Exploring the impact of patient-specific clinical features on osimertinib effectiveness in a real-world cohort of patients with EGFR mutated non-small cell lung cancer

Osimertinib is prescribed to patients with metastatic non-small cell lung cancer (NSCLC) and a sensitizing EGFR mutation. Limited data exists on the impact of patient characteristics or osimertinib exposure on effectiveness outcomes. This was a Dutch, multicenter cohort study. Eligible patients were ≥18 years, with metastatic EGFRm+ NSCLC, receiving osimertinib. Primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS) and safety. Kaplan-Meier analyses and multivariate Cox proportional hazard models were performed. In total, 294 patients were included. Primary EGFR-mutations were mainly exon 19 deletions (54%) and p.L858R point mutations (30%). Osimertinib was given in first-line (40%), second-line (46%) or beyond (14%), with median PFS 14.4 (95% CI: 9.4-19.3), 13.9 (95% CI: 11.3-16.1) and 8.7 months (95% CI: 4.6-12.7), respectively. Patients with low BMI (<20.0 kg/m2 ) had significantly shorter PFS/OS compared to all other subgroups. Patients with a high plasma trough concentration in steady state (Cmin,SS ; >271 ng/mL) had shorter PFS compared to a low Cmin,SS (<163 ng/mL; aHR 2.29; 95% CI: 1.13-4.63). A significant longer PFS was seen in females (aHR = 0.61, 95% CI: 0.45-0.82) and patients with the exon 19 deletion (aHR = 0.58, 95% CI: 0.36-0.92). A trend towards longer PFS was seen for TP53 wild-type patients, while age did not impact PFS. Patients with a primary EGFR exon 19 deletion had longer PFS, while a low BMI, male sex and a high Cmin,SS were indicative for shorter PFS and/or OS. Age was not associated with effectiveness outcomes of osimertinib.

Incidence of Bone Metastases and Skeletal-Related Events in Patients With EGFR-Mutated NSCLC Treated With Osimertinib

Introduction

Bone metastases are frequent in patients with EGFR-mutated (EGFR+) NSCLC. Skeletal-related events (SREs) are common in these patients; however, no data on SRE in osimertinib-treated patients are reported. We investigated the development of bone metastases and SREs in patients with EGFR+ NSCLC treated with osimertinib.

Methods

This is a retrospective multicenter cohort study that included patients with metastatic EGFR+ NSCLC who were treated with osimertinib between February 2016 and September 2021. Demographics, bone metastases-related outcomes, SREs, treatment efficacy, and overall survival (OS) were collected.

Results

In total, 250 patients treated with osimertinib (43% first line) were included. Of the patients, 51% had bone metastases at initiation of osimertinib. Furthermore, 16% of the patients with bone metastases used bone-targeted agents. Median follow-up from initiation of osimertinib was 23.4 months (95% confidence interval [CI]: 19.9-26.9 mo). During osimertinib treatment, 10% developed new bone metastases or bone progression. Of the patients with bone metastases, 39% had more than or equal to one SREs: 28% developed first SRE before osimertinib treatment, 1% after, and 11% during. Median OS post-bone metastasis was 30.8 months (95% CI: 21.9-39.7). Median OS after first SRE was 31.1 months (95% CI: 15.8-46.5).

Conclusions

Bone metastases and SREs are frequent before and during treatment with osimertinib in EGFR+ NSCLC. Because of these findings and the long OS post-bone metastases, we advocate prescription of bone-targeted agents in these patients and recommend adding bone-specific end points in clinical trials.

High dose osimertinib in patients with advanced stage EGFR exon 20 mutation-positive NSCLC: Results from the phase 2 multicenter POSITION20 trial

INTRODUCTION

Patients with life-threatening advanced non-small cell lung cancer (NSCLC) who harbor an exon 20 deletion and/or insertion mutation (EGFRex20 + ) have limited effective treatment options. The high dose 3rd generation tyrosine kinase inhibitor (TKI) osimertinib shows promising in vitro activity in EGFRex20 + NSCLC tumors.

METHODS

The POSITION20 is a single arm phase II, multicenter study investigating 160 mg osimertinib in patients with EGFRex20+, T790M negative NSCLC. We allowed patients to be treatment naïve and to have asymptomatic brain metastases. The primary endpoint was overall response rate (ORR). Secondary outcomes were duration of response (DoR), progression free survival (PFS), overall survival (OS), and treatment related adverse events (trAEs).

