EvidenceEGFR-mutated non-small-cell lung cancer

The survival benefit first reported in 2023 has held five years after the last dose of adjuvant osimertinib, which answers the worry that a three-year course only delays relapse. Patients with an exon 19 deletion gained most; the L858R estimate crosses one and is less certain. Nothing here changes the recommendation, which already rests on the 2023 analysis, but it tightens the case for testing every resected non-squamous tumour for EGFR mutations.

For a patient weighing the FLAURA2 regimen against osimertinib alone, the extra toxicity is front-loaded: the hardest months are the four induction cycles, and once pemetrexed stops the profile returns to that of osimertinib by itself. Kidney function deserves watching during pemetrexed maintenance.

Patients newly diagnosed with EGFR-mutated advanced lung cancer now have a first-line option that improves survival over osimertinib, particularly if they have high-risk features. The trade-off is intravenous (now subcutaneous) infusions and considerably more skin, nail and clotting toxicity, so osimertinib alone remains reasonable for those who prioritise convenience and tolerability. Both this regimen and osimertinib plus chemotherapy (FLAURA2) are approved; there is no direct comparison.

Every resected non-squamous lung cancer should be tested for EGFR mutations, because patients who carry one live longer if they take osimertinib for three years after surgery. The trial does not tell us whether adjuvant chemotherapy can be omitted, nor what happens on relapse after osimertinib, and the three-year duration was chosen empirically.

This is the separate paper behind the survival figure quoted for dacomitinib. It is a real but modest gain, and the US label notes that overall survival was not formally tested because the response rate comparison earlier in the testing order was not significant, so the P value is descriptive.

Anyone diagnosed with advanced lung cancer should have EGFR testing before treatment, because osimertinib as the first drug gives the longest disease control, protects the brain, and is well tolerated. Chemotherapy is not the first step for these patients. The remaining questions are whether to intensify upfront (adding chemotherapy or amivantamab) and how to treat resistance when it develops.

ARCHER 1050 supported dacomitinib's 2018 US first-line approval and was the first head-to-head win of a second-generation EGFR inhibitor over a first-generation one on progression-free survival. FLAURA, reported the same year, made osimertinib the usual first choice, so dacomitinib is now rarely used.