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Freshfields Advises Sairopa on Its Collaboration, Option and License Agreement With Exelixis to Produce Novel Oncology Therapies

Freshfields advised Sairopa, a clinical-stage company that develops novel treatments for cancer by modulating the patient’s immune system, on its collaboration and option agreement with Exelixis, a commercially successful, oncology-focused biotechnology company that strives to accelerate the discovery, development and commercialization of new medicines for difficult-to-treat cancers.  

Under the terms of the agreement, Exelixis will make an upfront payment to Sairopa of $40 million and an additional $70 million in near-term milestones for an option to obtain an exclusive, worldwide license to develop and commercialize ADU-1805 and other anti-SIRPα antibodies, and for certain expenses to be incurred by Sairopa in conducting prespecified phase 1 clinical studies of ADU-1805 during the option period. Following the completion of the prespecified clinical studies, Exelixis has the right to exercise its option for an option exercise fee of $225 million. If Exelixis exercises the option, Sairopa is eligible to receive additional payments upon achievement of specified clinical, commercial and net sales milestones, as well as tiered royalties on net sales worldwide.

The Freshfields team is led by life sciences transactions Partner Vinita Kailasanath, antitrust Counsel Laura Onken and Special Counsel Meytal McCoy, along with life sciences transactions Associates Sora Park, Mina Miljevic and Tanny Kang.


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This material is for general information only and is not intended to provide legal advice. Prior results do not guarantee a similar outcome.