborations, bank and institutional lender debt, other convertible debt, grant funding and clinical trial support from governmental and philanthropic organizations and patient advocacy groups in the disease area addressed by the Company’s product candidates. The Company has also relied on revenue generated from net sales of Translarna for the treatment of nmDMD in territories outside of the United States since 2014, Emflaza for the treatment of DMD in the United States since 2017 and Upstaza for the treatment of AADC deficiency in the EEA since May 2022. The Company has also relied on revenue associated with milestone and royalty payments from Roche pursuant to the License and Collaboration Agreement (the “SMA License Agreement”) dated as of November 23, 2011, by and among the Company, Roche and, for the limited purposes set forth therein, the SMA Foundation, under its SMA program. The Company expects that cash flows from the sales of its products, together with the Company’s cash, cash equivalents and marketable securities, will be sufficient to fund its operations for at least the next twelve months.

2. Summary of significant accounting policies

Basis of presentation

The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and include all adjustments necessary for the fair presentation of the Company’s financial position for the periods presented.

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December 31, 2023

(In thousands except share and per share amount)

Use of estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Significant estimates in these consolidated financial statements have been made in connection with the calculation of net product sales, royalty revenue, certain accruals related to the Company’s research and development expenses, valuation procedures for liability for sale of future royalties, indefinite lived intangible assets annual impairment assessment, fair value of the contingent consideration, and the provision for or benefit from income taxes. Actual results could differ from those estimates. Changes in estimates are reflected in reported results in the period in which they become known.

Restricted Cash

Restricted cash included in deposits and other assets on the consolidated balance sheet relates to an unconditional, irrevocable and transferable letter of credit that was entered into during the twelve-month period ended December 31, 2019 in connection with obligations under a facility lease for the Company’s leased biologics manufacturing facility in Hopewell Township, New Jersey. The amount of the letter of credit is $7.5 million, is to be maintained for a term of not less than five years and has the potential to be reduced to $3.8 million if after five years from the lease commencement the Company is not in default of its lease. Restricted cash also contains an unconditional, irrevocable and transferable letter of credit that was entered into during June 2022 in connection with obligations for the Company’s new facility lease in Warren, New Jersey. The amount of the letter of credit is $8.1 million and has the potential to be reduced to $4.1 million if after five years the Company is not in default of its lease. Both amounts are classified within deposits and other assets on the consolidated balance sheet due to the long-term nature of the letter of credit. Restricted cash also includes a bank guarantee of $0.6 million denominated in a foreign currency.

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the consolidated balance sheet that sum to the total of the same amounts shown in the statement of cash flows:

End of Beginning of

period- period-

December 31, December 31,

Restricted cash included in deposits and other assets 16,283 16,091

Consolidation

The consolidated financial statements include the accounts of PTC Therapeutics, Inc. and its wholly owned subsidiaries. All inter-company accounts, transactions, and profits have been eliminated in consolidation.

Segment and geographic information

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating and reporting segment.

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December 31, 2023

(In thousands except share and per share amount)

Cash equivalents

The Company considers all highly liquid investments with a maturity of 90 days or less at the time of purchase to be cash equivalents. Cash equivalents are carried at cost which approximates fair value due to their short-term nature.

Marketable securities

The Company’s marketable securities consists of both debt securities and equity investments. The Company considers its investments in debt securities with original maturities of greater than 90 days to be available for sale securities. Securities under this classification are recorded at fair value and unrealized gains and losses within accumulated other comprehensive income. The estimated fair value of the available for sale securities is determined based on quoted market prices or rates for similar instruments. In addition, the cost of debt securities in this category is adjusted for amortization of premium and accretion of discount to maturity. For available for sale debt securities in an unrealized loss position, the Company assesses whether it intends to sell or if it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value. If the criteria are not met, the Company evaluates whether the decline in fair value has resulted from a credit loss or other factors. In making this assessment, management considers, among other factors, the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of the cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded for the credit loss, limited by the amount that the fair value is less than the amortized costs basis. Any impairment that has not been recorded through an allowance for credit losses is recognized in other comprehensive income. For the years ended December 31, 2023 and 2022, no allowance was recorded for credit losses.

Marketable securities that are equity investments are measured at fair value, as it is readily available, and as such are classified as Level 1 assets. Unrealized holding gains and losses for these equity investments are components of other income (expense), net within the consolidated statement of operations.

