Breaking the biomarker code: PD-L1 expression and checkpoint inhibition in advanced NSCLC

Long-term survival outcomes and immune checkpoint inhibitor retreatment in patients with advanced cervical cancer treated with camrelizumab plus apatinib in the phase II CLAP study

BACKGROUND

Camrelizumab plus apatinib have demonstrated robust antitumor activity and safety in patients with advanced cervical cancer (CLAP study; NCT03816553). We herein present the updated long-term results of the CLAP study and explore potential biomarkers for survival. The outcomes of patients who underwent immune checkpoint inhibitor (ICI) retreatment were also reported.

METHODS

In this phase II trial, eligible patients received camrelizumab 200 mg intravenously every two weeks and apatinib 250 mg orally once daily in 4-week cycles for up to two years. Treatment was continued until disease progression, unacceptable toxicity, or withdrawal of consent.

RESULTS

Between January 21 and August 1, 2019, a total of 45 patients were enrolled. Data were analyzed as of July 31, 2023, representing > 48 months since treatment initiation for all patients. Nine (20.0%) patients completed the 2-year study. The median duration of response (DOR) was 16.6 months, and 45.0% of patients achieved a DOR of ≥ 24 months. The 12-month progression-free survival (PFS) rate was 40.7% (95% confidence interval [CI], 25.2-55.6), with an 18-month PFS rate of 37.8% (95% CI, 22.7-52.8). The median overall survival (OS) was 20.3 months (95% CI, 9.3-36.9), and the 24-month OS rate was 47.8% (95% CI, 31.7-62.3). Age > 50 years, programmed death-ligand 1 (PD-L1) combined positive score (CPS) ≥ 1 (versus [vs.] < 1), CPS ≥ 10 (vs. < 1), high tumor mutational burden, and PIK3CA mutations were associated with improved PFS (hazard ratio [HR] < 1) and longer OS (HR < 1). Eight patients who initially responded in the CLAP trial but later experienced disease progression were retreated with ICIs. Among them, 2 (25.0%) achieved a partial response, while 5 (62.5%) had stable disease. Notably, four patients who received retreatment with ICIs survived for more than 45 months. No new safety signals were identified in the present study.

CONCLUSION

Long-term survival follow-up data demonstrated that camrelizumab plus apatinib has robust, sustained, and durable efficacy in patients with advanced cervical cancer who progress after first-line platinum-based chemotherapy. No new safety signals were noted with long-term treatment.

Is neoadjuvant immunotherapy necessary in patients with programmed death ligand 1 expression-negative resectable non-small cell lung cancer? A systematic review and meta-analysis

OBJECTIVES

The aim of this study was to investigate the clinical benefit and necessity of neoadjuvant programmed cell death (or ligand) (PD-(L)1) blockades in resectable non-small cell lung cancer (NSCLC) patients with negative PD-L1 expression.

MATERIALS AND METHODS

Randomized control trials (RCTs) that compared event-free survival (EFS), overall survival (OS), major pathological response (MPR), and/or pathological complete response (pCR) between neoadjuvant chemo-immunotherapy (nCIT) and neoadjuvant chemotherapy (nCT) for patients with resectable NSCLC stratified by PD-L1 expression were eligible for inclusion in the study. Data regarding the pathological response and EFS were evaluated by the odds ratio (OR) and hazard ratio (HR) with 95% confidence interval (CI) using random and fixed models.

RESULTS

A total of six RCTs involving 3,194 patients with resectable NSCLC with or without neoadjuvant immunotherapy were included. Compared with nCT alone, nCIT significantly improved pCR (18.3 % vs. 3.0 %; OR, 5.64; 95 % CI, 3.22-9.89; P < 0.001), MPR (38.9 % vs. 15.5 %; OR, 3.57; 95 % CI, 2.10-6.05; P < 0.001), and EFS (HR, 0.75; 95 % CI, 0.62-0.90; P = 0.002) in PD-L1 <1 % NSCLC patients. In addition, PD-L1 ≥1 % was associated with higher rates of pCR (32.8 % vs. 18.3 %; OR, 2.28; 95 % CI, 1.40-3.73; P = 0.001) and MPR (53.9 % vs. 38.9 %; OR, 1.84; 95 % CI, 1.22-2.79; P = 004) and longer EFS (HR, 0.44 vs. 0.75) in the setting of nCIT compared with PD-L1 <1 %. nCIT improved only OS in NSCLC patients with PD-L1 ≥1 % but not in patients with PD-L1 <1 %.

