Predictive and prognostic significance of PIOS (Patras Immunotherapy Score) model in patients with advanced NSCLC treated with nivolumab or pembrolizumab: Results from a validation cohort

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Background: The treatment of advanced non-small cell lung cancer (aNSCLC) has tremendously changed during the last few years, especially, since immune checkpoint inhibitors (ICIs) were incorporated in the daily clinical practice. However, clinical useful biomarkers remain an unmet need. Recently, our group established and proposed a new score, Patras Immunotherapy Score (PIOS), which was found to have predictive and prognostic value in a discovery group with aNSCLC patients treated with nivolumab or pembrolizumab. The objective of the current study was to validate our initial observation and confirm the clinical significance of PIOS formula in an external and multicentric cohort of aNSCLC patients. Methods: PIOS is a baseline formula derived by combining the following non-interventional clinical parameters, Performance Status (PS), Body Mass Index (BMI), age and Line Of Treatment (LOT) and it is calculated as PIOS = (PS×BMI)/(LOT×AGE). In the current multicenter study, 626 aNSCLC patients, treated with nivolumab or pembrolizumab monotherapy, were retrospectively selected, blindly to the clinical outcome, and enrolled. The primary endpoints of this study were to investigate the predictive and prognostic value of PIOS in terms of progression free survival (PFS), overall survival (OS) and best overall response. Results: Firstly, PIOS was associated with best overall response. Following a two-tier model, patients who had progressed (PD) had lower scores than those with stable disease (SD), partial response (PR) or complete response (CR) (p < 0.001). This association remained significant using a four-tier model (PD, SD, PR and CR) for evaluation of best overall response (p < 0.001). In addition, predictive significance of PIOS score also persisted using a binary logistic regression analysis, adjusted for disease stage and PD-L1 status (p = 0.002, OR 0.578, 95% CI 0.408-0.821). Furthermore, patients with higher PIOS score had longer PFS compared to patients with lower PIOS score (ΗΡ 0.621, 95% CI 0.470-0.821, p = 0.001), while multivariate analysis for PFS, adjusted for clinical stage and PD-L1, confirmed the predictive value of PIOS score (HR 0.651, 95% CI 0.492-0.863, p = 0.003). Moreover, PIOS score was also associated with prognosis (p < 0.001). The median OS for the favorable group was 778 days compared to 341 days for the unfavorable group with low PIOS score (HR = 0.608, 95% CI 0.482-0.766, p < 0.001) at univariate analysis. This association remained statistically significant (HR 0.620, 95% CI 0.492-0.783, p < 0.001) after adjusting for PD-L1 expression. Conclusions: These data provide further validation for PIOS as predictive and prognostic biomarker in aNSCLC patients treated with nivolumab or pembrolizumab monotherapy.

Poor performance status and front-line pembrolizumab in advanced non-small-cell lung cancer (NSCLC) patients with PD-L1>50%

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Background: We retrospectively analysed real-world clinical outcomes of patients with advanced non-small-cell lung cancer (NSCLC) harbouring high PD-L1 expression ( > 50%) and treated with first-line pembrolizumab, following the Keynote 024 regimen. In the recent PePS2 trial and Checkmate 817, we see that some patients with PS2 could benefit from a durable response to checkpoint inhibitors. However, current data does not suggest an improvement in median OS compared to historical data on chemotherapy in this setting. Methods: Data was collected by 16 participating centers. The trial was approved by local ethics committees and patients included signed a general consent form. All patients with NSCLC with PD-L1 expression ≥50%, treated with first-line pembrolizumab were included, from the introduction of first-line pembrolizumab to the present. We collected medical data from patient files, pathology reports and laboratory reports for all patients. Patient characteristics, comorbidities, Eastern Cooperative Oncology Group (ECOG) performance status (PS), and tumor characteristics were reported. Overall survival (OS) was calculated from the date of the first cycle of pembrolizumab to death and estimated through the Kaplan-Meier method. Results: 302 patients were identified, of which 247 with a PS of 0-1, 52 with a PS of 2. Patients (3) with PS3 were excluded. The median age was 69 with a range from 19 to 87 years. There were 193 males and 106 females, 90% were active or former smokers, 19% had brain lesions at diagnosis. Only 14% received brain radiotherapy. Median OS was 7.2 months among patients with PS2, while not reached for those with PS0-1 (HR 3.80, 95% confidence interval 2.49-5.78). Conclusions: Patients with a PS of 2 had significantly worse survival than those with PS0-1. The retrospective nature of our trial and lack of a control arm treated with chemotherapy do not allow us to postulate as to whether PS is predictive or prognostic. Our data suggests worse survival among NSCLC patients with PS2 treated with front-line pembrolizumab. A prospective randomized trial comparing immunotherapy to chemotherapy or chemo-immunotherapy in this population would be welcome.

Lungful: An observational prospective study to assess the molecular epidemiology of EGFR mutations upon progression on or after first line EGFR-TKI therapy, in real-life clinical settings in Greece

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Background: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the gold standard 1st line strategy for non-small-cell lung cancer (NSCLC) patients with activating EGFR mutations (EGFRm), associated with improved survival outcomes and quality of life compared to chemotherapy. Despite the high response rate with first- and second- generation TKIs, most patients develop resistance to treatment and progress. The acquisition of T790M mutation in exon 20 is considered the most common resistance mechanism. This study aims to investigate the molecular epidemiology of EGFR resistance mutations, focusing on T790M in EGFRm NSCLC patients treated with TKIs. Methods: The study included patients with locally advanced/metastatic EGFRm NSCLC who have progressed on or after 1st line treatment with first- or second- generation TKI. Samples either from plasma-based liquid biopsy and/or tissue re-biopsy were analysed using the Cobas EGFR Mutation Test v2. All patients signed informed consent and were enrolled between July 2017 and September 2019. Statistical analyses were performed using SAS software, Version 9.4. Results: Ninety-six eligible patients were enrolled. At the time of progression, T790M mutation was detected in 16.7%of the patients using plasma-based liquid biopsies. Among patients with negative T790M result, in plasma, tissue re-biopsy was performed in 22,7% with evaluable/valid results in 72.2% of them. T790M mutation was identified in 38.5% of re-biopsy samples. According to Cobas EGFR Mutation test results (combined plasma and tissue), T790M mutation was identified in 21.9% of the patients. Of T790M-positive patients 42.9% had previously received first and 57.1% second generation EGFR-TKI. Conclusions: Results from this study in real world clinical setting in Greece, show that EGFR-T790M acquired resistance positivity rate in plasma is lower compared to previous reports. Moreover, these data underline the challenges of implementing precision medicine using tissue re-biopsy in advanced/metastatic NSCLC. Clinical trial information: D133FR00126. [Table: see text]