On June 25, 2022 Dragon Boat reported that its IND application of the innovative anti-CLDN 18.2/CD47 bi-specific antibody (bsAb) injection (R&D code: BC007) was officially accepted by National Medical Products Administration (NMPA) under the acceptance number CXSL2200267 (Press release, Dragonboat Biopharmaceutical, JUN 25, 2022, View Source [SID1234616258]). This drug is the first domestic clinical filing of the CLDN 18.2/ CD47 bsAb, which is intended for the treatment of late stage solid tumors.
BC007 is a innovative bsAb targeting CLDN 18.2 and CD47 and the early-stage development was completed collaboratively by Sanyou and Dragon Boat. Validation results of the in vivo efficacy showed that BC007 exhibited dose-dependent anti-tumor effects against CLDN18.2 overexpressing CDX mouse models of human gastric cancer, human pancreatic cancer and human colon cancer, and was significantly better than the selected comparator antibody. In the safety studies, hematological toxicity is one of the common challenges of CD47 targeting antibodies. But in the cynomolgus monkey toxicity study, multiple doses of BC007 was administered for 5 weeks without animal death, and the hematological toxicity was mild and well tolerated by the animals.
In March this year, the IND application of anti-CLDN 18.2 antibody injection (BC008) developed by Dragon Boat has been approved by National Medical Products Administration. In the future, Dragon Boat will bring greater clinical benefits to the patients by exploring more treatment options.
Dr. Guojun Lang, CEO of Sanyou, said "We sincerely congratulate Dragon Boat on the NMPA acceptance of IND application with the CLDN 18.2/CD47 bsAb, which is another milestone after the clinical approval of the anti-CLDN 18.2 nanoantibody co-developed by Sanyou and Dragon Boat in March. This project further proves the outstanding competency of Dragon Boat in the field of innovative biopharmaceutical research and development. This project is also another successful case of Sanyou’s Cooperative Project Organization (CPO) business model. We wish the clinical studies will proceed successfully and benefit the patients as soon as possible".
About CLDN 18.2
Tight junction protein claudin-18 isoform 2 (CLDN18.2) is a member of the claudin family, which includes tight junction proteins that establish paracellular barriers to control the molecular passage and motions among cells. Normally, CLDN 18.2 is expressed only on the surface of differentiated epithelial cells of the gastric mucosa. However, after the development of malignant tumors, tight junction proteins are disrupted, exposing the CLDN 18.2 epitope on the surface of tumor cells. Studies have shown high CLDN 18.2 expression in the tumor cells of 50%-80% of gastric cancer patients and 60% of pancreatic cancer patients.
CD47 is a glycosylated transmembrane protein, a key member of the immunosuppressive signaling pathway, which inhibits macrophage phagocytosis and mediates the immune escape mechanism of various malignant tumors, mainly by interacting with the inhibitory receptor signal-regulatory protein alpha (SIRPα), which is widely recognized as a "don’t eat me" signal. Numerous studies have shown that CD47 is overexpressed in different types of tumors, including myeloma, smooth muscle sarcoma, acute lymphoblastic leukemia, and non-Hodgkin’s lymphoma.