CONCLUSIONS

The use of nCIT should be recommended for resectable NSCLC patients with negative PD-L1 expression, as nCIT significantly improved the pathological response and EFS in these patients. The benefit to PD-L1-negative patients treated with nCIT on OS remains to be validated.

Development and Evaluation of a Quantitative Systems Pharmacology Model for Mechanism Interpretation and Efficacy Prediction of Atezolizumab in Combination with Carboplatin and Nab-Paclitaxel in Patients with Non-Small-Cell Lung Cancer

Immunotherapy has shown clinical benefit in patients with non-small-cell lung cancer (NSCLC). Due to the limited response of monotherapy, combining immune checkpoint inhibitors (ICIs) and chemotherapy is considered a treatment option for advanced NSCLC. However, the mechanism of combined therapy and the potential patient population that could benefit from combined therapy remain undetermined. Here, we developed an NSCLC model based on the published quantitative systems pharmacology (QSP)-immuno-oncology platform by making necessary adjustments. After calibration and validation, the established QSP model could adequately characterise the biological mechanisms of action of the triple combination of atezolizumab, nab-paclitaxel, and carboplatin in patients with NSCLC, and identify predictive biomarkers for precision dosing. The established model could efficiently characterise the objective response rate and duration of response of the IMpower131 trial, reproducing the efficacy of alternative dosing. Furthermore, CD8+ and CD4+ T cell densities in tumours were found to be significantly related to the response status. This significant extension of the QSP model not only broadens its applicability but also more accurately reflects real-world clinical settings. Importantly, it positions the model as a critical foundation for model-informed drug development and the customisation of treatment plans, especially in the context of combining single-agent ICIs with platinum-doublet chemotherapy.

Synthesis and preliminary biological evaluation of a novel 99mTc-labeled small molecule for PD-L1 imaging

In recent years, PD-1/PD-L1 checkpoint blockade immunotherapy with remarkable efficacy has set off a heat wave. The expression level of PD-L1, which plays a predictive role in anti-PD-1/PD-L1 therapy, could be quantified by noninvasive imaging with radiotracers. Herein, we introduced the synthesis and preliminary biological evaluation of a novel 99mTc-labeled small molecule radiotracer [99mTc]G3C-CBM for PD-L1 imaging. [99mTc]G3C-CBM was achieved with high radiochemical purity (>96 %) and remained good stability in PBS and FBS. In competitive combination experiment, [99mTc]G3C-CBM was displaced by increasing concentrations of unlabeled G3C-CBM, resulting in an IC50 value of 41.25±2.23 nM for G3C-CBM. The uptake of [99mTc]G3C-CBM in A375-hPD-L1 cells (17.51±2.08 %) was approximately 6.47 folds of that in A375 cells (2.71±0.36 %) after co-incubation for 2 h. The biodistribution results showed that the radioactivity uptake in A375-hPD-L1 tumor reached the maximum (0.35±0.01 %ID/g) at 2 h post injection, and the optimum tumor/muscle ratio of 2.94±0.29 occurred at the same time. In addition, [99mTc]G3C-CBM was quickly cleared from the blood with a clearance half-life of just 119.25 min. These results indicate that [99mTc]G3C-CBM is a potential SPECT PD-L1 imaging agent and is worthy of further study.

GPX4 Plays a Crucial Role in Fuzheng Kang’ai Decoction-Induced Non-Small Cell Lung Cancer Cell Ferroptosis

Background: Fuzheng Kang’ai decoction (FZKA) has been widely used to treat Non-Small Cell Lung Cancer (NSCLC) patients in China for decades, showing definitively curative effects in clinic. Recently, we found that FZKA could induce NSCLC cell ferroptosis, another type of programmed cell death (PCD), which is totally different from cell apoptosis. Therefore, in the present study, we aim to discover the exact mechanism by which FZKA induces NSCLC cell ferroptosis, which is rarely studied in Traditional Chinese Medicine (TCM).

Methods: Cell proliferation assay were performed to detect the cell viability. Cell ferroptosis triggered by FZKA was observed by performing lipid peroxidation assay, Fe²⁺ Ions assay, and mitochondrial ultrastructure by transmission electron microscopy. Ferroptosis inhibitors including liproxstatin-1 and UAMC 3203 were used to block ferroptosis. The ratio of GSH/GSSG was done to measure the alteration of oxidative stress. Western blot and qRT-PCR were carried out to detect the expression of solute carrier family 7 member 11 (SLC7A11), solute carrier family 3 member 2 (SLC3A2) and glutathione peroxidase 4 (GPX4) at protein and mRNA levels, respectively. Lentivirus transfection was performed to overexpress GPX4 stably. Animal model was done to verify the effect of FZKA-induced ferroptosis in NSCLC in vivo and immunohistochemistry was done to detect the expression of SLC7A11, SLC3A2 and GPX4 at protein level.

