License and Collaboration Agreements	9 Months Ended
Sep. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
License and Collaboration Agreements	10. License and Collaboration Agreements Sobi License and Collaboration Agreement In October 2020, the Company and its subsidiaries, Apellis International GmbH (f/k/a Apellis Switzerland GmbH) and APL DEL Holdings, LLC, entered into a Collaboration and License Agreement (the “Sobi collaboration agreement”) with Sobi, concerning the development and commercialization of pegcetacoplan and specified other structurally and functionally similar compstatin analogues or derivatives for use systemically or for local non-ophthalmological administration (collectively referred to as the “Licensed Products”). Under the Sobi collaboration agreement, the Company granted Sobi an exclusive (subject to certain retained rights of the Company), sublicensable license of certain patent rights and know-how to develop and commercialize Licensed Products in all countries outside of the United States. The Company retains the right to commercialize Licensed Products in the United States, and, subject to specified limitations, to develop Licensed Products worldwide for commercialization in the United States. Under the Sobi collaboration agreement, the Company and Sobi agreed to collaborate to develop Licensed Products for certain indications, including PNH, C3G, IC-MPGN and HSCT-TMA (collectively the “Initial Indications”), and any other indications subsequently agreed upon by the parties, for commercialization by or on behalf of the Company in the United States and by or on behalf of Sobi outside of the United States. If the parties do not agree to jointly pursue any development activities for the Licensed Products (whether for an Initial Indication or otherwise), the party proposing to pursue such activities may conduct such activities at its sole expense (with the non-proposing party having the right to obtain rights to the data generated by such development activities by paying a specified percentage of that expense), subject to agreed-upon exceptions that limit each party’s unilateral development rights. In July 2025, the Company and Sobi decided to discontinue development of systemic pegcetacoplan for Transplant-associated Thrombotic Microangiopathy (TA-TMA) (inclusive of HSCT-TMA), following completion of the Phase 2 study and a strategic assessment of the TA-TMA market landscape. The initial development plan sets forth the initial development activities to be conducted by each of the Company and Sobi, with the Company bearing all costs incurred in conducting the activities set forth in such initial development plan, as well as certain specified additional costs that are not included in the initial development plan that may be incurred by the parties in developing Licensed Products for PNH in the European Union and the United Kingdom. The Company and Sobi formed several governance committees to oversee the development and manufacture, and to review and discuss the commercialization, of Licensed Products. The Company shall supply Licensed Products to Sobi for development and for commercialization outside of the United States in accordance with a supply agreement between the parties. The Sobi collaboration agreement grants Sobi the right to perform or have performed drug product manufacturing of Licensed Products for development and for commercialization outside the United States and to manufacture or have manufactured drug substance under certain circumstances. For the three and nine months ended September 30, 2025 the Company recognized revenues of $5.2 million and $17.2 million, respectively, for the supply of Licensed Products to Sobi, which is included in Licensing and other revenue on the condensed consolidated statements of operations and comprehensive income/(loss). For the three and nine months ended September 30, 2024 the Company recognized revenues of $15.3 million and $36.2 million, respectively, for the supply of Licensed Products to Sobi, which is included in Licensing and other revenue on the condensed consolidated statements of operations and comprehensive income/(loss). Sobi paid the Company an upfront payment of $250.0 million in November 2020 and has agreed to pay up to an aggregate of $915.0 million upon the achievement of specified one-time regulatory and commercial milestone events, of which the Company received $50.0 million in April 2022 for the achievement of a regulatory development milestone in Europe. Sobi also agreed to reimburse the Company for up to $80.0 million in development costs, of which the Company received $65.0 million and waived payment of $15.0 million. The Company will also be entitled to receive tiered, double-digit royalties (ranging from high teens to high twenties) on sales of Licensed Products outside of the United States, subject to customary deductions and third-party payment obligations, until the latest to occur of: (i) expiration of the last-to-expire of specified licensed patent rights; (ii) expiration of regulatory exclusivity; and (iii) ten (10) years after the first commercial sale of the applicable Licensed Product, in each case on a Licensed Product-by-Licensed Product and country-by-country basis. Under the Sobi collaboration agreement, the Company remains responsible for its license fee obligations (including royalty obligations) to the Trustees of the University of Pennsylvania (“Penn”), as a licensor of the Company. On July 1, 2025 (the “Closing Date”), Apellis Pharmaceuticals, Inc. and its subsidiaries Apellis International GmbH and APL DEL Holdings, LLC (collectively, the “Company”) entered into a Royalty Buy-Down Agreement (the “Royalty Agreement”) with Sobi. Under the Royalty Agreement, Sobi paid the Company an upfront payment of $275.0 million and agreed to pay up to an aggregate of $25.0 million upon the European Medicines Agency ("EMA") approval of Aspaveli for C3G and IC-MPGN (collectively, the "purchase price"), and the Company agreed to reduce Sobi’s royalty payment obligations under the Sobi collaboration agreement by 90%, effective July 1, 2025. The royalty reduction is subject to defined caps tied to Aspaveli’s performance, including an initial cap of 1.45x of the purchase price. The royalty reduction subject to the cap is calculated as an amount equal to (A) the royalty payments that would have been payable by Sobi under the Sobi collaboration agreement with respect to aggregate net sales of Aspaveli in the Sobi Territory during the period beginning on July 1, 2025 and ending on the hard cap achievement date if the 90% reduction not been applied, minus (B) the royalty payments that are payable to the Company with the 90% reduction in effect. At any time on or after October 1, 2030, the Company may elect to pay Sobi a one-time payment amount, which shall be counted in determining if a cap is met. If a cap is met, Sobi’s royalty payment obligations under the Sobi collaboration agreement will revert to 100%. The Company has evaluated the terms of the Royalty Agreement and concluded, in accordance with ASC 606 Revenue from Contracts with Customers, the Royalty Agreement is a modification to, and should be accounted for as if it were part of, the existing Sobi collaboration agreement. Therefore, the effect of the modification on the transaction price, being the addition of the $275.0 million upfront payment, was recognized as an adjustment to revenue on the date of the modification. This amount is reflected in licensing and other revenue on the condensed consolidated statement of operations and comprehensive income/(loss) for the three and nine months ended September 30, 2025. The royalty revenues from the sales of Aspaveli will continue to be recorded as licensing and other revenue on the condensed consolidated statement of operations and comprehensive income/(loss) as the sales are made by Sobi outside of the United States. Under the Sobi collaboration agreement, for the three and nine months ended September 30, 2025, the Company recognized $0.6 million and $12.6 million, respectively, of royalty revenue from sales of Aspaveli, which was sold by Sobi outside of the United States. For the three and nine months ended September 30, 2024, the Company recognized $5.0 million and $13.9 million, respectively, of royalty revenue from sales of Aspaveli, which was sold by Sobi outside of the United States. The Company did not recognize any contra-research and development expense for the three and nine months ended September 30, 2025 and 2024. The Company doesn't expect to recognize the additional contra-research and development expense under this agreement. University of Pennsylvania License Agreements Patent License Agreement with Penn (Non-ophthalmic Fields of Use) The Company is party to a license agreement with Penn for an exclusive, worldwide license to specified patent rights for the development and commercialization of products in fields of use, as defined therein. The Company is required to make milestone payments aggregating up to $1.7 million, based upon the achievement of development and regulatory approval milestones, and up to $2.5 million, based upon the achievement of annual sales milestones with respect to each of the first two licensed products. The license agreement also requires the Company to pay low single digit royalties based on net sales of each licensed product, subject to minimum quarterly royalty thresholds. In addition, the Company is obligated to pay a specified portion of income it receives from sublicensees. In January 2021, the Company paid $25.0 million for a sublicense fee owed to Penn related to the Sobi collaboration agreement and another licensing transaction. In August 2021, the Company paid $1.0 million to Penn upon the achievement of a development milestone, net of a credit for the annual license maintenance payment. In June 2022, the Company paid an additional $5.0 million to Penn for a sublicense fee related to the Sobi collaboration agreement. In January 2023, the Company paid $1.0 million to Penn upon the achievement of a sales milestone for EMPAVELI in 2022. In January 2024, the Company