Durvalumab Combined With Pemetrexed-Based Chemotherapy in Trial-Ineligible Patients With Mesothelioma: A Brief Report

Introduction: Chemoimmunotherapy is associated with promising activity in mesothelioma in phase II to III trials. Studies exploring this approach in patients ineligible for clinical trials are lacking. We assembled a cohort of patients receiving pemetrexed-based chemotherapy with durvalumab outside of clinical trials. Methods: Patients with pleural mesothelioma received pemetrexed plus durvalumab or carboplatin plus pemetrexed plus durvalumab via off-label authorization at Massachusetts General Hospital. Response to chemoimmunotherapy was assessed per modified Response Evaluation Criteria in Solid Tumors version 1.1. A retrospective chart review was conducted to assess safety per Common Terminology Criteria for Adverse Events version 5.0. Results: Twelve patients were included in the series. Nine patients were treated with triplet chemoimmunotherapy. Three patients received doublet chemoimmunotherapy because of platinum ineligibility. Concurrent active malignancies and symptomatic cardiac disease were present in three patients (25%) and two patients (17%), respectively. Ten patients had measurable disease at baseline. With the triplet regimen, partial responses were observed in four of the seven (57%) patients with measurable disease. All three patients receiving pemetrexed plus durvalumab had measurable disease and experienced a partial response. Primary progression was not observed with either regimen. Overall, eight patients (75%) remained on treatment for more than 6 months without progression. Five patients developed immune-related adverse events (n = 1 each pyrexia, arthritis, neutropenia, Raynaud’s disease, stomatitis). Three patients discontinued treatment because of toxicity or symptomatic comorbid conditions (n = 1 grade 3 heart failure, n = 1 grade 2 fever + progressive kidney cancer, n = 1 grade 2 fatigue). Conclusions: Antitumor activity of chemoimmunotherapy reported in phase II to III clinical trials is generalizable to the broader patient population with mesothelioma. However, the tolerability of chemoimmunotherapy is impacted by comorbid conditions in real-world patients

Efficacy and Safety of Dose-Escalated Alectinib in Patients With Metastatic ALK-Positive NSCLC and Central Nervous System Relapse on Standard-Dose Alectinib

Introduction: Central nervous system (CNS) metastases remain a common challenge in patients with ALK-positive NSCLC. We previously reported reinduction of CNS responses using dose-intensified alectinib in two patients with CNS progression on standard-dose alectinib. Nevertheless, this strategy has not been assessed in larger cohorts. Methods: Patients were eligible for this retrospective study if they had metastatic ALK-positive NSCLC with CNS relapse on alectinib 600 mg twice daily dosing and subsequently received escalated dosing (900 mg twice daily) of alectinib. CNS efficacy was assessed per the modified Response Evaluation Criteria in Solid Tumors version 1.1. Results: Among 27 patients, median duration of dose-escalated alectinib was 7.7 months (95% confidence interval [CI]: 4.8–10.9), with median overall time-to-progression (TTP) of 7.1 months (95% CI: 4.4–9.6). Among 25 CNS response-assessable patients, CNS objective response rate was 12.0% (95% CI: 2.5–31.2) and CNS disease control rate was 92.0% (95% CI: 74.0–99.0), with median CNS duration of disease control of 5.3 months (95% CI: 3.4–8.3) and median CNS TTP of 7.1 months (95% CI: 4.4–9.6). Among four patients with measurable CNS disease at baseline, three experienced a best intracranial response of stable disease and one experienced intracranial partial response with CNS TTP ranging from 4.1 to 7.7 months. No patient required drug discontinuation due to treatment-related adverse event or experienced grade 3 or higher treatment-related adverse events. Conclusions: Dose-intensified alectinib was found to have tolerability and activity in patients with ALK-positive NSCLC who experienced CNS relapse on standard-dose alectinib and represents one clinically viable strategy for this population

Efficacy and Tolerability of ALK/MET Combinations in Patients With ALK-Rearranged Lung Cancer With Acquired MET Amplification: A Retrospective Analysis

Introduction: MET amplification is a potentially actionable resistance mechanism in ALK-rearranged (ALK+) lung cancer. Studies describing treatment outcomes of this molecular subgroup are lacking. Methods: We assembled a cohort of patients with ALK+ lung cancer and acquired MET amplification (identified by tissue or plasma) who received regimens targeting both ALK and MET. Efficacy and safety were assessed using the Response Evaluation Criteria in Solid Tumors version 1.1 and Common Terminology Criteria for Adverse Events version 4.03, respectively. Results: A total of 12 patients were included in the series. MET amplification was detected after a median of 1.5 (range 1–5) lines of therapy. Four distinct regimens were implemented to address MET amplification: crizotinib (n = 2), lorlatinib plus crizotinib (n = 6), alectinib plus capmatinib (n = 3), and alectinib plus crizotinib (n = 1). Partial responses were observed in five (42%) of 12 patients, including patients who received crizotinib (n = one of two), lorlatinib plus crizotinib (n = three of six), and alectinib plus capmatinib (n = one of three). Primary progression was observed in four patients (33%). Grades 1 to 2 peripheral edema, occurring in seven (58%) patients, was found with both crizotinib and capmatinib. One patient required dose reduction of capmatinib plus alectinib for persistent grade 2 edema. Across the regimens, one patient discontinued therapy for toxicity, specifically neurocognitive toxicity from lorlatinib plus crizotinib. At progression on ALK+ MET therapy, potential resistance mechanisms included MET copy number changes and ALK kinase domain mutations. Conclusions: Combined ALK and MET inhibition is associated with moderate antitumor activity in patients with ALK+ NSCLC with concurrent MET amplification. Prospective studies are indicated to confirm activity and identify individuals most likely to benefit from the treatment

