OCEANiC will investigate whether, following surgery for local or locally advanced EGFR+ NSCLC, patients with tumours containing certain types of genetic signatures can achieve the same disease-free survival with osimertinib treatment alone, as has previously been achieved with osimertinib and chemotherapy. Standard of care treatment is evolving to include osimertinib in addition to chemotherapy, but the OCEANiC trial may provide evidence for similar benefits for using the drug alone, with less toxicity, improved quality of life and reduced health care costs.