PTC THERAPEUTICS, INC.

Previous wording

Sephience (sepiapterin) is a product for the treatment of phenylketonuria, or PKU, a rare inherited metabolic disease characterized by the body’s inability to break down an essential amino acid called phenylalanine, and which can result in neurological and other symptoms. In June 2025, Sephience was granted marketing authorization by the European Commission, or EC, for the treatment of children and adults living with PKU within the European Economic Area, or EEA. In July 2025, Sephience was approved by the U.S. Food and Drug Administration, or FDA, for the treatment of pediatric and adult patients living with PKU in the United States age one month and above. In December 2025, Sephience was approved by the Japanese Ministry of Health, Labor and Welfare, or MHLW, for the treatment of children and adults living with PKU in Japan, where the label includes individuals of all ages and the full spectrum of disease severity. In February 2026, Sephience was approved by ANVISA, the Brazilian health regulatory authority, for the treatment of children and adults living with PKU in Brazil. Sephience is also approved in additional geographies. During the three months ended June 30, 2026, we recognized $151.3 million in net sales of Sephience.

Current wording

Sephience (sepiapterin) is a product for the treatment of phenylketonuria, or PKU, a rare inherited metabolic disease characterized by the body’s inability to break down an essential amino acid called phenylalanine, and which can result in neurological and other symptoms. In June 2025, Sephience was granted marketing authorization by the European Commission, or EC, for the treatment of children and adults living with PKU within the European Economic Area, or EEA. In July 2025, Sephience was approved by FDA for the treatment of pediatric and adult patients living with PKU in the United States age one month and above. In December 2025, Sephience was approved by the Japanese Ministry of Health, Labor and Welfare for the treatment of children and adults living with PKU in Japan, where the label includes individuals of all ages and the full spectrum of disease severity. In February 2026, Sephience was approved by ANVISA,

Previous wording

We have two products, Translarna™ (ataluren) and Emflaza® (deflazacort), for the treatment of Duchenne muscular dystrophy, or DMD, a rare, life-threatening disorder. While Translarna previously had conditional approval in the EEA, in March 2025, the EC adopted the negative opinion of the Committee of Medicinal Products for Human Use, or CHMP, of the European Medicines Agency, or EMA, to not renew the conditional marketing authorization of Translarna for the treatment of nonsense mutation Duchenne muscular dystrophy, or nmDMD. However, the EC indicated that individual countries within the European Union, or EU, can leverage Articles 117(3) and 5(1) of the EU Directive 2001/83 to allow continued commercial use of Translarna.

Current wording

We have two products, Translarna™ (ataluren) and Emflaza® (deflazacort), for the treatment of Duchenne muscular dystrophy, or DMD, a rare, life-threatening disorder. While Translarna previously had conditional approval in the EEA, in March 2025, the EC adopted the negative opinion of the Committee for Medicinal Products for Human Use, or CHMP, of the European Medicines Agency, or EMA, to not renew the conditional marketing authorization of Translarna for the treatment of nonsense mutation Duchenne muscular dystrophy, or nmDMD. However, the EC indicated that individual countries within the European Union, or EU, can leverage Articles 117(3) and 5(1) of the EU Directive 2001/83 to allow continued commercial use of Translarna.

Previous wording

Translarna has marketing authorization in additional geographies outside of the EEA, though the EC adoption of the CHMP negative opinion and the withdrawal of the Translarna NDA in the United States may affect future reauthorizations. During the three months ended June 30, 2026, we recognized $42.2 million in net sales for Translarna. Emflaza is approved in the United States for the treatment of DMD in patients two years and older. During the three months ended June 30, 2026, we recognized $24.6 million in net sales for Emflaza.

Current wording

Translarna has marketing authorization in additional geographies outside of the EEA, though the EC adoption of the CHMP negative opinion and the withdrawal of the Translarna NDA in the United States may affect future reauthorizations. During the three months ended September 30, 2026, we recognized $48.5 million in net sales for Translarna. Emflaza is approved in the United States for the treatment of DMD in patients two years and older. During the three months ended September 30, 2026, we recognized $25.1 million in net sales for Emflaza.

Previous wording

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 for the treatment of DMD in patients five years and older, which expired in February 2024. With the expiration of this orphan drug exclusivity, we have seen an increase in competition from generics, which has, and we expect will continue to have, a 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 expired in June 2026.

Current wording

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, when commercializing Emflaza for the treatment of DMD in patients five years and older, which expired in February 2024, and for the treatment of DMD in patients two years of age to less than five, which expired in June 2026. With the expiration of this orphan drug exclusivity, we have seen an increase in competition from generics, which has, and we expect will continue to have, a negative impact on Emflaza net product revenue.

Previous wording

Upstaza/Kebilidi 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. In November 2024, the FDA granted accelerated approval of our gene therapy for the treatment of children and adults with AADC deficiency, which is marketed with the brand name Kebilidi in the United States.

