23 Validation of PD-L1 dynamic expression on extracellular vesicles as a predictor of response to immune-checkpoint inhibitors and survival in non-small cell lung cancer patients

BackgroundImmune-checkpoint inhibitors (ICIs) revolutionized the treatment of advanced non-small cell lung cancer (NSCLC).1–3 To date, tissue PD-L1 immunohistochemistry is one of the leading biomarkers for prediction of ICIs response but has several limitations.4 5Extracellular vesicles (EVs) are cell-derived structures involved in cell communication and represent a potential minimally invasive alternative to predicting ICI response.6–9 Based on this and our preliminary results presented at SITC 2020,10 we hypothesize that EV PD-L1 predicts response to ICIs in NSCLC.MethodsThis study evaluates an exploratory cohort of advanced/metastatic NSCLC patients receiving ICIs (cohort A) and a validation cohort receiving Pembrolizumab+docetaxel or docetaxel alone (PROLUNG Phase 2 randomized trial) (cohort B).11 Plasma samples were collected pre-treatment (T1) and at 3 treatment cycles (T2) (figure 1A). Response was assessed by computed-tomography scan at 3 (cohort A) and 6–8 treatment cycles (cohort B) according to mono- or chemotherapy combination therapy. Patients were classified as responders (partial, stable, or complete response) or non-responders (progressive disease) by RECISTv1.1.12 EVs were isolated by serial ultracentrifugation and characterized following ISEV recommendations.13,14 Tissue PD-L1 expression was measured by standardized immunohistochemistry (SP263, 22C3, or 28–8 clones)5 and EV PD-L1 expression by immunoblot and its ratio was calculated as EV PD-L1 T2/T1. Cut-offs from the exploratory cohort were applied to the validation cohort, being EV PD-L1 ratio <0.85 = Low.ResultsPaired samples from 30 ICIs, 23 pembrolizumab+docetaxel, and 15 docetaxel treated patients were analyzed. In cohort A, non-responders showed higher EV PD-L1 ratio than responders (p=0.012) (figure 1B) with an area-under-the-curve (AUC) of 77.3%, 83.3% sensitivity, and 61.1% specificity, while the tissue PD-L1 was not predictive (AUC=50%). As a validation, pembrolizumab+docetaxel treated non-responders showed higher EV PD-L1 ratio (p=0.036) than responders with an AUC=69.3%, sensitivity=75%, and specificity=63.6%, outperforming the tissue PD-L1 (figure 1C). No statistically significant differences were observed in the docetaxel group (p=0.885). Moreover, ICIs patients with higher EV PD-L1 ratio showed shorter progression-free survival (PFS) (HR=0.30, p=0.066) and overall survival (OS) (HR=0.17, p=0.016) (figure 1D) which was also observed in the pembrolizumab+docetaxel cohort with shorter PFS (HR=0.12, p=0.004) and OS (HR=0.23, p=0.010) (figure 1E). EV PD-L1 ratio did not predict survival in docetaxel-treated patients.Abstract 23 Figure 1(A) Study design and methodology. (B) EV PD-L1 ratio predicts response to ICIs in 30 NSCLC patients from the discovery cohort A and outperforms tissue PD-L1. (C) EV PD-L1 ratio is predictive for response to pembrolizumab+docetaxel in 23 NSCLC patients but not in 15 patients receiving docetaxel alone from cohort B. (D) Higher EV PD-L1 ratio predicts shorter PFS and OS in 30 patients from the discovery cohort A treated with ICIs. (E) Higher EV PD-L1 ratio is associated with shorter PFS and OS in 23 patients treated with pembrolizumab+docetaxel but not in patients treated with docetaxel alone. Abbreviations: CT: Computed tomography, EV: Extracellular vesicle; HR: Hazard Ratio; ICIs: Immune-checkpoint Inhibitors; IHC: Immunohistochemistry; NR: Non-Responders; OS: Overall Survival; p: p-value; PFS: Progression-free survival; R: Responders [Created with BioRender].ConclusionsWe demonstrated that treatment-associated changes in EV PD-L1 levels are predictive of