359P - Epidermal growth factor receptor (EGFR) mutation testing and immunotherapy (IO) use associated with diagnosis of non-small cell lung cancer (NSCLC) with EGFR exon 20 insertions (ex20ins) in the US

Background

As the treatment landscape for NSCLC with EGFRex20ins evolves, it is important to understand real-world diagnoses and treatment choices.

Methods

Data were collected for 75,067 patients with advanced NSCLC in the Flatiron Health electronic health record database (01/01/2011-12/31/2021). EGFR testing rates and proportion of next-generation sequencing (NGS) tests were described. For patients with EGFRex20ins(+) results in 2017-2021, IO use was reported by PD-L1 status and timing of IO initiation (pre- or post-EGFRex20ins(+) result).

Results

EGFR testing rates increased 7.5% per year on average from 4.4% in 2011 to 80.7% in 2021 (Total: 68.6%; n = 51,470). EGFRexon20 detection rate increased from 0.6% to 1.1% overall and from 4.5% to 8.2% in EGFR+ population. NGS was used in 81.0% of tests in 2021 vs <1% in 2011. From 2017-2021, 250 patients had EGFRex20ins(+) results. 169/250 (67.6%) patients were tested for PD-L1. 111/169 (65.7%) patients were PD-L1+, and 60/111 (54.1%) received IO in first-line (1L). 58/169 (34.3%) patients were PD-L1-, and 26/58 (44.8%) received IO in 1L. Most patients received IO + chemotherapy (PD-L1+: 66.7% [n=40/60 ]; PD-L1-: 96.2% [n=25/26]). 23.6% (n=59/250) and 56.4% (n=141/250) patients with EGFRex20ins(+) results started 1L pre- vs. post-EGFRex20ins(+) result. The proportion of patients receiving IO in 1L was similar in patients who started 1L therapy pre- (44.1% [n=26/59]) vs. post- (42.5% [n=60/141]) EGFRex20ins(+) results. Most received IO + chemotherapy (pre-EGFRex20ins: 80.8% [n=21/26]; post-EGFRex20ins: 73.3% [n=44/60]).

Conclusions

EGFR testing increased over time, and proportion of tests done with NGS increased from <1% to 81% during the study period; however, nearly 20% of patients still remained untested in 2021 by both NGS and PCR. Despite limited efficacy of IO in patients with EGFRex20ins mutations, a high proportion were treated with IO + chemotherapy in 1L regardless of PD-L1 status and timing of EGFRex20ins(+) result. With the recent approval of therapies targeting EGFRex20ins mutations, increased testing and awareness of treatment outcomes are needed.

Clinical trial identification

Editorial acknowledgement

Medical writing support provided by Jane Kondejewski, PhD of SNELL Medical Communication, Inc.

Legal entity responsible for the study

Takeda Development Center Americas, Inc.

Funding

Takeda Development Center Americas, Inc.

Disclosure

S.I. Ou: Financial Interests, Institutional, Other, Personal fees: Pfizer, AstraZeneca, Takeda/ARIAD, Roche/Genentech, Daiichi Sankyo, Janssen/JNJ; Financial Interests, Institutional, Stocks/Shares: Turning Point Therapeutics, Elevation Oncology; Financial Interests, Institutional, Other, Consulting fees: Takeda Development Center Americas, Inc; Financial Interests, Institutional, Funding, Research funding: Takeda Development Center Americas, Inc. M. Lin, Y. Yin, E. Curran, E. Churchill: Financial Interests, Institutional, Full or part-time Employment: Takeda Development Center Americas, Inc. Z. Piotrowska: Financial Interests, Institutional, Other, Consulting fee: Janssen, AstraZeneca, Eli Lilly, Takeda Pharmaceuticals, Daiichi Sankyo, Cullinan Oncology, C4 Therapeutics, Jazz Pharmaceuticals, Blueprint Medicines; Financial Interests, Institutional, Funding: Blueprint Medicines, Jazz Pharmaceuticals, AbbVie, Daiichi Sankyo, Cullinan Oncology, Tesaro/GSK, AstraZeneca, Spectrum, Takeda Pharmaceuticals, Novartis.