RESULTS

From June 2018 to October 2021, 25 patients were enrolled across five centers in the Netherlands. The median age was 70 years (range, 47-87), 20 patients (80%) were women, and the median number of previous lines of therapy was 1 (range, 0-3). The exon 20 mutations were clustered between A763 and L777. The most common exon 20 mutations were p.(N771_H773dup) (n = 3) and p.(A767_V769dup) (n = 3). The ORR was 28% (95% CI, 12-49%), including seven partial responses, with a median DoR of 5.3 months (range, 2.7-27.6). The median PFS was 6.8 months (95% CI, 4.6-9.1) and the median OS was 15.2 months (95% CI, 14.3-16.0). The most common trAEs were diarrhea (72%), dry skin (44%), and fatigue (44%). The primary reason for discontinuation was progressive disease in 14 patients (56%).

CONCLUSION

The POSITION20 study showed modest antitumor activity in patients with EGFRex20 + NSCLC treated with 160 mg osimertinib, with a confirmed ORR of 28% and acceptable toxicity.

Improving the tolerability of osimertinib by identifying its toxic limit

Background:

Osimertinib is the cornerstone in the treatment of epidermal growth factor receptor-mutated non-small cell lung cancer (NSCLC). Nonetheless, ±25% of patients experience severe treatment-related toxicities. Currently, it is impossible to identify patients at risk of severe toxicity beforehand. Therefore, we aimed to study the relationship between osimertinib exposure and severe toxicity and to identify a safe toxic limit for a preventive dose reduction.

Methods:

In this real-life prospective cohort study, patients with NSCLC treated with osimertinib were followed for severe toxicity (grade ⩾3 toxicity, dose reduction or discontinuation, hospital admission, or treatment termination). Blood for pharmacokinetic analyses was withdrawn during every out-patient visit. Primary endpoint was the correlation between osimertinib clearance (exposure) and severe toxicity. Secondary endpoint was the exposure–efficacy relationship, defined as progression-free survival (PFS) and overall survival (OS).

Results:

In total, 819 samples from 159 patients were included in the analysis. Multivariate competing risk analysis showed osimertinib clearance (c.q. exposure) to be significantly correlated with severe toxicity (hazard ratio 0.93, 95% CI: 0.88–0.99). An relative operating characteristic curve showed the optimal toxic limit to be 259 ng/mL osimertinib. A 50% dose reduction in the high-exposure group, that is 25.8% of the total cohort, would reduce the risk of severe toxicity by 53%. Osimertinib exposure was not associated with PFS nor OS.

Conclusion:

Osimertinib exposure is highly correlated with the occurrence of severe toxicity. To optimize tolerability, patients above the toxic limit concentration of 259 ng/mL could benefit from a preventive dose reduction, without fear for diminished effectiveness.

The development of the ADO-SQ model to predict 1-year mortality in patients with COPD

BACKGROUND

Goals of end-of-life care must be adapted to the needs of patients with chronic obstructive pulmonary disease (COPD) who are in the last phase of life. However, identification of those patients is limited by moderate performances of existing prognostic models and by limited validation of the often-recommended surprise question.

AIM

To develop a clinical prediction model to predict 1-year mortality in patients with COPD.

DESIGN

Prospective study using logistic regression to develop a model in two steps: (1) external validation of the ADO, BODEX, or CODEX models (A = age; B = body mass index; C = comorbidity; D = dyspnea; EX = exacerbations; O = airflow obstruction); (2) updating of best performing model and extending it with the surprise question. Discriminative performance of the new model was assessed using internal-external validation and measured with area under the curve (AUC). A nomogram and web application were developed.

SETTINGS/PARTICIPANTS

Patients with COPD from five hospitals (September-November 2017).

RESULTS

Of the 358 included patients (median age 69.5 years, 50% male), 63 (17%) died within a year. The ADO index (AUC 0.73) had the best discriminative ability compared to the BODEX (AUC 0.71) or CODEX (AUC 0.68), and was extended with the surprise question. The resulting ADO-surprise question (SQ) model had an AUC of 0.79.

