Prior Epidermal Growth Factor Receptor Research Articles

Lazertinib in EGFR-Variant Non–Small Cell Lung Cancer With CNS Failure to Prior EGFR Tyrosine Kinase Inhibitors

EGFR-variant non-small cell lung cancer (NSCLC) is associated with a high rate of central nervous system (CNS) metastases, even with treatment with first-generation or second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). To investigate CNS activity with lazertinib, a third-generation EGFR TKI. This multicenter single-arm, phase 2 nonrandomized controlled trial was conducted in South Korea and included patients with EGFR-variant NSCLC who had asymptomatic or mildly symptomatic brain metastases after unsuccessful treatment with first-generation or second-generation EGFR TKIs. Data were collected from June 2021 to April 2022, with a data cutoff date of December 15, 2022. Lazertinib, 240 mg, once daily. The primary end point was intracranial objective response rate (iORR) in the evaluable population according to the Response Evaluation Criteria in Solid Tumours version 1.1 assessed by the investigators. Secondary end points included intracranial progression-free survival (iPFS) and iORR in patients with T790M-negative disease and isolated CNS progression as well as overall ORR, duration of response, intracranial duration of response, disease control rate, overall survival, cerebrospinal fluid penetration of lazertinib, and safety. Among 40 included patients, 25 (63%) were women, and the median (range) age was 63 (29-85) years. A total of 38 patients were evaluable for tumor response, including 12 patients with leptomeningeal metastases. At data cutoff, the median (range) follow-up was 13.6 (2.9-17.7) months. The iORR for the evaluable population was 55% (21 of 38; 95% CI, 38.3-71.4); for patients with T790M-positive disease, 80% (4 of 5; 95% CI, 28.4-99.5); for patients with T790M-negative disease, 43% (9 of 21; 95% CI, 21.8-66.0); and for patients with T790M-unknown disease, 67% (8 of 12; 95% CI, 34.9-90.1). The median iPFS was 15.8 months (95% CI, 15.2-not reached) for the evaluable population, 15.2 months (95% CI, 4.2-not reached) for the T790M-positive subgroup, 15.4 months (95% CI, 7.9-not reached) for the T790M-negative subgroup, and 18.0 months (95% CI, 3.9-not reached) for the T790M-unknown subgroup. The cerebrospinal fluid penetration rate of lazertinib was 46.2% (95% CI, 10.0-49.6), providing further support for its mechanism of intracranial response. Most adverse events were grade 1 or 2. In this study, lazertinib had substantial CNS activity, regardless of T790M status, against the progression of intracranial metastases with or without leptomeningeal metastases after unsuccessful treatment with first-generation or second-generation EGFR TKIs in patients with metastatic EGFR-variant NSCLC. These results suggest that using lazertinib instead of brain local treatment could be a potential strategy in patients with EGFR-variant NSCLC whose CNS metastases progressed after prior EGFR TKI treatment. ClinicalTrials.gov Identifier: NCT05326425.

PD-L1 expression from surgically resected lung tumors predictive of early progression in patients previously treated with targeted therapy for initially unresectable non-small cell lung cancer.

Recent evidences showed that resection of lung tumor post-targeted therapy has shown progression-free survival (PFS) benefits in initially unresectable patients. The aim of this study is to evaluate pathologic findings of resected lung tumor samples in patients who have undergone prior epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI) treatment, and also to assess the prognostic factors related to outcomes after resection. The deidentified data of non-small cell lung cancer (NSCLC) patients admitted to seven university hospitals affiliated with the Catholic University of Korea were obtained from the Clinical Data Warehouse (CDW) database. Among screened patients, 40 individuals who had previously undergone targeted therapies and later received surgical resection of a primary lung tumor were evaluated for the study. All 40 patients were diagnosed with adenocarcinoma. Of these, 36 with EGFR mutations received prior EGFR TKI treatment. Only one postoperative complication, atrial fibrillation, was observed. At the time of resection, 19 patients showed primary lung tumor size regressing or unchanged, while 21 patients showed primary lung tumor regrowth or new lesions being developed before the resection. The group with no programmed death-ligand 1 (PD-L1) expression from resected samples showed significantly better post-resection PFS when compared to the other group (P=0.01). In the Model II multivariate analysis for post-resection PFS, PD-L1 detection from the resected sample was significantly associated with PFS [P=0.03; hazard ratio (HR) =5.465; 95% confidence interval (CI): 1.200-24.885]. Furthermore, an increase in PD-L1 expression compared to the baseline value was associated with an increasing lung tumor burden at the time of resection (P=0.03). Resected specimen following targeted therapy can provide valuable clinical information that can be used to predict the prognosis of patients with initially unresectable NSCLC.

Phase II Efficacy and Safety of 80 mg Osimertinib in Patients With Leptomeningeal Metastases Associated With Epidermal Growth Factor Receptor Mutation-Positive Non-Small Cell Lung Cancer (BLOSSOM).

