Hypothesize, that in patients with on-label osimertinib 1st-line treatment of stage IIIB or IV NSCLC, a biomarker-driven escalation of osimertinib therapy with a platinum-based chemotherapy regimen will effectively enhance PFS and subsequently OS. Lack of EGFRm clearance after an osimertinib treatment period of 3 weeks as assessed by liquid biopsy will be used to predict sub-optimal response. In these patients, treatment will be escalated after approx. 7 weeks of on-label osimertinib monotherapy by adding up to 4 cycles of a combination regimen of pemetrexed and cisplatin or carboplatin. Patients with complete EGFR plasma clearance will continue to receive standard of care osimertinib and will not be eligible for the study. Primary outcome measure will be PFS, which will be compared to historical data on TKI monotherapy from persistent EGFR shedder from the FLAURA trial.
PACE is a prospective multicenter single-arm investigator-initiated phase II trial that examines the value of a treatment escalation strategy by the addition of platinum-based doublet chemotherapy to osimertinib in patients with treatment-naïve NSCLC harboring L858R or del19 EGFR mutation who are suspected to have poor response upon single-agent TKI treatment.