TOKYO and SAN DIEGO, June 14, 2023 - Astellas Pharma Inc. (TSE: 4503, President and CEO: Naoki Okamura, “Astellas”) and Cullgen Inc. (President and CEO: Ying Luo, Ph.D., “Cullgen”) today announced a research collaboration and exclusive option agreement to discover multiple innovative protein degraders.

Under the terms of the agreement, the two companies aim to develop multiple targeted protein degraders by combining Cullgen's proprietary uSMITE™ targeted protein degradation platform featuring novel E3 ligands with Astellas' drug discovery capabilities. Cullgen and Astellas will collaboratively conduct joint research to identify clinical development candidates. Astellas will then have an exclusive option of exclusively license the rights for clinical development and commercialization of the protein degrader compounds identified during the research activities. Cullgen will have the option during the initial stages of clinical development to participate equally in the costs, profits and losses, and to co-promote partnered products in the U.S. for the lead program, previously identified by Cullgen as a cell cycle protein degrader for the treatment of breast cancer and other solid tumors.

“Targeted Protein Degradation is one of the Primary Focuses of Astellas*1,” said Adam Pearson, Chief Strategy Officer at Astellas. "We hope this collaboration will bring synergies between the two companies' cutting-edge research, and will ultimately lead to the expansion of Astellas’ portfolio and development of new therapeutics for patients with significant unmet medical needs.”

“We are excited to enter into this strategic collaboration with Astellas using our novel E3 ligands which we discovered in-house,” Ying Luo, President and CEO at Cullgen said, “We are looking forward to working with Astellas to advance more targeted protein degraders into clinical development.”

Astellas will provide Cullgen an upfront payment of $35M USD. Cullgen is also entitled to receive an additional $85M USD upon Astellas’ exercise of the license option with respect to the lead program. Total compensation to Cullgen could exceed $1.9 billion if Astellas exercises all of its license options and all milestones for all programs are achieved. Cullgen is also eligible to receive royalty payments from Astellas on any potential commercial sales.


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