CONCLUSION

The ADO-SQ model offers improved discriminative performance for predicting 1-year mortality compared to the surprise question, ADO, BODEX, or CODEX. A user-friendly nomogram and web application (https://dnieboer.shinyapps.io/copd) were developed. Further external validation of the ADO-SQ in patient groups is needed.

Genetic polymorphism in ATIC is associated with effectiveness and toxicity of pemetrexed in non-small-cell lung cancer

Patients with advanced non-small-cell lung cancer who are treated with pemetrexed display a wide variation in clinical response and toxicity. In this prospective, multicentre cohort study, we investigated the association with treatment effectiveness and toxicity of 10 polymorphisms in nine candidate genes, covering the folate pathway (MTHFR), cell transport (SLC19A1/ABCC2/ABCC4), intracellular metabolism (FPGS/GGH) and target enzymes (TYMS/DHFR/ATIC) of pemetrexed. Adjusted for sex, ECOG performance score and disease stage, the association between ATIC (rs12995526) and overall survival (HR 1.59, 95% CI 1.06 to 2.39) was significant. Regarding toxicity, this ATIC polymorphism was significantly associated with severe laboratory (p=0.014) and clinical (p=0.016) chemotherapy-related adverse events, severe neutropenia (p=0.007) and all-grade diarrhoea (p=0.034) in multivariable analyses.

Plasma Predictive Features in Treating EGFR-Mutated Non-Small Cell Lung Cancer

Although epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are the preferred treatment for patients with EGFR-mutated non-small cell lung cancer (NSCLC), not all patients benefit. We therefore explored the impact of the presence of mutations found in cell-free DNA (cfDNA) and TKI plasma concentrations during treatment on progression-free survival (PFS). In the prospective START-TKI study blood samples from 41 patients with EGFR-mutated NSCLC treated with EGFR-TKIs were available. Next generation sequencing (NGS) on cfDNA was performed, and plasma TKI concentrations were measured. Patients without complete plasma conversion of EGFR mutation at week 6 had a significantly shorter PFS (5.5 vs. 17.0 months, p = 0.002) and OS (14.0 vs. 25.5 months, p = 0.003) compared to patients with plasma conversion. In thirteen (second line) osimertinib-treated patients with a (plasma or tissue) concomitant TP53 mutation at baseline, PFS was significantly shorter compared to six wild-type cases; 8.8 vs. 18.8 months, p = 0.017. Erlotinib Cmean decrease of ≥10% in the second tertile of treatment was also associated with a significantly shorter PFS; 8.9 vs. 23.6 months, p = 0.037. We obtained evidence that absence of plasma loss of the primary EGFR mutation, isolated plasma p.T790M loss after six weeks, baseline concomitant TP53 mutations, and erlotinib Cmean decrease during treatment are probably related to worse outcome.

Plasma Cell-Free DNA Testing of Patients With EGFR Mutant Non–Small-Cell Lung Cancer: Droplet Digital PCR Versus Next-Generation Sequencing Compared With Tissue-Based Results

PURPOSE

To compare the results of plasma cell-free DNA (cfDNA) droplet digital PCR (ddPCR) and next-generation sequencing (NGS) on detection of epidermal growth factor receptor ( EGFR) primary activating mutations and p.T790M with results of tissue analysis in patients with EGFR mutated non–small-cell lung cancer.

METHODS

All patients with EGFR mutated non–small cell lung cancer for which a pathology and a plasma specimen were available upon progression between November 2016 and July 2018 were selected. Concordance, Cohen’s κ, and intraclass correlation coefficients were calculated.

RESULTS

Plasma cfDNA and pathology specimens of 36 patients were analyzed. Agreement between ddPCR and NGS was 86% (κ = 0.63) for the primary activating mutation and 94% (κ = 0.89) for the p.T790M detection. Allele ratios were comparable, with an intraclass correlation coefficient of 0.992 and 0.997, respectively. Discrepancies of some degree were found in 15 patients (41.7%). In six patients (16.7%), no mutations were detected in cfDNA. In three patients (8.3%), p.T790M was detected in plasma but not in the pathology specimen, whereas in three other patients (8.3%), p.T790M was demonstrated in the pathology specimen but not in plasma. Concordance of cfDNA and pathology for the primary activating mutation was 69% for ddPCR and 83% for NGS. For the detection of p.T790M, this was 75% (κ = 0.49) for ddPCR as well as for NGS.