Leptomeningeal metastases (LMs) exhibit a high incidence in patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) post-treatment with first- or second-generation EGFR tyrosine kinase inhibitors (TKIs). This investigation evaluates the efficacy, safety, and pharmacokinetics of 80 mg once daily osimertinib in patients with LMs resistant to prior first- or second-generation EGFR TKIs. In this phase II multicenter, open-label, single-arm study, 80 mg osimertinib was administered to patients with EGFR-mutated NSCLC who had developed LMs subsequent to treatment with prior EGFR TKIs. The primary end point was overall survival (OS), assessed alongside objective response rate by the blinded independent central review (BICR) and a pharmacokinetic analysis of plasma and cerebrospinal fluid (CSF) on the first day of cycles 3 and 6. A total of 73 patients diagnosed with LM were treated with osimertinib, including 64 patients evaluable for the LM efficacy set-T790M negative (n = 62) and T790M positive (n = 2). The median OS in the full-analysis set was 15.6 months (95% CI, 11.5 to 20.2). The objective response rate for LM was 51.6%, including a 15.6% complete response, and the disease control rate was 81.3% by BICR in the LM efficacy evaluable set. The median LM progression-free survival by BICR was 11.2 months (95% CI, 7.7 to 15.3), the duration of response was 12.6 months (95% CI, 7.6 to 17.7), and OS was 15.0 months (95% CI, 11.3 to 18.7). Pharmacokinetic analysis showed that the CSF to free plasma osimertinib ratio was 22%. Most safety profiles were grade 1 and 2. The study demonstrates significant intracranial efficacy and survival benefits of 80 mg once daily osimertinib in NSCLC patients with LMs. The data support considering daily 80 mg of osimertinib as a treatment option for EGFR-mutated NSCLC patients with LMs, irrespective of T790M mutation status.

FURTHER: A global study to evaluate furmonertinib in patients with EGFR mutant NSCLC including uncommon EGFR mutations (FURMO-002).

TPS8666 Background: Furmonertinib (AST2818) is an oral, highly brain-penetrant, and broadly active mutation-selective epidermal growth factor receptor ( EGFR) inhibitor engineered for broad activity and selectivity across EGFRmutations (mts) (1). Furmonertinib is approved in China for first-line advanced NSCLC with EGFR Ex19del or L858R mts based on the progression-free survival benefit observed in the Phase 3 study versus gefitinib (FURLONG). Furmonertinib has also demonstrated promising interim efficacy and safety in patients (pts) with NSCLC harboring EGFR exon 20 insertion (ex20ins) mts with a confirmed overall response rate (ORR) of 78.6% (n=28) by blinded independent central review (BICR) and a preliminary median duration of response (DoR) of 15.2 months in the front-line setting (FAVOUR study; see Han et al., WCLC 2023). Furmonertinib recently obtained FDA Breakthrough Therapy Designation for the treatment of pts with advanced NSCLC with EGFR ex20ins mts. P-loop and αC-helix Compressing (PACC) mts represent another subset of uncommon EGFR mts (2) that are similar to ex20ins mts in narrowing the drug-binding pocket; including G719X, S768I, E709X, L747X, V774M. Preclinical data indicating that furmonertinib is potent in models harboring EGFR PACC mts Developing efficacious, well-tolerated, and CNS-penetrant medicines for NSCLC pts with EGFR ex20ins mts and PACC mts remains an unmet need. Methods: FURTHER (FURMO-002) is the first global trial evaluating furmonertinib in NSCLC pts with EGFR and HER2 mts in North America, Europe, and the Asia-Pacific. FURTHER is a phase 1b, open-label, multicenter study in which pts will be treated orally with furmonertinib daily. For Stage 1 dose-escalation, the primary endpoint is incidence and severity of adverse events, including dose limiting toxicities and has been completed. For Stage 2 dose expansion, approximately 120 pts will be enrolled across 4 expansion cohorts. Stage 2 Cohorts 1-3 dose expansion cohorts will enroll pts with previously treated, locally advanced or metastatic NSCLC pts with either EGFR ex20ins mts, HER2 ex20ins mts, or EGFR activating mts, respectively. Cohorts 1-3 allow enrollment of pts with prior EGFR or HER2-directed therapy. Stage 2 Cohort 4 will enroll EGFR TKI-naïve NSCLC pts with EGFR PACC mts. Key inclusion criteria include documented EGFR or HER2 mts by local testing and measurable disease per RECIST v1.1. Stage 2 primary endpoint is ORR using RECIST v1.1. Key secondary endpoints include progression-free survival and overall survival. Stage 2 enrollment is ongoing. 1. Musib et al., NACLC 2022. 2. Robichaux et al., 2021. Clinical trial information: NCT05364073 .

Phase 1 study of BDTX-1535, an oral 4th generation covalent EGFR inhibitor, in patients with recurrent glioblastoma: Preliminary dose escalation results.