Concentration of credit risk

The Company’s financial instruments that are exposed to credit risks consist primarily of cash and cash equivalents, available-for-sale marketable securities and accounts receivable. The Company maintains its cash and cash equivalents in bank accounts, which, at times, exceed federally insured limits. The Company has not experienced any credit losses in these accounts and does not believe it is exposed to any significant credit risk on these funds. The Company’s investment policy includes guidelines on the quality of the financial institutions and financial instruments the Company is allowed to invest in, which the Company believes minimizes the exposure to concentration of credit risk.

The Company is subject to credit risk from its accounts receivable related to its product sales. The payment terms are predetermined and the Company evaluates the creditworthiness of each customer or distributor on a regular basis. The Company reserves all uninsured amounts billed directly to a patient until the time of cash receipt as collectability is not reasonably assured at the time the product is received. To date, the Company has not incurred any material credit losses.

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December 31, 2023

(In thousands except share and per share amount)

Fixed assets

Fixed assets are stated at cost. Depreciation is computed starting when the asset is placed into service on a straight-line basis over the estimated useful life of the related asset as follows:

Leasehold improvements Lesser of useful life or lease term

Computer equipment and software 3 years

Machinery and lab equipment 7 years

Furniture and fixtures 7 years

Inventory and cost of product sales

Inventory

Inventories are stated at the lower of cost and net realizable value with cost determined on a first-in, first-out basis by product. The Company capitalizes inventory costs associated with products following regulatory approval when future commercialization is considered probable and the future economic benefit is expected to be realized. Products which may be used in clinical development programs are included in inventory and charged to research and development expense when the product enters the research and development process and no longer can be used for commercial purposes. Inventory used for marketing efforts are charged to selling, general and administrative expense. Amounts related to clinical development programs and marketing efforts are immaterial.

The following table summarizes the components of the Company’s inventory for the periods indicated:

The Company periodically reviews its inventories for excess amounts or obsolescence and writes down obsolete or otherwise unmarketable inventory to its estimated net realizable value. The Company recorded write downs of $12.5 million and $1.7 million for the years ended December 31, 2023 and 2022, respectively, primarily related to adjustments to inventory reserves and product approaching expiration. Additionally, though the Company’s product is subject to strict quality control and monitoring which it performs throughout the manufacturing processes, certain batches or units of product may not meet quality specifications resulting in a charge to cost of product sales. For the years ended December 31, 2023 and December 31, 2022, these amounts were immaterial.

Cost of product sales

Cost of product sales consists of the cost of inventory sold, manufacturing and supply chain costs, storage costs, amortization of the acquired intangible asset, royalty payments associated with net product sales, and royalty payments to collaborative partners associated with royalty revenues and collaboration revenue related to milestones. Production costs are expensed as cost of product sales when the related products are sold or royalty revenues and collaboration revenue milestones are earned.

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December 31, 2023

(In thousands except share and per share amount)

Accumulated other comprehensive income (loss)

Accumulated other comprehensive income (loss) consists of unrealized gains or losses on marketable securities and foreign currency translation adjustments.

Revenue recognition

Net product revenue

The Company’s net product revenue primarily consists of sales of Translarna in territories outside of the U.S. for the treatment of nmDMD and sales of Emflaza in the U.S. for the treatment of DMD. The Company recognizes revenue when its performance obligations with its customers have been satisfied. The Company’s performance obligations are to provide products based on customer orders from distributors, hospitals, specialty pharmacies or retail pharmacies. The performance obligations are satisfied at a point in time when the Company’s customer obtains control of the product, which is typically upon delivery. The Company invoices its customers after the products have been delivered and invoice payments are generally due within 30 to 90 days of the invoice date. The Company determines the transaction price based on fixed consideration in its contractual agreements. Contract liabilities arise in certain circumstances when consideration is due for goods the Company has yet to provide. As the Company has identified only one distinct performance obligation, the transaction price is allocated entirely to product sales. In determining the transaction price, a significant financing component does not exist since the timing from when the Company delivers product to when the customers pay for the product is typically less than one year. Customers in certain countries pay in advance of product delivery. In those instances, payment and delivery typically occur in the same month.

The Company records product sales net of any variable consideration, which includes discounts, allowances, rebates related to Medicaid and other government pricing programs, and distribution fees. The Company uses the expected value or most likely amount method when estimating its variable consideration, unless discount or rebate terms are specified within contracts. The identified variable consideration is recorded as a reduction of revenue at the time revenues from product sales are recognized. These estimates for variable consideration are adjusted to reflect known changes in factors and may impact such estimates in the quarter those changes are known. Revenue recognized does not include amounts of variable consideration that are constrained.

