Ipsen And Sutro Biopharma Announce Exclusive Global Licensing Agreement For An ADC Targeting Solid Tumors

• Ipsen secures exclusive global rights for development and commercialization of STRO-003, an antibody-drug conjugate, completing the final stages of pre-clinical development
• STRO-003 targets ROR1, a clinically validated antibody drug conjugate (ADC) target
• STRO-003 has shown robust monotherapy efficacy and potential for a differentiated safety profile in preclinical development in solid tumors and hematological malignancies¹

Ipsen and Sutro Biopharma today announced an exclusive global licensing agreement for STRO-003. STRO-003, an antibody-drug conjugate (ADC) in the final stages of pre-clinical development, targets the ROR1 tumor antigen which is known to be overexpressed in many different cancer types including solid tumors and hematological malignancies.¹ The agreement gives Ipsen exclusive worldwide rights to develop and commercialize STRO-003 and will be the first ADC candidate joining Ipsen’s expanding portfolio.

“The potential for ADCs in oncology is well-documented and we are excited by the addition of STRO-003, Ipsen’s first ADC candidate with best-in-class potential.” said Mary Jane Hinrichs, SVP and Head of Early Development at Ipsen. “STRO-003 is a next-generation ROR1 ADC, leveraging Sutro’s site-specific technology to generate a highly stable conjugate, coupled with exatecan payloads, that have shown significant potential in solid tumors. This is our focus as we prepare to enter Phase I, harnessing Ipsen’s global expertise in oncology development, while also reinforcing our commitment to bringing new medicines to patients with few treatment options.”

“We are excited to partner STRO-003 with Ipsen to help us reach more patients faster while retaining significant downstream participation in a medicine in which we believe,” said Jane Chung, President and Chief Operating Officer at Sutro. “Sutro’s research innovation represented in STRO-003 illustrates our leadership in ADC design. We look forward to collaborating with Ipsen’s impressive oncology development team to bring a differentiated ROR1-targeted ADC to patients.”

ADCs are comprised of three main components: the antibody, payload and linker. The antibody selectively targets an identified tumor antigen, such as ROR1. Payloads are the pharmaceutically active component to treat the cancer, attached to the antibody via a chemical linker. The linker connects the antibody and the payload and reduces the amount of payload that reaches non-tumor tissue.²

Under the terms of the agreement, Ipsen will assume responsibility for Phase I preparation activities, including submission of the Investigational New Drug (IND) application, and all subsequent clinical-development activities and global commercialization activities. Sutro Biopharma is eligible to receive up to $900m in potential upfront, development, regulatory and commercial milestone payments including approximately $90m in near-term payments, including an equity investment, and tiered royalties on global sales, contingent upon successful development and commercialization.

¹ Preclinical development of STRO-003, a ROR1 targeted antibody-drug conjugate. 14th Annual WADS ADC. San Diego 2023. Available here: https://www.sutrobio.com/wp-content/uploads/2023/10/WADC_SD_2023_HKiefel.pdf
² E. Jabbour, S. Paul, H. Kantarjian. The clinical development of antibody-drug conjugates – lessons from leukemia. Nature Reviews Clinical Onoclogy. 2021. 18: 418-433. Available here: https://www.nature.com/articles/s41571-021-00484-2