[ASCO 2025] TiUM Bio proves potential for offering new drug for biliary, head, and neck cancer

CHICAGO, Ill. – By Hong Sook / Korea Biomedical Review correspondent -- TiUM Bio has become the only Korean company to be featured in the Trials in Progress (TPS) session at the American Society of Clinical Oncology 2025 Annual Meeting (ASCO 2025), attracting the attention of global oncology experts.

At ASCO 2005, which was held in Chicago, U.S.A., from last Friday to Tuesday (local time), TiUM Bio unveiled some of the clinical data from the phase 2 clinical trial of TU2218 in combination with Keytruda (pembrolizumab).

TU2218 is a dual inhibitor that simultaneously blocks the transforming growth factor (TGF-ß) and vascular endothelial growth factor (VEGF) pathways in the body that interfere with the activity of immuno-oncology drugs, including Keytruda.

The presented trial was designed to determine the synergistic potential of co-administering TU2218 and Keytruda to increase response rates to Keytruda by modulating the tumor microenvironment and immune activation.

According to the presentation, in the head and neck cancer (HNSCC) cohort on first-line therapy, seven of 11 evaluable patients achieved a Partial Response (PR), and one achieved a Stable Disease (SD) response.

In the second-line biliary tract cancer (BTC) cohort, meaningful antitumor responses were observed, with four of 23 evaluable patients achieving a partial response and seven achieving a stable disease response. Korea Biomedical Review caught up with TiUm Bio CEO Kim Hun-taek at ASCO 2025 to discuss the implications of these data and future development plans.

Question: What are the implications of the TU2218 phase 2 results?

Answer: I think seeing partial remission in seven out of 11 patients with head and neck cancer is very encouraging. Based on these results, I think it could be used as a first-line treatment for head and neck cancer, where there are not many treatment options.

Four out of 23 patients with biliary tract cancer achieved partial remission. This is encouraging, given that the standard of care for second-line treatment is the FOLFOX (fluorouracil + oxaliplatin) regimen, which has an objective response rate of 5-10 percent. Based on these data, we see an opportunity for expansion into the first-line treatment of biliary tract cancer.

These are interim phase 2 results. Based on these results, we expect to demonstrate high treatment efficacy in a well-selected phase 2b.

Q: What was the most frequent question you received from global oncology experts attending ASCO 2025 during your TPS session?

A: They noted that our compounds are small molecules. Recently, the development of bispecific antibodies has been booming, and drugs with similar mechanisms to ours are often developed as antibodies. Big Pharma has always been interested in our compounds because they can be administered less frequently than antibodies and are more convenient for patients when developed into products.

Small molecules and antibodies are modalities with advantages and disadvantages. Small molecules have a much smaller molecular weight than antibodies, so they are more permeable to tumor tissue and can be highly effective.

Q: Why did you select biliary tract cancer and head and neck cancer as indications?

A: While Keytruda is indicated for both cancers, it is only effective in select patients based on biomarkers. In head and neck cancer, the response rate to pembrolizumab plus chemotherapy and the existing EXTREME regimen (cetuximab plus chemotherapy) is around 36 percent.

In this situation, the mechanism of action of TU2218 may sufficiently increase the efficacy of existing immuno-oncology drugs, including pembrolizumab, so we conducted clinical trials in this cancer type. We currently have preclinical data on several other cancers, so we will provide data that can be expanded to other cancers if the technology is transferred.

Q: As Merck and others have shown, the development of additional TGF-β inhibitors to overcome PD-(L)1 refractoriness has been slow. What is your development strategy for TU2218 in this situation?

A: The development trend of TGF-β inhibitors is all about balancing efficacy and toxicity. We demonstrated this safety in phase 1a, and our strategy is to control efficacy and toxicity by adjusting the dosing frequency.

Q: How will you commercialize this pipeline?

A: It's hard to specify the exact timing, but if the Big Pharma technology transfer goes through, we will sign over all rights to the material to Big Pharma. We already have detailed data that can be expanded to other cancers, so we're working on commercialization based on these clinical data.