Real-World Data on Osimertinib in Chinese Patients with Pretreated, EGFR T790M Mutation Positive, Advanced Non-Small Cell Lung Cancer: A Retrospective Study

Abstract

Purpose

As a third-generation EGFR TKI has been taken orally, Osimertinib effectively inhibits mutant EGFR, including T790M EGFR resistance mutations. Here, we examined real-world efficacy and tolerability of Osimertinib among Chinese patients with advanced EGFR T790M-mutant NSCLC.

Patients and Methods

A total of 106 advanced NSCLC patients who were taking Osimertinib following disease progression after EGFR-TKIs or other treatments were retrospectively recruited in this study. The PFS and OS after Osimertinib treatment were analyzed as the primary endpoints.

Results

Osimertinib was used as a second line and ≥3rd line treatment in 22.6% and 77.4% of the patients, respectively. DCR and ORR were 93.4% and 57.5%, respectively. Median PFS was 12.4 12 (95% CI, 10.5–13.5) months. The PFS was 11 (8.0, 14.0) and 12 (10.3,13.7) months (p = 0.373), in patients with and without CNS metastasis, respectively. PFS in 2nd and ≥3rd line treatment was 11 (9.0, 13.0) and 12.4 12 (8.9, 15.1) months (p = 0.799), respectively. In patients with EGFR exon 19 deletion and exon 21 L858 mutation, the median PFS was 11 (9.2, 12.8) and 12 (9.2, 14.8) months, respectively (p = 0.833). Median PFS in the monotherapy group and combined anti-angiogenesis group was 11 (9.9,12.1) and 14 (11.2,16.8) months, respectively. Median OS after Osimertinib initiation was 27 (19.6, 34.4) months: 15 (6.9, 23.1) and 27 (22, 32) months in patients with and without CNS metastasis (p=0.027), 27 (20.3,33.7) months and (undefined) as second line or ≥3rd line of treatment (p = 0.421), respectively. In patients with exon 19 deletion, the median OS was not reached, and in patients with exon 21 L858 mutations, the median OS was 23 (19.1,29.9) months (p=0.027). Median OS in the monotherapy group was 27 (21.7,32.3) months, and in combined anti-angiogenesis group was not reached (p=0.68).

Conclusion

Osimertinib can effectively treat advanced NSCLC with T790M mutations independently of previous treatment lines.

Keywords:

• osimertinib
• EGFR-activating mutations
• T790M EGFR mutation
• tyrosine-kinase inhibitors
• non-small cell lung cancer

Ethical Statement

The study was approved by the ethics committee of Qingdao Central Hospital and affiliated Hospital of Qingdao University. This study complied with Declaration of Helsinki guidelines. Given the retrospective design of the study, some patients had passed away before the study was conducted and therefore could not give informed consent. Patient-specific information was not used in the study. Thus, the ethics committee exempted our study from requiring informed consent.

Disclosure

The authors report no conflicts of interest for this work.