paid $0.5 million for a sublicense fee owed to Penn related to Sobi obtaining regulatory approval in Japan. Additionally, in January 2024, the Company paid $1.5 million as a result of the achievement of a sales milestone for EMPAVELI and Aspaveli. For the three and nine months ended September 30, 2025, the Company incurred royalty expense of $2.0 million and $5.3 million, respectively, on sales of EMPAVELI and Aspaveli which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss). For the three and nine months ended September 30, 2024, the Company incurred royalty expense of $1.8 million and $5.0 million, respectively, on sales of EMPAVELI and Aspaveli which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss). Amended and Restated Patent License Agreement with Penn (Ophthalmic Field of Use) The Company is also party to a license agreement with Penn for an exclusive, worldwide license to specified patent rights. The Company is required to make milestone payments aggregating up to $3.2 million based upon the achievement of specified development and regulatory milestones and up to $5.0 million based upon the achievement of specified annual sales milestones with respect to each licensed product, and to pay low single-digit royalties based on net sales of each licensed product and with minimum quarterly royalty thresholds. In addition, the Company is obligated to pay a specified portion of income it receives from sublicensees. In April 2023, the Company paid $2.3 million for the achievement of a regulatory milestone as a result of the FDA approval of SYFOVRE in February 2023. In 2023, the Company incurred $5.0 million as a result of the achievement of sales milestones for SYFOVRE of which the Company paid $2.0 million in October 2023 and the remaining $3.0 million in January 2024. For the three and nine months ended September 30, 2025, the Company incurred royalty expense of $4.9 million and $14.1 million, respectively, on sales of SYFOVRE, which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss). For the three and nine months ended September 30, 2024, the Company incurred royalty expense of $4.9 million and $14.4 million, respectively, on sales of SYFOVRE, which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss). Beam Research Collaboration In June 2021, the Company entered into an exclusive five-year research collaboration (the “Beam collaboration agreement”) with Beam Therapeutics, Inc. (“Beam”) focused on the use of Beam’s proprietary base editing technology to discover new treatments for complement-driven diseases. The Company and Beam agreed to collaborate on up to six research programs focused on C3 and other complement targets in the eye, liver and brain. Under the terms of the Beam collaboration agreement, the Company is responsible for selecting specific genes within the complement system in various organs including the eye, liver and brain (the “Target List”) and providing analytical support while Beam will apply its base editing technology and conduct preclinical research on up to six base editing programs for the Target List. During the first five years of the Beam collaboration agreement, Beam is prohibited from developing on its own or with a third party any base editing therapies associated with the items on the Target List but does not prevent Beam from licensing its intellectual property to a third-party for another purpose outside of the Target List. The Company will have exclusive rights to license each of the six programs and will assume responsibility for subsequent development and commercialization. Beam may elect to enter a 50-50 co-development and U.S. co-commercialization agreement with the Company with respect to any one program licensed under the Beam collaboration agreement and upon such election any license agreement in place at that time, would be terminated. As part of the Beam collaboration agreement, the Company agreed to pay a $50.0 million up-front, non-refundable payment to Beam, which the Company paid in July 2021. The Company paid an additional $25.0 million on the first anniversary of the Beam collaboration agreement in June 2022. The Company and Beam are each responsible for their own costs during the research collaboration. If and after the opt-in license rights are exercised for each of the six programs, Beam will be eligible to receive development, regulatory and sales milestones from the Company, as well as royalty payments on sales. The Beam collaboration agreement has an initial term of five years and may be extended up to two years on a per year program-by-program basis. Further, in August 2025, the Company opted in and entered into a license agreement with Beam to collaborate on the neonatal Fc receptor ("FcRn") in the liver, which triggered an upfront milestone payment of $3.8 million, paid in September 2025. Under this agreement, the Company may pay Beam up to $168.8 million in regulatory and development milestones, up to $215.0 million in sales-based milestones, and may owe low single-digit royalties on annual net sales within the licensed territory.

