LigaChem Biosciences announced on the 9th that it will receive milestone payments based on successful product development under the antibody-drug conjugate (ADC) platform technology transfer agreement signed with Czech Sotio Biotech in 2021. The scale of the milestone was not disclosed due to confidentiality agreements between the two companies.
This milestone is related to the progress in the development of the ADC therapeutic SOT106 for the treatment of LRRC15 (a protein that appears on the surface of cancer cells) tumors in sarcoma (cancer occurring in muscle and bone connective tissue). Sotio plans to submit an Investigational New Drug (IND) application for global clinical trials of SOT106 in the second half of this year.
Through the collaboration that began in 2021, Sotio has been developing solid tumor therapeutics by combining its proprietary antibodies with LigaChemBio's next-generation ADC platform technology, ConjuAll. ConjuAll is a platform for the conjugation of antibodies and toxic drugs in ADCs.
At the time of the technology transfer, LigaChemBio secured the right to receive up to $1.0275 billion (approximately 1.5 trillion won) in milestones and separate royalties based on sales, depending on the achievements at various stages of development and approval. Sotio is responsible for the research, development, manufacturing, and commercialization of the ADC candidates derived from the platform agreement.
Preclinical research results presented at the American Association for Cancer Research (AACR) in 2025 confirmed that SOT106 has the potential to be a best-in-class ADC therapeutic for sarcoma treatment. In mouse models of soft tissue sarcoma and osteosarcoma, SOT106 demonstrated strong anticancer efficacy compared to control ADC therapeutics using the same MMAE payload, and complete responses were observed at clinically appropriate doses (1 mg/kg).