CONCLUSION

Mutual agreement is high between NGS and ddPCR in cfDNA on the level of a specific mutation, with comparable ratio results. Plasma testing of EGFR primary activating mutations and p.T790M shows high concordance with pathology results, for NGS as well as for ddPCR, depending on the extent of the panel used. In NGS, more genetic aberrations can be investigated at once.

Improved diagnosis and prognostication of patients with pleural malignant mesothelioma using biomarkers in pleural effusions and peripheral blood samples - a short report

Purpose

There is a lack of robust and clinically utilizable markers for the diagnosis and prognostication of malignant pleural mesothelioma (MPM). This research was aimed at optimizing and exploring novel approaches to improve the diagnosis and prognostication of MPM in pleural effusions and peripheral blood samples.

Methods

CellSearch-based and flow cytometry-based assays using melanoma cell adhesion molecule (MCAM) to identify circulating tumor cells (CTCs) in pleural effusions and peripheral blood samples of MPM patients were optimized, validated, explored clinically and, in case of pleural effusions, compared with cytological analyses. Additionally, tumor-associated circulating endothelial cells (CECs) were measured in peripheral blood samples. The assays were performed on a MPM cohort encompassing patients with histology-confirmed MPM (n=27) and in a control cohort of patients with alternative diagnoses (n=22). Exploratory analyses on the prognostic value of all assays were also performed.

Results

The malignancy of MCAM-positive cells in pleural effusions from MPM patients was confirmed. The detection of MPM CTCs in pleural effusions by CellSearch showed a poor specificity. The detection of MPM CTCs in pleural effusions by flow cytometry showed a superior sensitivity (48%) to standard cytological analysis (15%) (p = 0.03). In peripheral blood, CTCs were detected in 26% of the MPN patients, whereas in 42% of the MPM patients tumor-associated CECs were detected above the upper limit of normal (ULN). In exploratory analyses the absence of CTCs in pleural effusions, and tumor-associated CECs in peripheral blood samples above the ULN, appeared to be associated with a worse overall survival.

Conclusion

MCAM-based flow cytometric analysis of pleural effusions is more sensitive than routine cytological analysis. Flow cytometric analysis of pleural effusions and tumor-associated CECs in peripheral blood may serve as a promising approach for the prognostication of MPM patients and, therefore, warrants further study.

Electronic supplementary material

The online version of this article (doi:10.1007/s13402-017-0327-7) contains supplementary material, which is available to authorized users.

One year experience of MET gene exon 14 skipping analysis in lung cancer: Identification of 18 cases by NGS

e20055

Background: Lung adenocarcinoma (LAC) is the most common histological type of non-small-cell lung cancer and is one of the malignancies with the most evolved personalized treatments based on molecular characteristics of the tumor. Mutations in EGFR, HER2 and BRAF, specific translocations of ALK, ROS1, RET and amplification of MET all have standard diagnostic importance and lead to specific treatment options for the individual LAC patients. Recently, in 2-4% of LAC MET gene mutations leading to skipping of exon 14 were found. These mutations were described to occur more frequently in tumors with sarcomatoid histology. LAC with MET exon 14 skipping mutations showed impressive, although temporary, responses to MET tyrosine kinase inhibitors (TKI) crizotinib, cabozantinib and capmatinib. We will present our experience with routine molecular diagnostic detection of the most common MET exon 14 skipping mutations. Methods: In January 2016 we included in our standard, DNA based, molecular diagnostics custom-made NGS analyses 4 amplicons for detection of MET skipping mutations. The analyses were performed on microdissected FFPE tissue sections or routine histology or cytology stained preparations. Nine different mutations were validated for their effect on splicing by RT-PCR on RNA isolated from the same tissue samples. Results: Between January 2016 and January 2017 676 routine molecular diagnostic analyses on LAC were performed. In 18 (2.7%) cases MET mutations were detected possibly resulting in exon 14 skipping. Nine out of 16 different mutations were tested by RT-PCR and all 9 were demonstrated to result in MET exon 14 skipping. Conclusions: MET exon 14 skipping mutations can reliably be detected in routine pathology tissue samples. These analyses can easily be included in routine molecular diagnostic NGS. When necessary, confirmation of the mutational effect on RNA splicing can be implemented as well. Routine identification of MET skipping mutations (2.7% of cases) adds substantially to the personalized targeted treatment strategies for LAC patients.

