Simultaneous quantitation of befotertinib (D-0316) and its metabolite D-0865 in human plasma by LC-MS/MS method

A sensitive and reliable method was developed to determine befotertinib (D-0316) and its metabolite D-0865 from human plasma by LC-MS/MS. The samples were prepared by simple protein precipitation and 2 µL of the supernatant were chromatographed on a C18 analytical column (ACE Excel 2 Super C₁₈, 50 × 2.1 mm). Elution was performed with mobile phase A (10 mM ammonium acetate in water containing 1 % formic acid) and mobile phase B (acetonitrile containing 1 % formic acid) under a gradient program in a total run time of 4 min. Triple Quadruple 5500 equipped with Turbo Ion Spray source and multiple reaction monitoring (MRM) were used for the analysis detection. The transitions were m/z 568.3 → 72.1 m/z (befotertinib), m/z 554.2 → 497.2 (D-0865), and m/z 455.2 → 164.9 (verapamil, internal standard). According to the Chinese Pharmacopeia Commission and ICH Harmonised Guideline for Bioanalytical Method Validation, this method was validated within the spectrum of its accuracy, precision, selectivity, linearity, recovery, matrix effect, and stability. This LC-MS/MS method was successfully applied for the quantitation of befotertinib and its metabolite D-0865 in human plasma during the pharmacokinetics study of befotertinib in non-small cell lung cancer (NSCLC) patients.

Efficacy and safety of befotertinib (D-0316) in patients with EGFR T790M mutated non-small cell lung cancer that had progressed after prior EGFR TKI therapy: A phase 2, multicenter, single-arm, open-label study

INTRODUCTION

Befotertinib (D-0316) is a novel, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). This study evaluated befotertinib in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) who developed an EGFR T790M mutation after progression on first- or second-generation EGFR TKI therapy.

METHODS

This was a single-arm, open-label, phase 2 study at 49 hospitals across mainland China. Patients with locally advanced or metastatic NSCLC harboring EGFR T790M mutations with disease progression following prior first- or second- generation EGFR TKI therapy received oral befotertinib of 50 mg (cohort A) or 75-100 mg (cohort B) once daily. The primary endpoint was objective response rate (ORR) assessed by an independent review committee (IRC) in intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT03861156.

RESULTS

A total of 176 patients and 290 patients were included in cohorts A (50 mg) and B (75-100 mg), respectively. At data-cutoff (August 15, 2021), IRC-assessed ORR was 67.6% (95% confidence interval [CI]: 61.9%-72.9%) in cohort B. The investigator-assessed ORR was 54.0% (95% CI: 46.3%-61.5%) in cohort A and 65.9% (95% CI: 60.1%-71.3%) in cohort B. Investigator-assessed disease control rate was 93.2% (95% CI: 88.4%-96.4%) in cohort A and 94.8% (95% CI: 91.6%-97.1%) in cohort B. Investigator-assessed intracranial ORR was 26.7% (95% CI: 7.8%-55.1%) in cohort A and 57.1% (95% CI: 34.0%-78.2%) in cohort B. The median investigator-assessed progression-free survival (PFS) was 11.0 (95% CI: 9.6-12.5) months in cohort A and 12.5 (95% CI: 11.1-13.8) months in cohort B. The median investigator-assessed intracranial PFS was 16.5 (95% CI: 8.6-not evaluable [NE]) months in cohort A and NE (95% CI: 13.8-NE) in cohort B. The overall survival was immature. Grade 3 or higher treatment-related adverse events and treatment-related serious adverse events occurred in 20.5% and 11.4% of patients in cohort A, and in 29.3% and 10.0% of patients in cohort B, respectively.

CONCLUSION

Befotertinib of 75-100 mg has satisfying efficacy and manageable toxicity in patients with locally advanced or metastatic NSCLC harboring T790M mutation with resistance to first- or second- generation EGFR TKIs. A phase 3 randomized trial is underway (NCT04206072).