P90.03 A Phase 2 Trial of MRTX849 in Combination with Pembrolizumab in Patients with Advanced Non-Small Cell Lung Cancer with KRAS G12C Mutation

Development and validation of a robust and sensitive HPLC-MS/MS method for the quantitation of MRTX849 in plasma and its application in pharmacokinetics

MRTX849 is a novel, highly selective, targeted inhibitor of KRAS (G12C), which significantly improves the objective response rate in patients with advanced solid tumors. However, neither an analytical HPLC-MS/MS assay nor pharmacokinetics has been reported for MRTX849 in plasma. In the present study, chromatography was accomplished on a reversed phase C₁₈ column (50 × 2.1 mm, 3.5 μm). The limit of detection of MRTX849 was 0.02 ng mL^-1 at S/N ≥ 3. Only 20 μL of plasma was utilized for accurate quantitation. The optimized analytical assay was fully validated and verified in accordance with guidelines. The calibration curve for MRTX849 was linear with a correlation coefficient >0.99 in the range of 0.05-200 ng mL^-1. The intra- and inter-day accuracy and precision were all within ±10%. The matrix effect and recovery were consistent and acceptable under several quality control concentrations. This HPLC-MS/MS method was successfully applied for a pharmacokinetic study of MRTX849 at a dose of 15 mg kg^-1.

Selective KRAS G12C inhibitors in non-small cell lung cancer: chemistry, concurrent pathway alterations, and clinical outcomes

Cancers harboring mutations in the Kirsten rat sarcoma homolog (KRAS) gene have been associated with poor prognosis and lack of targeted therapies. KRAS mutations occur in approximately one in four patients diagnosed with non-small cell lung cancer (NSCLC) with KRAS G12C mutations harbored at approximately 11-16%. Research into KRAS-driven tumors and analytical chemistry have borne a new class of selective small molecules against the KRAS G12C isoform. Phase II data for sotorasib (AMG510) has demonstrated a 37.1% overall response rate (ORR). Adagrasib (MRTX849) has demonstrated a 45% ORR in an early study. While single agent efficacy has been seen, initial data suggest combination approaches are an opportunity to improve outcomes. Here, we present perspectives on the initial progress in targeting KRAS G12C, examine co-mutations evident in KRAS G12C NSCLC, and comment on potential future combinatorial approaches including SHP2, SOS1, MEK, EGFR, mTOR, CDK, and checkpoint blockade which are currently being evaluated in clinical trials. As of May 28, 2021, sotorasib has achieved US FDA approval for patients with KRAS G12C mutant lung cancer after one line of a prior therapy.

The rapidly evolving landscape of novel targeted therapies in advanced non-small cell lung cancer

Lung cancer is a highly heterogeneous disease often driven by well-characterized driver mutations. Although the best studied are common alterations in the epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) oncogenes, rapid advances in molecular characterization has led to the development of novel therapeutics that inhibit additional oncogenic alterations in advanced NSCLC. The literature search identified 62 eligible phase I/II clinical trials or integrated analyses of assessing novel targeted agents against the following molecular alterations: ROS1-rearranged, BRAF V600E-mutant, NTRK-rearranged, MET-altered, uncommon EGFR-mutant, RET-rearranged, HER2-positive, KRAS G12C-mutant and NRG1-rearranged. This rapidly evolving field has produced many new targeted treatment options and promising outcomes have led to the FDA approval of seven novel agents for use in ROS1-rearranged, BRAF V600E-mutant, NTRK-rearranged, MET exon 14 skipping-mutant or RET-rearranged advanced NSCLC. Research continues at a rapid pace, with a number of phase III trials underway to fully evaluate new promising agents under development for improving outcomes in patients with NSCLC harboring distinct molecular subtypes. This review will provide a comprehensive summary of existing data as well as a user-friendly guide on the current status of novel targeted therapy in oncogene-driven advanced NSCLC.