Earlier this week Strategia Therapeutics, an integrated pharmaceutical company, announced that it had initiated a Phase I clinical trial of Fujifilm’s radioimmunotherapeutic agent FF-21101 (90Y) in the United States in patients with advanced solid tumor cancers. The trial is being performed at The University of Texas MD Anderson Cancer Center by Vivek Subbiah, M.D., Assistant Professor in the Department of Investigational Therapeutics and expert in Phase I cancer clinical research of molecularly-targeted radiopharmaceuticals.
FF-21101 (90Y), which inhibits the growth of P-cadherin-expressing solid tumors, is a radioimmunoconjugate consisting of a chimeric monoclonal antibody targeting human cadherin-3 (CDH3), also known as P-cadherin, and labeled, via the macrocyclic chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), with the beta-emitting radioisotope yttrium Y-90, with potential antineoplastic activities.
Mechanism of action
Following administration, the antibody moiety of Yttrium Y-90 anti-CDH3 monoclonal antibody FF-21101 binds to CDH3 expressed on tumor cells, thereby specifically delivering cytotoxic beta radiation to CDH3-expressing tumor cells. CDH3 is a tumor-associated antigen (TAA) and member of the cadherin family. The protein is overexpressed in a number of common types of cancer, including lung, pancreatic and colon cancers, and plays a role in cell adhesion, motility, invasion, and proliferation.
FF-21101(90Y) is expected to be more effective than an antibody therapy targeted to P-cadherin alone. In preclinical evaluation of FF-21101, significant tumor growth inhibition was observed in various tumor models. The trial drug exhibited high anti-tumor efficacy and low toxicity in animal experiments. 
Safety and preliminary proof of activity
MD Anderson is one of the world’s top general cancer centers with over 10,000 patients enrolled in therapeutic clinical trials each year and approximately 20,000 employees. Strategia is able to utilize one of the world’s top-level clinical testing facilities at MD Anderson under a Strategic Alliance Agreement to carry out the Phase I clinical trial to gain safety and preliminary proof of activity in cancer patients at an early stage.
“Radioimmunotherapeutic antibody drug conjugates are a relatively new approach for clinical investigational research, with the success of drugs targeting CD20, like Zevalin®, Bexxar® and the newer investigational agents that target solid tumor cell surface markers conjugated to a radionuclide, explained Linda Paradiso, DVM, MBA, Chief Operating Officer for Strategia. “Coupling a radionuclide with targeted drug therapy is expected to be more effective than either modality alone and an important next step for newer targeted antibody-radionuclide conjugate therapeutics for the treatment of advanced solid tumors,” she continued.