During the years ended December 31, 2023, 2022, and 2021, net product sales in the United States were $255.1 million, $218.3 million, and $187.3 million, respectively, consisting solely of sales of Emflaza, and net product sales outside of the United States were $406.1 million, $316.9 million, and $241.6 million respectively, consisting of sales of Translarna, Tegsedi, Waylivra, and Upstaza. Translarna net product revenues made up $355.8 million, $288.6 million, and $236.0 million of the net product sales outside of the United States for the years ended December 31, 2023, 2022, and 2021, respectively. During the years ended December 31, 2023 and 2022, two countries, the United States and Russia, accounted for at least 10% of the Company’s net product sales, representing $255.1 million and $86.0 million, and $218.3 million and $59.7 million of net product sales, respectively. During the year ended December 31, 2021, only the United States accounted for at least 10% of the Company’s net product sales.

In relation to customer contracts, the Company incurs costs to fulfill a contract but does not incur costs to obtain a contract. These costs to fulfill a contract do not meet the criteria for capitalization and are expensed as incurred. The Company considers any shipping and handling costs that are incurred after the customer has obtained control of the product as a cost to fulfill a promise. Shipping and handling costs associated with finished goods delivered to customers are recorded as a selling expense.

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December 31, 2023

(In thousands except share and per share amount)

Collaboration and royalty revenue

The terms of these agreements typically include payments to the Company of one or more of the following: nonrefundable, upfront license fees; milestone payments; research funding and royalties on future product sales. In addition, the Company generates service revenue through agreements that generally provide for fees for research and development services and may include additional payments upon achievement of specified events.

At the inception of a collaboration arrangement, the Company needs to first evaluate if the arrangement meets the criteria in Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 808 “Collaborative Arrangements” to then determine if ASC Topic 606 is applicable by considering whether the collaborator meets the definition of a customer. If the criteria are met, the Company assesses the promises in the arrangement to identify distinct performance obligations.

For licenses of intellectual property, the Company assesses, at contract inception, whether the intellectual property is distinct from other performance obligations identified in the arrangement. If the licensing of intellectual property is determined to be distinct, revenue is recognized for nonrefundable, upfront license fees when the license is transferred to the customer and the customer can use and benefit from the license. If the licensing of intellectual property is determined not to be distinct, then the license will be bundled with other promises in the arrangement into one distinct performance obligation. The Company needs to determine if the bundled performance obligation is satisfied over time or at a point in time. If the Company concludes that the nonrefundable, upfront license fees will be recognized over time, the Company will need to assess the appropriate method of measuring proportional performance.

For milestone payments, the Company assesses, at contract inception, whether the development or sales-based milestones are considered probable of being achieved. If it is probable that a significant revenue reversal will occur, the Company will not record revenue until the uncertainty has been resolved. Milestone payments that are contingent upon regulatory approval are not considered probable of being achieved until the applicable regulatory approvals or other external conditions are obtained as such conditions are not within the Company’s control. If it is probable that a significant revenue reversal will not occur, the Company will estimate the milestone payments using the most likely amount method. The Company will re-assess the development and sales-based milestones each reporting period to determine the probability of achievement. The Company recognizes royalties from product sales at the later of when the related sales occur or when the performance obligation to which the royalty has been allocated has been satisfied. If it is probable that a significant revenue reversal will not occur, the Company will estimate the royalty payments using the most likely amount method.

The Company recognizes revenue for reimbursements of research and development costs under collaboration agreements as the services are performed. The Company records these reimbursements as revenue and not as a reduction of research and development expenses as the Company has the risks and rewards as the principal in the research and development activities.

For the years ended December 31, 2023, 2022, and 2021, the Company has recognized $100.0 million, $50.1 million, and $55.0 million of collaboration revenue, respectively, related to the SMA License Agreement with Roche.

For the years ended December 31, 2023, 2022 and 2021, the Company has recognized $168.9 million, $113.5 million, and $54.6 million of royalty revenue, respectively, related to Evrysdi.

