Consolidation Durvalumab Should Not Be Administered to Patients With Stage III EGFR-Mutant NSCLC

Tumor Microenvironment Landscape of NSCLC Reveals Resistance Mechanisms for Programmed Death-Ligand 1 Blockade After Chemoradiotherapy: A Multicenter Prospective Biomarker Study (WJOG11518L:SUBMARINE)

INTRODUCTION

The PACIFIC regimen of consolidation therapy with the programmed cell death-ligand 1 inhibitor durvalumab after definitive concurrent chemoradiation therapy has become a standard of care for individuals with unresectable stage III NSCLC. Nevertheless, approximately half of the treated patients experience disease progression within 1 year, with the mechanisms of treatment resistance being poorly understood. We here performed a nationwide prospective biomarker study to explore the resistance mechanisms (WJOG11518L:SUBMARINE).

METHODS

A total of 135 patients with unresectable stage III NSCLC who received the PACIFIC regimen were included for comprehensive profiling of the tumor microenvironment by immunohistochemistry, transcriptome analysis, and genomic sequencing of pretreatment tumor tissue and flow cytometric analysis of circulating immune cells. Progression-free survival was compared on the basis of these biomarkers.

RESULTS

The importance of preexisting effective adaptive immunity in tumors was revealed for treatment benefit regardless of genomic features. We also identified CD73 expression by cancer cells as a mechanism of resistance to the PACIFIC regimen. Multivariable analysis of immunohistochemistry data with key clinical factors as covariables indicated that low CD8+ tumor-infiltrating lymphocyte density and the high CD73+ cancer cells were independently associated with poor durvalumab outcome (hazard ratios = 4.05 [95% confidence interval: 1.17-14.04] for CD8+ tumor-infiltrating lymphocytes; 4.79 [95% confidence interval: 1.12-20.58] for CD73). In addition, whole-exome sequencing of paired tumor samples suggested that cancer cells eventually escaped immune pressure as a result of neoantigen plasticity.

CONCLUSIONS

Our study emphasizes the importance of functional adaptive immunity in stage III NSCLC and implicates CD73 as a promising treatment target, thus providing insight forming a basis for development of a new treatment approach in NSCLC.

Radiation combined with immune checkpoint inhibitors for unresectable locally advanced non-small cell lung cancer: synergistic mechanisms, current state, challenges, and orientations

Until the advent of immune checkpoint inhibitors (ICIs), definitive radiotherapy (RT) concurrently with chemotherapy was recommended for unresectable, locally advanced non-small cell lung cancer (LA-NSCLC). The trimodality paradigm with consolidation ICIs following definitive concurrent chemoradiotherapy has been the standard of care since the PACIFIC trial. Preclinical evidence has demonstrated the role of RT in the cancer-immune cycle and the synergistic effect of RT combined with ICIs (iRT). However, RT exerts a double-edged effect on immunity and the combination strategy still could be optimized in many areas. In the context of LA-NSCLC, optimized RT modality, choice, timing, and duration of ICIs, care for oncogenic addicted tumors, patient selection, and novel combination strategies require further investigation. Targeting these blind spots, novel approaches are being investigated to cross the borders of PACIFIC. We discussed the development history of iRT and summarized the updated rationale for the synergistic effect. We then summarized the available research data on the efficacy and toxicity of iRT in LA-NSCLC for cross-trial comparisons to eliminate barriers. Progression during and after ICIs consolidation therapy has been regarded as a distinct resistance scenario from primary or secondary resistance to ICIs, the subsequent management of which has also been discussed. Finally, based on unmet needs, we probed into the challenges, strategies, and auspicious orientations to optimize iRT in LA-NSCLC. In this review, we focus on the underlying mechanisms and recent advances of iRT with an emphasis on future challenges and directions that warrant further investigation. Taken together, iRT is a proven and potential strategy in LA-NSCLC, with multiple promising approaches to further improve the efficacy. Video Abstract.

A Propensity-Matched Retrospective Comparative Study with Historical Control to Determine the Real-World Effectiveness of Durvalumab after Concurrent Chemoradiotherapy in Unresectable Stage III Non-Small Cell Lung Cancer

This study aimed to add real-world evidence to the literature regarding the effectiveness and safety of durvalumab consolidation (DC) after concurrent chemoradiotherapy (CCRT) in the treatment of unresectable stage III non-small cell lung cancer (NSCLC). Using a hospital-based NSCLC patient registry and propensity score matching in a 2:1 ratio, we conducted a retrospective cohort study of patients with unresectable stage III NSCLC who completed CCRT with and without DC. The co-primary endpoints were 2-year progression-free survival and overall survival. For the safety evaluation, we evaluated the risk of any adverse events requiring systemic antibiotics or steroids. Of 386 eligible patients, 222 patients-including 74 in the DC group-were included in the analysis after propensity score matching. Compared with CCRT alone, CCRT with DC was associated with increased progression-free survival (median: 13.3 vs. 7.6 months, hazard ratio[HR]: 0.63, 95% confidence interval[CI]: 0.42-0.96) and overall survival (HR: 0.47, 95% CI: 0.27-0.82) without an increased risk of adverse events requiring systemic antibiotics or steroids. While there were differences in patient characteristics between the present real-world study and the pivotal randomized controlled trial, we demonstrated significant survival benefits and tolerable safety with DC after the completion of CCRT.

