Retrospective analysis of CNS outcomes of osimertinib plus chemotherapy for EGFR mutation-positive NSCLC beyond progression on osimertinib

Central nervous system (CNS) metastases are common among patients with EGFR mutation-positive NSCLC. A retrospective study of patients of Prince of Wales Hospital of the Chinese University of Hong Kong compared real-world CNS progression-free survival with osimertinib plus platinum-based chemotherapy (OSI+ cohort) versus platinum-based chemotherapy alone (OSI- cohort) after progression on osimertinib in patients with advanced EGFR mutation-positive NSCLC and brain metastases. The rwCNS-PFS was significantly longer in the OSI+ cohort compared with the OSI- cohort (median 9.0 months versus 5.7 months; HR 0.37; p=0.007). This remained significant after adjustment for EGFR mutation, line of osimertinib treatment, prior radiotherapy, and CNS progression on osimertinib monotherapy. The probability of CNS progression at 6 months was 5.6% in the OSI+ cohort versus 20.9% in the OSI- cohort. Incidence of salvage radiotherapy to the brain was lower in the OSI+ cohort than in the OSI- cohort (15% versus 24%). The authors conclude that in patients with EGFR mutation-positive NSCLC and brain metastases, continuing osimertinib plus chemotherapy after progression on osimertinib significantly reduced risk of CNS progression.