Efficacy and safety of nivolumab for patients with pre-treated type B3 thymoma and thymic carcinoma: results from the EORTC-ETOP NIVOTHYM phase II trial.

BACKGROUND: Thymic malignancies are rare intrathoracic tumors, which may be aggressive and difficult to treat. They represent a therapeutic challenge in the advanced/metastatic setting, with limited treatment options after the failure of first-line platinum-based chemotherapy. They are frequently associated with autoimmune disorders that also impact oncological management. MATERIALS AND METHODS: NIVOTHYM is an international, multicenter, phase II, two-cohort, single-arm trial evaluating the activity and safety of nivolumab [240 mg intravenously (i.v.) q2 weeks] alone or with ipilimumab (1 mg /kg i.v. q6 weeks) in patients with advanced/relapsed type B3 thymoma or thymic carcinoma, after exposure to platinum-based chemotherapy. The primary endpoint is progression-free survival rate at 6 months (PFSR-6) based on RECIST 1.1 as per independent radiological review. RESULTS: From April 2018 to February 2020, 55 patients were enrolled in 15 centers from 5 countries. Ten patients (18%) had type B3 thymoma and 43 (78%) had thymic carcinoma. The majority were male (64%), and the median age was 58 years. Among the 49 eligible patients who started treatment, PFSR-6 by central review was 35% [95% confidence interval (CI) 22% to 50%]. The overall response rate and disease control rate were 12% (95% CI 5% to 25%) and 63% (95% CI 48% to 77%), respectively. Using the Kaplan-Meier method, median progression-free survival and overall survival by local assessment were 6.0 (95% CI 3.1-10.4) months and 21.3 (95% CI 11.6-not estimable) months, respectively. In the safety population of 54 patients, adverse events (AEs) of grade 1/2 were observed in 22 (41%) patients and grade 3/4 in 31 (57%) patients. Treatment-related AEs of grade 4 included one case of neutropenia, one case of immune-mediated transaminitis, and two cases of myocarditis. CONCLUSIONS: Nivolumab monotherapy demonstrated an acceptable safety profile and objective activity, although it has been insufficient to meet its primary objective. The second cohort of NIVOTHYM is currently ongoing to assess the combination of nivolumab plus ipilimumab.

Spatially resolved proteomic profiling identifies tumor cell CD44 as a biomarker associated with sensitivity to PD-1 axis blockade in advanced non-small-cell lung cancer.

BACKGROUND: Most patients with advanced non-small-cell lung cancer (NSCLC) fail to derive significant benefit from programmed cell death protein-1 (PD-1) axis blockade, and new biomarkers of response are needed. In this study, we aimed to discover and validate spatially resolved protein markers associated with sensitivity to PD-1 axis inhibition in NSCLC. METHODS: We initially assessed a discovery cohort of 56 patients with NSCLC treated with PD-1 axis inhibitors at Yale Cancer Center. Using the GeoMx Digital Spatial Profiling (DSP) system, 71 proteins were measured in spatial context on each spot in a tissue microarray. We used the AQUA method of quantitative immunofluorescence (QIF) to orthogonally validate candidate biomarkers. For external independent validation, we assessed whole tissue sections derived from 128 patients with NSCLC treated with single-agent PD-1 axis inhibitors at the 12 de Octubre Hospital (Madrid) using DSP. We further analyzed two immunotherapy untreated cohorts to address prognostic significance (n=252 from Yale Cancer Center; n=124 from University Clinic of Navarra) using QIF and DSP, respectively. RESULTS: Using continuous log-scaled data, we identified CD44 expression in the tumor compartment (pan-cytokeratin (CK)+) as a novel predictor of prolonged progression-free survival (PFS) (multivariate HR=0.68, p=0.043) in the discovery set. We validated by QIF that tumor CD44 levels assessed as continuous QIF scores were associated with longer PFS (multivariate HR=0.31, p=0.022) and overall survival (multivariate HR=0.29, p=0.038). Using DSP in an independent immunotherapy treated cohort, we validated that CD44 levels in the tumor compartment, but not in the immune compartment (panCK-/CD45+), were associated with clinical benefit (OR=1.22, p=0.018) and extended PFS under PD-1 axis inhibition using the highest tertile cutpoint (multivariate HR=0.62, p=0.03). The effect of tumor cell CD44 in predicting PFS remained significant after correcting for programmed death-ligand 1 (PD-L1) Tumor Proportion Score (TPS) in both cohorts. High tumor cell CD44 was not prognostic in the absence of immunotherapy. Using DSP data, intratumoral regions with elevated tumor cell CD44 expression showed prominent (fold change>1.5, adjusted p<0.05) upregulation of PD-L1, TIM-3, ICOS, and CD40 in two independent cohorts. CONCLUSIONS: This work highlights CD44 as a novel indicative biomarker of sensitivity to PD-1 axis blockade that might help to improve immunotherapy strategies for NSCLC.