2068 Background: Epidermal growth factor receptor ( EGFR) gene is the most frequently altered oncogenic driver in glioblastoma (GBM). In-frame deletion alterations (e.g., EGFRvIII) and missense mutations co-occur in the setting of EGFR gene amplification and are characterized as a hallmark of disease pathogenesis in GBM. BDTX-1535 is an oral, highly potent, brain penetrant, selective, irreversible 4th generation tyrosine kinase inhibitor that targets EGFR alterations in GBM and NSCLC. Preliminary results of the Phase 1 dose escalation study (NCT05256290) of patients with recurrent GBM (rGBM) are presented here. Methods: BDTX-1535-101 is a first-in-human study that enrolled patients with either rGBM harboring EGFR alterations following standard of care or patients with locally advanced or metastatic EGFR mutated NSCLC that progressed on prior EGFR TKIs. Using an adaptive Bayesian optimal interval design in the Phase 1 part, patients were enrolled at increasing dose cohorts and were treated daily for 21-day cycles until treatment discontinuation. The primary objective was to determine the BDTX-1535 recommended Phase 2 dose based on the overall safety, PK, pharmacodynamics, and preliminary antitumor activity. Results: Twenty-seven patients with rGBM were enrolled in the Phase 1 cohort that consisted of 54 patients in total including 27 patients with NSCLC. Patients were treated across seven dose levels (15mg – 400mg QD). The mean age of patients with rGBM was 58.7 years (range 41-85) with 96% of patients with previous temozolomide (TMZ) treatment and a median of 2 lines of prior therapy (range 1-4). The most common all-grade treatment-related AEs across all cohorts were rash (78%), diarrhea (41%), fatigue (15%), stomatitis (11%), decreased appetite (11%), nausea (11%) and paronychia (11%). Gr 3 TRAEs ≥ 10% included rash (19%) reported at 300 or 400 mg QD doses. Plasma exposure of BDTX-1535 increased dose proportionally and had a half-life of ~15h, supporting once daily dosing. The maximum tolerated dose (MTD) is 300 mg QD. Among 19 evaluable patients for response based on RANO criteria, 1 confirmed partial response was observed and 8 patients achieved stable disease. Five patients remained on BDTX-1535 with stable disease for an extended period (>5 months) who previously performed poorly on TMZ with short treatment duration, and 1 patient continues on BDTX-1535 after 16 months of treatment. Conclusions: BDTX-1535 was well-tolerated up to 300mg daily, which is the MTD, and promising preliminary clinical activity was observed in patients with rGBM after relapse on standard of care treatment. Given the inability to reconfirm EGFR status at the time of treatment with BDTX-1535 in this Phase 1 trial, further exploration of BDTX-1535 in a “window of opportunity” study is ongoing (NCT06072586). Clinical trial information: NCT05256290 .

Abstract CT152: FURTHER: A global study to evaluate furmonertinib in patients with EGFR mutant NSCLC including uncommon EGFR mutations

Abstract Background: Furmonertinib (AST2818) is an oral, highly brain-penetrant, and broadly active mutation-selective epidermal growth factor receptor (EGFR) inhibitor engineered for broad activity and selectivity across EGFR mutations (mts) (Musib et al., NACLC 2022). Furmonertinib is approved in China for first-line advanced NSCLC with EGFR Ex19del or L858R mts based on the positive Phase 3 study (FURLONG) versus gefitinib. Furmonertinib has also demonstrated promising interim efficacy and safety in patients (pts) with NSCLC with EGFR exon 20 insertion (ex20ins) mts with a confirmed overall response rate (ORR) of 78.6% (n=28) by blinded independent central review (BICR) with a preliminary median duration of response (DoR) of 15.2 months in the front-line setting (FAVOUR study; see Han et al., WCLC 2023). Furmonertinib recently obtained FDA Breakthrough Therapy Designation for the treatment of pts with advanced NSCLC with EGFR ex20ins mts. P-loop and αC-helix Compressing (PACC) mts represent another subset of uncommon EGFR mts (Robichaux et al., 2021) that are similar to ex20ins mts in narrowing the drug-binding pocket; including G719X, S768I, E709X, L747X, V774M. Preclinical data indicating that furmonertinib is potent in models harboring EGFR PACC mts will be presented at this meeting (Nilsson et al., Abstract #4174). Developing efficacious, well-tolerated, and CNS-penetrant medicines for NSCLC pts with EGFR ex20ins mts and PACC mts remains an unmet need. Methods: FURTHER (FURMO-002) is the first global trial evaluating furmonertinib in NSCLC pts with EGFR and HER2 mts in North America, Europe, and the Asia-Pacific. FURTHER is a phase 1b, open-label, multicenter study in which pts will be treated orally with furmonertinib daily. For Stage 1 dose-escalation, the primary endpoint is incidence and severity of adverse events, including dose limiting toxicities and has been completed. For Stage 2 dose expansion, approximately 120 pts will be enrolled across 4 expansion cohorts. Stage 2 Cohorts 1-3 dose expansion cohorts will enroll pts with previously treated, locally advanced or metastatic NSCLC pts with either EGFR ex20ins mts, HER2 ex20ins mts, or EGFR activating mts, respectively. Cohorts 1-3 allow enrollment of pts with prior EGFR or HER2-directed therapy. Stage 2 Cohort 4 will enroll EGFR TKI-naïve NSCLC pts with EGFR PACC mts. Key inclusion criteria include documented EGFR or HER2 mts by local testing and measurable disease per RECIST v1.1. Stage 2 primary endpoint is ORR using RECIST v1.1. Key secondary endpoints include progression-free survival and overall survival. Stage 2 enrollment is ongoing. Clinical trial information: NCT05364073. Citation Format: Xiuning Le, Alexander Spira, Shirish Gadgeel, Yan Yu, Yanqiu Zhao, Ying Cheng, Jonathan Riess, Oscar Juan-Vidal, Bo Gao, Kiyotaka Yoh, Martin Forster, Satoru Kitazono, Hidetoshi Hayashi, David Planchard, Yong Jiang, Jack Huang, Nichole Baio, Marcin Kowanetz, Shirley Wang, William Leung, Jerry Y. Hsu, Jie Wang. FURTHER: A global study to evaluate furmonertinib in patients with EGFR mutant NSCLC including uncommon EGFR mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT152.