Recurrence patterns and progression-free survival after chemoradiotherapy with or without consolidation durvalumab for stage III non-small cell lung cancer

Chemoradiotherapy followed by consolidation durvalumab (CCRT+D) improves survival in patients with stage III non-small-cell lung cancer (NSCLC). We compared recurrence patterns and survival in the CCRT+D and CCRT cohorts. We conducted a multicenter, retrospective study in Japan. Patients who received CCRT for stage III NSCLC were included in this study. Of 178 eligible patients, 136 were in the CCRT+D and 42 were in the CCRT cohorts. Locoregional recurrence (LR), LR plus distant metastases (DM), and DM were observed in 20.6%, 8.8%, 27.9% of the CCRT+D, and 26.2%, 16.7% and 33.3% of the CCRT cohorts, respectively. In-field recurrence was the most common LR pattern in both cohorts. Squamous cell carcinoma and PD-L1 expression < 1%, and female sex and EGFR mutations were significantly associated with an increased risk of LR and DM. In patients with any risk factors for LR, the incidence of LR was similar in the CCRT+D and CCRT (39.5% vs 45.5%). The 24 month progression-free survival (PFS) and overall survival (OS) were 40.3% and 69.4% in the CCRT+D and 24.7% and 61.0% in the CCRT cohorts, respectively. Poor performance status and no consolidation durvalumab were significantly associated with shorter PFS. There was a significant difference in PFS between the CCRT+D and CCRT in the propensity score-matched cohort (HR = 0.51, P = 0.005). In conclusion, consolidation durvalumab decreased both LR and DM, and significantly improved PFS. However, in-field recurrence was still a major problem, as well as DM.

Current challenges of unresectable stage III NSCLC: are we ready to break the glass ceiling of the PACIFIC trial?

Consolidation anti-programmed death-ligand 1 has become a new standard of care in unresectable stage III non-small cell lung cancer (NSCLC) following chemo-radiotherapy (CTRT), based on the results of two phase III trials. Advances remain however needed, in particular to reduce the risk of distant relapse and for treatment personalization. Newer strategies are currently being tested, including consolidation with dual immune checkpoint inhibitors (ICIs), concurrent chemo-radioimmunotherapy and (chemo)-immunotherapy induction before CTRT. One randomized phase II reported better outcomes with a double ICI consolidation as compared with durvalumab alone. Three nonrandomized phase II trials also suggested that concurrent ICI-CTRT was feasible. Within this review, we summarize the current evidence, highlight ongoing trials and discuss challenges that will ideally lead to a cure for more patients with unresectable stage III NSCLC.

Limited Benefit from the Addition of Immunotherapy to Chemotherapy in TKI-Refractory EGFR-Mutant Lung Adenocarcinoma

Simple Summary

Although it is known that anti-PD1/L1 monotherapy does not render significant benefit in patients with EGFR-mutant lung adenocarcinoma, whether the addition of anti-PD1/L1 therapy to chemotherapy can enhance chemotherapy efficacy for TKI-refractory EGFR-mutant lung adenocarcinoma patients is not clear. To address this question, we retrospectively analyzed a cohort of 178 EGFR-mutant lung adenocarcinoma patients who had progressed on EGFR TKIs and received subsequent non-TKI systemic therapy to determine whether the addition of immunotherapy to chemotherapy truly improves clinical outcomes. We found that the addition of anti-PD1 immunotherapy did not add benefit to the platinum-based chemotherapy at the time of TKI progression for EGFR-mutant LUAD. Although underpowered, the anti-VEGF therapy demonstrated a trend towards adding benefit. As ongoing clinical trials with newer agents or combinations demonstrate preliminary efficacy in TKI-resistant EGFR-mutant LUAD patients, the ideal choice for post-TKI treatment is still being evaluated.

Abstract

Background: The benefit of chemotherapy combined with immunotherapy in EGFR-mutant lung adenocarcinoma (LUAD) patients whose tumor developed resistance to EGFR tyrosine kinase inhibitors (TKIs) is not thoroughly investigated. The goal of this retrospective cohort study is to assess the clinical efficiency of immunotherapy alone or in combination with chemotherapy in a real-world setting. Methods: This retrospective cohort study enrolled LUAD patients with EGFR sensitive mutations whose tumor had acquired resistance to EGFR TKIs and received systemic treatment with chemotherapy (chemo; n = 84), chemotherapy combined with immunotherapy (chemoIO; n = 30), chemotherapy plus bevacizumab with or without IO (withBev; n = 42), and IO monotherapy (IO-mono; n = 22). Clinical progression-free survival (PFS) and overall survival (OS) were evaluated. Associations of clinical characteristics with outcomes were assessed using univariable and multi-covariate Cox Proportional Hazards regression models. Results: A total of 178 patients (median age = 63.3; 57.9% females) with a median follow-up time of 42.0 (Interquartile range: 22.9–67.8) months were enrolled. There was no significant difference in PFS between chemoIO vs. chemo groups (5.3 vs. 4.8 months, p = 0.8). Compared to the chemo group, patients who received withBev therapy trended towards better PFS (6.1 months vs. 4.8; p = 0.3; HR 0.79; 95% CI: 0.52–1.20), while patients treated with IO-mono had inferior PFS (2.2 months; p = 0.001; HR 2.22; 95% CI: 1.37–3.59). Furthermore, PD-L1 level was not associated with PFS benefit in the chemoIO group. Patients with EGFR-mutant LUAD with high PD-L1 (≥50%) had shorter PFS (5.8 months) than non-EGFR/ALK LUAD patients who received chemoIO (12.8 months, p = 0.002; HR 0.22; 95% CI: 0.08–0.56) as first-line treatment. Chemotherapy-based therapy rendered similar benefit to patients with either EGFR exon19 deletion vs. L858R in the LUAD. Conclusions: This retrospective analysis revealed that immunotherapy provided limited additional benefit to chemotherapy in TKI-refractory EGFR-mutant LUAD. Chemotherapy alone or combined with bevacizumab remain good choices for patients with actionable EGFR mutations.