- STCube presented preclinical data of ‘hSTC810’, a First-In-Class antibody product targeting ‘BTN1A1’, at the American Association for Cancer Research (AACR)The company’s novel drug targeting ‘BTN1A1’ was successfully presented at the AACR poster session. ‘BTN1A1’ is an immune checkpoint protein that suppresses the proliferation of CD8+ T cells, which normally acts to inhibit the growth of tumor cells. The protein is highly expressed in solid tumors that poorly respond to immunotherapies targeting PD-1/PD-L1. Using a self-developed IHC antibody, STCube showed that ‘BTN1A1’ is highly expressed in tumor cells of the squamous cell carcinoma (56.3%), head and neck (84.5%), bladder cancer (75%), and breast cancer (63.2%). In particular, the protein shows a high expression rate of 56.1% in ovarian cancer in which PD-L1 is known to rarely express. In addition, it was confirmed through OPAL staining that the expressions of ‘BTN1A1’ and PD-L1 are mutually exclusive. This implies that ‘BTN1A1’ is a novel immune checkpoint protein distinct from PD-1/PD-L1. The company plans to initiate global clinical trials upon obtaining IND approval from US food and Drug Administration (FDA) in the second half of this year. Various development options, including co-development with and/or licensing out to multinational pharmaceutical companies, are being explored at the current time. STCube’s presentation in the AACR 2021 can be viewed by downloading the attached file.
STCube, a biotech focused on developing immunotherapies for cancer, announced on December 9 that results from research conducted on its small molecule immunotherapeutic agent ‘SD133’ was published in Gastroenterology, a prestigious scientific journal in the field. ‘SD133’ is a small molecule agent being developed as treatment for pancreatic cancer in collaboration with researchers from Georgetown University. The publication contains promising results for a novel therapeutic agent for pancreatic cancer, which is known to have poor prognosis, and for which very limited treatment options are available. As such, the publication attracted significant interest in the field and was reported in several news articles overseas. ‘CDH11’, the immune modulator target for the small molecule agent, has been known to be associated with various autoimmune disorders, but little had been revealed on its involvement in cancers. The expression of ‘CDH11’ on tumor cells of breast and prostate cancers had been previously reported, but researchers on this publication discovered that in pancreatic cancer, ‘CDH11’ expresses on stromal cells such as cancer-associated fibroblasts, rather than tumor cells, and plays a critical role in the formation and growth of tumor cells. Thus, the publication reveals for the first time that, in the case of pancreatic cancer in particular, treatments targeting tumor cells themselves may show limited efficacy, but treatments targeting immune modulators expressed on stromal cells, which surround tumor cells and defend them from immune attacks, may be critical in achieving better clinical efficacy. Survival periods for animals that either express or do not express ‘CDH11’ were monitored based on genetically modified animal models developed by the company. While the survival period for animals that express ‘CDH11’ was only 17 days due to rapid growth of implanted tumors, animals that do not express ‘CDH11’ showed a significantly extended period of survival (101 days) with much slower growth of implanted tumors. Stemming from this discovery, ‘SD133’, a small molecule inhibitor of ‘CDH11’, was developed, and the compound’s efficacy in treating cancer was demonstrated in pancreatic cancer transplanted mouse models. This finding provides a leeway for the immune-modulating agent ‘SD133’ to be used in the treatment of pancreatic cancer, alone or in combination with other chemotherapeutic agents. According to the company’s spokesman, ‘SD133’ is “a result of several years’ research and development, and the publication in this prestigious scientific journal evidences that the published results on pancreatic cancer are highly regarded in the field.” It was added that “the significance of the published results is also evidenced by the fact the publication was reported in several overseas news articles, and as such, the company plans to keep moving forward with regard to potential co-development and/or licensing out of this technology.”