Influence of the Acidic Beverage Cola on the Absorption of Erlotinib in Patients With Non-Small-Cell Lung Cancer

PURPOSE

Erlotinib depends on stomach pH for its bioavailability. When erlotinib is taken concurrently with a proton pump inhibitor (PPI), stomach pH increases, which results in a clinically relevant decrease of erlotinib bioavailability. We hypothesized that this drug-drug interaction is reversed by taking erlotinib with the acidic beverage cola. The effects of cola on erlotinib bioavailability in patients not treated with a PPI were also studied.

PATIENTS AND METHODS

In this randomized, cross-over, pharmacokinetic study in patients with non-small-cell lung cancer, we studied intrapatient differences in absorption (area under the plasma concentration time curve [AUC0-12h]) after a 7-day period of concomitant treatment with erlotinib, with or without esomeprazole, with either cola or water. At the 7th and 14th day, patients were hospitalized for 1 day for pharmacokinetic sampling.

RESULTS

Twenty-eight evaluable patients were included in the analysis. In patients treated with erlotinib and esomeprazole with cola, the mean AUC0-12h increased 39% (range, -12% to 136%; P = .004), whereas in patients not treated with the PPI, the mean AUC0-12h was only slightly higher (9%; range, -10% to +30%; P = .03) after erlotinib intake with cola.

CONCLUSION

Cola intake led to a clinically relevant and statistically significant increase in the bioavailability of erlotinib during esomeprazole treatment. In patients not treated with the PPI, the effects of cola were marginal. These findings can be used to optimize the management of drug-drug interactions between PPIs and erlotinib.

Gene expression-based classification of non-small cell lung carcinomas and survival prediction

Background

Current clinical therapy of non-small cell lung cancer depends on histo-pathological classification. This approach poorly predicts clinical outcome for individual patients. Gene expression profiling holds promise to improve clinical stratification, thus paving the way for individualized therapy.

Methodology and Principal Findings

A genome-wide gene expression analysis was performed on a cohort of 91 patients. We used 91 tumor- and 65 adjacent normal lung tissue samples. We defined sets of predictor genes (probe sets) with the expression profiles. The power of predictor genes was evaluated using an independent cohort of 96 non-small cell lung cancer- and 6 normal lung samples. We identified a tumor signature of 5 genes that aggregates the 156 tumor and normal samples into the expected groups. We also identified a histology signature of 75 genes, which classifies the samples in the major histological subtypes of non-small cell lung cancer. Correlation analysis identified 17 genes which showed the best association with post-surgery survival time. This signature was used for stratification of all patients in two risk groups. Kaplan-Meier survival curves show that the two groups display a significant difference in post-surgery survival time (p = 5.6E-6). The performance of the signatures was validated using a patient cohort of similar size (Duke University, n = 96). Compared to previously published prognostic signatures for NSCLC, the 17 gene signature performed well on these two cohorts.

Conclusions

The gene signatures identified are promising tools for histo-pathological classification of non-small cell lung cancer, and may improve the prediction of clinical outcome.

Integration of single-fiber reflectance spectroscopy into ultrasound-guided endoscopic lung cancer staging of mediastinal lymph nodes

We describe the incorporation of a single-fiber reflectance spectroscopy probe into the endoscopic ultrasound fine-needle aspiration (EUS-FNA) procedure utilized for lung cancer staging. A mathematical model is developed to extract information about the physiological and morphological properties of lymph tissue from single-fiber reflectance spectra, e.g., microvascular saturation, blood volume fraction, bilirubin concentration, average vessel diameter, and Mie slope. Model analysis of data from a clinical pilot study shows that the single-fiber reflectance measurement is capable of detecting differences in the physiology between normal and metastatic lymph nodes. Moreover, the clinical data show that probe manipulation within the lymph node can perturb the in vivo environment, a concern that must be carefully considered when developing a sampling strategy. The data show the feasibility of this novel technique; however, the potential clinical utility has yet to be determined.