Abstract C036: A Phase 1 Study to assess BDTX-1535, an oral EGFR inhibitor, in patients with Glioblastoma or Non-Small Cell Lung Cancer

Abstract Background: Epidermal growth factor receptor (EGFR) is a potent oncogene commonly altered in non-small cell lung cancer (NSCLC) and glioblastoma (rGBM). For NSCLC, EGFR tyrosine kinase activity can be driven by classical driver, intrinsic driver, and acquired resistance mutations. BDTX-1535 is an orally available, highly potent, brain penetrant, selective, irreversible small molecule tyrosine kinase inhibitor that targets all 3 classes of EGFR mutations. Preclinical data demonstrated the ability of BDTX-1535 to cross the blood-brain barrier and produce sustained inhibition of EGFR signaling. Methods: BDTX-1535-101 (NCT05256290) is a Phase 1, open-label, multicenter study to assess the safety, tolerability, pharmacokinetics (PK), central nervous system (CNS) activity, and preliminary antitumor activity of BDTX-1535 in locally advanced or metastatic NSCLC with or without CNS disease or recurrent GBM (rGBM). The primary objective is to determine the BDTX-1535 recommended Phase 2 dose (RP2D) based on the overall safety, PK, pharmacodynamic, and preliminary antitumor activity. The monotherapy dose escalation portion evaluates BDTX-1535 in patients with locally advanced/metastatic NSCLC harboring intrinsic driver EGFR mutations following standard of care or with acquired resistance EGFR mutations following a 3rd generation EGFR inhibitor in the 1st line setting, in addition to patients with rGBM expressing EGFR alterations who previously received available standard therapy of surgical resection followed by chemoradiotherapy and/or temozolomide (TMZ). A capsule-to-tablet bridging cohort and a food effect cohort will also be assessed. Following the establishment of a preliminary recommended Phase 2 dose (RP2D), the disease-specific expansion portion of the study will further evaluate the safety, tolerability, and preliminary antitumor effect of BDTX-1535. Cohorts include the following:1) advanced/metastatic NSCLC with intrinsic resistance EGFR mutations following up to 2 lines of therapy, one of which must be an EGFR inhibitor treatment, 2) advanced/metastatic NSCLC with acquired resistance EGFR mutation following a 3rd generation EGFR inhibitor in the first line setting, 3) rGBM with confirmed EGFR alterations with or without amplifications. NSCLC patients may enroll with or without CNS metastases and must not be known to express excluded resistance mutations such as EGFR T790M. BDTX-1535 will also be studied in combination with TMZ to assess safety, tolerability, and a recommended combination dose for the treatment of patients with newly diagnosed GBM harboring EGFR alterations. Enrollment was initiated in 2022 and dose escalation is almost complete. Initiation of the dose expansion cohorts of NSCLC patients with EGFR acquired resistance and intrinsic driver mutations after progression on prior EGFR inhibitor is planned for the second half of 2023. For additional information, please contact ClinicalTrials@bdtx.com. Citation Format: Helena Yu, Melissa Johnson, Jason T Henry, Alex Spira, Ji-Youn Han, Minal Barve, James Battiste, Iyad Alnahhas, DoHyun Nam, Jeffrey Edenfield, Balazs Halmos, Shinkyo Yoon, Tae Min Kim, Sudharshan Eathiraj, Julio Hajdenberg, Sergey Yurasov, Manmeet Ahluwalia, Patrick Wen. A Phase 1 Study to assess BDTX-1535, an oral EGFR inhibitor, in patients with Glioblastoma or Non-Small Cell Lung Cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr C036.

A Phase II Study of Osimertinib in Patients with Advanced-Stage Non-Small Cell Lung Cancer following Prior Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor (EGFR TKI) Therapy with EGFR and T790M Mutations Detected in Plasma Circulating Tumour DNA (PLASMA Study).