Current wording

Upstaza/Kebilidi is a gene therapy for the treatment of Aromatic L Amino Acid 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. In November 2024, the FDA granted accelerated approval of our gene therapy for the treatment of children and adults with AADC deficiency, which is marketed with the brand name Kebilidi in the United States.

Previous wording

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, 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. Waylivra has also received marketing authorization in the EU for the treatment of FCS. In December 2022, ANVISA approved Waylivra for the treatment of familial partial lipodystrophy.

Current wording

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 dated August 1, 2018, by and between us and Akcea Therapeutics, Inc., a subsidiary of Ionis Pharmaceuticals, Inc. Tegsedi has received marketing authorization in the United States, 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.

Previous wording

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 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.

Current wording

We also have a spinal muscular atrophy, or SMA, collaboration with F. Hoffmann-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 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.

Previous wording

In November 2024, we entered into a License and Collaboration Agreement with Novartis Pharmaceuticals Corporation, or Novartis, relating to our votoplam program, or the Novartis Agreement, which included related molecules. While Novartis has taken over responsibility for the further development of the votoplam program, we continue to collaborate with Novartis on next steps. In May 2025, we announced that the Phase 2 study of votoplam met its primary endpoints of blood HTT lowering and safety. The results on the full study population are consistent with the previously reported evidence of dose-dependent HTT lowering, favorable safety profile and early signals of dose-dependent clinical effect at 12 months in Stage 2 patients. In addition, at 24 months of treatment, there were continued trends of dose-dependent favorable clinical effect relative to a propensity-matched natural history cohort as well as dose-dependent NfL lowering. In April 2026, Novartis announced that it had commenced the global Phase 3 clinical trial, which is expected to enroll approximately 770 individuals with early symptomatic disease, randomized 3:2 to receive votoplam 10 milligrams or placebo, and includes an interim analysis. Also in April 2026, we reported positive topline results from the 24-month interim analysis of the PIVOT-HD long-term extension study, with favorable dose-dependent effects on disease progression for Stage 2 HD patients following 24 months of votoplam treatment compared to an external natural history cohort, with 52% slowing of disease progression on the Composite Unified Huntington’s Disease Rating Scale at the 10 milligram dose level. While the Phase 3 clinical trial remains the base case for votoplam approval, we are working with Novartis to finalize a plan to engage with FDA to discuss the 24-month results in the second half of 2026.

Current wording

In November 2024, we entered into a License and Collaboration Agreement with Novartis Pharmaceuticals Corporation, or Novartis, relating to our votoplam program, or the Novartis Agreement, which included related molecules. While Novartis has taken over responsibility for the further development of the votoplam program, we continue to collaborate with Novartis on next steps. In May 2025, we announced that the Phase 2 study of votoplam met its primary endpoints of blood HTT lowering and safety. The results on the full study population are consistent with the previously reported evidence of dose-dependent HTT lowering, favorable safety profile and early signals of dose-dependent clinical effect at 12 months in Stage 2 patients. In addition, at 24 months of treatment, there were continued trends of dose-dependent favorable clinical effect relative to a propensity-matched natural history cohort as well as dose-dependent Neurofilament light lowering. In April 2026, Novartis announced that it had commenced the global Phase 3 clinical trial, which is expected to enroll approximately 770 individuals with early symptomatic disease, randomized 3:2 to receive votoplam 10 milligrams or placebo, and includes an interim analysis. Also in April 2026, we reported positive topline results from the 24-month interim analysis of the PIVOT-HD long-term extension study, with favorable dose-dependent effects on disease progression for Stage 2 HD patients following 24 months of votoplam treatment compared to an external natural history cohort, with 52% slowing of disease progression on the Composite Unified Huntington’s Disease Rating Scale at the 10 milligram dose level. While the Phase 3 clinical trial remains the base case for votoplam approval, we are working with Novartis to finalize a plan to engage with FDA to discuss the 24-month results. Due to FDA scheduling, a Type C meeting to discuss votoplam Phase 2 data and potential accelerated approval path is scheduled for the first quarter of 2027.

