Treatment Rationale and Design of a Phase III Study of Afatinib or Chemotherapy in Patients with Non–small-cell Lung Cancer Harboring Sensitizing Uncommon Epidermal Growth Factor Receptor Mutations (ACHILLES/TORG1834)

We describe the treatment rationale and design of our randomized phase III study, the ACHILLES trial (Japan Registry of Clinical Trials: jRCTs031180175). The aim of this study is to investigate the superiority of afatinib over chemotherapy as first-line treatment in patients with advanced nonsquamous non–small-cell lung cancer with sensitizing uncommon or compound epidermal growth factor receptor (EGFR) mutations, with the exception of de novo T790M mutations and exon 20 insertions. Eligible patients will be randomized at a 1:2 ratio to receive either chemotherapy or afatinib until disease progression or unacceptable toxicity. Patients in the chemotherapy arm will receive pemetrexed 500 mg/m² + cisplatin 75 mg/m² or carboplatin area under the curve (AUC) 5 or 6 every 3 weeks × 4 cycles, followed by pemetrexed 500 mg/m² every 3 weeks. In the afatinib arm, investigators will choose the starting dose of afatinib (30 mg or 40 mg orally daily). The primary endpoint is progression-free survival. A total of 106 patients will be enrolled in this trial over a 30-month registration period with a 15-month follow-up. Enrollment began in March 2019. The results of this trial will establish the superiority of afatinib over chemotherapy in a cohort with a large variety of EGFR mutations.