RELAY, ramucirumab plus erlotinib versus placebo plus erlotinib in patients with untreated, EGFR-mutated, metastatic non-small cell lung cancer: Europe/United States subset analysis.

BACKGROUND: In EGFR mutation-positive NSCLC, dual EGFR/VEGFR inhibition compared to EGFR alone increases anti-tumor efficacy. The Phase III RELAY trial demonstrated superior PFS for ramucirumab plus erlotinib (RAM + ERL) over placebo plus erlotinib (PBO + ERL) (HR 0.591 [95% CI 0.461-0.760], p<0.0001). EGFR mutated NSCLC is less prevalent in Western versus Asian patients. This prespecified analysis evaluates efficacy and safety of RAM + ERL in EU and US patients enrolled in RELAY. PATIENTS AND METHODS: Patients were randomized 1:1 to ERL + RAM (10 mg/kg IV) or PBO Q2W. Treatment continued until unacceptable toxicity or progressive disease. Patients were stratified by geographic region (East Asia vs "other" [EU/US and Canada (EU/US)]). Objectives included PFS, ORR, DoR, OS, PFS2, safety and biomarker analysis. RESULTS: EU/US subset included 113/449 (25.9%) patients (58 RAM + ERL, 55 PBO + ERL). RAM + ERL improved PFS (20.6 vs 10.9 months, HR 0.605 [95% CI: 0.362-1.010]). ORR and DCR were similar, but median DoR was longer with RAM + ERL (18.0 vs 10.1 months, HR 0.527 [95% CI: 0.296-0.939]). OS and PFS2 were immature at data cut-off (censoring rates 81.0-81.8% and 67.3-79.3%, respectively). Most commonly reported Grade ≥3 TEAE for RAM + ERL was hypertension (17 [29.8%]) and for PBO + ERL, dermatitis acneiform (5 [9.1%]). CONCLUSION: EU/US subset analysis showed improved efficacy outcomes for RAM + ERL and a safety profile consistent with the overall population. Ramucirumab is a safe and effective addition to standard-of-care EGFR-TKI for EGFR mutation-positive metastatic NSCLC.

Analysis of mismatch repair (MMR) proteins expression in a series of malignant pleural mesothelioma (MPM) patients.

BACKGROUND: Promising results have been reported with immune checkpoint inhibitors (ICI) in a small proportion of MPM patients. MMR deficiency (dMMR) has been well described in several malignancies and was approved as a biomarker for anti-PD-1 inhibitors. Next generation sequencing (NGS) data demonstrated that 2% of MPM harbor microsatellite instability. The aim of this study is to characterize MMR by immunohistochemistry (IHC) in a series of MPM including a subset of patients treated with immunotherapy. METHODS: Tumors of 159 MPM p diagnosed between 2002 and 2017 were reviewed. Formalin-fixed, paraffin-embedded tissue was stained for MLH1, MSH2, MSH6 and PMS2 and tumors were classified as dMMR (MMR protein expression negative) and MMR intact (all MMR proteins positively expressed). We retrospectively collected clinical outcomes under standard chemotherapy and experimental immunotherapy in the entire cohort. RESULTS: MMR protein expression was analyzed in 158 samples with enough tissue and was positive in all of the cases. Twenty two patients received ICI with anti-CTLA4 or anti-PD-1 blockade in clinical trials, 58% had a response or stable disease for more than 6 m, with median progression-free survival (PFS) of 5.7 m (2.1-26.1 m). The median overall survival (mOS) in all population was 15 months (m) (13.5-18.8 m). In a multivariable model factors associated to improved mOS were PS 0, neutrophil-lymphocyte ratio (NLR) < 5 and epithelioid histology (p < 0.001). CONCLUSIONS: In our series we were unable to identify any MPM patient with dMMR by IHC. Further studies are needed to elucidate potential predictive biomarkers of ICI benefit in MPM.

Clinical utility of plasma-based digital next-generation sequencing in patients with advance-stage lung adenocarcinomas with insufficient tumor samples for tissue genotyping.

