SUMMARY: The FDA on May 14, 2025, granted accelerated approval to Telisotuzumab vedotin-tllv (EMRELIS®), a c-Met-directed antibody and microtubule inhibitor conjugate, for adults with locally advanced or metastatic, non-squamous Non-Small Cell Lung Cancer (NSCLC) with high c-Met protein overexpression [50% or more of tumor cells with strong (3+) staining], as determined by an FDA-approved test, who have received a prior systemic therapy. FDA also approved the VENTANA MET (SP44) RxDx Assay (Roche Diagnostics) as a companion diagnostic test to aid in detecting c-Met protein overexpression in patients with non-squamous NSCLC who may be eligible for treatment with Telisotuzumab vedotin .
The American Cancer Society estimates that for 2025, about 226,650 new cases of lung cancer will be diagnosed and 124,730 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers and Adenocarcinoma is now the most frequent histologic subtype of lung cancer.
Background
The MET proto-oncogene encodes the receptor tyrosine kinase c-Met, a key regulator of tumor cell proliferation, survival, invasion, and angiogenesis. Dysregulation of MET signaling can occur in NSCLC via gene amplification (about 5% of cases), exon 14 skipping mutations (about 2%-4%), or through c-Met protein overexpression, which is observed in approximately one-quarter to one-third of patients. Notably, c-Met protein overexpression represents a negative prognostic marker in both early and advanced NSCLC, particularly in nonsquamous, EGFR-wildtype disease, yet no therapies have been approved to directly address this biomarker.
Telisotuzumab vedotin (Teliso-V; EMRELIS®) is a first-in-class, c-Met–directed antibody-drug conjugate (ADC). It couples a c-Met–binding monoclonal antibody with the microtubule-disrupting agent MonoMethyl Auristatin E (MMAE) through a cleavable linker. Preclinical work showed that tumoricidal activity requires high levels of c-Met expression (>100,000 receptors per cell), which supports patient selection strategies for clinical use.
The LUMINOSITY Trial Design
LUMINOSITY study (NCT03539536) is an ongoing, nonrandomized, two-stage, Phase II, multicenter trial designed to identify and validate the NSCLC populations most likely to benefit from Teliso-V monotherapy in the second-line or third-line setting, and then to expand the groups to further evaluate efficacy in the selected populations.
- Stage I: Patients were enrolled into three cohorts based on histology and EGFR mutation status: (1) nonsquamous EGFR-wildtype NSCLC, (2) nonsquamous EGFR-mutant NSCLC, and (3) squamous NSCLC.
- Stage II: Only the nonsquamous EGFR-wildtype NSCLC cohort fulfilled expansion criteria and was carried forward for further evaluation.
Biomarker Definition:
- Nonsquamous NSCLC: c-Met protein overexpression defined as 25% or more of tumor cells showing 3+ membrane staining intensity (with high expression 50% or more and intermediate expression 25-less than 50%).
- Squamous NSCLC: a broader cutoff was applied (75% or more of tumor cells at any intensity) given generally lower c-Met expression levels.
Treatment regimen: Teliso-V was administered intravenously at 1.9 mg/kg every 2 weeks.
Endpoints: The Primary endpoint was Overall Response Rate (ORR) by Independent Central Review (ICR). Secondary endpoints included Duration of Response (DOR), Disease Control Rate (DCR), Progression-Free Survival (PFS), Overall Survival (OS), and Safety.
Key Efficacy Results in the Nonsquamous EGFR-wildtype NSCLC Cohort
As of February 21, 2024, 172 patients had received at least one dose of Teliso-V, with 168 patients (N=168) included in efficacy analyses (c-Met high, N=84, c-Met intermediate, N=84). The majority (97.6%) had previously received platinum-based chemotherapy, and nearly 80% had also received immune checkpoint inhibitors (ICIs).
- Overall Response Rate (ORR):
- Total c-Met overexpressing population: 29.2%
- High expression: 34.5%
- Intermediate expression: 23.8%
- Median Duration of Response (DOR):
- Overall: 7.2 months
- High expression: 9.0 months
- Intermediate expression: 7.2 months
Responses were consistent across patients pretreated with platinum alone or with both platinum and ICI, suggesting durability irrespective of prior therapy type.
Safety Profile
The safety of Teliso-V was generally manageable and consistent with its mechanism of action.
- Most common treatment-related adverse events (any grade): peripheral sensory neuropathy (31%), peripheral edema (16%), and fatigue (14%).
- Most common grade 3 or more TRAE: peripheral sensory neuropathy (7%).
These findings align with the known toxicity profile of MMAE-based ADCs, highlighting neuropathy as the principal dose-limiting concern.
Limitations and Next Steps
While encouraging, the Phase II design lacked a comparator arm, limiting definitive conclusions about comparative efficacy. A randomized, Phase III trial, TeliMET NSCLC-01 (NCT04928846), is underway, directly comparing Teliso-V against Docetaxel in previously treated, c-Met–overexpressing, nonsquamous EGFR-wildtype NSCLC. Additionally, exploratory biomarker analyses may help refine patient selection, particularly given potential overlap between c-Met protein expression and other MET pathway genomic alterations.
Clinical Implications
LUMINOSITY demonstrates that Teliso-V can achieve durable clinical responses in a biomarker-selected subset of NSCLC patients who currently lack targeted treatment options. Response enrichment among patients with high c-Met protein expression reinforces the relevance of robust biomarker screening in clinical practice. Teliso-V represents the first therapy specifically directed against c-Met protein overexpression in NSCLC, addressing an important unmet need.
LUMINOSITY, a phase 2 study of telisotuzumab vedotin in patients with c-Met protein–overexpressing non-squamous EGFR-wildtype advanced NSCLC: Efficacy outcomes by prior therapy. Goldman JW, Lu S, Bar J, et al. Journal of Clinical Oncology. Volume 43, Number 16_suppl. https://doi.org/10.1200/JCO.2025.43.16_suppl.8618
