STCube Announces Clinical Plans for Small Cell Lung Cancer and Colorectal Cancer Combination Therapy at SITC 2023

STCube announced on the 6th that it made a focused presentation at the Society for Immunotherapy of Cancer (SITC) in the United States about the upgraded multiplex immunofluorescence platform for the clinical phase 1b/2 trial of Nelmastobart (hSTC810).

SITC is the largest global conference in the field of immuno-oncology. It has over 4,600 clinicians, scientists, and researchers from 63 countries worldwide as members. This year's event was held from the 1st to the 5th of this month in San Diego, USA.

STCube confirmed the efficacy of the combination therapy of Nelmastobart and paclitaxel through its independently developed zebrafish xenograft model and 3D culture system (spheroid culture). Additionally, the results obtained from these two models were finally validated in tumor mouse models, establishing a platform capable of safety and pharmacokinetic evaluation.

An STCube representative said, “Through these three platforms, the therapeutic effect of the BTN1A1-inhibiting antibody Nelmastobart can be efficiently observed. We will actively utilize this to propose new treatment strategies based on the characteristics of BTN1A1 and PD-L1, and demonstrate them in the upcoming phase 2 clinical trials targeting small cell lung cancer and colorectal cancer.”

STCube has consecutively demonstrated that BTN1A1 is a novel immune checkpoint protein and a potential target for new immuno-oncology drugs. BTN1A1 shows an exclusive expression pattern compared to the representative immune checkpoint protein PD-L1, which is expected to benefit patients who do not respond to anti-PD-1/PD-L1 therapies.

The BTN1A1 antibody Nelmastobart successfully completed phase 1 clinical trials in patients with advanced solid tumors. It showed excellent tolerability with no dose-limiting toxicity (DLT) up to the final phase 1 dose of 15 mg/kg, and demonstrated antitumor activity with one partial response (PR) and 13 stable disease (SD) cases.

STCube is currently preparing phase 1b/2 clinical trials targeting patients with small cell lung cancer (SCLC) and colorectal cancer. They have characterized patient tumor biopsy slides according to BTN1A1/PD-L1 expression to build a predictive model for Nelmastobart’s therapeutic effect. To understand the heterogeneity of interaction mechanisms between immune cells and cancer cells, zebrafish, organoid, and mouse models were used as various evaluation platforms.

An STCube representative stated, “We confirmed that Nelmastobart is effective in SCLC patients with high BTN1A1 expression and low PD-L1 expression. Through this platform analysis, we also found that the expression of YAP, another biomarker in SCLC patients who responded to Nelmastobart treatment, is similar to that of BTN1A1.”

They added, “The IRBs (Institutional Review Boards) of the clinical participating hospitals are being finalized, and we plan to start patient recruitment soon to begin dosing the first patient within this year. As the clinical trials progress, interest from global big pharma companies is increasing, and various partnership discussions are ongoing.”

This content was produced with the assistance of AI translation services.