On 17th May 2023, AstraZeneca announced positive results from the phase 3 FLAURA2 trial, evaluating the efficacy and safety of first-line treatment with osimertinib plus chemotherapy for patients with locally advanced or metastatic epidermal growth factor receptor-mutated (EGFRm) non-small cell lung cancer (NSCLC). Compared to osimertinib alone, this combination significantly prolonged the progression-free survival of these patients without the emergence of unexpected safety concerns. By extending the duration of time patients can live without disease progression, osimertinib offers a promising prospect in improving clinical outcomes for this patient population.
Lung cancer remains to be the leading cause of cancer-related deaths for both men and women, surpassing breast, prostate, and colorectal cancers combined. Every year, around 2.2 million people worldwide receive a lung cancer diagnosis, with about 80-85% of patients being diagnosed with non-small cell lung cancer (NSCLC). Among NSCLC patients, approximately 10-15% in the US and Europe, and 30-40% in Asia, harbour a mutation in the EGFR gene (EGFRm). These patients are particularly sensitive to treatment with EGFR-tyrosine kinase inhibitors (TKIs), which effectively block the signalling pathways responsible for tumour cells growth.
Tagrisso® (osimertinib), a third-generation, irreversible EGFR-TKI that inhibits both EGFR-sensitising and EGFR T790M-resistance mutations, is the current standard first line treatment for patients with EFGRm advanced NSCLC. To further enhance treatment outcomes, the phase 3 FLAURA2 trial assessed the efficacy and safety of combining osimertinib with chemotherapy in this setting.
The global phase 3 FLAURA2 trial enrolled 586 patients with locally advanced (stage IIIB-IIIC) or metastatic (stage IV) EGFRm NSCLC. Patients were randomly assigned to receive osimertinib 80mg once daily oral tablets alone or in combination with chemotherapy plus cisplatin or carboplatin every three weeks for four cycles, followed by osimertinib with pemetrexed maintenance every three weeks. The primary endpoints of the study consisted of progression-free survival (PFS), with overall survival (OS) as a key secondary objective.
The results showed a significant and clinically meaningful improvement in PFS with osimertinib plus chemotherapy compared to osimertinib alone. Safety results and discontinuation rates due to adverse events were consistent with the established profiles of each medicine. At the time of this analysis, OS data were immature and will be formally assessed at a subsequent analysis.
The promising results from the FLAURA2 trial underscore the potential of osimertinib as a treatment option for EGFRm NSCLC patients in the first-line setting. This exciting news builds upon the positive findings from previous trials, further establishing osimertinib as a valuable therapeutic choice for individuals with EGFR-mutated lung cancer.