Results: First of all, in vitro experiments confirmed the inhibition effect of FZKA on NSCLC cell growth. We then, for the first time, found that FZKA induced NSCLC cell ferroptosis by increasing lipid peroxidation and cellular Fe²⁺ Ions. Moreover, characteristic morphological changes of NSCLC cell ferroptosis was observed under transmission electron microscopy. Mechanistically, GPX4, as a key inhibitor of lipid peroxidation, was greatly suppressed by FZKA treatment both at protein and mRNA levels. Furthermore, system xc⁻ (SLC7A11 and SLC3A2) were found to be suppressed and a decreased GSH/GSSG ratio was observed at the same time when treated with FZKA. Notably, overexpressing GPX4 reversed the effect of FZKA-induced NSCLC cell ferroptosis significantly. Finally, the above effect was validated using animal model in vivo.

Conclusion: Our findings conclude that GPX4 plays a crucial role in FZKA-induced NSCLC cell ferroptosis, providing a novel molecular mechanism by which FZKA treats NSCLC.

Pretreatment Fibrinogen-Albumin Ratio (FAR) Associated with Treatment Response and Survival in Advanced Non-Small Cell Lung Cancer Patients Treated with First-Line Anti-PD-1 Therapy Plus Platinum-Based Combination Chemotherapy

Purpose

PD-1 inhibitors have been routinely used to treat advanced non-small cell lung cancer (NSCLC) and have significantly improved clinical outcomes. In this study, we aimed to explore the influence of pretreatment fibrinogen-albumin ratio (FAR) on treatment response and survival in advanced NSCLC patients treated with first-line anti-PD-1 therapy plus platinum-based combination chemotherapy.

Patients and Methods

A total of 91 patients with advanced NSCLC were included in the study. All patients received at least two cycles of systemic first-line anti-PD-1 therapy plus platinum-based combination chemotherapy. Receiver operating characteristics analysis was performed to determine the optimal cutoff values of FAR. Univariate and multivariate analyses were used to identify independent prognostic factors, and the Kaplan–Meier method was used to estimate survival curves.

Results

Multivariate logistic regression analysis showed that N stage (N2-3) and high FAR (≥0.175, optimal cutoff value) were independent predictors for objective response rate (P = 0.0002, P = 0.0005, respectively). Multivariate Cox regression analysis of progression-free survival and overall survival showed that high FAR (≥0.145) was independent prognostic factors (P = 0.0061, P = 0.0024, respectively). Progression-free survival and overall survival were significantly shorter in the high FAR (≥0.145) group than those in the low FAR (<0.145) group (P = 0.0024, P = 0.0024, respectively).

Conclusion

Pretreatment FAR was an independent predictor for treatment response and independent prognostic factors in advanced NSCLC patients treated with first-line anti-PD-1 therapy plus platinum-based combination chemotherapy.

Machine Learning for Prediction of Immunotherapy Efficacy in Non-Small Cell Lung Cancer from Simple Clinical and Biological Data

BACKGROUND

Immune checkpoint inhibitors (ICIs) are now a therapeutic standard in advanced non-small cell lung cancer (NSCLC), but strong predictive markers for ICIs efficacy are still lacking. We evaluated machine learning models built on simple clinical and biological data to individually predict response to ICIs.

METHODS

Patients with metastatic NSCLC who received ICI in second line or later were included. We collected clinical and hematological data and studied the association of this data with disease control rate (DCR), progression free survival (PFS) and overall survival (OS). Multiple machine learning (ML) algorithms were assessed for their ability to predict response.

RESULTS

Overall, 298 patients were enrolled. The overall response rate and DCR were 15.3% and 53%, respectively. Median PFS and OS were 3.3 and 11.4 months, respectively. In multivariable analysis, DCR was significantly associated with performance status (PS) and hemoglobin level (OR 0.58, p < 0.0001; OR 1.8, p < 0.001). These variables were also associated with PFS and OS and ranked top in random forest-based feature importance. Neutrophil-to-lymphocyte ratio was also associated with DCR, PFS and OS. The best ML algorithm was a random forest. It could predict DCR with satisfactory efficacy based on these three variables. Ten-fold cross-validated performances were: accuracy 0.68 ± 0.04, sensitivity 0.58 ± 0.08; specificity 0.78 ± 0.06; positive predictive value 0.70 ± 0.08; negative predictive value 0.68 ± 0.06; AUC 0.74 ± 0.03.

