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.”

STCube, Inc. (“STCube”), a biotech focusing on developing innovative immunotherapies for cancer, released a public disclosure on December 30, 2020, reporting that the company obtained a U.S. patent covering its proprietary anti-PD-1 antibody.   STCube owns a proprietary platform technology directed to production of antibodies that preferentially bind to glycosylated proteins, thereby selectively masking glycosylation moieties on target proteins.  The U.S. patent, which names University of Texas (MD Anderson Cancer Center) as co-applicant, is reported to cover the company’s anti-PD-1 antibody ‘hSTM-418’.  According to the company, the antibody was developed based on the discovery that glycosylation on cell membrane proteins such as PD-1 plays critical role in the proteins’ functionality in cells.   PD-1, the target for STCube’s ‘hSTM-418’, is a well-known target for immunotherapies due to its proven functionality as an immune checkpoint.  The sales figures of Keytruda®, a blockbuster anti-PD-1 antibody from Merck, have reached $11.1 billion in 2019.   Preliminary research on ‘hSTM-418’ was previously published in the prestigious Cancer Research in March 2020.  In the publication, it was demonstrated that ‘hSTM-418’ has higher affinity to PD-1 than FDA-approved anti-PD-1 antibodies Keytruda® and Opdivo®.  It was also shown in the publication that ‘hSTM-418’ effectively neutralizes the binding between PD-1 and PD-L1, thereby stimulating anti-cancer immune reactions and providing significant prospect of increasing cancer patients’ survival period.   Spokesman for the company stated that “the grant of U.S. patent clearly shows that ‘hSTM-418’ is novel and inventive,” and the company “is in the process of manufacturing the antibody for planned clinical trials.”  “With the grant of U.S. patent,” the spokesman added, the company is “on track for market-approval and positioning ‘hSTM-418’ as a significant competition to other PD-1 products.”   The company also noted that a U.S. patent covering ‘hSTM-004’, one of its proprietary anti-PD-L1 antibodies, will issue shortly.  The spokesman indicated that the company “is very pleased with issuance of these patents, which would provide important foundation for competing with blockbuster cancer immunotherapies once the company’s products are introduced into the market.”