Epidermal growth factor receptor (EGFR) T790M mutations drive resistance in 50% of patients with advanced non-small cell lung cancer (NSCLC) who progress on first/second generation (1G/2G) EGFR tyrosine kinase inhibitors (TKIs) and are sensitive to Osimertinib. Tissue sampling is the gold-standard modality of T790M testing, but it is invasive. We evaluated the efficacy of Osimertinib in patients with EGFR mutant NSCLC and T790M in circulating tumour DNA (ctDNA). PLASMA is a prospective, open-label, multicentre single-arm Phase II study. Patients with advanced NSCLC harbouring sensitizing EGFR and T790M mutations in plasma at progression from ≥one 1G/2G TKI were treated with 80 mg of Osimertinib daily until progression. The primary endpoint was the objective response rate (ORR); the secondary endpoints included progression-free survival (PFS), overall survival (OS), disease control rate (DCR) and toxicities. Plasma next-generation sequencing was performed to determine Osimertinib resistance mechanisms and assess serial ctDNA. A total of 110 patients from eight centres in five countries were enrolled from 2017 to 2019. The median follow-up duration was 2.64 (IQR 2.44-3.12) years. The ORR was 50.9% (95% CI 41.2-60.6) and the DCR was 84.5% (95% CI 76.4-90.7). Median PFS was 7.4 (95% CI 6.0-9.3) months; median OS was 1.63 (95% CI 1.35-2.16) years. Of all of the patients, 76% had treatment-related adverse events (TRAEs), most commonly paronychia (22.7%); 11% experienced ≥ Grade 3 TRAEs. The ctDNA baseline load and dynamics were prognostic. Osimertinib is active in NSCLC harbouring sensitizing EGFR and T790M mutations in ctDNA testing post 1G/2G TKIs.

Tislelizumab plus chemotherapy for patients with EGFR-mutated non-squamous non-small cell lung cancer who progressed on EGFR tyrosine kinase inhibitor therapy

BackgroundTreatment options are limited for epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) after treatment failure with EGFR tyrosine kinase inhibitors (TKIs). This multicenter open-label, phase II study...

EP08.02-139 A Phase 2 Study of Befotertinib in Patients with EGFR T790M Mutated NSCLC after Prior EGFR TKIs

Befotertinib (D-0316) is a novel, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). This study aimed to evaluate the efficacy and safety of befotertinib in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) that had EGFR T790M mutation after prior first- or second-generation EGFR TKIs.

Efficacy of dacomitinib in patients with EGFR-mutated NSCLC and brain metastases.

BackgroundDacomitinib is a second‐generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) which is superior to first‐generation EGFR TKI in ARCHER 1050. However, the activity of dacomitinib in the central nervous system (CNS) is not known as ARCHER 1050 did not include patients with baseline brain metastases. This study aimed to describe dacomitinib's activity in the CNS in a real‐world setting.Patients and MethodsThirty‐two patients who were receiving dacomitinib for advanced non‐small‐cell lung cancer (NSCLC) with EGFR mutations and brain metastasis were included in this study. Patients who received prior EGFR TKIs were excluded from this trial. Case report forms were collected to determine treatment outcomes.ResultsAmong 32 patients with EGFR‐mutated NSCLC and brain disease, eight were included in the CNS evaluable for response group. The intracranial objective response rate (iORR) was 87.5% (95% confidence interval [CI] 47.3–99.7%) and the intracranial disease control rate (iDCR) was 100% (95% CI 63.1–100%). In 30 evaluable patients with measurable or nonmeasurable brain lesions, the iORR was 66.7% (95% CI 47.2–82.7%) and the iDCR was 100% (95% CI 88.4–100%). Median intracranial duration of response (iDoR) and intracranial progression‐free survival (iPFS) were not reached, with a one‐year iDoR rate of 72.2% (95% CI 48.7–95.7%) and a 1‐year iPFS rate of 71.2% (95% CI 51.0–91.4%), respectively. The majority of patients experienced low‐grade (G1/2) toxicities, which are reversible.ConclusionThis study suggests that dacomitinib demonstrated CNS efficacy in patients with EGFR TKI‐naïve EGFR‐mutated NSCLC in the real‐world setting. The safety profile was tolerable and manageable.

1365TiP A phase I/II, open-label study of BBT-176, a triple mutation targeting EGFR TKI, in patients with NSCLC who progressed after prior EGFR TKI therapy

First- and third-generation epidermal growth factor receptor (EGFR) inhibitors such as gefitinib and osimertinib, respectively, have improved survival outcomes for patients with advanced EGFR-mutant NSCLC. However, acquired resistance invariably emerges, leading to disease progression. The predominant mechanism of acquired resistance is a tertiary mutation at C797 position of EGFR gene added to T790M mutation which is the most well-known resistance mechanism to 1st generation EGFR inhibitors. BBT-176 specifically and non-covalently inhibits triple-mutant EGFR (exon19del/T790M/C797S and L858R/T790M/C797S).

Efficacy and dose of afatinib in patients with non-small cell lung cancer after failure of prior gefitinib or erlotinib treatment.