Previous wording

Our inflammation and ferroptosis 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 and non-CNS diseases. The most advanced molecule in our inflammation and ferroptosis platform is vatiquinone. We announced topline results from a registration-directed Phase 3 trial of vatiquinone in children and young adults with Friedreich’s ataxia, or FA, called MOVE-FA, in May 2023. While the trial 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 October 2024, we announced that the pre-specified endpoint for two different FA long-term extension studies was met, with statistically significant evidence of durable treatment benefit on disease progression. In December 2024, we submitted an NDA to the FDA for vatiquinone for the treatment of children and adults living with FA. In August 2025, the FDA issued a complete response letter related to the NDA stating that substantial evidence of efficacy was not demonstrated for vatiquinone and that an additional adequate and well-controlled study would be needed to support NDA resubmission. We met with the FDA in the fourth quarter of 2025 to discuss the vatiquinone development program, at which time the FDA suggested an additional study be conducted to support NDA resubmission. In April 2026, we again met with FDA to discuss the design of a new trial to provide additional data to support NDA resubmission. Based on the meeting discussion and written feedback, we plan to initiate the PROVE-FA open label study using matched natural history control in the third quarter of 2026. This study is expected to enroll approximately 120 patients ages 7 to 21 and the study primary endpoint is the change in mFARS from baseline to month 24.

Current wording

was met, with statistically significant evidence of durable treatment benefit on disease progression. In December 2024, we submitted an NDA to the FDA for vatiquinone for the treatment of children and adults living with FA. In August 2025, the FDA issued a complete response letter related to the NDA stating that substantial evidence of efficacy was not demonstrated for vatiquinone and that an additional adequate and well-controlled study would be needed to support NDA resubmission. We met with the FDA in the fourth quarter of 2025 to discuss the vatiquinone development program, at which time the FDA suggested an additional study be conducted to support NDA resubmission. In April 2026, we again met with FDA to discuss the design of a new trial to provide additional data to support NDA resubmission. Based on the meeting discussion and written feedback, in the third quarter of 2026 we initiated the PROVE-FA open label study using matched natural history control. This study is expected to enroll approximately 120 patients ages 7 to 21 and the study primary endpoint is the change in mFARS from baseline to month 24.

Previous wording

During the quarter ended June 30, 2026, we initiated a Phase 1 study of PTC612, our oral NLRP3 inhibitor, and completed several of the single and multiple ascending dose treatment cohorts. Notably, this healthy volunteer study includes a cohort of individuals with obesity and cardiovascular disease, which we expect will provide an early view of pharmacokinetics and pharmacodynamics. We also expect to initiate a Phase 2a study of PTC844, our next-generation DHODH inhibitor, in

Current wording

In the second quarter of 2026, we initiated a Phase 1 study of PTC612, our oral NLRP3 inhibitor, and completed several of the single and multiple ascending dose treatment cohorts. Notably, this healthy volunteer study includes a cohort of individuals with obesity and cardiovascular disease, which we expect will provide an early view of pharmacokinetics and pharmacodynamics.

Previous wording

the third quarter of 2026. The PTC844 study will be a 12-week pharmacokinetics and pharmacodynamics study in which we will assess treatment effect on biomarkers related to T-cell and B-cell immunity. We expect that the results of this study will help inform the ultimate target indications for PTC844.

Current wording

In the third quarter of 2026, we also initiated a Phase 2a study of PTC844, our next-generation DHODH inhibitor. The PTC844 study will be a 12-week pharmacokinetics and pharmacodynamics study in which we will assess treatment effect on biomarkers related to T-cell and B-cell immunity. We expect that the results of this study will help inform the ultimate target indications for PTC844.

Previous wording

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. Our revenues were primarily generated from sales of Sephience for the treatment of PKU in the U.S. and EEA, 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 early access programs, or EAP, programs or through similar styled programs, and from sales of Emflaza forthe treatment of DMD in the United States. There is a substantial risk that as a result of the EC’s adoption of the CHMP’s negative opinion we will lose a significant portion of our ability to generate revenue from sales of Translarna in the EEA. We also generated revenue from sales of Upstaza/Kebilidi for the treatment of AADC deficiency in the EEA and in the U.S., 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 and we have recognized license revenues related to performance obligations completed pursuant to the Novartis Agreement.

Current wording

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. Our revenues were primarily generated from sales of Sephience for the treatment of PKU in the U.S. and EEA, 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 early access programs, or EAPs, or through similar styled programs, and from sales of Emflaza forthe treatment of DMD in the United States. There is a substantial risk that as a result of the EC’s adoption of the CHMP’s negative opinion we will lose a significant portion of our ability to generate revenue from sales of Translarna in the EEA. We also generated revenue from sales of Upstaza/Kebilidi for the treatment of AADC deficiency in the EEA and in the U.S., 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 and we have recognized license revenues related to performance obligations completed pursuant to the Novartis Agreement.

