Note 3 – License Agreements

Dana-Farber Cancer Institute

In March 2015, the Company entered into an exclusive license agreement with Dana-Farber Cancer Institute (“Dana Farber”) to develop a portfolio of fully human immuno-oncology targeted antibodies. Dana-Farber is eligible to receive payments of up to an aggregate of approximately $21.5 million for each licensed product upon the Company’s successful achievement of certain clinical development, regulatory and first commercial sale milestones. In addition, Dana-Farber is eligible to receive up to an aggregate of $60.0 million upon the Company’s successful achievement of certain sales milestones based on aggregate net sales, in addition to royalty payments based

on a tiered low to mid-single digit percentage of net sales. Dana-Farber also receives an annual license maintenance fee of $50,000, which is creditable against future milestone payments or royalties. The portfolio of antibodies licensed from Dana-Farber include antibodies targeting PD-L1, GITR and CAIX.

In connection with the license agreement with Dana-Farber, the Company entered into a collaboration agreement with TGTX, which was amended and restated in June 2019, to develop and commercialize the anti-PD-L1 and anti-GITR antibody research programs in the field of hematological malignancies, while the Company retains the right to develop and commercialize these antibodies in solid tumors. Michael Weiss, Chairman of the Board of Directors of Checkpoint and Fortress’ Executive Vice Chairman, Strategic Development, is also the Executive Chairman, President and Chief Executive Officer and a stockholder of TGTX. The Company is eligible to receive substantive potential milestone payments for the anti-PD-L1 program of up to an aggregate of approximately $27.6 million upon TGTX’s successful achievement of certain clinical development, regulatory and first commercial sale milestones. This is comprised of up to approximately $8.4 million upon TGTX’s successful completion of clinical development milestones, and up to approximately $19.2 million upon regulatory filings and first commercial sales in specified territories. The Company is also eligible to receive substantive potential milestone payments for the anti-GITR antibody program of up to an aggregate of approximately $21.5 million upon TGTX’s successful achievement of certain clinical development, regulatory and first commercial sale milestones. This is comprised of up to approximately $7.0 million upon TGTX’s successful completion of clinical development milestones, and up to approximately $14.5 million upon first commercial sales in specified territories. In addition, the Company is eligible to receive up to an aggregate of $60.0 million upon TGTX’s successful achievement of certain sales milestones based on aggregate net sales for both programs, in addition to royalty payments based on a tiered low double-digit percentage of net sales. The Company also receives an annual license maintenance fee, which is creditable against future milestone payments or royalties. TGTX also pays the Company for its out-of-pocket costs of material used by TGTX for their development activities. For the three months ended March 31, 2023 and 2022, the Company recognized approximately $29,000 and $31,000, respectively, in revenue related to the collaboration agreement in the Condensed Statements of Operations.

Adimab, LLC

In October 2015, Fortress entered into a collaboration agreement with Adimab, LLC (“Adimab”) to discover and optimize antibodies using their proprietary core technology platform. Under this agreement, Adimab optimized cosibelimab, the Company’s anti-PD-L1 antibody which it originally licensed from Dana-Farber. In January 2019, Fortress transferred the rights to the optimized antibody to the Company, and Checkpoint entered into a collaboration agreement directly with Adimab on the same day. Under the terms of the agreement, Adimab is eligible to receive payments from the Company of up to an aggregate of approximately $2.5 million upon various filings for regulatory approvals to commercialize the product. In addition, Adimab is eligible to receive royalty payments based on a tiered low single digit percentage of net sales.

In February 2023 the Company expensed a non-refundable milestone payment of $2.2 million to research and development expenses upon the United States Food and Drug Administration’s filing acceptance of the Company’s Biologics License Application (“BLA”) for cosibelimab in metastatic or locally advanced cutaneous squamous cell carcinoma.

NeuPharma, Inc.

In March 2015, Fortress entered into an exclusive license agreement with NeuPharma, Inc. (“NeuPharma”) to develop and commercialize novel irreversible, 3rd generation EGFR inhibitors, including olafertinib, on a worldwide basis other than certain Asian countries. On the same date, Fortress assigned all of its right and interest in the EGFR inhibitors to the Company. NeuPharma is eligible to receive payments of up to an aggregate of approximately $39.0 million upon the Company’s successful achievement of certain clinical development and regulatory milestones in up to three indications, of which $22.5 million are due upon various regulatory approvals to commercialize the products. In addition, NeuPharma is eligible to receive payments of up to an aggregate of $40.0 million upon the Company’s successful achievement of certain sales milestones based on aggregate net sales, in addition to royalty payments based on a tiered mid to high-single digit percentage of net sales.

Jubilant Biosys Limited

In May 2016, the Company entered into a license agreement with Jubilant Biosys Limited (“Jubilant”), whereby the Company obtained an exclusive, worldwide license to Jubilant’s family of patents covering compounds that inhibit BET proteins such as BRD4, including

CK-103. Jubilant is eligible to receive payments up to an aggregate of approximately $88.4 million upon the Company’s successful achievement of certain clinical development and regulatory milestones, of which $59.5 million are due upon various regulatory approvals to commercialize the products. In addition, Jubilant is eligible to receive payments up to an aggregate of $89.3 million upon the Company’s successful achievement of certain sales milestones based on aggregate net sales, in addition to royalty payments based on a tiered low to mid-single digit percentage of net sales.

In connection with the license agreement with Jubilant, the Company entered into a sublicense agreement with TGTX, a related party, to develop and commercialize the compounds licensed in the field of hematological malignancies, while the Company retains the right to develop and commercialize these compounds in the field of solid tumors. The Company is eligible to receive substantive potential milestone payments up to an aggregate of approximately $87.4 million upon TGTX’s successful achievement of clinical development and regulatory milestones. This is comprised of up to approximately $25.5 million upon TGTX’s successful completion of three clinical development milestones for two licensed products, and up to approximately $61.9 million upon the achievement of five regulatory approvals and first commercial sales in specified territories for two licensed products. In addition, the Company is eligible to receive potential milestone payments up to an aggregate of $89.3 million upon TGTX’s successful achievement of certain sales milestones based on aggregate net sales by TGTX, for two licensed products, in addition to royalty payments based on a mid-single digit percentage of net sales by TGTX. TGTX also pays the Company 50% of Investigational New Drug enabling costs and patent expenses. For the three months ended March 31, 2023 and 2022, the Company recognized approximately $6,000 and $21,000, respectively, in revenue related to the sublicense agreement in the Condensed Statements of Operations.

The collaborations with TGTX each contain single material performance obligations under Topic 606, which is the granting of a license that is functional intellectual property. The Company’s performance obligation was satisfied at the point in time when TGTX had the ability to use and benefit from the right to use the intellectual property. The performance obligations of the original agreements were satisfied prior to the adoption of Topic 606. The performance obligation of the amendment to the collaboration agreement was satisfied in June 2019.

The milestone payments are based on successful achievement of clinical development, regulatory, and sales milestones. Because these payments are contingent on the occurrence of a future event, they represent variable consideration and are constrained and included in the transaction price only when it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur. The sales-based royalty payments are recognized as revenue when the subsequent sales occur. The Company also receives variable consideration for certain research and development, out-of-pocket material costs, and patent maintenance related activities. These amounts are dependent upon the Company’s actual expenditures under the collaborations and are constrained and included in the transaction price only when it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur. As this revenue relates to an already satisfied performance obligation, it is recognized approximately when the amounts become due. For the three months ended March 31, 2023, the Company did not receive any milestone or royalty payments.