CONCLUSION

Combination of simple clinical and biological data could accurately predict disease control rate at the individual level.

The benefits and risks of pembrolizumab in combination with chemotherapy as first-line therapy in small-cell lung cancer: a single-arm meta-analysis of noncomparative clinical studies and randomized control trials

BACKGROUND

Although pembrolizumab has shown clinical benefit in patients with small-cell lung cancer (SCLC), its actual efficacy in combination with a conventional chemotherapy drug has not been determined. We performed this study to discern the efficacy and risk of pembrolizumab in combination with chemotherapy as first-line therapy in SCLC patients.

METHODS

We systematically searched the PubMed, ScienceDirect, Cochrane Library, Scopus, Ovid MEDLINE, Embase, Web of Science, and Google Scholar databases for relevant studies. The main outcomes were overall survival (OS) and progression-free survival (PFS).

RESULTS

We identified 2980 articles and included 6 studies (5 were noncomparative open-label studies and 1 was a randomized controlled trial [RCT]) involving 396 patients in our meta-analysis. The pooled median OS (mOS) was 9.6 months (95% CI, 8.0-11.2), and the pooled median PFS (mPFS) was 4.2 months (95% CI, 2.2-6.1). The 1-year overall survival rate (OSR-1y) and 6-month progression-free survival rate (PFSR-6m) were 45.1% (95% CI, 33-57.2%) and 41.6% (95% CI, 24.3-59%), respectively. The objective response rate (ORR) was 38.8% (95% CI, 11.9-65.67%), disease control rate (DCR) was 69.30% (95% CI, 51.6-87.0%), complete response (CR) was 2.20% (95% CI, 0.8-3.7%), partial response (PR) was 34.70% (95% CI, 7.8-61.5%), and stable disease (SD) was 20.90% (95% CI, 9.1-32.6%). The grade 3-4 adverse effect (AE) rate was 20.88% (95% CI, 1.22-54.85%). The most common AEs were neutropenia (90.16%), anemia (53.21%), dysphagia (41.96%), platelet count decrease (34.87%), and esophagitis (32.89%); severe AEs included neutropenia, respiratory failure, pneumonitis, acute coronary syndrome, and colitis/intestinal ischemia.

CONCLUSIONS

The combination of pembrolizumab with conventional chemotherapy is an effective therapeutic schedule with acceptable and manageable efficacy and toxicity in patients with SCLC. More high-quality and well-designed RCTs with large sample sizes are warranted to further validate our findings.

Combination Treatment With Inhibitors of ERK and Autophagy Enhances Antitumor Activity of Betulinic Acid in Non-small-Cell Lung Cancer In Vivo and In Vitro

Aberrant activation of the Ras-ERK signaling pathway drives many important cancer phenotypes, and several inhibitors targeting such pathways are under investigation and/or approved by the FDA as single- or multi-agent therapy for patients with melanoma and non-small-cell lung cancer (NSCLC). Here, we show that betulinic acid (BA), a natural pentacyclic triterpenoid, inhibits cell proliferation, and induces apoptosis and protective autophagy in NSCLC cells. Thus, the cancer cell killing activity of BA is enhanced by autophagy inhibition. Mitogen-activated protein kinases, and especially ERK that facilitates cancer cell survival, are also activated by BA treatment. As such, in the presence of ERK inhibitors (ERKi), lung cancer cells are much more sensitive to BA. However, the dual treatment of BA and ERKi results in increased protective autophagy and AKT phosphorylation. Accordingly, inhibition of AKT has a highly synergistic anticancer effect with co-treatment of BA and ERKi. Notably, autophagy inhibition by hydroxychloroquine (HCQ) increases the response of lung cancer cells to BA in combination with ERKi. In vivo, the three-drug combination (BA, ERKi, and HCQ), resulted in superior therapeutic efficacy than single or dual treatments in the xenograft mouse model. Thus, our study provides a combined therapy strategy that is a highly effective treatment for patients with NSCLC.

The Application of Combined Immune Checkpoint Inhibitor Modalities in Previously Treated Non-Small Cell Lung Cancer Patients and the Associations Thereof With the Lung Immune Prognostic Index

Background

Immune checkpoint inhibitor (ICI) monotherapy remains the standard of care for patients with previously treated non-small cell lung cancer. However, few reports have compared the clinical benefits of second-line ICIs alone with those of ICIs combined with other therapies, including anti-angiogenesis therapy or chemotherapy.