Previous wording

In June 2024, we entered into an amendment with Royalty Pharma Investments 2019 ICAV, or Royalty Pharma, and Royalty Pharma plc, to the Amended and Restated Royalty Purchase Agreement, dated October 18, 2023, or the A&R Royalty Purchase Agreement, which amends and restated in its entirety the Royalty Purchase Agreement with RPI Intermediate Finance Trust, or the Immediate Finance Trust, or the Original Purchase Agreement, and we exercised our first put option in exchange for $241.8 million in cash consideration. In December 2025, we, Royalty Pharma, and, for the limited purposes set forth in Amendment No. 2 (as defined below), Royalty Pharma plc, entered into an Amendment No. 2 to Amended and Restated Royalty Purchase Agreement, or Amendment No. 2, which amends that certain A&R Royalty Purchase Agreement, as amended. Under Amendment No. 2, we sold to Royalty Pharma a certain portion of our right to receive sales-based royalty payments on worldwide net sales of Roche’s Evrysdi® (risdiplam) product and any other product developed pursuant to the License and Collaboration Agreement, dated as of November 23, 2011, by and among us, F. Hoffman-La Roche Ltd, Hoffman-La Roche Inc., together with F. Hoffman-La Roche Ltd, Roche, and, for the limited purposes set forth therein, the Spinal Muscular Atrophy Foundation, such payments, the Royalty. Pursuant to Amendment No. 2, on December 29, 2025, we sold to Royalty Pharma its retained interest in the Royalty in exchange for $240.0 million in upfront cash consideration, and three potential additional cash purchase price payments of $20.0 million each conditioned upon receipt by Royalty Pharma of more than $347.0 million of Assigned Royalty Payments (as defined in the A&R Royalty Purchase Agreement) in respect of Calendar Year Net Sales (as defined in the A&R Royalty Purchase Agreement) arising in 2027, $363.0 million of Assigned Royalty Payments in respect of Calendar Year Net Sales arising in 2028, and $379.0 million of Assigned Royalty Payments in respect of Calendar Year Net Sales arising in 2029, respectively. The retained interest sold by us to Royalty Pharma purs uant to the Amendment No. 2 is equal to 9.5111% of the Royalty before the 2020 Assigned Royalty Cap (as defined in the A&R Royalty Purchase Agreement) has been met,

Current wording

Intermediate Finance Trust, and we exercised our first put option in exchange for $241.8 million in cash consideration. In December 2025, we, Royalty Pharma, and, for the limited purposes set forth in Amendment No. 2 (as defined below), Royalty Pharma plc, entered into an Amendment No. 2 to Amended and Restated Royalty Purchase Agreement, or Amendment No. 2, which amends that certain A&R Royalty Purchase Agreement, as amended. Under Amendment No. 2, we sold to Royalty Pharma a certain portion of our right to receive sales-based royalty payments on worldwide net sales of Roche’s Evrysdi® (risdiplam) product and any other product developed pursuant to the License and Collaboration Agreement, dated as of November 23, 2011, by and among us, F. Hoffman-La Roche Ltd, Hoffman-La Roche Inc., together with F. Hoffmann-La Roche Ltd, Roche, and, for the limited purposes set forth therein, the Spinal Muscular Atrophy Foundation, such payments, the Royalty. Pursuant to Amendment No. 2, on December 29, 2025, we sold to Royalty Pharma its retained interest in the Royalty in exchange for $240.0 million in upfront cash consideration, and three potential additional cash purchase price payments of $20.0 million each conditioned upon receipt by Royalty Pharma of more than $347.0 million of Assigned Royalty Payments (as defined in the A&R Royalty Purchase Agreement) in respect of Calendar Year Net Sales (as defined in the A&R Royalty Purchase Agreement) arising in 2027, $363.0 million of Assigned Royalty Payments in respect of Calendar Year Net Sales arising in 2028, and $379.0 million of Assigned Royalty Payments in respect of Calendar Year Net Sales arising in 2029, respectively. The retained interest sold by us to Royalty Pharma purs uant to the Amendment No. 2 is equal to 9.5111% of the Royalty before the 2020 Assigned Royalty Cap (as defined in the A&R Royalty Purchase Agreement) has been met, and 16.6666% of the Royalty from and after such time as the 2020 Assigned Royalty Cap has been met. As a result of the sale, Royalty Pharma owns 100% of the Royalty and we own 0% of the Royalty.

Previous wording

In November 2024, we entered into the Novartis Agreement relating to our votoplam HD program which includes related molecules. Novartis is responsible for all other development of licensed compounds and licensed products and the manufacture and commercialization of licensed compounds and licensed products worldwide. While Novartis has taken over responsibility for the further development of the votoplam program, we continue to collaborate with Novartis on next steps. Under the Novartis Agreement, and upon the closing of the transaction contemplated by the Novartis Agreement in January 2025, we received an upfront payment of $1.0 billion on the effective date and we are eligible to receive up to $1.9 billion in development, regulatory and sales milestones, a 40% share of U.S. profits and losses, and tiered double-digit royalties on ex-U.S. sales. We have also recognized revenue associated with milestone payments from Novartis pursuant to the Novartis Agreement. In April 2026, Novartis notified us that it had initiated the first Phase 3 clinical trial for a Licensed Product (as defined in the Novartis Agreement), which pursuant to the Novartis Agreement, triggered a $50.0 million milestone payment to us. The $50.0 million development milestone is recorded as collaboration and license revenue for the three and six months ended June 30, 2026.

