Osimertinib activity in patients (pts) with leptomeningeal (LM) disease from non-small cell lung cancer (NSCLC): Updated results from BLOOM, a phase I study.

Abstract

9002Background: LM disease is a severe type of NSCLC disease progression, associated with poor prognosis. Osimertinib (AZD9291) is an oral, potent, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) selective for activating (EGFRm) and T790M resistance mutations. We present updated data from a phase I study, BLOOM (NCT02228369), of osimertinib in pts with LM disease from EGFRm NSCLC. Methods: Pts with EGFRm advanced NSCLC who had progressed on prior EGFR-TKI therapy and LM disease confirmed by positive cerebrospinal fluid (CSF) cytology were enrolled. Pts were treated with osimertinib 160 mg, once daily. Response was assessed based on CSF cytology, intracranial (IC) imaging, and neurological examination. EGFRm DNA in CSF was determined by Droplet Digital PCR. Results: As of December 30, 2015, 20 pts were dosed, of whom 7 were dosed for ≤ 3 weeks. Maximum treatment duration was 37 weeks. Of 12 pts reaching a 12-week IC image assessment, 7 had radiological improvement, 2 had ...