Abstract 5733
Background
Osimertinib is an oral, potent, irreversible EGFR tyrosine kinase inhibitor (TKI) selective for sensitizing EGFR and EGFRT790M mutations and approved for the first-line treatment of patients with sensitizing EGFR-mutant NSCLC. EGFR exon 20 insertion mutations account for up to 4% of all EGFR mutations and are generally resistant to EGFR TKIs. Although osimertinib is active against in vitro models of EGFR exon 20 insertion mutation, its efficacy has not been prospectively studied. This phase II study has been performed to evaluate the efficacy of osimertinib in NSCLC patients with EGFR exon 20 insertion mutation who failed to standard chemotherapy (ClinicalTrials.gov, NCT03414814).
Methods
Patients received osimertinib 80mg orally once daily until disease progression, unacceptable toxicities, withdrawal, or no clinical benefits. Primary end point was investigator-assessed, confirmed objective response rate (ORR) as defined by RECIST version 1.1. Secondary end points were safety profiles, progression-free survival (PFS), overall survival (OS), and duration of response.
Results
Between Jan 2018 and Feb 2019, 15 patients received osimertinib as second-line (20%, n = 3) and ≥ third-line (n = 12) at stage 1 according to Simon’s minimax two-stage design (P0=0.10, P1=0.30; α = 0.05, β = 0.20). Median age was 61 years and female were 66.7%. ORR was 0% with mostly disease stabilization (stable disease, 46.7%, n = 7). Three patients who had EGFR exon 20 insertions at M766, A767, and unknown sites were still receiving osimertinib at the cut-off date (disease stabilization, 12, 7, and 7 months, respectively). Median PFS and OS were 3.5 months (95% CI 1.6-not reached) and not reached (1-year OS rate, 56.3%), respectively. Disease control rate at 6 months was 31.1%. The most frequently observed adverse events (AEs, all grades, %) were nausea (20%, n = 3), vomiting (20%, n = 3), anemia (13.3%, n = 2), and fever (13.3%, n = 2).
Conclusions
Osimertinib is well tolerated, but has limited clinical activity in NSCLC patients with EGFR exon 20 insertion mutation who failed to standard chemotherapy.
Clinical trial identification
NCT03414814.
Editorial acknowledgement
Legal entity responsible for the study
Tae Min Kim.
Funding
AstraZeneca.
Disclosure
T.M. Kim: Advisory / Consultancy, without any compensation: AstraZeneca; Advisory / Consultancy, without any compensation: Novartis; Advisory / Consultancy, without any compensation: Sanofi; Advisory / Consultancy, without any compensation: Bayer; Research grant / Funding (self), outside this work: AstraZeneca; Advisory / Consultancy, without any compensation: Takeda. B. Keam: Research grant / Funding (self), outside this work: AstraZeneca; Research grant / Funding (self), outside this work: MSD; Research grant / Funding (self), outside this work: ONO; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: MSD; Advisory / Consultancy: Genexine. D. Kim: Advisory / Consultancy, without any compensation: AstraZeneca; Advisory / Consultancy, without any compensation: Novartis; Advisory / Consultancy, without any compensation: Takeda. All other authors have declared no conflicts of interest. Linguistic correction
Resources from the same session
4321 - Health-related quality of life of advanced melanoma survivors treated with CTLA-4 immune checkpoint inhibition: a matched cohort study
Presenter: Annelies Boekhout
Session: Poster Display session 1
Resources:
Abstract
779 - Capecitabine vs Cisplatin along with concurrent radiotherapy in the treatment of inoperable lower esophageal cancers focusing on TWISTT score and QOL
Presenter: Goutham Anugu
Session: Poster Display session 1
Resources:
Abstract
5914 - Cancer, Mental Health and End Life Simulation (CAMhELS): A novel effectiveness evaluation.
Presenter: Asanga Fernando
Session: Poster Display session 1
Resources:
Abstract
2597 - Cancer patients’ expectations and understanding about their disease
Presenter: Mónica Pinho
Session: Poster Display session 1
Resources:
Abstract
5187 - Impact of patients’ death on oncologists and coping strategies: An online survey
Presenter: Soumaya Labidi
Session: Poster Display session 1
Resources:
Abstract
4579 - Clinical benefit from late lines of therapy offered to patients treated in a tertiary referral centre
Presenter: Andrea Sbrana
Session: Poster Display session 1
Resources:
Abstract
5058 - Preparedness for caregiving in caregivers of cancer patients
Presenter: Hatice Yakar
Session: Poster Display session 1
Resources:
Abstract
5917 - Oncologic Emergency Medicine in the real world: A survey and proposal for improvement
Presenter: Carintia Dorta Pérez
Session: Poster Display session 1
Resources:
Abstract
4077 - The Reality of Critical Cancer Patients in a Polyvalent Intensive Care Unit
Presenter: Tiago Filipe Da Cruz Tomas
Session: Poster Display session 1
Resources:
Abstract
1728 - A phase III trial evaluating olanzapine 5 mg for the prevention of chemotherapy-induced nausea and vomiting in patients receiving cisplatin: J-FORCE Study
Presenter: Hironobu Hashimoto
Session: Poster Display session 1
Resources:
Abstract