The Company entered into various license and collaboration agreements under which it is obligated to make contingent payments as described below.

Allist

​

In June 2021, the Company entered into a Global Technology Transfer and License Agreement with Allist (“Allist Agreement”). Pursuant to the Allist Agreement, the Company was granted an exclusive license under certain intellectual property to develop, manufacture and commercialize certain licensed products in the field in the licensed territory. Upon execution of the Allist Agreement, the Company paid Allist a non-refundable cash payment of $40.0 million and issued 1,276,250 shares of its common stock. The upfront payment and the fair value of the common stock issued was recorded to research and development expense in 2021.

​

Upon the achievement of certain clinical, regulatory and commercial milestones using the licensed technology, the Company is obligated to make future milestone payments to Allist of up to $105.0 million in clinical and regulatory milestones and up to $655.0 million in commercial milestones. Furthermore, royalties, ranging from high single digit to low mid-teen percentages will be payable to Allist on net sales of licensed products in licensed territories.

​

In connection with the Allist Agreement, in December 2021, the parties also entered into a Joint Clinical Collaboration Agreement (“Clinical Collaboration”) to define the framework under which the parties will cooperate and share costs related to global clinical studies to be conducted jointly by the Company and Allist. During the three months ended March 31, 2026 and 2025, the Company incurred $0.7 million and $0.5 million, respectively, in cost reimbursements to Allist under the Clinical Collaboration which have been recorded as research and development expense. The Company also received cost reimbursements from Allist of $0.3 and $0.4 million for the three months ended March 31, 2026 and 2025, respectively, which have been recorded as a reduction of research and development expenses. The Company incurred $5.0 million in clinical milestone payments to Allist during the year ended December 31, 2025. Through March 31, 2026, no additional milestones were met or achieved or were probable of achievement.

​

Alphamab

​

In June 2024, the Company entered into a collaboration agreement with Jiangsu Alphamab Biopharmaceuticals Co., Ltd. (“Alphamab”) to discover, develop and commercialize novel antibody drug conjugates (“ADCs”) for the treatment of cancers (“Alphamab Agreement”).

​

Under the Alphamab Agreement, both companies seek to leverage Alphamab’s proprietary linker-payload platform and glycan-conjugation technology to identify novel ADCs for oncology indications. The Alphamab Agreement gives the Company exclusive rights to develop and commercialize ADCs globally, except Greater China, where Alphamab retains the right to develop and commercialize the ADCs.

​

The terms of the Alphamab Agreement include combined upfront and potential milestone payments to Alphamab of up to $201.5 million based on the achievement of certain regulatory and development milestones, and up to $414.0 million based on the achievement of certain commercial milestones. In addition, Alphamab is entitled to receive tiered sales royalties, ranging from low single digit to mid-single digit percentages, from the Company for net sales of each ADC product.

​

The upfront payment was recorded to research and development expense during the three-month period ended June 30, 2024. During the three months ended March 31, 2025, the Company paid $0.1 million in cost reimbursements to Alphamab under the Alphamab Agreement which have been recorded as research and development expense. Finally, during the year ended December 31, 2025, the Company paid $1.2 million upon the approval of a target pair selection which was also included in research and development expense. No such expenses were incurred in the three months ended March 31, 2026. Through March 31, 2026, no further milestones have been met or achieved, or are probable of achievement, since the inception of the agreement.

​

Aarvik

​

In December 2021, the Company entered into a Research Collaboration Agreement, as amended, effective June 30, 2023 (the “Aarvik Collaboration Agreement”), with Aarvik Pharmaceuticals, Inc. (“Aarvik”), under which the Company is required to pay Aarvik up to $3.1 million on statements of work (“SOWs”) and an initiation fee of $0.3 million. After the completion of the SOWs, the Company has an exclusive option to license the Aarvik intellectual property, and the option to acquire certain of Aarvik’s intellectual property, after which it is the Company’s sole responsibility to research, develop, manufacture and commercialize any applicable compound and product in the field and territory. In August 2024, the Company paid $1.0 million to exercise that option, and as a result is now obligated to pay up to $18.0 million per product upon the achievement of certain clinical and regulatory milestone events and up to $80.0 million per product in commercial milestones. Additionally, the Company is obligated to pay Aarvik royalties in the mid-single digits based on net sales of licensed products.

​

On August 9, 2024, the Company entered into an amendment and restatement of the Aarvik Collaboration Agreement, as amended on July 2, 2025 (the “Amended and Restated Aarvik Collaboration Agreement”). Under the Amended and Restated Aarvik Collaboration Agreement, Aarvik granted the Company an exclusive option to obtain exclusive rights to certain of Aarvik’s intellectual property for the research, development, manufacture, use, commercialization, or other exploitation of the ADCs related to (i) the two agreed targets to which the compounds being developed under the collaboration bind, and (ii) the acquisition of exclusive rights to certain intellectual property generated during the collaboration. ARR-002, a novel tetravalent MUC16/NaPi2b targeting ADC, was discovered through the collaboration with Aarvik.  ArriVent recently announced US IND clearance for ARR-002 and its expectation to initiate a Phase 1 trial and dose a first patient in the second half 2026.

​

From inception to date, under the Amended and Restated Aarvik Collaboration Agreement, the Company has paid Aarvik a collaboration initiation fee and research fees as provided in the SOWs in an aggregate amount of $5.4 million.

​

The Company incurred $0.1 million in research and development expenses related to the Aarvik SOWs during the three months ended March 31, 2025. No such expenses were incurred during the three months ended March 31, 2026. No milestones have been met or achieved, or are probable of achievement, since the inception of the Aarvik Collaboration Agreement.

​

Lepu

​

On January 21, 2025, the Company entered into an Exclusive License Agreement (the “Lepu Biopharma Agreement”) with Lepu Biopharma Co., Ltd. (“Lepu”), pursuant to which Lepu granted the Company a right to develop and commercialize ARR-217, an antibody drug conjugate for gastrointestinal cancers outside Greater China.

​

Under the Lepu Biopharma Agreement, Lepu granted to the Company: (i) an exclusive, royalty-bearing, sublicensable license under certain intellectual property owned or controlled by Lepu, to develop, manufacture and commercialize any product containing ARR-217 for all uses in all countries and territories other than Greater China (the “ArriVent Territory”); and (ii) a non-exclusive license under certain intellectual property controlled by Lepu to develop, manufacture and commercialize any product containing ARR-217 for use in oncology in the ArriVent Territory. Under the Lepu Biopharma Agreement, the Company paid Lepu a one-time upfront payment of $40 million and, during the three months ended June 30, 2025, the Company paid $1.0 million to Lepu for the achievement of the first developmental milestone under the Lepu Biopharma Agreement as it became probable of achievement during the second quarter. The upfront payment was included in research and development expenses. Finally, Lepu is eligible to receive payments of up to $0.3 billion in development and regulatory milestones, and up to $0.89 billion in commercial milestones, and tiered royalties in high single-digit to low-teen percentages on net sales in the ArriVent Territory.

​

During the three months ended March 31, 2026, Lepu earned a $6.0 million developmental milestone payment. No milestones have been met or achieved, or are probable of achievement, subsequent to the developmental milestone noted above. During three months ended March 31, 2026, the Company incurred an additional $0.8 million in research and development expenses related to the Lepu Biopharma Agreement. No such expenses were incurred during the three months ended March 31, 2025.

​