MUNICH – The experimental agent capmatinib was associated with a high response rate when used in the first line for patients with advanced non–small cell lung cancers bearing MET exon 14–skipping mutations, said investigators in the
Among a cohort of 25 patients with treatment-naive, MET exon 14–mutated non–small cell lung cancer (NSCLC), the primary endpoint of overall response rate (ORR) as determined by blinded, independent reviewers was 72%.
In contrast, the ORR among 69 patients who had received one or more prior lines of therapy was 39.1%, reported, of University Hospital Cologne (Germany).
“The differential benefit observed between patients treated in the first line and relapsed [settings] highlights the need of early diagnosis of this aberration, and prompt targeted treatment of this challenging patient population,” he said at the European Society for Medical Oncology Congress.
MET exon14–skipping mutations occur in approximately 3%-4% of NSCLC cases. The mutation is thought to be an oncogenic driver and has been shown to be a poor prognostic factor for patients with advanced NSCLC. Patients with this mutation have poor responses to conventional therapy and immune checkpoint inhibitors, even when their tumors have high levels of programmed death–ligand 1 (PD-L1) and high mutational burden, Dr. Wolf said.
Capmatinib (INC280) is an oral, reversible inhibitor of the MET receptor tyrosine kinase and is highly selective for MET, with particular affinity for MET exon 14 mutations. It is also capable of crossing the blood-brain barrier and has shown activity in the brain in preliminary studies.
The Geometry MONO-1 trial is a phase 2 study of capmatinib in patients with stage IIIB/IV NSCLC with tumors that demonstrate MET amplification and/or carry the MET exon 14 mutation. Three study cohorts of patients with MET amplification were closed for futility. Dr. Wolf reported results from two cohorts of patients with MET exon 14–skipping mutations regardless of gene copy number: one with treatment-naive patients and the other with patients being treated in the second or third line.
As noted, the ORR in 25 patients in the treatment-naive cohort after a median follow-up of 5.6 months was 72%, including 18 partial responses and no complete responses. In addition, six patients (24%) had stable disease, for a disease control rate of 96%.
In the pretreated cohort, however, there were no complete responses among 69 patients, and 27 patients (39.1%) had partial responses. In this cohort, an additional 26 patients (37.7%) had stable disease, for an ORR of 39.1% and disease-control rate of 78.3%.
Dr. Wolf also highlighted preliminary evidence of capmatinib activity in the brain. He noted that one patient, an 80-year-old woman with multiple untreated brain metastases as well as lesions in dermal lymph nodes, liver, and pleura, had complete resolution of brain metastases at the first postbaseline CT scan, 42 days after starting capmatinib. The duration of response was 11.3 months, at which point the patient discontinued the drug because of extracranial progressive disease.
Among all patients in all study cohorts (302) the most common grade 3 or 4 adverse events were peripheral edema, dyspnea, fatigue, nausea, vomiting, and decreased appetite. Adverse drug-related events (grade 3 or 4) included peripheral edema, nausea, vomiting, fatigue, and decreased appetite. In all, 10.3% of patients discontinued for adverse events suspected to be related to capmatinib.
Invited discussant, from the National Taiwan University Hospital in Taipei, said that the study shows that the MET exon 14–skipping mutation is an oncogenic driver and that capmatinib is an effective tyrosine kinase inhibitor (TKI) for patients with NSCLC harboring this mutation.
Questions that still need to be answered, he said, include whether patients with the mutation are heterogeneous and may have differing response to TKIs, how long the duration of response is, how long it will take for resistance to capmatinib to occur, how it compares with other MET inhibitors, and if there are additional biomarkers that could help select patients for treatment with the novel agent.
The study was funded by Novartis. Dr. Wolf reported advisory board participation, institutional research support, and lecture fees from Novartis and others. Dr. Yang reported honoraria from advisory board participation and/or speaking from Novartis and others. His institution participated in the Geometry MONO-1 study, but he was not personally involved.