License and Collaboration Agreements

9 Months Ended

Sep. 30, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

10. License and Collaboration Agreements

Sobi License and Collaboration Agreement

In October 2020, the Company and its subsidiaries, Apellis International GmbH (f/k/a Apellis Switzerland GmbH) and APL DEL Holdings, LLC, entered into a Collaboration and License Agreement (the “Sobi collaboration agreement”) with Sobi, concerning the development and commercialization of pegcetacoplan and specified other structurally and functionally similar compstatin analogues or derivatives for use systemically or for local non-ophthalmological administration (collectively referred to as the “Licensed Products”).

Under the Sobi collaboration agreement, the Company granted Sobi an exclusive (subject to certain retained rights of the Company), sublicensable license of certain patent rights and know-how to develop and commercialize Licensed Products in all countries outside of the United States.

The Company retains the right to commercialize Licensed Products in the United States, and, subject to specified limitations, to develop Licensed Products worldwide for commercialization in the United States.

Under the Sobi collaboration agreement, the Company and Sobi agreed to collaborate to develop Licensed Products for certain indications, including PNH, C3G, IC-MPGN and HSCT-TMA (collectively the “Initial Indications”), and any other indications subsequently agreed upon by the parties, for commercialization by or on behalf of the Company in the United States and by or on behalf of Sobi outside of the United States. If the parties do not agree to jointly pursue any development activities for the Licensed Products (whether for an Initial Indication or otherwise), the party proposing to pursue such activities may conduct such activities at its sole expense (with the non-proposing party having the right to obtain rights to the data generated by such development activities by paying a specified percentage of that expense), subject to agreed-upon exceptions that limit each party’s unilateral development rights. In July 2025, the Company and Sobi decided to discontinue development of systemic pegcetacoplan for Transplant-associated Thrombotic Microangiopathy (TA-TMA) (inclusive of HSCT-TMA), following completion of the Phase 2 study and a strategic assessment of the TA-TMA market landscape.

The initial development plan sets forth the initial development activities to be conducted by each of the Company and Sobi, with the Company bearing all costs incurred in conducting the activities set forth in such initial development plan, as well as certain specified additional costs that are not included in the initial development plan that may be incurred by the parties in developing Licensed Products for PNH in the European Union and the United Kingdom. The Company and Sobi formed several governance committees to oversee the development and manufacture, and to review and discuss the commercialization, of Licensed Products.

The Company shall supply Licensed Products to Sobi for development and for commercialization outside of the United States in accordance with a supply agreement between the parties. The Sobi collaboration agreement grants Sobi the right to perform or have performed drug product manufacturing of Licensed Products for development and for commercialization outside the United States and to manufacture or have manufactured drug substance under certain circumstances. For the three and nine months ended September 30, 2025 the Company recognized revenues of $5.2 million and $17.2 million, respectively, for the supply of Licensed Products to Sobi, which is included in Licensing and other revenue on the condensed consolidated statements of operations and comprehensive income/(loss). For the three and nine months ended September 30, 2024 the Company recognized revenues of $15.3 million and $36.2 million, respectively, for the supply of Licensed Products to Sobi, which is included in Licensing and other revenue on the condensed consolidated statements of operations and comprehensive income/(loss).

Sobi paid the Company an upfront payment of $250.0 million in November 2020 and has agreed to pay up to an aggregate of $915.0 million upon the achievement of specified one-time regulatory and commercial milestone events, of which the Company received $50.0 million in April 2022 for the achievement of a regulatory development milestone in Europe. Sobi also agreed to reimburse the Company for up to $80.0 million in development costs, of which the Company received $65.0 million and waived payment of $15.0 million. The Company will also be entitled to receive tiered, double-digit royalties (ranging from high teens to high twenties) on sales

of Licensed Products outside of the United States, subject to customary deductions and third-party payment obligations, until the latest to occur of: (i) expiration of the last-to-expire of specified licensed patent rights; (ii) expiration of regulatory exclusivity; and (iii) ten (10) years after the first commercial sale of the applicable Licensed Product, in each case on a Licensed Product-by-Licensed Product and country-by-country basis. Under the Sobi collaboration agreement, the Company remains responsible for its license fee obligations (including royalty obligations) to the Trustees of the University of Pennsylvania (“Penn”), as a licensor of the Company.

