What is the effect of osimertinib on objective response rate in first-line treatment?

Osimertinib combined with chemotherapy showed better post-progression survival outcomes than osimertinib alone in patients with EGFR mutated non-small cell lung cancer.

Long-term survival outcomes for patients with advanced non-small cell lung cancer following disease progression using platinum-pemetrexed chemotherapy in combination with osimertinib demonstrate clinically meaningful and statistically significant results. Based on planned post-progression analysis of results and the Phase 3FLAURA2 trial (NCT0 4035486), this combination therapy shows good efficacy in the first-line treatment of patients with advanced EGFR mutated non-small cell lung cancer.

Study results showed that compared with osimertinib alone, patients who received osimertinib plus chemotherapy had a 27% lower risk after their first subsequent treatment and a lower risk after their second progression30%（HR is 0.73, 9 The 5%confidence interval is0.56-0.94; HR is< span>0.70, 95% confidence interval is 0.52-0.93). The median time to second progression (PFS2) in the combination group was 30.6 months (95% CI, 29.0-not calculable[NC]), while the osimertinib-only group was 27.8 months (95% CI, 26.0-NC).

Benefits were also observed with the combination on other post-progression outcomes, including progression-free survival (PFS), time to second follow-up treatment (TSST), first interim overall survival (OS) and second interim OS. Among them, HR were 0.62 (95% CI, 0.49-0.79), 0.69 (95% CI, 0.51-0.93), 0.90 (95% CI, 0.65-1.24) and 0.75 (95% CI, 0.57-0.75).

Results from the second interim OS analysis of the FLAURA2 trial showed that at a median follow-up of 31.7 months (range 0.1-43.3), the median overall survival in the combination arm had not been reached (95%). CI, 38.0-NC). The overall maturity of these data was 41% after a median follow-up of 30.5 months (range: 0.1-43.0; P= .0280). The probability of overall survival was initially higher with monotherapy within 12 months of treatment initiation, but by 24 and 36 months, the overall survival benefit was greater with the combination group.