response and survival in advanced NSCLC patients treated with ICIs. This model, if confirmed in a large prospective cohort, could have important clinical implications, guiding treatment decisions and improving the outcome of patients receiving ICIs.AcknowledgementsWe would like to extend our gratitude to the all the patients that participated in the study.ReferencesBorghaei H, Paz-Ares L, Horn L, Spigel DR, Steins M, Ready NE, et al. Nivolumab versus Docetaxel in Advanced Nonsquamous Non–Small-Cell Lung Cancer. N Engl J Med 2015;373:1627–39.Herbst RS, Baas P, Kim DW, Felip E, Pérez-Gracia JL, Han JY, et al. Pembrolizumab versus docetaxel for previously treated, PD-L1-positive, advanced non-small-cell lung cancer (KEYNOTE-010): A randomised controlled trial. Lancet 2016;387:1540–50.Ruiz-Patiño A, Arrieta O, Cardona AF, Martín C, Raez LE, Zatarain-Barrón ZL, et al. Immunotherapy at any line of treatment improves survival in patients with advanced metastatic non-small cell lung cancer (NSCLC) compared with chemotherapy (Quijote-CLICaP). Thorac Cancer 2020;11:353–61.Doroshow DB, Bhalla S, Beasley MB, Sholl LM, Kerr KM, Gnjatic S, et al. PD-L1 as a biomarker of response to immune-checkpoint inhibitors. Nat Rev Clin Oncol 2021;18:345–362.Hirsch FR, McElhinny A, Stanforth D, Ranger-Moore J, Jansson M, Kulangara K, et al. PD-L1 immunohistochemistry assays for lung cancer: results from phase 1 of the blueprint PD-L1 IHC assay comparison project. J Thorac Oncol 2017;12:208–222.Poggio M, Hu T, Pai CC, Chu B, Belair CD, Chang A, et al. Suppression of exosomal PD-L1 induces systemic anti-tumor immunity and memory. Cell 2019;177:414–427.e13.Cordonnier M, Nardin C, Chanteloup G, Derangere V, Algros MP, Arnould L, et al. Tracking the evolution of circulating exosomal-PD-L1 to monitor melanoma patients. J Extracell Vesicles 2020;9:1710899.Del Re M, Cucchiara F, Rofi E, Fontanelli L, Petrini I, Gri N, et al. A multiparametric approach to improve the prediction of response to immunotherapy in patients with metastatic NSCLC. Cancer Immunol Immunother 2020;70:1667–1678.Chen G, Huang AC, Zhang W, Zhang G, Wu M, Xu W, et al. Exosomal PD-L1 contributes to immunosuppression and is associated with anti-PD-1 response. Nature. 2018;560:382–6.10 de Miguel Perez D, Russo A, Gunasekaran M, Cardona A, Lapidus R, Cooper B, et al. 31 Dynamic change of PD-L1 expression on extracellular vesicles predicts response to immune-checkpoint inhibitors in non-small cell lung cancer patients. 2020J Immunother Cancer;8(Suppl 3):A30–A30.Arrieta O, Barrón F, Ramírez-Tirado LA, Zatarain-Barrón ZL, Cardona AF, Díaz-García D, et al. Efficacy and safety of pembrolizumab plus docetaxel vs docetaxel alone in patients with previously treated advanced non–small cell lung cancer: the PROLUNG phase 2 randomized clinical trial. 2020JAMA Oncol;6:856–864.Eisenhauer EA, Therasse P, Bogaerts J, Schwartz LH, Sargent D, Ford R, et al. New response evaluation criteria in solid tumours: Revised RECIST guideline (version 1.1). 2009Eur J Cancer;45:228–47.Reclusa P, Verstraelen P, Taverna S, Gunasekaran M, Pucci M, Pintelon I, et al. Improving extracellular vesicles visualization: From static to motion. 2020Sci Rep;10:6494.Théry C, Witwer KW, Aikawa E, Alcaraz MJ, Anderson JD, Andriantsitohaina R, et al. Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines. 2018J Extracell Vesicles;7:1535750Ethics ApprovalPatients consented to Institutional Review Board–approved protocol, A.O. Pappardo, Messina, Italy for cohort A and Thoracic Oncology Unit, Instituto Nacional de Cancerología (INCan), México City, México in case of the cohort B. Biological material was transferred to the University of Maryland School of Medicine, Baltimore for EV analysis under signed MTA between institutions MTA/2020–13111 & MTA/2020–13113

