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
5995 - Invasive fungal diseases caused by rare pathogens in patients after hematopoietic stem cell transplantation (HSCT) & chemotherapy
Presenter: Yuliya Rogacheva
Session: Poster Display session 1
Resources:
Abstract
2961 - Safety and pharmacokinetics of novel CXCR4 antagonist YF-H-2015005 in the mobilization of hematopoietic stem cells in patients with non-Hodgkin's lymphoma
Presenter: Weiping Liu
Session: Poster Display session 1
Resources:
Abstract
5771 - Chemotherapy associated Hyponatremia in Hematological Malignancies: A retrospective study of 189 patients treated in a single medical center
Presenter: Vadim Lesan
Session: Poster Display session 1
Resources:
Abstract
1165 - Risk factors for Bacteremia-Associated Mortality of Aeromona sobria in Hematologic Malignancies
Presenter: Gabriel De la Cruz-Kú
Session: Poster Display session 1
Resources:
Abstract
5287 - Use of droplet digital polymerase chain reaction for detecting minimal residual disease: a prospective, multi-institutional study
Presenter: Hyunkyung Park
Session: Poster Display session 1
Resources:
Abstract
1886 - RUBIH2 — Use of NGS in haematological malignancies: from real world data to national recommendations, an innovative program to evaluate the impact of healthcare technology on patient care
Presenter: Severine Coquerelle
Session: Poster Display session 1
Resources:
Abstract
1940 - Outcomes of chronic myeloid leukemia with T315I mutation in the absence of targeted therapy or hematopoietic stem cell transplantation
Presenter: Nageswara Palukuri
Session: Poster Display session 1
Resources:
Abstract
1946 - Is bone marrow examination indispensible in chronic myeloid Leukemia at diagnosis ?
Presenter: Nageswara Palukuri
Session: Poster Display session 1
Resources:
Abstract
1904 - Incidence of Imatinib Resistance in Chronic Myeloid Leukemia (CML) Patients: Experience from Resource Poor Centre of Eastern India
Presenter: Debmalya Bhattacharyya
Session: Poster Display session 1
Resources:
Abstract
3245 - BCR-ABL transcript variant’s significance in chronic myeloid leukemia in chronic phase: Institutional experience from a developing country
Presenter: Siva Prasad
Session: Poster Display session 1
Resources:
Abstract