Patients with EGFR-mutant (m) non-small-cell lung cancer (NSCLC) and leptomeningeal metastases (LM) respond favorably to high daily doses of osimertinib, phase 1 BLOOM study data suggest.
Myung-Ju Ahn (Sungkyunkwan University School of Medicine, Seoul, Republic of Korea) and study co-authors say that “osimertinib has the potential to become a treatment option for patients with EGFRm NSCLC and LM previously treated with EGFR-TKI [tyrosine kinase inhibitor].”
Between April 2015 and October 2017, 41 patients whose disease had previously progressed on EGFR–TKI therapy were enrolled in the BLOOM trial. All patients received osimertinib 160 mg orally once a day for a median of 8.1 months, during which radiologic assessments were performed every 6 weeks, starting at baseline. There were 29 patients who had co-existing brain metastases, and consequently 20 of these patients had previously received brain radiotherapy.
Investigator assessment found that one patient achieved LM complete response, while neuroradiologic blinded independent central review (BICR) available for 37 patients identified 12 as achieving an LM complete response. An LM partial response was seen in 10 and 11 patients as determined by investigator and BICR, respectively, and the corresponding objective response rates (ORRs) were 27% and 62%.