On July 1, 2025 (the “Closing Date”), Apellis Pharmaceuticals, Inc. and its subsidiaries Apellis International GmbH and APL DEL Holdings, LLC (collectively, the “Company”) entered into a Royalty Buy-Down Agreement (the “Royalty Agreement”) with Sobi.

Under the Royalty Agreement, Sobi paid the Company an upfront payment of $275.0 million and agreed to pay up to an aggregate of $25.0 million upon the European Medicines Agency ("EMA") approval of Aspaveli for C3G and IC-MPGN (collectively, the "purchase price"), and the Company agreed to reduce Sobi’s royalty payment obligations under the Sobi collaboration agreement by 90%, effective July 1, 2025. The royalty reduction is subject to defined caps tied to Aspaveli’s performance, including an initial cap of 1.45x of the purchase price.

The royalty reduction subject to the cap is calculated as an amount equal to (A) the royalty payments that would have been payable by Sobi under the Sobi collaboration agreement with respect to aggregate net sales of Aspaveli in the Sobi Territory during the period beginning on July 1, 2025 and ending on the hard cap achievement date if the 90% reduction not been applied, minus (B) the royalty payments that are payable to the Company with the 90% reduction in effect. At any time on or after October 1, 2030, the Company may elect to pay Sobi a one-time payment amount, which shall be counted in determining if a cap is met. If a cap is met, Sobi’s royalty payment obligations under the Sobi collaboration agreement will revert to 100%.

The Company has evaluated the terms of the Royalty Agreement and concluded, in accordance with ASC 606 Revenue from Contracts with Customers, the Royalty Agreement is a modification to, and should be accounted for as if it were part of, the existing Sobi collaboration agreement. Therefore, the effect of the modification on the transaction price, being the addition of the $275.0 million upfront payment, was recognized as an adjustment to revenue on the date of the modification. This amount is reflected in licensing and other revenue on the condensed consolidated statement of operations and comprehensive income/(loss) for the three and nine months ended September 30, 2025. The royalty revenues from the sales of Aspaveli will continue to be recorded as licensing and other revenue on the condensed consolidated statement of operations and comprehensive income/(loss) as the sales are made by Sobi outside of the United States.

Under the Sobi collaboration agreement, for the three and nine months ended September 30, 2025, the Company recognized $0.6 million and $12.6 million, respectively, of royalty revenue from sales of Aspaveli, which was sold by Sobi outside of the United States. For the three and nine months ended September 30, 2024, the Company recognized $5.0 million and $13.9 million, respectively, of royalty revenue from sales of Aspaveli, which was sold by Sobi outside of the United States.

The Company did not recognize any contra-research and development expense for the three and nine months ended September 30, 2025 and 2024. The Company doesn't expect to recognize the additional contra-research and development expense under this agreement.

University of Pennsylvania License Agreements

Patent License Agreement with Penn (Non-ophthalmic Fields of Use)

The Company is party to a license agreement with Penn for an exclusive, worldwide license to specified patent rights for the development and commercialization of products in fields of use, as defined therein. The Company is required to make milestone payments aggregating up to $1.7 million, based upon the achievement of development and regulatory approval milestones, and up to $2.5 million, based upon the achievement of annual sales milestones with respect to each of the first two licensed products. The license agreement also requires the Company to pay low single digit royalties based on net sales of each licensed product, subject to minimum quarterly royalty thresholds. In addition, the Company is obligated to pay a specified portion of income it receives from sublicensees.

In January 2021, the Company paid $25.0 million for a sublicense fee owed to Penn related to the Sobi collaboration agreement and another licensing transaction. In August 2021, the Company paid $1.0 million to Penn upon the achievement of a development milestone, net of a credit for the annual license maintenance payment. In June 2022, the Company paid an additional $5.0 million to Penn for a sublicense fee related to the Sobi collaboration agreement. In January 2023, the Company paid $1.0 million to Penn upon the achievement of a sales milestone for EMPAVELI in 2022. In January 2024, the Company paid $0.5 million for a sublicense fee owed to Penn related to Sobi obtaining regulatory approval in Japan. Additionally, in January 2024, the Company paid $1.5 million as a result of the achievement of a sales milestone for EMPAVELI and Aspaveli.