Current wording

In November 2024, we entered into the Novartis Agreement relating to our votoplam HD program which includes related molecules. Novartis is responsible for all other development of licensed compounds and licensed products and the manufacture and commercialization of licensed compounds and licensed products worldwide. While Novartis has taken over responsibility for the further development of the votoplam program, we continue to collaborate with Novartis on next steps. Under the Novartis Agreement, and upon the closing of the transaction contemplated by the Novartis Agreement in January 2025, we received an upfront payment of $1.0 billion on the effective date and we are eligible to receive up to $1.9 billion in development, regulatory and sales milestones, a 40% share of U.S. profits and losses, and tiered double-digit royalties on ex-U.S. sales. We have also recognized revenue associated with milestone payments from Novartis pursuant to the Novartis Agreement. In April 2026, Novartis notified us that it had initiated the first Phase 3 clinical trial for a Licensed Product (as defined in the Novartis Agreement), which pursuant to the Novartis Agreement, triggered a $50.0 million milestone payment to us. The $50.0 million development milestone is recorded as collaboration and license revenue for the nine months ended September 30, 2026.

Previous wording

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. During the three and six months ended June 30, 2026, we did not issue or sell any shares of common stock pursuant to the Sales Agreement. 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 June 30, 2026.

Current wording

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. During the three and nine months ended September 30, 2026, we did not issue or sell any shares of common stock pursuant to the Sales Agreement. 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 September 30, 2026.

Previous wording

Following the issuance of the 2031 Convertible Notes, we used approximately $328.8 million of the net proceeds of the 2031 Convertible Notes to repurchase for cash $222.0 million aggregate principal amount of our outstanding 1.50% convertible senior notes due September 15, 2026, or the 2026 Convertible Notes, pursuant to privately negotiated transactions with certain holders entered into concurrently with the pricing of the offering of the 2031 Convertible Notes. Cash interest payments on the 2026 Convertible Notes were payable on a semi-annual basis in arrears, which will require remaining funding of $0.4 million. The 2026 Convertible Notes are currently convertible at the option of the holders and will mature and become due and payable on September 15, 2026, unless earlier repurchased or converted.

Current wording

Following the issuance of the 2031 Convertible Notes, we used approximately $328.8 million of the net proceeds of the 2031 Convertible Notes to repurchase for cash $222.0 million aggregate principal amount of our outstanding 1.50% convertible senior notes due September 15, 2026, or the 2026 Convertible Notes, pursuant to privately negotiated transactions with certain holders entered into concurrently with the pricing of the offering of the 2031 Convertible Notes.

Previous wording

As of the quarter ended June 30, 2026, aggregate Sephience global net sales in the prior four consecutive quarters exceeded $250.0 million, which, pursuant to the Agreement and Plan of Merger, dated as of May 6, 2020, or the Censa Merger Agreement, by and among us and Censa Pharmaceuticals, Inc., or Censa, triggered a $30.0 million net sales milestone to the former Censa securityholders. This milestone payment was recorded in accounts payable and accrued expenses on our consolidated balance sheet as of June 30, 2026.

Current wording

In the three months ended June 30, 2026, aggregate Sephience global net sales in the prior four consecutive quarters exceeded $250.0 million, which, pursuant to the Agreement and Plan of Merger, dated as of May 6, 2020, or the Censa Merger Agreement, by and among us and Censa Pharmaceuticals, Inc., or Censa, triggered a $30.0 million net sales milestone to the former Censa securityholders. This milestone payment was recorded in accounts payable and accrued expenses and intangible assets on our consolidated balance sheet as of September 30, 2026. In the three months ended September 30, 2026, aggregate Sephience global net sales in the prior four consecutive quarters exceeded $500.0 million, which, pursuant to the Censa Merger Agreement, triggered a $50.0 million net sales milestone payment to the former Censa securityholders. This milestone was recorded in accounts payable and accrued expenses and intangible assets on our consolidated balance sheet as of September 30, 2026.

Previous wording

As of June 30, 2026, we had an accumulated deficit of $2,883.5 million. We had net income of $80.7 million and $801.7 million for the six months ended June 30, 2026 and 2025, respectively.

Current wording

As of September 30, 2026, we had an accumulated deficit of $2,935.2 million. We had net income of $29.0 million and $817.6 million for the nine months ended September 30, 2026 and 2025, respectively.

Previous wording

*Net product revenues.*Our net product revenues primarily consist of sales of Sephience for the treatment of PKU. Our net product revenues also consist 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. We recognize revenue when performance obligations with customers have been satisfied and if it is probable that a significant revenue reversal will not occur. 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.