Genomic Landscape of Primary Resistance to Osimertinib Among Hispanic Patients with EGFR-Mutant Non-Small Cell Lung Cancer (NSCLC): Results of an Observational Longitudinal Cohort Study

Background: Epidermal growth factor receptor (EGFR) mutations (EGFRm) represent one of the most common genomic alterations identified among patients with non-small cell lung cancer (NSCLC). Several targeted agents for patients with EGFRm have been proven safe and effective, including the third-generation tyrosine kinase inhibitor (TKI) osimertinib. Nonetheless, some patients will present with or develop EGFR-TKI resistance mechanisms. Objective: We characterized the genomic landscape of primary resistance to osimertinib among Hispanic patients with EGFR-mutant NSCLC. Methods: An observational longitudinal cohort study was conducted with two groups of patients, those with intrinsic resistance (cohort A) and those with long-term survival (cohort B). All patients were treated and followed between January 2018 and May 2022. All patients were assessed for Programmed Cell Death Ligand 1 (PD-L1) expression and Bcl-2-like protein 11 (BIM)/AXL mRNA expression before starting TKI. After 8 weeks of treatment, a liquid biopsy was performed to determine the presence of circulating free DNA (cfDNA), and next-generation sequencing (NGS) was used to identify mutations at the time of progression. In both cohorts, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) were evaluated. Results: We found a homogeneous distribution of EGFR-sensitizing mutations in both cohorts. For cohort A, exon 21 mutations were more common than exon 19 deletions (ex19dels) for cohort B (P = 0.0001). The reported ORR for osimertinib was 6.3% and 100% for cohorts A and B, respectively (P = 0.0001). PFS was significantly higher in cohort B (27.4 months vs. 3.1 months; P = 0.0001) and ex19del patients versus L858R (24.5 months, 95% confidence interval [CI] 18.2-NR), vs. 7.6 months, 95% CI 4.8-21.1; P = 0.001). OS was considerably lower for cohort A (20.1 months vs. 36.0 months; P = 0.0001) and was better for patients with ex19del, no brain metastasis, and low tumor mutation burden. At the time of progression, more mutations were found in cohort A, identifying off-target alterations more frequently, including TP53, RAS, and RB1. Conclusion: EGFR-independent alterations are common among patients with primary resistance to osimertinib and significantly impact PFS and OS. Our results suggest that among Hispanic patients, other variables associated with intrinsic resistance include the number of commutations, high levels AXL mRNA, and low levels of BIM mRNA, T790M de novo, EGFR p.L858R presence, and a high tumoral mutational burden

Low-molecular-weight or Unfractionated Heparin in Venous Thromboembolism: The Influence of Renal Function

