Savolitinib ± Osimertinib in Japanese Patients with Advanced Solid Malignancies or EGFRm NSCLC: Ph1b TATTON Part C

QT-Interval Prolongation, Torsades de Pointes, and Heart Failure With EGFR Tyrosine Kinase Inhibitors in Non-Small Cell Lung Cancer: Systematic Review

A systematic literature review was conducted to determine the incidence and mortality of QT-interval prolongation (QTp), torsades de pointes (TdP), and heart failure (HF) in patients with non-small cell lung cancer (NSCLC) who received epidermal growth factor receptor (EGFR) TKIs. Of 296 identified publications, 95 met eligibility criteria and were abstracted for QTp/TdP and HF outcomes (QTp/TdP: 83 publications, including 5 case study publications; HF: 79 publications, including 6 case study publications [involving 8 patients]). QTp incidence ranged from 0% to 27.8% in observational studies and from 0% to 11% in clinical trials, with no deaths due to QTp. There were no TdP events or deaths due to TdP. The incidence of HF ranged from 0% to 8%, and HF mortality rates ranged from 0% to 4%. Patients receiving treatment with EGFR TKIs should be monitored for signs of QTp, TdP, and HF per prescribing information. Standardized definitions and methods to improve monitoring of QTp, TdP, and HF-related events are needed in patients with NSCLC.

MET Inhibitor Capmatinib Radiosensitizes MET Exon 14-Mutated and MET-Amplified Non-Small Cell Lung Cancer

PURPOSE

The objective of this study was to investigate the effects of inhibiting the MET receptor with capmatinib, a potent and clinically relevant ATP-competitive tyrosine kinase inhibitor, in combination with radiation in MET exon 14-mutated and MET-amplified non-small cell lung (NSCLC) cancer models.

METHODS AND MATERIALS

In vitro effects of capmatinib and radiation on cell proliferation, colony formation, MET signaling, apoptosis, and DNA damage repair were evaluated. In vivo tumor responses were assessed in cell line xenograft and patient-derived xenograft models. Immunohistochemistry was used to confirm the in vitro results.

RESULTS

In vitro clonogenic survival assays demonstrated radiosensitization with capmatinib in both MET exon 14-mutated and MET-amplified NSCLC cell lines. No radiation-enhancing effect was observed in MET wild-type NSCLC and a human bronchial epithelial cell line. Minimal apoptosis was detected with the combination of capmatinib and radiation. Capmatinib plus radiation compared with radiation alone resulted in inhibition of DNA double-strand break repair, as measured by prolonged expression of γH2AX. In vivo, the combination of capmatinib and radiation significantly delayed tumor growth compared with vehicle control, capmatinib alone, or radiation alone. Immunohistochemistry indicated inhibition of phospho-MET and phospho-S6 and a decrease in Ki67 with inhibition of MET.

CONCLUSIONS

Inhibition of MET with capmatinib enhances the effect of radiation in both MET exon 14-mutated and MET-amplified NSCLC models.

Chinese multidisciplinary expert consensus on the management of adverse drug reactions associated with savolitinib

Savolitinib is a highly selective mesenchymal-epithelial transition (MET) tyrosine kinase inhibitor (TKI). Based on its significant efficacy shown in clinical studies, savolitinib was conditionally approved for marketing in China on 22 June 2021, for the treatment of advanced non-small cell lung cancer (NSCLC) with MET 14 exon skipping mutation. Additionally, many studies showed that MET TKIs were equally effective in patients with advanced solid tumors with MET gene amplification or MET protein overexpression. Several relevant registered clinical studies are in progress. The most common adverse reactions (ARs) due to savolitinib administration are nausea, vomiting, peripheral edema, pyrexia, and hepatotoxicity. This consensus was developed through two rounds of extensive national surveys involving multidisciplinary experts in China, aiming to guide clinicians to prevent and treat various ARs scientifically, and improve the efficacy of the drug and the quality of life of patients.

MET Inhibitor Capmatinib Radiosensitizes MET Exon 14-Mutated and MET-Amplified Non-Small Cell Lung Cancer

Purpose

The objective of this study was to investigate the effects of inhibiting the MET receptor with capmatinib, a potent and clinically relevant ATP-competitive tyrosine kinase inhibitor, in combination with radiation in MET exon 14-mutated and MET-amplified non-small cell lung (NSCLC) cancer models.

Methods and Materials

In vitro effects of capmatinib and radiation on cell proliferation, colony formation, MET signaling, apoptosis, and DNA damage repair were evaluated. In vivo tumor responses were assessed in cell line xenograft and patient-derived xenograft models. Immunohistochemistry (IHC) was used to confirm in vitro results.

Results

In vitro clonogenic survival assays demonstrated radiosensitization with capmatinib in both MET exon 14-mutated and MET-amplified NSCLC cell lines. No radiation-enhancing effect was observed in MET wild-type NSCLC and human bronchial epithelial cell line. Minimal apoptosis was detected with the combination of capmatinib and radiation. Capmatinib plus radiation compared to radiation alone resulted in inhibition of DNA double-strand break repair as measured by prolonged expression of γH2AX. In vivo, the combination of capmatinib and radiation significantly delayed tumor growth compared to vehicle control, capmatinib alone, or radiation alone. IHC indicated inhibition of phospho-MET and phospho-S6 and a decrease in Ki67 with inhibition of MET.

Conclusions

Inhibition of MET with capmatinib enhanced the effect of radiation in both MET exon 14-mutated and MET-amplified NSCLC models.

Osimertinib + Savolitinib to Overcome Acquired MET-Mediated Resistance in Epidermal Growth Factor Receptor-Mutated, MET-Amplified Non-Small Cell Lung Cancer: TATTON

MET-inhibitor and EGFR tyrosine kinase inhibitor (EGFR-TKI) combination therapy could overcome acquired MET-mediated osimertinib resistance. We present the final phase Ib TATTON (NCT02143466) analysis (Part B, n = 138/Part D, n = 42) assessing oral savolitinib 600 mg/300 mg once daily (q.d.) + osimertinib 80 mg q.d. in patients with MET-amplified, EGFR-mutated (EGFRm) advanced non-small cell lung cancer (NSCLC) and progression on prior EGFR-TKI. An acceptable safety profile was observed. In Parts B and D, respectively, objective response rates were 33% to 67% and 62%, and median progression-free survival (PFS) was 5.5 to 11.1 months and 9.0 months. Increased antitumor activity may occur with MET copy number ≥10. EGFRm circulating tumor DNA clearance on treatment predicted longer PFS in patients with detectable baseline ctDNA, while acquired resistance mechanisms to osimertinib + savolitinib were mediated by MET, EGFR, or KRAS alterations.

SIGNIFICANCE

The savolitinib + osimertinib combination represents a promising therapy in patients with MET-amplified/overexpressed, EGFRm advanced NSCLC with disease progression on a prior EGFR-TKI. Acquired resistance mechanisms to this combination include those via MET, EGFR, and KRAS. On-treatment ctDNA dynamics can predict clinical outcomes and may provide an opportunity to inform earlier decision-making. This article is highlighted in the In This Issue feature, p. 1.