PD-1 and PD-L1 molecules are a type of immune checkpoint molecule (a general term for a group of molecules that regulate the immune system), and when the PD-1 molecule on lymphocytes binds to the PD-L1 molecule in tumor cells. , Lymphocytes can no longer attack the tumor.Immune checkpoint molecule inhibition therapy is a method of administering an antibody drug that blocks the binding of these two molecules and causing the lymphocytes to attack the tumor again.

　In humans, immune checkpoint molecule inhibition therapy using antibody drugs against immune checkpoint molecules has been developed and used as a therapeutic agent for various malignant tumors.Treatments such as surgery, radiation, and anti-cancer drugs are performed for cancer in dogs, but if it is ineffective or if it is advanced cancer, there is no other effective means, and an immune checkpoint for dogs. Molecular inhibitory antibodies have not yet been developed.

　This time, the research group created an anti-dog PD-1 canine antibody against malignant tumors in dogs by gene recombination technology based on the previously developed monoclonal antibody specific for dog PD-1 molecule.This antibody drug inhibits the binding of PD-1 and PD-L1 in dogs, and further reduces immunogenicity by dogification, enabling long-term administration.When administered to a total of 30 dogs with advanced malignant tumors who visited the veterinary medical center, a response was observed in 4 of 15 (4%) stage 26.7 oral malignant melanomas with lung metastasis. Some effects were also observed in tumors other than.

　The results of this research show that this treatment method is useful as a treatment method for malignant tumors in dogs, and it is expected that the effect will be investigated in clinical trials using a wide range of cases in the future.

Paper information:[Scientific Reports] A pilot clinical study of the therapeutic antibody against canine PD-1 for advanced spontaneous cancers in dogs