For the three and nine months ended September 30, 2025, the Company incurred royalty expense of $2.0 million and $5.3 million,

respectively, on sales of EMPAVELI and Aspaveli which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss).

For the three and nine months ended September 30, 2024, the Company incurred royalty expense of $1.8 million and $5.0 million, respectively, on sales of EMPAVELI and Aspaveli which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss).

Amended and Restated Patent License Agreement with Penn (Ophthalmic Field of Use)

The Company is also party to a license agreement with Penn for an exclusive, worldwide license to specified patent rights. The Company is required to make milestone payments aggregating up to $3.2 million based upon the achievement of specified development and regulatory milestones and up to $5.0 million based upon the achievement of specified annual sales milestones with respect to each licensed product, and to pay low single-digit royalties based on net sales of each licensed product and with minimum quarterly royalty thresholds. In addition, the Company is obligated to pay a specified portion of income it receives from sublicensees.

In April 2023, the Company paid $2.3 million for the achievement of a regulatory milestone as a result of the FDA approval of SYFOVRE in February 2023. In 2023, the Company incurred $5.0 million as a result of the achievement of sales milestones for SYFOVRE of which the Company paid $2.0 million in October 2023 and the remaining $3.0 million in January 2024.

For the three and nine months ended September 30, 2025, the Company incurred royalty expense of $4.9 million and $14.1 million, respectively, on sales of SYFOVRE, which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss).

For the three and nine months ended September 30, 2024, the Company incurred royalty expense of $4.9 million and $14.4 million, respectively, on sales of SYFOVRE, which is included in cost of sales on the condensed consolidated statements of operations and comprehensive income/(loss).

Beam Research Collaboration

In June 2021, the Company entered into an exclusive five-year research collaboration (the “Beam collaboration agreement”) with Beam Therapeutics, Inc. (“Beam”) focused on the use of Beam’s proprietary base editing technology to discover new treatments for complement-driven diseases. The Company and Beam agreed to collaborate on up to six research programs focused on C3 and other complement targets in the eye, liver and brain. Under the terms of the Beam collaboration agreement, the Company is responsible for selecting specific genes within the complement system in various organs including the eye, liver and brain (the “Target List”) and providing analytical support while Beam will apply its base editing technology and conduct preclinical research on up to six base editing programs for the Target List. During the first five years of the Beam collaboration agreement, Beam is prohibited from developing on its own or with a third party any base editing therapies associated with the items on the Target List but does not prevent Beam from licensing its intellectual property to a third-party for another purpose outside of the Target List. The Company will have exclusive rights to license each of the six programs and will assume responsibility for subsequent development and commercialization. Beam may elect to enter a 50-50 co-development and U.S. co-commercialization agreement with the Company with respect to any one program licensed under the Beam collaboration agreement and upon such election any license agreement in place at that time, would be terminated.

As part of the Beam collaboration agreement, the Company agreed to pay a $50.0 million up-front, non-refundable payment to Beam, which the Company paid in July 2021. The Company paid an additional $25.0 million on the first anniversary of the Beam collaboration agreement in June 2022. The Company and Beam are each responsible for their own costs during the research collaboration. If and after the opt-in license rights are exercised for each of the six programs, Beam will be eligible to receive development, regulatory and sales milestones from the Company, as well as royalty payments on sales. The Beam collaboration agreement has an initial term of five years and may be extended up to two years on a per year program-by-program basis.

Further, in August 2025, the Company opted in and entered into a license agreement with Beam to collaborate on the neonatal Fc receptor ("FcRn") in the liver, which triggered an upfront milestone payment of $3.8 million, paid in September 2025. Under this agreement, the Company may pay Beam up to $168.8 million in regulatory and development milestones, up to $215.0 million in sales-based milestones, and may owe low single-digit royalties on annual net sales within the licensed territory.