STCube, a bio company specializing in development of anti-cancer immunotherapies, on the 12th that research findings regarding its proprietary immune-checkpoint inhibitor STM418, which is being developed as a candidate for novel immunotherapy for cancer, were published in Cancer Research, a highly-regarded cancer research journal.

STM418, the subject of this publication, is a PD-1 antibody that was developed based on the novel finding that glycosylation on immune-checkpoint protein PD-1 is critical for its functions. STCube has conducted a research project on STM418 in cooperation with U.S. based MD Anderson Cancer Center (MDACC) and Taiwan-based China Medical University. The publication is drawing a keen attention in medical circles.

Having recognized that the glycosylation on PD-1 is critical to the protein’s functions, STCube analyzed each of the glycosylation sites on PD-1. As a result, it was discovered that glycosylated PD-1 remain on the surface of cells for a long period of time with enhanced stability, and that among the glycosylation sites on PD-1, N58 significantly contributes to PD-1’s binding to PD-L1.

STM418, which selectively recognizes glycosylated PD-1, exhibited a higher binding affinity to PD-1 than other PD-1 antibodies approved by the U.S. FDA, a likely reason for STM418’s showing of better anticancer efficacies. The results from animal testing are in accord, showing that STM418 prevented the tumor growth better than other PD-1 antibodies, and that the cancerous animals treated with STM418 survived longer than the animals treated with other PD-1 antibodies.

Among immune-checkpoint inhibitors, PD-1 antibodies are generally regarded as a backbone therapy for cancer patients, and Keytruda, one of the most successful PD-1 antibodies, single-handedly achieved annual sales amounting to about 13.15 trillion Korean won last year. As STM418 shows better anticancer efficacies than existing PD-1 antibodies, the expectation is that once it is commercialized, its impact on the market would be significant.

One official of the company stated: “We are pleased that the paper on STM418 for which STCube researchers are named as co-authors has been published in Cancer Research. Now that the excellent anticancer efficacies of STM418 have been recognized in academic circles, we plan to move forward with development of this antibody in clinical settings, ultimately to introduce an innovative anticancer immunotherapy to the market."

He also added: “In addition to the STT-003 antibody, which was introduced R&D IR event in the U.S. last month, we also plan to seek FDA approval for clinical trials (IND) and conduct Phase 1 clinical trials on STM418. We will do our utmost to move forward as quickly as possible." <End>