KEY TAKEAWAYS
- This Phase 2 study presented the final analysis of OS for NSCLC pts with rare EGFR mutations treated with osimertinib.
- The study’s primary endpoint was ORR by investigator assessment. Secondary endpoints were PFS, OS, DoR, and safety.
- Osimertinib exhibited favorable activity with manageable toxicity after long-term follow-up in NSCLC pts harboring uncommon EGFR mutations.
Osimertinib is an oral, third-generation, irreversible inhibitor targeting EGFR-TKI, effective against both sensitizing and T790M resistance mutations in EGFR. In a Phase II study, osimertinib displayed promising results and manageable side effects in NSCLC patients (pts) with rare EGFR mutations. This report presented the conclusive overall survival (OS) data.
Qualifying pts with metastatic or recurrent NSCLC, displaying EGFR mutations other than exon 19 deletion, L858R, and T790M, were administered a daily oral dose of 80mg osimertinib. The main objective was to evaluate the objective response rate (ORR) as assessed by investigators. Secondary objectives included measuring progression-free survival (PFS), overall survival (OS), duration of response (DoR), and safety.
A total of 37 pts participated in the study, with 36 being assessable for response. The objective response rate (ORR) was 50% (95% CI, 33%-67%). With a median follow-up duration of 61.0 months (ranging from 49.7 to 68.8 months), the median progression-free survival (PFS) was 8.0 months (95% CI, 6.8-9.2 months). Median overall survival (OS) reached 27.0 months (95% CI, 18.5-35.5 months), and the median duration of response (DoR) was 13.5 months (ranging from 1.0 to 43.0 months).
Out of the cohort, 31 pts (86%) underwent subsequent chemotherapy outside of the study, most commonly with pemetrexed and platinum. Median PFS for the second line of treatment (PFS2) was 16.0 months (95% CI, 10.1-21.9 months). Toxicity levels remained manageable.
Long-term follow-up showed the effectiveness and tolerability of osimertinib in treating NSCLC pts with rare EGFR mutations.
Source: https://cattendee.abstractsonline.com/meeting/10925/presentation/1004
Clinical Trial: https://classic.clinicaltrials.gov/ct2/show/NCT03424759
Cho, J.H., Lim, S.H., An, H.J., Kim, K.H., Park, K.U., Kang, E.J., Choi, Y.H., Ahn, M.S., Sun, J-M., Lee, S-H., Ahn, J.S., Park, K., Ahn, M-J. Final Overall Survival Analysis of Osimertinib for Patients with NSCLC Harboring Uncommon EGFR Mutations (KCSG-LU15-09).