BackgroundWe report a subgroup analysis of afatinib with respect to its efficacy, safety, and the long‐term survival of patients in a Named Patient Use program at a single institution.MethodsWe analyzed 60 patients with stage IV non‐small cell lung cancer (NSCLC) who had been treated with ≥1 line of platinum‐based chemotherapy and had activating epidermal growth factor receptor (EGFR) mutations or disease control for ≥6 months with prior EGFR inhibitors. Afatinib was started on a daily dose of 50 mg, which was decreased according to the adverse events and tolerability.ResultsA total of 13 patients achieved partial remission, whereas 33, 12, and two showed stable disease, had progression, and were not evaluable, respectively, resulting in an objective response rate and disease control rate of 21.7% and 76.7%, respectively. The median progression‐free survival (PFS) was 5.4 (95% confidence interval [CI]: 4.0–7.7) months and median overall survival (OS) was 10.1 (8.5–13.6) months. Toxicities leading to drug discontinuation were experienced by four patients (6.7%). Grade 3 diarrhea occurred in 10 patients (16.7%), and afatinib dose reductions were required in 35 patients. The PFS and OS were significantly longer for patients whose dose was reduced to 40 or 30 mg than for those without dose reduction (7.0 vs 3.1 months and 13.5 vs 8.1 months, respectively, p < 0.05).ConclusionsThe efficacy of afatinib was similar to that identified in the global data without unexpected adverse events. Survival analyses support the currently approved dose of afatinib as first‐line treatment for NSCLC.

P76.74 PAPILLON: Randomized Phase 3 Study of Amivantamab Plus Chemotherapy vs Chemotherapy Alone in EGFR Exon20ins NSCLC

Epidermal growth factor receptor (EGFR) Exon 20 insertions (Exon20ins) account for approximately 10% of all EGFR-mutant non-small cell lung cancers (NSCLCs). Currently approved EGFR tyrosine kinase inhibitors (TKIs) are considered ineffective against Exon20ins NSCLC, and the standard of care for patients with Exon20ins disease remains platinum-based doublet chemotherapy. Amivantamab (JNJ-61186372) is an EGFR-MET bispecific antibody with immune-cell directing activity that targets activating and resistance EGFR mutations and MET mutations and amplifications. Amivantamab has shown monotherapy activity, with a tolerable safety profile, in the ongoing phase 1 CHRYSALIS study (NCT02609776) in patients with diverse EGFR-mutant NSCLC and has received FDA Breakthrough Therapy Designation for the treatment of patients with EGFR Exon20ins NSCLC, after prior platinum-based chemotherapy (Haura JCO 37;no.15_suppl:9009; Park JTO 38;no. 15_suppl:9512). The primary objective of this phase 3 randomized, open-label study is to compare the efficacy of amivantamab in combination with chemotherapy (amivantamab/carboplatin/pemetrexed) versus carboplatin/pemetrexed alone as a first-line treatment for patients with EGFR Exon20ins disease. The multicenter, global PAPILLON study is planned to open in 200 sites in 25 countries and enroll patients with EGFR Exon20ins-mutant NSCLC who are treatment-naive for metastatic disease, although limited prior EGFR TKI exposure may be allowed. Eligible patients also have measurable disease according to RECIST v1.1, Eastern Cooperative Oncology Group performance status (ECOG PS) of 0 – 1, and adequate bone marrow and organ function. Additionally, patients with history of brain metastases are eligible provided they have been definitively treated, are asymptomatic, and clinically stable. Approximately 300 patients will be randomly assigned 1:1 to receive amivantamab/carboplatin/pemetrexed (Arm A) or carboplatin/pemetrexed (Arm B). Randomization will be stratified by ECOG PS (0 or 1), history of brain metastases (yes or no), and prior EGFR TKI (yes or no). Patients in Arm A will be treated with amivantamab/carboplatin/pemetrexed in a 21-day cycle for 4 cycles followed by maintenance with amivantamab and pemetrexed until disease progression or any of the treatment discontinuation criterion is met. Similarly, patients in Arm B will receive treatment with carboplatin/pemetrexed in a 21-day cycle for 4 cycles followed by maintenance therapy with pemetrexed alone. Crossover from the chemotherapy arm to monotherapy amivantamab may be allowed. The primary endpoint of the study is progression-free survival (PFS) as assessed by blinded independent central review according to RECIST v1.1. Key secondary endpoints include objective response rate and overall survival. Safety assessments will include monitoring adverse events and laboratory abnormalities. Exon20ins, amivantamab, chemotherapy

Impact of the generation of EGFR-TKIs administered as prior therapy on the efficacy of osimertinib in patients with non-small cell lung cancer harboring EGFR T790M mutation.

BackgroundThere are few studies that directly compare the effects of osimertinib on patients with non‐small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) T790M mutation between the generation of prior EGFR tyrosine kinase inhibitors (TKIs).MethodsWe retrospectively reviewed clinical data from the medical records of consecutive patients with advanced NSCLC who had developed resistance to first‐ or second‐generation EGFR‐TKIs due to EGFR T790M mutation and were subsequently treated with osimertinib at Juntendo University Hospital. In patients with available tumor samples, target amplicon sequencing analyses were performed to explore the genetic biomarkers.ResultsA total of 38 patients with NSCLC harboring EGFR T790M mutation were treated with osimertinib. Eight patients were classified into group A (afatinib followed by osimertinib) and 30 patients were classified into group B (first‐generation EGFR‐TKI followed by osimertinib). Progression‐free survival (PFS) was significantly longer in group A than in group B (median PFS; not reached vs. 11.0 months, P = 0.018). Fourteen patients had available tissue samples collected before osimertinib treatment for target sequencing. In group A we found no additional mutations, other than EGFR T790M mutation. On the other hand, there were three samples in which other mutations emerged, in addition to EGFR T790M mutation, in group B.ConclusionsPFS of osimertinib was significantly longer in patients with NSCLC harboring EGFR T790M mutation after treatment with afatinib than in patients after treatment with first generation EGFR‐TKIs. Additional mutations other than EGFR T790M may affect the efficacy of osimertinib treatment.Key pointsSignificant findings of the study:PFS of osimertinib was significantly longer in patients with NSCLC harboring EGFR T790M mutation after treatment with afatinib than in patients after treatment with first generation EGFR‐TKIs.What this study adds:Additional mutations other than EGFR T790M may affect the efficacy of osimertinib treatment.