BACKGROUND: In patients with acute venous thromboembolism and renal insufficiency, initial therapy with unfractionated heparin may have some advantages over low-molecular-weight heparin. METHODS: We used the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) Registry data to evaluate the 15-day outcome in 38,531 recruited patients. We used propensity score matching to compare patients treated with unfractionated heparin with those treated with low-molecular-weight heparin in 3 groups stratified by creatinine clearance levels at baseline: >60 mL/min, 30 to 60 mL/min, or <30 mL/min. RESULTS: Patients initially receiving unfractionated heparin therapy (n = 2167) more likely had underlying diseases than those receiving low-molecular-weight heparin (n = 34,665). Propensity score-matched groups of patients with creatinine clearance levels >60 mL/min (n = 1598 matched pairs), 30 to 60 mL/min (n = 277 matched pairs), and <30 mL/min (n = 210 matched pairs) showed an increased 15-day mortality for unfractionated heparin compared with low-molecular-weight heparin (4.5% vs 2.4% [P = .001], 5.4% vs 5.8% [P = not significant], and 15% vs 8.1% [P = .02], respectively), an increased rate of fatal pulmonary embolism (2.8% vs 1.2% [P = .001], 3.2% vs 2.5% [P = not significant], and 5.7% vs 2.4% [P = .02], respectively), and a similar rate of fatal bleeding (0.3% vs 0.3%, 0.7% vs 0.7%, and 0.5% vs 0.0%, respectively). Multivariate analysis confirmed that patients treated with unfractionated heparin were at increased risk for all-cause death (odds ratio, 1.8; 95% confidence interval, 1.3-2.4) and fatal pulmonary embolism (odds ratio, 2.3; 95% confidence interval, 1.5-3.6). CONCLUSIONS: In comparison with low-molecular-weight heparin, initial therapy with unfractionated heparin was associated with a higher mortality and higher rate of fatal pulmonary embolism in patients with creatinine clearance levels >60 mL/min or <30 mL/min, but not in those with levels between 30 and 60 mL/min

Platelet count and outcome in patients with acute venous thromboembolism.

The relationship between platelet count and outcome in patients with acute venous thromboembolism (VTE) has not been consistently explored. RIETE is an ongoing registry of consecutive patients with acute VTE. We categorised patients as having very low- (&lt;80,000/µl), low- (80,000/µl to 150,000/µl), normal- (150,000/µl to 300,000/µl), high- (300,000/µl to 450,000/µl), or very high (&gt;450,000/µl) platelet count at baseline, and compared their three-month outcome. As of October 2012, 43,078 patients had been enrolled in RIETE: 21,319 presenting with pulmonary embolism and 21,759 with deep-vein thrombosis. In all, 502 patients (1.2%) had very low-; 5,472 (13%) low-; 28,386 (66%) normal-; 7,157 (17%) high-; and 1,561 (3.6%) very high platelet count. During the three-month study period, the recurrence rate was: 2.8%, 2.2%, 1.8%, 2.1% and 2.2%, respectively; the rate of major bleeding: 5.8%, 2.6%, 1.7%, 2.3% and 4.6%, respectively; the rate of fatal bleeding: 2.0%, 0.9%, 0.3%, 0.5% and 1.2%, respectively; and the mortality rate: 29%, 11%, 6.5%, 8.8% and 14%, respectively. On multivariate analysis, patients with very low-, low-, high- or very high platelet count had an increased risk for major bleeding (odds ratio [OR]: 2.70, 95% confidence interval [CI]: 1.85-3.95; 1.43 [1.18-1.72]; 1.23 [1.03-1.47]; and 2.13 [1.65-2.75]) and fatal bleeding (OR: 3.70 [1.92-7.16], 2.10 [1.48-2.97], 1.29 [0.88-1.90] and 2.49 [1.49-4.15]) compared with those with normal count. In conclusion, we found a U-shaped relationship between platelet count and the three-month rate of major bleeding and fatal bleeding in patients with VTE

Influence of recent immobilization or surgery on mortality in cancer patients with venous thromboembolism

BACKGROUND: The influence of recent immobilization or surgery on mortality in cancer patients with venous thromboembolism (VTE) has not been thoroughly studied. METHODS: We used the RIETE Registry data to compare the 3-month mortality rate in cancer patients with VTE, with patients categorized according to the presence of recent immobilization, surgery or neither. The major outcomes were fatal pulmonary embolism (PE) and fatal bleeding within the first 3 months. RESULTS: Of 6,746 patients with active cancer and acute VTE, 1,224 (18%) had recent immobilization, 1,055 (16%) recent surgery, and 4,467 (66%) had neither. The all-cause mortality was 23.4% (95% CI: 22.4-24.5), and the PE-related mortality: 2.5% (95% CI: 2.1-2.9). Four in every ten patients dying of PE had recent immobilization (37%) or surgery (5.4%). Only 28% of patients with immobilization had received prophylaxis, as compared with 67% of the surgical. Fatal PE was more common in patients with recent immobilization (5.0%; 95% CI: 3.9-6.3) than in those with surgery (0.8%; 95% CI: 0.4-1.6) or neither (2.2%; 95% CI: 1.8-2.6). On multivariate analysis, patients with immobilization were at an increased risk for fatal PE (odds ratio: 1.8; 95% CI: 1.2-2.5). CONCLUSIONS: One in every three cancer patients dying of PE had recent immobilization for ≥ 4 days. Many of these deaths could have been prevented with adequate thromboprophylaxis