BACKGROUND: Approximately 30% of tumor biopsies from patients with advanced-stage lung adenocarcinomas yield insufficient tissue for successful molecular subtyping. We have analyzed the clinical utility of next-generation sequencing (NGS) of cell-free circulating tumor DNA (ctDNA) in patients with inadequate tumor samples for tissue genotyping. PATIENTS AND METHODS: We conducted the study in a multi-institutional prospective cohort of clinically unselected patients with advanced-stage lung adenocarcinomas with insufficient tissue for EGFR, ALK or ROS1 genotyping across 12 Spanish institutions (n = 93). ctDNA NGS was carried out by Guardant Health (Guardant360, Redwood City, CA), using a hybrid-capture-based 73-gene panel. Variants were deemed actionable if they were part of the OncoKB precision oncology knowledge database and classified in four levels of actionability based on their clinical or preclinical evidence for drug response. RESULTS: Eighty-three out of 93 patients (89%) had detectable levels of ctDNA. Potentially actionable level 1-4 genomic alterations were detected in 53 cases (57%), of which 13 (14%) had level 1-2A alterations (Food and Drug Administration-approved and standard-care biomarkers according to lung cancer guidelines). Frequencies of each genomic alteration in ctDNA were consistent with those observed in unselected pulmonary adenocarcinomas. The majority of the patients (62%), particularly those with actionable alterations (87%), had more than one pathogenic variant in ctDNA. The median turnaround time to genomic results was 13 days. Twelve patients (13%) received genotype-matched therapies based on ctDNA results, deriving the expected clinical benefit. Patients with co-occurring pathogenic alterations had a significantly shorter median overall survival as compared with patients without co-occurring pathogenic alteration (multivariate hazard ratio = 5.35, P = 0.01). CONCLUSION: Digital NGS of ctDNA in lung cancers with insufficient tumor samples for tissue sequencing detects actionable variants that frequently co-occur with other potentially clinically relevant genomic alterations, allowing timely initiation of genotype-matched therapies.

Immunotherapeutic maintenance treatment with toll-like receptor 9 agonist lefitolimod in patients with extensive-stage small-cell lung cancer: results from the exploratory, controlled, randomized, international phase II IMPULSE study.

Background: The immune surveillance reactivator lefitolimod (MGN1703), a DNA-based TLR9 agonist, might foster innate and adaptive immune response and thus improve immune-mediated control of residual cancer disease. The IMPULSE phase II study evaluated the efficacy and safety of lefitolimod as maintenance treatment in extensive-stage small-cell lung cancer (ES-SCLC) after objective response to first-line chemotherapy, an indication with a high unmet medical need and stagnant treatment improvement in the last decades. Patients and methods: 103 patients with ES-SCLC and objective tumor response (as per RECIST 1.1) following four cycles of platinum-based first-line induction therapy were randomized to receive either lefitolimod maintenance therapy or local standard of care at a ratio of 3 : 2 until progression or unacceptable toxicity. Results: From 103 patients enrolled, 62 were randomized to lefitolimod, 41 to the control arm. Patient demographics and response patterns to first-line therapy were balanced. Lefitolimod exhibited a favorable safety profile and pharmacodynamic assessment confirmed the mode-of-action showing a clear activation of monocytes and production of interferon-gamma-induced protein 10 (IP-10). While in the intent-to-treat (ITT) population no relevant effect of lefitolimod on progression-free and overall survival (OS) could be observed, two predefined patient subgroups indicated promising results, favoring lefitolimod with respect to OS: in patients with a low frequency of activated CD86+ B cells (hazard ratio, HR 0.53, 95% CI: 0.26-1.08; n = 38 of 88 analyzed) and in patients with reported chronic obstructive pulmonary disease (COPD) (HR 0.48, 95% CI: 0.20-1.17, n = 25 of 103). Conclusions: The IMPULSE study showed no relevant effect of lefitolimod on the main efficacy end point OS in the ITT, but (1) the expected pharmacodynamic response to lefitolimod, (2) positive OS efficacy signals in two predefined subgroups and (3) a favorable safety profile. These data support further exploration of lefitolimod in SCLC.

Analysis of expression of PTEN/PI3K pathway and programmed cell death ligand 1 (PD-L1) in malignant pleural mesothelioma (MPM).

BACKGROUND: Malignant pleural mesothelioma (MPM) frequently express elevated AKT/mTOR activity. Previous reports in gliomas, colon, breast and prostate cancer suggest that PTEN/PI3K pathway may be important for the induction of PD-L1 expression. This study explored the expression of PTEN/PI3K pathway and PD-L1 in MPM and its relationship with the patient́s prognosis MATERIAL AND METHODS: Twenty seven consecutive MPM patients were reviewed. Formalin-fixed, paraffin-embedded tissue biopsies were used for immunohistochemical analysis of PTEN/PI3K pathway and PD-L1 RESULTS: Expression of PTEN, mTOR, pAKT, p4EBP1, peif4E, pS6 and FOXO3a was found in 88.5%, 92.3%, 78.3%, 38.5%, 100%, 52.2% and 100% of tumors and PD-L1 in 23%. We found a significant correlation between pAKT, FOXO3a and PD-L1 expression and longer overall survival (p <0.05). We did not identify significant association between the level of PD-L1 expression and alterations in PI3K pathway CONCLUSIONS: This study shows PTEN/PI3K pathway and PD-L1 in MPM are frequently activated. Our results suggests that there is not association between PD-L1 and the involvement of the PI3K pathway in MPM.