Below, we have included our Biogen, GSK, Ono, Otsuka, Recordati and Roche collaborations, which were the only collaborations that had either substantive changes or were new from those included in Part IV, Item 15, Note 4, Collaborative Arrangements and Licensing Agreements, of our audited financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2025.

We have multiple collaborations with Biogen focused on using antisense technology to advance the treatment of neurological disorders, including our 2017 spinal muscular atrophy, or SMA, collaboration and 2018 neurology collaboration.

In 2017, we entered into a collaboration agreement with Biogen to identify new antisense medicines for the treatment of SMA. In 2021, Biogen exercised its option to license salanersen, a drug we discovered under this collaboration.

In the second quarter of 2026, we earned a $45 million milestone payment when Biogen initiated a Phase 3 trial of salanersen for SMA under this collaboration. We recognized this milestone payment as R&D revenue in full in the second quarter of 2026 because we did not have any remaining performance obligations related to the milestone payment. We will achieve the next payment of $55 million if Biogen achieves approval in a major market, which includes the U.S., Japan, the United Kingdom, Germany, France, Italy and Spain. From inception through June 30, 2026, we have received $130 million in payments under this collaboration.

Under our 2018 neurology collaboration, Biogen gained exclusive rights to the use of our antisense technology to develop therapies for certain neurological diseases and the option to license certain medicines resulting from this collaboration. If Biogen exercises its option to license a medicine, it will assume global development, regulatory and commercialization responsibilities and costs for that medicine.

In the second quarter of 2026, we earned a $15 million license fee payment when Biogen exercised its option to license an investigational candidate for the treatment of amyotrophic lateral sclerosis, or ALS, under this collaboration. We recognized this license fee payment as R&D revenue in full in the second quarter of 2026 because we did not have any remaining performance obligations related to this payment after we delivered the license to Biogen. We will achieve the next payment of $7.5 million if Biogen advances a medicine under this collaboration. From inception through June 30, 2026, we have received approximately $1.1 billion in payments under this collaboration, including payments to purchase our stock.

In 2010, we entered into a collaboration with GSK using our antisense drug discovery platform to discover and develop new medicines against targets for serious and rare diseases, including infectious diseases. Under our collaboration, GSK is developing bepirovirsen for the treatment of chronic hepatitis B, or CHB, infection. In 2019, following positive Phase 2 results, GSK licensed our CHB program. GSK is responsible for all global development, regulatory and commercialization activities and costs for the CHB program.

In the second quarter of 2026, we amended our CHB collaboration agreement with GSK, resulting in increased milestone payments that we are eligible to receive under this collaboration and amended royalty terms that exclude net sales in China, Hong Kong and Macau. Under the amended agreement, we are eligible to receive more than $510 million, which is comprised of a $25 million license fee, up to $46.5 million in development milestone payments, up to $320 million in regulatory milestone payments and up to $120 million in sales milestone payments if GSK successfully develops and commercializes bepirovirsen. In addition, we are eligible to receive tiered royalties ranging from 10 to 12 percent on net sales of bepirovirsen worldwide, excluding China, Hong Kong and Macau. The amendments to the agreement did not change existing performance obligations or result in new performance obligations. Therefore, we did not record any adjustments to previously recognized revenue.

In the first quarter of 2026, we earned a $15 million milestone payment when the Japanese Ministry of Health, Labour and Welfare, or MHLW, accepted for review a New Drug Application, or NDA, filing for bepirovirsen. In addition, we earned a $15 million milestone payment when the European Medicines Agency, or EMA, accepted for review a Marketing Authorization Application, or MAA, filing for bepirovirsen. We recognized these milestone payments as R&D revenue in full in the first quarter of 2026 because we did not have any remaining performance obligations related to the milestone payments. We will achieve the next payment of $35 million if bepirovirsen is approved in a major country other than China. From inception through June 30, 2026, we have received more than $135 million in an upfront payment and other payments related to the CHB program.

In March 2025, we entered into an agreement with Ono Pharmaceutical Co., Ltd., or Ono, to develop and commercialize sapablursen, an investigational RNA-targeted medicine for the potential treatment of polycythemia vera, or PV, a rare and potentially life-threatening hematologic disease. We are responsible for completing the Phase 2 IMPRSSION study of sapablursen, including the ongoing extension period. Ono is solely responsible for subsequent development, regulatory filings and commercialization of sapablursen.