Current wording

*Net product revenues.*Our net product revenues primarily consist of sales of Sephience for the treatment of PKU. Our net product revenues also consist 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. We recognize revenue when performance obligations with customers have been satisfied and if it is probable that a significant revenue reversal will not occur. 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

Previous wording

During the three and six months ended June 30, 2026 and 2025, net product revenues consisted of the following:

Current wording

During the three and nine months ended September 30, 2026 and 2025, net product revenues consisted of the following:

Previous wording

Disaggregated net product revenues by country for the three and six months ended June 30, 2026 and 2025, are as follows:

Current wording

Disaggregated net product revenues by country for the three and nine months ended September 30, 2026 and 2025, are as follows:

Previous wording

For three and six months ended June 30, 2026, three of our distributors each accounted for over 10% of our net product sales. For three and six months ended June 30, 2025, three and two of our distributors, respectively, each accounted for over 10% of our net product sales.

Current wording

For the three and nine months ended September 30, 2026, three of our distributors each accounted for over 10% of our net product sales. For the three and nine months ended September 30, 2025, four and three of our distributors, respectively, each accounted for over 10% of our net product sales.

Previous wording

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.

Current wording

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

Previous wording

*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 June 30, 2026, we had recognized a total of $310.0 million in milestone payments and $907.7 million in royalties on net sales pursuant to the SMA License Agreement. As of June 30, 2026, there are no remaining research and development event milestones that we can receive. The remaining potential sales milestones as of June 30, 2026 are $150.0 million upon achievement of certain sales events.

Current wording

*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 September 30, 2026, we had recognized a total of $310.0 million in milestone payments and $989.4 million in royalties on net sales pursuant to the SMA License Agreement. As of September 30, 2026, there are no remaining research and development event milestones that we can receive. The remaining potential sales milestones as of September 30, 2026 are $150.0 million upon achievement of certain sales events.

Previous wording

For the three and six months ended June 30, 2026 and 2025, we did not recognize collaboration revenue related to the SMA License Agreement with Roche.

Current wording

For the three and nine months ended September 30, 2026 and 2025, we did not recognize collaboration revenue related to the SMA License Agreement with Roche.

Previous wording

For the three and six months ended June 30, 2026, we recognized $71.1 million and $117.9 million of royalty revenue, respectively, related to Evrysdi. For the three and six months ended June 30, 2025, we recognized $57.6 million and $94.0 million of royalty revenue, respectively, related to Evrysdi.

Current wording

For the three and nine months ended September 30, 2026, we recognized $81.7 million and $199.6 million of royalty revenue, respectively, related to Evrysdi. For the three and nine months ended September 30, 2025, we recognized $70.8 million and $164.8 million of royalty revenue, respectively, related to Evrysdi.

Previous wording

Novartis Collaboration for**votoplam HD. In November 2024, we entered into the Novartis Agreement with Novartis related to our votoplam HD program. Upon the closing of the transaction contemplated by the Novartis Agreement in January 2025, we received an upfront payment of $1.0 billion on the effective date and are eligible to receive up to $1.9 billion in development, regulatory and sales milestones, a 40% share of U.S. profits and losses, and tiered double-digit royalties on ex-U.S. sales. During the three and six months ended June 30, 2026, we recognized $50.6 million and $50.7 million in license revenues, respectively, primarily related to a development milestone pursuant to our Novartis Agreement for Novartis’s initiation of the first Phase 3 clinical trial for a Licensed Product (as defined in the Novartis Agreement), which triggered a $50.0 million milestone payment to us. During the three and six months ended June 30, 2025, we recognized $2.9 million and $992.7 million in license revenues, respectively, related to performance obligations completed pursuant to the Novartis Agreement. Collaboration and license revenue during the three months ended June 30, 2025, was partially offset by $3.5 million related to a refund for a prior collaboration arrangement in relation to votoplam.

Current wording

Novartis Collaboration for**votoplam HD. In November 2024, we entered into the Novartis Agreement with Novartis related to our votoplam HD program. Upon the closing of the transaction contemplated by the Novartis Agreement in January 2025, we received an upfront payment of $1.0 billion on the effective date and are eligible to receive up to $1.9 billion in development, regulatory and sales milestones, a 40% share of U.S. profits and losses, and tiered double-digit royalties on ex-U.S. sales. During the three months ended September 30, 2026, we recognized $0.2 million in revenues related to work performed for Novartis. During the nine months ended September 30, 2026, we recognized $51.0 million in license revenues, primarily related to a development milestone pursuant to our Novartis Agreement for Novartis’s initiation of the first Phase 3 clinical trial for a Licensed Product (as defined in the Novartis Agreement), which triggered a $50.0 million milestone payment to us. During the three and nine months ended September 30, 2025, we recognized $9.3 million and $1.0 billion in license revenues, respectively, related to performance obligations completed pursuant to the Novartis Agreement. Collaboration and license revenue during the nine months ended September 30, 2025, was partially offset by $3.5 million related to a refund for a prior collaboration arrangement in relation to votoplam.

