Trial Design & Population
- Participants: 557 treatment-naïve patients with locally advanced or metastatic NSCLC harboring EGFR exon 19 deletion or L858R mutations.
- Randomization:
- Combination arm: osimertinib (80 mg daily) + platinum-pemetrexed chemotherapy (4 cycles, followed by maintenance pemetrexed + osimertinib)
- Control arm: osimertinib monotherapy (80 mg daily)
- Key eligibility: ECOG performance status 0–1; stable CNS metastases permitted; stratified by race, mutation type, and testing method.
Primary Outcomes
Progression-Free Survival (PFS)
- Median PFS:
- Combination: ~25.5 months
- Monotherapy: ~16.7 months
- Hazard Ratio (HR): ~0.62 (38% reduction in risk of progression/death; p < 0.001)
- Consistent benefit across subgroups, including age, sex, race, mutation subtype, smoking history, and presence of baseline CNS metastases
CNS Efficacy
- In patients with baseline CNS metastases:
- Median CNS PFS: ~24.9 months (combination) vs ~13.8 months (monotherapy)
- CNS response rates were markedly improved—up to 48% complete responses in CNS lesions vs 16% with osimertinib alone
Additional Outcomes
Overall Survival (OS)
- Interim OS data were immature (~27% maturity):
- HR approx 0.90 (95% CI, 0.65–1.24; not statistically significant)
- Median OS not yet reached in combination arm; ~36.7 months in monotherapy arm
- Final OS analysis later confirmed a statistically significant survival benefit for combination therapy over osimertinib alone
Safety Profile
- Higher rates of grade ≥3 adverse events in the combination arm:
- Combination: ~64%, mainly hematologic (anemia, neutropenia, thrombocytopenia)
- Monotherapy: ~27%
- Discontinuation of osimertinib due to AEs:
- Combination: ~11%
- Monotherapy: ~6%
- No new safety concerns emerged; adverse effects aligned with known profiles of the individual treatments
Clinical Takeaway
- FLAURA-2 shows that adding pemetrexed-based chemotherapy to osimertinib significantly extends PFS—by approximately 8–9 months—versus osimertinib alone in first-line EGFRm NSCLC.
- The combination notably enhances control of CNS disease and shows a positive trend toward improved OS, with the latest analysis confirming a meaningful survival benefit.
- Elevated but manageable toxicity underscores the importance of patient selection and monitoring.
- These findings support considering osimertinib plus chemotherapy as a new standard of care in appropriate first-line settings.