High-Dose Osimertinib in EGFR Exon 20 Mutation–Positive Lung Cancer
Posted: Monday, November 15, 2021
According to findings from the phase II POSITION20 study, presented during the European Society for Medical Oncology (ESMO) Congress 2021 (Abstract 1214P), high-dose treatment with osimertinib, a third-generation tyrosine kinase inhibitor, may result in antitumor activity in certain patients with non–small cell lung cancer. A.J. van der Wekken, MD, PhD, of the University Medical Center Groningen, the Netherlands, and colleagues investigated the safety and efficacy of the treatment in patients with EGFR exon 20 mutation–positive disease.
The study included 24 patients across 4 medical centers in the Netherlands between June 2018 and April 2021. Mutations between A763 and D777 were represented, with N771_H773 duplication being observed most often (n =3). Patients received 160 mg of daily osimertinib until disease progression or intolerable toxicity occurred. The objective response rate was 27%, with one patient achieving a complete response and five patients achieving a partial response. The median duration of response was 8.2 months. The best response achieved by 12 patients was stable disease, and 4 experienced disease progression. Median progression-free survival was 5.5 months; median overall survival was 15.8 months.
Half of the enrolled patients discontinued treatment due to disease progression, and two patients (8%) discontinued treatment due to grade 3 treatment-related adverse events, including pneumonitis and left ventricular systolic dysfunction. Treatment-related adverse events led five patients (21%) to receive reduced doses of 80 mg; the events included single instances of grade 3 diarrhea, grade 3 hepatotoxicity, grade 2 QTc prolongation, grade 2 nausea, and grade 2 increased creatine phosphokinase in combination with myalgia.
Disclosure: For full disclosures of the study authors, visit oncologypro.esmo.org.