Previous wording

The following table provides research and development expense for our most advanced principal product development programs, for the three and six months ended June 30, 2026 and 2025.

Current wording

The following table provides research and development expense for our most advanced principal product development programs, for the three and nine months ended September 30, 2026 and 2025.

Previous wording

For the three and six months ended June 30, 2026, compared to the three and six months ended June 30, 2025, the changes reflect progressing through different phases of studies as we continue to focus our resources on our differentiated, high potential research and development programs. The decrease is primarily due to a decrease in costs relating to Global DMD, Gene Therapy, Splicing platform, Inflammation & Ferroptosis platform, and Sephience related development.

Current wording

For the three and nine months ended September 30, 2026, compared to the three and nine months ended September 30, 2025, the changes reflect progressing through different phases of studies as we continue to focus our resources on our differentiated, high potential research and development programs. For the three months ended September 30, 2026, compared to the three months ended September 30, 2025, the increase is primarily due to an increase in costs relating to Inflammation and Ferroptosis platform and Gene Therapy. For the nine months ended September 30, 2026, compared to the nine months ended September 30, 2025, the decrease is primarily due to a decrease in costs relating to Global DMD, Gene Therapy, Inflammation and Ferroptosis platform, and Sephience related development.

Previous wording

For the three and six months ended June 30, 2026, compared to the three and six months ended June 30, 2025, the increase in research expenses primarily related to increased investment in research programs and advancement of the clinical pipeline.

Current wording

For the three and nine months ended September 30, 2026, compared to the three and nine months ended September 30, 2025, the increase in research expenses primarily related to increased investment in research programs and advancement of the clinical pipeline.

Previous wording

For the three and six months ended June 30, 2026, compared to the three and six months ended June 30, 2025, the increase in payroll, benefits, and share-based stock compensation expenses primarily related to an increase in share-based stock compensation, and increases in salaries due to annual merit increases for the three and six months ended June 30, 2026 compared to the three and six months ended June 30, 2025.

Current wording

For the three and nine months ended September 30, 2026, compared to the three and nine months ended September 30, 2025, the increase in payroll, benefits, and share-based stock compensation expenses primarily related to an increase in share-based stock compensation, and increases in salaries due to annual merit increases for the three and nine months ended September 30, 2026 compared to the three and nine months ended September 30, 2025.

Previous wording

For the three months ended June 30, 2026, compared to the three months ended June 30, 2025, the change in facilities and other indirect costs was relatively flat. For the six months ended June 30, 2026, compared to the six months ended June 30, 2025, the change in facilities and other indirect costs was related to new leases that commenced in the second half of 2025.

Current wording

For the three months ended September 30, 2026, compared to the three months ended September 30, 2025, the change in facilities and other indirect costs was relatively flat. For the nine months ended September 30, 2026, compared to the nine months ended September 30, 2025, the change in facilities and other indirect costs was related to new leases that commenced in the second half of 2025.

Previous wording

We expect that selling, general and administrative expenses will increase 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.

Current wording

We expect that selling, general and administrative expenses may increase 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.

Previous wording

Interest expense, net consists of interest expense from the liability for the sale of future royalties related to the A&R Royalty Purchase Agreement, the 2026 Convertible Notes outstanding, and the 2031 Convertible Notes outstanding, partially offset by interest income earned on investments.

Current wording

Interest expense, net consists of interest expense from the liability for the sale of future royalties related to the A&R Royalty Purchase Agreement, the 2026 Convertible Notes, and the 2031 Convertible Notes outstanding, partially offset by interest income earned on investments.

Previous wording

During the three and six months ended June 30, 2026, there were no material changes to our critical accounting policies as reported in our 2025 Annual Report.

Current wording

During the three and nine months ended September 30, 2026, there were no material changes to our critical accounting policies as reported in our 2025 Annual Report.

Previous wording

Net product revenue. Net product revenue was $238.8 million for the three months ended June 30, 2026, an increase of $120.5 million, or over 100%, from $118.3 million for the three months ended June 30, 2025. The increase in net product revenue was primarily due to an increase in net product sales of $151.3 million for Sephience, which is in the first year of its launch, partially offset by a decrease in net product sales of $11.7 million for Emflaza and $17.3 million for Translarna. The decrease in Emflaza sales is primarily driven by additional generic competition. The decrease in Translarna sales is primarily due to the EC’s adoption of the CHMP’s negative opinion.