Symptomatic subsegmental versus more central pulmonary embolism: Clinical outcomes during anticoagulation

Background: The optimal therapy of patients with acute subsegmental pulmonary embolism (PE) is controversial. Methods: We used the RIETE (Registro Informatizado Enfermedad TromboEmb\uf3lica) database to compare the rate of symptomatic PE recurrences during anticoagulation in patients with subsegmental, segmental, or more central PEs. Results: Among 15&nbsp;963 patients with a first episode of symptomatic PE, 834 (5.2%) had subsegmental PE, 3797 (24%) segmental, and 11&nbsp;332 (71%) more central PE. Most patients in all subgroups received initial therapy with low-molecular-weight heparin, and then most switched to vitamin K antagonists. Median duration of therapy was 179, 185, and 204&nbsp;days, respectively. During anticoagulation, 183 patients developed PE recurrences, 131 developed deep vein thrombosis (DVT), 543 bled, and 1718 died (fatal PE, 135). The rate of PE recurrences was twofold higher in patients with subsegmental PE than in those with segmental (hazard ratio [HR], 2.13; 95% confidence interval [CI], 1.16-3.85) or more central PE (HR, 1.89; 95% CI, 1.12-3.13). On multivariable analysis, patients with subsegmental PE had a higher risk for PE recurrences than those with central PE (adjusted HR, 1.75; 95% CI, 1.02-3.03). After stratifying patients with subsegmental PE according to ultrasound imaging in the lower limbs, the rate of PE recurrences was similar in patients with DVT, in patients without DVT, and in those with no ultrasound imaging. Conclusions: Our study reveals that the risk for PE recurrences in patients with segmental PE is not lower than in those with more central PE, thus suggesting that the risk of PE recurrences is not influenced by the anatomic location of PE

Validation of a score for predicting fatal bleeding in patients receiving anticoagulation for venous thromboembolism

BACKGROUND: The only available score to assess the risk for fatal bleeding in patients with venous thromboembolism (VTE) has not been validated yet. METHODS: We used the RIETE database to validate the risk-score for fatal bleeding within the first 3 months of anticoagulation in a new cohort of patients recruited after the end of the former study. Accuracy was measured using the ROC curve analysis. RESULTS: As of December 2011, 39,284 patients were recruited in RIETE. Of these, 15,206 had not been included in the former study, and were considered to validate the score. Within the first 3 months of anticoagulation, 52 patients (0.34%; 95% CI: 0.27-0.45) died of bleeding. Patients with a risk score of 4 points had a rate of 1.44%. The c-statistic for fatal bleeding was 0.775 (95% CI 0.720-0.830). The score performed better for predicting gastrointestinal (c-statistic, 0.869; 95% CI: 0.810-0.928) than intracranial (c-statistic, 0.687; 95% CI: 0.568-0.806) fatal bleeding. The score value with highest combined sensitivity and specificity was 1.75. The risk for fatal bleeding was significantly increased (odds ratio: 7.6; 95% CI 3.7-16.2) above this cut-off value. CONCLUSIONS: The accuracy of the score in this validation cohort was similar to the accuracy found in the index study. Interestingly, it performed better for predicting gastrointestinal than intracranial fatal bleeding

Heart Rate and Mortality in Patients With Acute Symptomatic Pulmonary Embolism

International audienc