In the second quarter of 2026, we earned a $20 million milestone payment when Ono initiated a pivotal clinical trial for sapablursen under this collaboration. We recognized this milestone payment as R&D revenue in full in the second quarter of 2026 because we did not have any remaining performance obligations related to the milestone payment. We will achieve the next payment of $15 million if the FDA accepts a New Drug Application, or NDA, filing for sapablursen in the U.S. From inception through June 30, 2026, we have received more than $305 million in payments from Ono.

We did not have any deferred revenue from our relationship with Ono at June 30, 2026. Our consolidated balance sheet at December 31, 2025 included deferred revenue of $2.9 million from our relationship with Ono.

In 2023, we entered into an agreement with Otsuka Pharmaceutical Co., Ltd., or Otsuka, to commercialize DAWNZERA in Europe. In the second quarter of 2024, we expanded the agreement to include commercialization rights for DAWNZERA in the Asia-Pacific region. We are responsible for the ongoing development of DAWNZERA. We retained the rights to commercialize DAWNZERA in the U.S. and in the rest of the world, assuming regulatory approval. In November 2024, we entered into an agreement with Otsuka to commercialize ulefnersen, an investigational medicine for the treatment of ALS, caused by mutations in the FUS gene, worldwide. We are responsible for the ongoing development of ulefnersen.

In the first quarter of 2026, we achieved a $15 million milestone payment when the European Commission approved DAWNZERA in the EU. We recognized this milestone payment as R&D revenue in full in the first quarter of 2026 because we did not have any remaining performance obligations related to the milestone payment. We will achieve the next payment of $20 million if Otsuka receives reimbursement approval in three of the five major European countries, which include the United Kingdom, France, Germany, Italy and Spain. From inception through June 30, 2026, we have received more than $125 million in payments from Otsuka.

In June 2026, we entered into an agreement with Recordati AG., or Recordati, to commercialize zilganersen for the treatment of Alexander disease, or AxD, in countries outside of the U.S. We are responsible for the ongoing development of zilganersen globally. We retained the rights to commercialize zilganersen in the U.S., assuming regulatory approval. Recordati is responsible for regulatory filings and commercialization outside the U.S., including country-specific support for early access pathways based on local regulations and access dynamics.

Over the term of this collaboration, we are eligible to receive up to $75 million, which is comprised of a $30 million upfront payment, up to $15 million in regulatory milestone payments and up to $30 million in sales milestone payments. In addition, we are eligible to receive tiered royalties of up to the mid-20 percent range on net sales. We are also eligible to receive reimbursements for clinical development costs that we incur outside the U.S. after March 2028. We received the $30 million upfront payment in July 2026. We will achieve the next payment of up to $10 million if zilganersen is approved in a country outside of the U.S.

At inception, we identified two performance obligations under this agreement, comprised of our license of zilganersen to Recordati and R&D services for zilganersen. We determined the transaction price to be the $30 million upfront payment. We allocated the transaction price based on the estimated stand-alone selling price of each performance obligation as follows:

We recognized $21.0 million of R&D revenue for the license of zilganersen in the second quarter of 2026 because we completed the performance obligation when we delivered the license to Recordati. We are recognizing revenue for our R&D services performance obligation relative to our total effort expected to satisfy our performance obligation. We currently estimate we will satisfy our performance obligation in the second quarter of 2031. In addition, we will recognize reimbursements for clinical development costs as R&D revenue in the period that we incur the costs.

We have two collaborations with Hoffmann-La Roche Inc. and F. Hoffmann-La Roche Ltd, collectively Roche: one to develop sefaxersen for the treatment of immunoglobulin A, or IgA, nephropathy, or IgAN, and one to develop RNA-targeted programs for Alzheimer’s disease, or AD, and Huntington’s disease, or HD.

In the first quarter of 2026, we earned a $50 million milestone payment when Roche initiated a Phase 1 trial for an investigational medicine for the treatment of AD. We recognized this milestone payment as R&D revenue in full in the first quarter of 2026 because we did not have any remaining performance obligations related to the milestone payment. We will achieve the next payment of $10 million if Roche initiates a Phase 2 trial for an investigational medicine for the treatment of AD under our collaboration for RNA-targeted programs for AD and HD. From inception through June 30, 2026, we have received more than $405 million in payments from our Roche collaborations.