Manufacturing Revenue

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(In thousands except share and per share amount)

The Company has manufacturing services related to the production of plasmid deoxyribonucleic acid (“DNA”) and adeno-associated virus (“AAV”) vectors for gene therapy applications for external customers. Performance obligations vary but may include manufacturing plasmid DNA and/or AAV vectors, material testing, stability studies, and other services related to material development. The transaction prices for these arrangements are fixed and include amounts stated in the contracts for each promised service. Typically, the performance obligations within a manufacturing contract are highly interdependent, in which case, the Company will combine them into a single performance obligation. The Company has determined that the assets created have no alternative use to the Company, and the Company has an enforceable right to payment for the performance completed to date, therefore revenue related to these services are recognized over time and is measured using an output method based on performance of manufacturing milestones completed to date.

Manufacturing service contracts may also include performance obligations related to project management services or obtaining materials from third parties. The Company has determined that these are separate performance obligations for which revenue is recognized at the point in time the services are performed. For performance obligations related to obtaining third party materials, the Company has determined that it is the principal as the Company has control of the materials and has discretion in setting the price. Therefore, the Company recognizes revenue on a gross basis related to obtaining third party materials.

Certain arrangements require a portion of the contract consideration to be received in advance at the commencement of the contract, and such advance payment is initially recorded as a contract liability. A contract asset may be recognized in the event the Company’s satisfaction of performance obligations outpaces customer billings.

For the year ended December 31, 2023, the Company recognized $7.7 million of manufacturing revenue related to plasmid DNA and AAV vector production for external customers. No manufacturing revenue was recognized for the years ended December 31, 2022 and 2021. As of December 31, 2023, the Company has contract assets of $0.2 million and remaining performance obligations of $0.8 million related to the production of plasmid DNA and AAV vectors for gene therapy applications for external customers. For the period ended December 31, 2022, the Company had remaining performance obligations of $1.4 million and no contracts assets related to plasmid DNA and AAV production for external customers.

Allowance for doubtful accounts

The Company maintains an allowance for estimated losses resulting from the inability of its customers to make required payments. The Company estimates uncollectible amounts based upon current customer receivable balances, the age of customer receivable balances, the customer’s financial condition and current economic trends. The Company also assesses whether an allowance for expected credit losses may be required which includes a review of the Company’s receivables portfolio, which are pooled on a customer basis or country basis. In making its assessment of whether an allowance for credit losses is required, the Company considers its historical experience with customers, current balances, levels of delinquency, regulatory and legal environments, and other relevant current and future forecasted economic conditions. For the years ended December 31, 2023 and 2022, no allowance was recorded for credit losses. The allowance for doubtful accounts was $1.2 million as of December 31, 2023 and $0.3 million as of December 31, 2022. For the years ended December 31, 2023, 2022 and 2021, bad debt expense was $0.9 million, $0.2 million, and $0.1 million, respectively.

Liability for sale of future royalties

On July 17, 2020, the Company, RPI Intermediate Finance Trust (“RPI”), and, for the limited purposes set forth in the agreement, Royalty Pharma PLC, entered into a royalty purchase agreement (the “Original Royalty Purchase

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December 31, 2023

(In thousands except share and per share amount)

Agreement”). Pursuant to the Original Royalty Purchase Agreement, the Company sold to RPI 42.933% (the “Original Assigned Royalty Rights”) of the Company’s right to receive sales-based royalty payments (the “Royalty”) on worldwide net sales of Evrysdi and any other product developed pursuant to the License and Collaboration Agreement (the “License Agreement”), dated as of November 23, 2011, by and among the Company, Roche and, for the limited purposes set forth therein, the SMA Foundation under the SMA program. In consideration for the sale of the Original Assigned Royalty Rights, RPI paid the Company $650.0 million in cash consideration. The Company has retained a 57.067% interest in the Royalty and all economic rights to receive the remaining potential regulatory and sales milestone payments under the License Agreement, which remaining milestone payments equal $150.0 million in the aggregate as of December 31, 2023. The Original Royalty Purchase Agreement was set to terminate 60 days following the earlier of the date on which Roche is no longer obligated to make any payments of the Royalty pursuant to the License Agreement and the date on which RPI has received $1.3 billion in respect of the Original Assigned Royalty Rights.

Pursuant to the guidance in ASC 470-10-25-2, the Company determined that the $650.0 million cash consideration obtained pursuant to the Original Royalty Purchase Agreement should be classified as debt and recorded it as “liability for sale of future royalties-current” and “liability for sale of future royalties-noncurrent” on the Company’s consolidated balance sheet based on the timing of the expected payments to be made to RPI at the time of the transaction. The liability was subsequently amortized using the effective interest method over the life of the arrangement, in accordance with the respective guidance, utilizing the prospective method to account for subsequent changes in the estimated future payments to be made to RPI.

