This study provides a novel targeted strategy for late-line treatment of mCRC, supporting c-MET protein expression as a biomarker for patient stratification, offering significant reference value for the design of future clinical trials.
Literature Overview
The article titled 'Phase I Study of Telisotuzumab Adizutecan (Temab-A, ABBV-400), a Novel c-Met Antibody-Drug Conjugate, in Patients With Late-Line Colorectal Cancer and Advanced Solid Tumors,' published in the 'Journal of Clinical Oncology,' systematically investigates the safety, pharmacokinetics, and preliminary efficacy of the novel antibody-drug conjugate Temab-A in patients with advanced solid tumors, particularly microsatellite stable (MSS) and BRAF wild-type metastatic colorectal cancer (mCRC). Utilizing a dose-escalation and expansion design, the study establishes a recommended phase II dose and explores the correlation between c-MET protein expression and treatment efficacy, providing critical evidence for further clinical development.Background Knowledge
For patients with metastatic colorectal cancer (mCRC) who progress after standard therapies, treatment options are extremely limited. In particular, for those with microsatellite stable (MSS) and BRAF wild-type tumors, the median progression-free survival (PFS) with current third-line therapy is less than 6 months, indicating a significant unmet clinical need. Although targeted therapies have achieved breakthroughs in other cancers, effective precision targets for mCRC remain scarce. The c-MET signaling pathway is highly expressed in approximately 50%–70% of mCRC cases and is associated with tumor invasiveness and poor prognosis, making it a promising therapeutic target. However, small-molecule c-MET inhibitors have shown limited efficacy in mCRC, possibly due to tumor heterogeneity and bypass activation of signaling pathways. Therefore, the use of antibody-drug conjugates (ADCs), which deliver cytotoxic agents selectively to tumor cells via c-MET targeting, represents a promising new approach to overcome the limitations of conventional targeted therapies. Temab-A was designed based on this concept, combining an anti–c-MET antibody with a topoisomerase I inhibitor (Top1i) payload to achieve potent and selective tumor cell killing.
Research Methods and Experiments
The study employed an open-label, multicenter phase I design with dose-escalation and mCRC dose-expansion stages. In the dose-escalation phase, patients with advanced solid tumors were enrolled to evaluate the safety and tolerability of various Temab-A doses (1.6–6.0 mg/kg Q3W) using the Bayesian Optimal Interval (BOIN) design, with primary endpoints being dose-limiting toxicity (DLT) and maximum tolerated dose (MTD). In the mCRC expansion cohort, BRAF wild-type, MSS patients were randomized to receive 1.6, 2.4, or 3.0 mg/kg Q3W to assess efficacy and further confirm safety. All patients underwent retrospective IHC testing for c-MET protein expression using the SP44 antibody, with positivity defined as ≥10% of tumor cells showing 3+ staining. Pharmacokinetic (PK) analyses included half-life and exposure of conjugated drug, total antibody, and free payload. Key efficacy endpoints included objective response rate (ORR), disease control rate (DCR), duration of response (DOR), PFS, and OS.Key Conclusions and Perspectives
Research Significance and Prospects
This study establishes the recommended phase II dose (RP2D) of Temab-A in mCRC as 2.4 mg/kg Q3W, balancing efficacy and long-term tolerability, providing a solid foundation for future phase II trials. Mechanistically, Temab-A achieves targeted delivery via ADC, overcoming limitations of traditional small-molecule inhibitors, representing a new paradigm in c-MET–targeted therapy. Biomarker analyses reinforce the application of precision medicine in mCRC, suggesting that patient selection based on c-MET IHC testing could identify those most likely to benefit.
From a drug development perspective, the success of Temab-A offers new insights for treating other c-MET–overexpressing cancers (e.g., NSCLC, GEA). Its Top1i payload, distinct from conventional chemotherapy, may overcome resistance to irinotecan. Future studies should explore its potential in combination with immunotherapy or other targeted agents, particularly in immunologically cold tumors such as MSS/pMMR mCRC.
Conclusion
This study reports, for the first time, phase I clinical data of the c-MET–targeting ADC Temab-A in patients with advanced colorectal cancer, confirming its manageable safety profile and notable antitumor activity in heavily pretreated mCRC patients. The recommended phase II dose of 2.4 mg/kg Q3W demonstrates a favorable efficacy trend while maintaining high relative dose intensity, outperforming existing therapies. Critically, the study validates a positive correlation between c-MET protein expression levels and treatment response, providing strong biomarker evidence for precise patient selection. These findings not only fill a critical gap in targeted therapy for late-line mCRC but also advance the application of ADCs in gastrointestinal malignancies. From bench to bedside, the successful development of Temab-A exemplifies a complete translational pathway—from target discovery and drug design to biomarker-driven clinical trials. Future validation in larger phase III trials, along with head-to-head comparisons against current standard therapies, will determine whether Temab-A can become a new standard of care for third-line mCRC. Additionally, this study offers important reference for ADC-based therapeutic strategies in other c-MET–driven cancers, demonstrating broad translational value.