Characteristics of patients with EGFR-mutant non-small-cell lung cancer who benefited from immune checkpoint inhibitors.

Immune checkpoint inhibitors (ICIs) are less effective in non-small-cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations. However, a small percentage of patients with EGFR-mutant NSCLC do respond, and the characteristics of these patients are not known. Here, we identify the characteristics of patients who may respond to ICI therapy for EGFR-mutant NSCLC. The medical records of NSCLC patients with EGFR mutations who received PD-1/PD-L1 antibody monotherapy at nine institutions were reviewed. In total, 58 patients with EGFR-mutant NSCLC were analyzed. Various clinical factors such as smoking history and EGFR mutation type were not associated with progression-free survival (PFS) of ICIs, while the PFS of prior EGFR tyrosine kinase inhibitors (TKIs) was inversely associated with that of ICIs. Patients who responded to prior EGFR TKIs for > 10months exhibited a significantly shorter response to ICIs compared to those who had responded for ≤ 10months (PFS of ICI: 1.6 vs. 1.9months; hazard ratio: 2.54; 95% confidence interval 1.26-5.12; p = 0.009). However, patients who responded to ICIs for > 6months responded to prior EGFR TKIs for significantly shorter periods compared to those who responded to ICIs for ≤ 6months (PFS of prior EGFR TKI: 5.3 vs. 12.1months; log-rank test: p = 0.0025). The duration of response to prior EGFR TKIs could be a predictive marker of ICI therapy in EGFR-mutant NSCLC patients.

A phase II, multicenter, two cohort study of 160 mg osimertinib in EGFR T790M-positive non-small-cell lung cancer patients with brain metastases or leptomeningeal disease who progressed on prior EGFR TKI therapy

Up to 40% of patients with non-small-cell lung cancer (NSCLC) and epidermal growth factor receptor (EGFR) mutations treated with EGFR tyrosine kinase inhibitors (TKIs) present with disease progression in the central nervous system (CNS), either as brain metastases (BM) or leptomeningeal metastases (LM). Osimertinib (80 mg), a third-generation, irreversible, oral EGFR TKI, has shown efficacy in active CNS metastases. However, efficacy of osimertinib 160 mg in BM or LM is unclear. This prospective, single-arm, two cohort study evaluated the efficacy of osimertinib 160 mg in T790M-positive BM or LM NSCLC patients who progressed on prior EGFR TKI (NCT03257124) treatment. The primary end points were objective response rate (ORR) (H1= 30%) for the BM cohort and overall survival (OS) (H1= 5 months) for the LM cohort. The median follow-up duration was 10.1 months and 9.6 months for the BM and LM cohorts, respectively. In the BM cohort, intracranial ORR and disease control rate were 55.0% and 77.5%, respectively. The median progression-free survival (PFS) was 7.6 months [95% confidence interval (CI) 5.0-16.6]; the median OS was 16.9 months [95% CI 7.9-not reached (NR)]. In the LM cohort, intracranial disease control rate was 92.5% and complete response rate was 12.5%. The median OS was 13.3 months (95% CI 9.1-NR); the median PFS was 8.0 months (95% CI 7.2-NR). Subgroup analyses based on previous exposure to T790M-targeting agents, including osimertinib 80 mg or other third-generation EGFR TKIs, showed no difference in PFS in both the BM (n= 18, P= 0.39) and LM (n= 17, P=0.85) cohorts. Previous radiotherapy favored PFS in the BM cohort (hazard ratio 0.42, P= 0.04). The most common adverse events were decreased appetite, diarrhea, and skin rash; however, most were grade 1-2. Thus, osimertinib 160 mg demonstrated promising ORR and survival benefit with a tolerable safety profile in EGFR T790M-positive NSCLC patients with CNS metastasis who progressed on prior EGFR TKIs.

Intracranial anti-tumor activity of lazertinib in patients with advanced NSCLC who progressed after prior EGFR TKI therapy: Data from a phase I/II study.