Current wording

Net product revenue. Net product revenue was $275.9 million for the three months ended September 30, 2026, an increase of $144.9 million, or over 100%, from $131.0 million for the three months ended September 30, 2025. The increase in net product revenue was primarily due to an increase in net product sales of $162.3 million for Sephience, which is in the first year of its launch, partially offset by decreases in net product sales of $10.1 million for Emflaza and $2.2 million for Translarna. The decrease in Emflaza sales is primarily driven by additional generic competition. The decrease in Translarna sales is primarily due to the EC’s adoption of the CHMP’s negative opinion.

Previous wording

Collaboration and license revenue*.* Collaboration and license revenue was $50.6 million for the three months ended June 30, 2026, an increase of $47.7 million, or over 100%, from $2.9 million for the three months ended June 30, 2025. For the three months ended June 30, 2026, we recognized $50.6 million, primarily related to a development milestone. In April 2026, Novartis notified the Company that it had initiated the first Phase 3 clinical trial for a Licensed Product (as defined in the Novartis Agreement). Pursuant to the Novartis Agreement, this triggered a $50.0 million milestone payment to us. For the three months ended June 30, 2025, we recognized $2.9 million related to license revenue from the Novartis Agreement for performance obligations completed during the period.

Current wording

Collaboration and license revenue*.* Collaboration and license revenue was $0.2 million for the three months ended September 30, 2026, a decrease of $9.0 million, or 98%, from $9.3 million for the three months ended September 30, 2025. For the three months ended September 30, 2026, we recognized $0.2 million in revenues related to work performed for Novartis. For the three months ended September 30, 2025, we recognized $9.3 million related to license revenue from the Novartis Agreement for performance obligations completed during the period.

Previous wording

Royalty revenue. Royalty revenue was $117.9 million for the six months ended June 30, 2026, an increase of $23.9 million, or 25%, from $94.0 million for the six months ended June 30, 2025. The increase in royalty revenue was due to higher Evrysdi sales in the six months ended June 30, 2026 as compared to the six months ended June 30, 2025. In accordance with the SMA License Agreement, we are entitled to recognize royalties on worldwide annual net sales of the product.

Current wording

*Royalty revenue.*Royalty revenue was $81.7 million for the three months ended September 30, 2026, an increase of $10.9 million, or 15%, from $70.8 million for the three months ended September 30, 2025. The increase in royalty revenue was due to higher Evrysdi sales in the three months ended September 30, 2026 as compared to the three months ended September 30, 2025. In accordance with the SMA License Agreement, we are entitled to recognize royalties on worldwide annual net sales of the product.

Previous wording

Cost of product, collaboration and license sales, excluding amortization of acquired intangible assets. Cost of product, collaboration and license sales, excluding amortization of acquired intangible assets was $19.9 million for the three months ended June 30, 2026, an increase of $8.5 million, or 74%, from $11.4 million for the three months ended June 30, 2025. Cost of product, collaboration and license sales, excluding amortization of acquired intangible assets consists primarily of the costs associated with the Novartis agreement, royalty payments associated with Sephience and Upstaza/Kebilidi net product sales, costs associated with Sephience, Translarna, Upstaza/Kebilidi, and Emflaza product sold during the period, as well as the production costs associated with these products. The increase was primarily driven by the increase in net product sales, which impacted the cost for products sold and royalty expense for the period.

Current wording

Cost of product, collaboration and license sales, excluding amortization of acquired intangible assets. Cost of product, collaboration and license sales, excluding amortization of acquired intangible assets was $23.7 million for the three months ended September 30, 2026, an increase of $7.9 million, or 50%, from $15.8 million for the three months ended September 30, 2025. Cost of product, collaboration and license sales, excluding amortization of acquired intangible assets consists primarily of the costs associated with the Novartis Agreement, royalty payments associated with Sephience and Upstaza/Kebilidi net product sales, costs associated with Sephience, Translarna, Upstaza/Kebilidi, and Emflaza product sold during the period, as well as the production costs associated with these products. The increase was primarily driven by the increase in net product sales, which impacted the cost for products sold and royalty expense for the period.

Previous wording

Amortization of acquired intangible assets. Amortization of acquired intangible assets was $11.8 million for the three months ended June 30, 2026, an increase of $7.8 million, or over 100%, from $4.1 million for the three months ended June 30, 2025. The increase to the intangible assets balance was primarily related to Upstaza/Kebildi and Sephience intangible assets recorded as a result of the regulatory approvals and net sales milestones as well as the Censa Rights Satisfaction Agreement, which increased the corresponding amortization for those assets.

Current wording

Amortization of acquired intangible assets. Amortization of acquired intangible assets was $12.6 million for the three months ended September 30, 2026, an increase of $5.1 million, or 67%, from $7.5 million for the three months ended September 30, 2025. The increase to the intangible assets balance was primarily related to Upstaza/Kebilidi and Sephience intangible assets recorded as a result of the regulatory approvals and net sales milestones as well as the Censa Rights Satisfaction Agreement, which increased the corresponding amortization for those assets.