In this real-world study, clinical modality of osimertinib resistance in patients with pretreated advanced NSCLC was mainly intrathoracic failure.

For patients experiencing progression on osimertinib, subsequent chemotherapy showed a trend for prolonged survival in a non-selected population, suggesting that chemotherapy is an effective post-resistance treatment option.

Continued osimertinib beyond progressive disease provided additional clinical benefit, but showed no overall survival benefit compared with patients who discontinued osimertinib in the non-selected population.