On October 18, 2023, the Company, Royalty Pharma Investments 2019 ICAV (“Royalty Pharma”), and, for the limited purposes set forth in the agreement, Royalty Pharma plc, entered into an Amended and Restated Royalty Purchase Agreement (the “A&R Royalty Purchase Agreement”), which amends and restates in its entirety the Original Royalty Purchase Agreement. Pursuant to the A&R Royalty Purchase Agreement, the Company has sold or agreed to sell to Royalty Pharma certain portions of the Company’s remaining Royalty on worldwide net sales of Evrysdi and any other product (the “Products”) developed pursuant to the SMA License Agreement (all such retained Royalty rights of the Company, the “Retained Royalty Rights,” and all such Royalty rights that are sold to Royalty Pharma pursuant to the A&R Royalty Purchase Agreement, the “A&R Assigned Royalty Rights”). At closing, Royalty Pharma paid the Company $1.0 billion in cash consideration for 38.0447% of the Company’s Retained Royalty Rights (which is in addition to the 42.9330% assigned to Royalty Pharma in connection with the Original Royalty Purchase Agreement, for a total of 80.9777% of the total Royalty) until such time as Royalty Pharma has received payments in respect of the Original Assigned Royalty Rights equal to $1.3 billion in the aggregate, and thereafter 66.6667% of the total Royalty. In addition, the Company may sell to Royalty Pharma the remainder of the Company’s Retained Royalty Rights in exchange for an aggregate of $500.0 million in additional cash consideration after the closing of the A&R Royalty Purchase Agreement, less royalties received in respect of the Retained Royalty Rights put to Royalty Pharma, which will be payable by Royalty Pharma pursuant to five put options held by the Company that are exercisable at the Company’s option between January 1, 2024 and December 31, 2025. If the Company exercises two or fewer of the put options, Royalty Pharma may exercise a call option during the period from and after January 1, 2026 until and including March 31, 2026 for up to 50% of the remainder of the Company’s Retained Royalty Rights less amounts exercised by the Company via its put options at a purchase price that is proportional to the purchase price of the Company’s unexercised put options. Royalty Pharma’s exercise of the call option would result in Royalty Pharma owning 90.4888% of the total Royalty until such time as Royalty Pharma has received payments in respect of the Original Assigned Royalty Rights equal to $1.3 billion in the aggregate, and thereafter 83.3333% of the total Royalty. The A&R Royalty Purchase Agreement will terminate 60 days following the date on which Roche is no longer obligated to make any payments of the Royalty pursuant to the License Agreement.

The change in rights and obligations from the A&R Royalty Purchase Agreement resulted in a change in the terms of the liability for sale of future royalties, which was evaluated by the Company in accordance with ASC 470-50, Debt —

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December 31, 2023

(In thousands except share and per share amount)

Modifications and Extinguishments. The Company determined that the present value of the cash flows under the A&R Royalty Purchase Agreement were substantially different from the present value of the cash flows under the Original Royalty Purchase Agreement. This resulted in the derecognition of the old liability for sale of future royalties and the new liability for sale of future royalties being recorded at fair value, which was determined to be $1,809.9 million as of the date of the A&R Royalty Purchase Agreement. This resulted in an extinguishment loss of $44.9 million, which was recorded within loss on extinguishment of debt, within the Company’s statement of operations.

The fair value for the new liability for sale of future royalties on the date of the A&R Royalty Purchase Agreement was based on the Company’s estimates of future royalties expected to be paid to Royalty Pharma over the life of the arrangement, which was determined using forecasts from market data sources, which are considered Level 3 inputs. The liability is being amortized using the effective interest method over the life of the arrangement, in accordance with ASC 470 and ASC 835. The initial annual effective interest rate was determined to be 10.8%. The Company utilizes the prospective method to account for subsequent changes in the estimated future payments to be made to Royalty Pharma and updates the effective interest rate on a quarterly basis. Issuance costs related to the transaction were determined to be immaterial. Refer to Note 7 for further details.

PTCT US Equity

PTCT · 10-K · period ended 2023-12-31

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

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

Item 8. Financial Statements and Supplementary Data

PTCT US Equity☆

PTCT · 10-K · period ended 2023-12-31

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

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

Item 8. Financial Statements and Supplementary Data

PTCT US Equity