LigaChem Biosciences said on the 4th that SOTIO Biotech of the Czech Republic, its partner developing an antibody-drug conjugate (ADC) candidate, has received orphan drug designation (ODD) from the U.S. Food and Drug Administration (FDA) for the treatment of osteosarcoma.
ODD is a system that supports the development of new drugs for diseases with few patients or a lack of treatments. If a designated therapy wins approval, it can receive benefits including up to seven years of market exclusivity, certain fee waivers, and FDA development support.
The ADC candidate SOT106, which received ODD this time, is an osteosarcoma treatment candidate that combines SOTIO's LRRC15-targeting antibody with LigaChem Biosciences' next-generation ADC platform technology ConjuALL. ConjuALL is designed to precisely link drugs to specific sites on antibodies, a feature that enhances the stability and therapeutic efficiency of ADCs.
LigaChem Biosciences signed a technology licensing agreement for its ADC platform with SOTIO in Nov. 2021. Through this, SOTIO secured global development and commercialization rights for ConjuALL-based multi-target ADC therapies, and the two companies have continued joint research to date.
LRRC15, the target of SOT106, is known to be scarcely expressed in normal tissues but highly expressed in various sarcoma cancer cells and the tumor microenvironment, including osteosarcoma and soft tissue sarcoma. For this reason, it is regarded as a promising target that can attack cancer cells more selectively.
In preclinical studies, anticancer efficacy and excellent tolerability were confirmed in osteosarcoma and soft tissue sarcoma models. SOTIO plans to begin a clinical trial in the second half of this year with the goal of dosing the first patient.
Radek Spisek, SOTIO chief executive officer (CEO), said, "This orphan drug designation recognizes the high treatment need in osteosarcoma and the development potential of SOT106."
Meanwhile, osteosarcoma is a representative bone cancer that mainly occurs in children, adolescents, and young adults. Surgery, radiation therapy, and chemotherapy are currently used as standard treatments, but outcomes for patients with recurrence or metastasis remain limited. In particular, sarcomas consist of more than 70 different subtypes, making it a field where developing new targeted therapies is considered difficult.