Response to Immune Checkpoint Inhibition as Monotherapy or in Combination With Chemotherapy in Metastatic ROS1-Rearranged Lung Cancers

Introduction: ROS1 fusions are oncogenic drivers in 1% to 3% of NSCLCs. The activity of immune checkpoint inhibitor (ICI) monotherapy or in combination with chemotherapy (chemotherapy with ICI [chemo-ICI]) in these tumors and their immunophenotype have not been systematically described. Methods: In this multi-institutional retrospective study, tumor programmed death-ligand 1 (PD-L1) expression and tumor mutational burden (TMB) were evaluated in patients with ROS1-rearranged NSCLC. Time-to-treatment discontinuation (TTD) and objective response rate (ORR) (Response Evaluation Criteria in Solid Tumors [RECIST] version 1.1) were calculated for patients treated with ICI or chemo-ICI in the metastatic setting. Results: A total of 184 patients were identified. Among 146 assessable cases, PD-L1 expression was less than 1% in 60 (41%), 1% to 49% in 35 (24%), and greater than or equal to 50% in 51 tumors (35%). Of 100 (92%) TMB-assessable tumors, 92 had less than 10 mutations per megabase. TMB was significantly lower for ROS1-rearranged tumors (n = 97) compared with tumors with EGFR (n = 1250) or KRAS alterations (n = 1653) and all other NSCLC tumors (n = 2753) evaluated with Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (median TMB = 2.6 versus 3.5, 7.0, and 6.1 mutations per megabase, p < 0.001). Among patients treated with ICI, median TTD was 2.1 months (95% confidence interval [CI]: 1.0–4.2 mo; n = 28) and ORR 13% (2 of 16 RECIST-assessable; 95% CI: 2%–38%). Among patients treated with chemo-ICI, median TTD was 10 months (95% CI: 4.7–14.1 mo; n = 11) and ORR 83% (5 of 6 RECIST-assessable; 95% CI: 36%–100%). There was no difference in PD-L1 expression (p = 0.91) or TMB (p = 0.83) between responders and nonresponders. Conclusions: Most ROS1-rearranged NSCLCs have low PD-L1 expression and TMB. The activity of ICI in these tumors is modest. In contrast, chemo-ICI can achieve meaningful activity

Osimertinib in NSCLC With Atypical EGFR-Activating Mutations: A Retrospective Multicenter Study

Introduction: EGFR mutations drive a subset of NSCLC. Patients harboring the common EGFR mutations, deletion of exon 19 and L858R, respond well to osimertinib, a third-generation tyrosine kinase inhibitor. Nevertheless, the effect of osimertinib on NSCLC with atypical EGFR mutations is not well described. This multicenter retrospective study evaluates the efficacy of osimertinib among patients with NSCLC harboring atypical EGFR mutations. Methods: Patients with metastatic NSCLC treated with osimertinib, harboring at least one atypical EGFR mutation, excluding concurrent deletion of exon 19, L858R, or T790M mutations, from six U.S. academic cancer centers were included. Baseline clinical characteristics were collected. The primary end point was the time to treatment discontinuation (TTD) of osimertinib. Objective response rate by the Response Evaluation Criteria in Solid Tumors version 1.1 was also assessed. Results: A total of 50 patients with NSCLC with uncommon EGFR mutations were identified. The most frequent EGFR mutations were L861Q (40%, n = 18), G719X (28%, n = 14), and exon 20 insertion (14%, n = 7). The median TTD of osimertinib was 9.7 months (95% confidence interval [CI]: 6.5–12.9 mo) overall and 10.7 months (95% CI: 3.2–18.1 mo) in the first-line setting (n = 20). The objective response rate was 31.7% (95% CI: 18.1%–48.1%) overall and 41.2% (95% CI: 18.4%–67.1%) in the first-line setting. The median TTD varied among patients with L861Q (17.2 mo), G719X (7.8 mo), and exon 20 insertion (1.5 mo) mutations. Conclusions: Osimertinib has activity in patients with NSCLC harboring atypical EGFR mutations. Osimertinib activity differs by the type of atypical EGFR-activating mutation

Arsenic exposure is associated with elevated sweat chloride concentration and airflow obstruction among adults in Bangladesh: A cross-sectional study.

Arsenic is associated with lung disease and experimental models suggest that arsenic-induced degradation of the chloride channel CFTR (cystic fibrosis transmembrane conductance regulator) is a mechanism of arsenic toxicity. We examined associations between arsenic exposure, sweat chloride concentration (measure of CFTR function), and pulmonary function among 269 adults in Bangladesh. Participants with sweat chloride ≥ 60 mmol/L had higher arsenic exposures than those with sweat chloride < 60 mmol/L (water: median 77.5 µg/L versus 34.0 µg/L, p = 0.025; toenails: median 4.8 µg/g versus 3.7 µg/g, p = 0.024). In linear regression models, a one-unit µg/g increment in toenail arsenic was associated with a 0.59 mmol/L higher sweat chloride concentration, p < 0.001. Among the entire study population, after adjusting for covariates including age, sex, smoking, education, and height, toenail arsenic concentration was associated with increased odds of airway obstruction (OR: 1.97, 95%: 1.06, 3.67, p = 0.03); however, sweat chloride concentration did not mediate this association. Our findings suggest that sweat chloride concentration may serve as novel biomarker for arsenic exposure, warranting further investigation in diverse populations, and that arsenic likely acts on the lung through mechanisms other than inducing CFTR dysfunction. Alternative mechanisms by which environmental arsenic exposure may lead to obstructive lung disease, such as arsenic-induced direct lung injury and/or increase lung proteinase activity, require additional exploration in future work