9571 Background: Lazertinib (YH25448) is a highly mutant-selective, irreversible 3rd-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that targets the activating EGFR mutations (Del19 and L858R), as well as the T790M mutation, while sparing wild type. Brain metastasis (BM) are common in patients (pts) with advanced NSCLC. Lazertinib showed a high blood-brain barrier penetration profile in preclinical studies. We report intracranial response data in pts with advanced NSCLC from a Phase I/II study of lazertinib (NCT03046992). Methods: Pts with advanced NSCLC, who had progressed after prior EGFR-TKI therapy, were enrolled in an open-label, multicenter, phase I/II study with dose-escalation, dose-expansion and dose-extension phases. Brain MRI was done in all pts at baseline. Pts with asymptomatic BM were eligible for enrollment. Intracranial anti-tumor activity of lazertinib was analysed in pts with BM present on baseline brain scan. Pre-defined intracranial endpoints included objective intracranial response rate (OIRR) and intracranial progression-free survival (IPFS) by independent central review (ICR). The brain metastasis full analysis population included pts with measurable and/or non-measurable BM lesion present on baseline brain scan; the brain metastasis population evaluable for response included only pts with measurable BM lesion. Results: As of 30 Sep 2019, a total of 181 pts received at least one dose of lazertinib 20-320 mg across 7 dose levels. Of those, 64 pts (56% female, median age 63, 86% T790M mutation positive by central testing) were included in the brain metastasis full analysis population; Intracranial disease control rate (IDCR) was 90.6% (58/64; 95% CI 83.5, 97.8) and median IPFS was not reached (95% CI 14.0, NR). In the brain metastasis population evaluable for response, a total of 22 pts were included; OIRR and IDCR were 54.5% (12/22; 95% CI 33.7, 75.4) and 90.9% (20/22; 95% CI 78.9, 100), respectively. In 13 pts (7.2%) out of 181 pts, brain was the first site of disease progression by existing and/or new lesions. Conclusions: Lazertinib demonstrated clinically meaningful activity against BM, aligned with preclinical data. Clinical trial information: NCT03046992 .

Complex EGFR mutations with secondary T790M mutation confer shorter osimertinib progression-free survival and overall survival in advanced non-small cell lung cancer

ObjectivesOsimertinib is active against epidermal growth factor receptor (EGFR) T790M-mutated non-small cell lung cancer (NSCLC). However, its efficacy against complex EGFR mutations with T790M has not been evaluated. Materials and methodsIn order to detect complex EGFR mutations, we consecutively sequenced cancer tissues by RNA reverse transcription polymerase chain reaction. Patients with advanced NSCLC with activating EGFR mutation and secondary T790M who received osimertinib were enrolled. Patients’ clinicopathologic characteristics, prior treatment details, and osimertinib treatment outcomes were analyzed. ResultsTotally, 165 sequenced patients were analyzed. Eleven (7%) of them had complex EGFR mutations with T790M. The osimertinib response rate was 27%. They had a shorter progression-free survival (PFS) (median, 2.9 and 9.7 months, p < 0.001) and overall survival (OS) (median, 17.8 and 31.0 months, p = 0.01) than patients with a single EGFR mutation with T790M. After osimertinib failure, seven patients received rebiopsy with molecular analysis. Four lost the T790M, two transformed to small cell and one acquired C797S. Moreover, taking the median as the demarcation, patients received shorter prior EGFR tyrosine kinase inhibitor (TKI) treatment duration had a shorter osimertinib PFS (median, 7.3 and 13.8 months, p < 0.001) and OS (median, 21.5 and 36.7 months, p = 0.003). Multivariate Cox regression analysis confirmed complex EGFR mutations and prior EGFR TKI treatment duration were independent factors for osimertinib PFS and OS. ConclusionsComplex EGFR mutations and shorter prior EGFR TKI treatment duration may confer shorter osimertinib PFS and OS in advanced NSCLC with secondary T790M mutation.

Prior EGFR-TKI Treatment in EGFR-Mutated NSCLC Affects the Allele Frequency Fraction of Acquired T790M and the Subsequent Efficacy of Osimertinib.

The first (1G) and second (2G) generations of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) show differential inhibitory capacities towards EGFR T790M-mutated non-small-cell lung cancer (NSCLC) cells. To assess the ratio of the allele fractions of T790M (AFT790M) to EGFR-activating mutations (AFmEGFR) in patients treated with 1G and 2G EGFR TKIs who acquired T790M-mediated resistance and to determine the relationship between AF and the later efficacy of osimertinib. The efficacy of osimertinib was reviewed for 54 T790M-positive EGFR-mutated NSCLC patients grouped by the generation of prior EGFR TKI use (1G vs. 2G). AFmEGFR and AFT790M were determined by QuantStudio digital PCR using tissues obtained upon acquired resistance. The progression-free survival (PFS; 20.3 vs. 11.6months, p = 0.031) and the 1-year PFS rate (63.2 vs. 37.5%, p = 0.029) for osimertinib were significantly better for group 1G compared to group 2G. The ratio of AFT790M to AFmEGFR in group 1G was significantly higher than in group 2G (46.16 ± 5.40% vs. 25.86 ± 4.25%, p = 0.009). An unbiased analysis revealed three AF-associated clusters (ARCs) suggesting the ratio of AFT790M to AFmEGFR correlates with the efficacy of osimertinib. We found all patients in ARC2 having the highest ratio of AFT790M to AFmEGFR to have previously been treated with a 1G EGFR TKI and to show the longest osimertinib PFS compared to ARC3 (NR vs. 11.9months, p = 0.060) and ARC1 (NR vs. 12.4month, p = 0.045). Acquired T790M fraction of EGFR-mutated NSCLC is linked to different generations of prior EGFR TKI use and the later efficacy of osimertinib.