Methods

Patients with previously treated advanced non-small cell lung cancer who received ICIs were retrospectively reviewed. The progression-free survival (PFS), overall survival, objective response rate, disease control rate, and safety were assessed. Complete blood cell counts and serum lactate dehydrogenase (LDH) levels were measured before and after ICI treatment.

Results

Of 120 patients, 75 were treated with ICI monotherapy, 26 with ICIs plus anti-angiogenic therapy (ICI+A), and 19 with ICIs plus chemotherapy (ICI+C). The objective response rate was significantly higher in the ICI+C group (57.9%) than ICI monotherapy (26.3%) and ICI+A (31.8%) groups. The depth of response was significantly greater in the ICI+C (-35.1%) than ICI+A (-2.04%) and ICI monotherapy (3.963%) groups. ICI+C afforded a better PFS compared with the ICI monotherapy and ICI+A groups (8.5 vs. 4.6 and 4.1 months, respectively). Notably, the pre- and post-treatment peripheral neutrophil/lymphocyte ratios and serum LDH levels were negatively correlated with the PFS of the entire cohort. More importantly, the pretreatment lung immune prognostic index (neutrophil/lymphocyte ratio ≥ 4 and LDH level ≥ upper limit of normal) satisfactorily predicted the responses to ICI-based strategies. Adverse events (AEs) occurred in 65.3%, 92.3%, and 94.7% of patients in the ICI monotherapy, ICI+A, and ICI+C groups, respectively. Grade 3-5 AEs were more common in the combination therapy groups (ICI+A, 19.2%; ICI+C, 21%; ICI monotherapy, 4%).

Conclusion

In second-line settings and beyond, ICIs combined with chemotherapy prolonged survival, with tolerable AEs. Addition of anti-angiogenic agents to ICIs did not afford any additional benefits. Further prospective studies are warranted.

Non-invasive immunoPET imaging of PD-L1 using anti-PD-L1-B11 in breast cancer and melanoma tumor model

INTRODUCTION

Immunotherapy targeting PD-1/PD-L1 immune checkpoint inhibition (ICI) is efficacious in various solid and hematologic malignancies. However, the response rate to PD-1/PD-L1 therapy is only 15-35%. To obtain optimal clinical response to ICI therapies, a reliable assessment of tumor PD-L1 expression is needed to select appropriate patients, and a non-invasive imaging-based assessment of PD-L1 expression is critically needed. Although radiolabeled PET probes based on PD-L1 targeted therapeutic antibodies (e.g. atezolizumab) have shown encouraging results, there is concern that residual therapeutic antibody may compete for binding with the radiotracer thereby compromising imaging studies that follow treatment.

METHODS AND RESULTS

In this study, we used novel anti-PD-L1-B11 clone antibody known to bind to a different epitope of PD-L1 than the therapeutic antibodies to avoid potential saturation effects. The anti-PD-L1-B11 clone was radiolabeled with zirconium-89 and evaluated to detect PD-L1 expression in various in vitro and in vivo cancer model systems in comparison with [⁸⁹Zr]Zr-DFO-NCS-atezolizumab. In vitro binding parameters of anti-PD-L1-B11 were like those of atezolizumab. [⁸⁹Zr]Zr-DFO-NCS-anti-PD-L1-B11 clone showed favorable properties to [⁸⁹Zr]Zr-DFO-NCS-atezolizumab in an in vivo breast cancer tumor model system with higher uptake in PD-L1 expressing tumors.

CONCLUSION

Our data demonstrates that [⁸⁹Zr]Zr-DFO-NCS-anti-PD-L1-B11 exhibits excellent imaging properties for the assessment PD-L1 expression. The independent binding site of anti-PD-L1-B11 relative to therapeutic anti-PD-L1 antibodies may be advantageous for anti-PD-L1 therapy monitoring.

Biomarkers or factors for predicting the efficacy and adverse effects of immune checkpoint inhibitors in lung cancer: achievements and prospective

Immune checkpoint inhibitors (ICIs) are widely used in lung cancer therapy due to their effectiveness and minimal side effects. However, only a few lung cancer patients benefit from ICI therapy, driving the need to develop alternative biomarkers. Programmed death-ligand 1 (PD-L1) molecules expressed in tumor cells and immune cells play a key role in the immune checkpoint pathway. Therefore, PD-L1 expression is a prognostic biomarker in evaluating the effectiveness of programmed death-1 (PD-1)/PD-L1 inhibitors. Nevertheless, adverse predictive outcomes suggest that other factors are implicated in the response. In this review, we present a detailed introduction of existing biomarkers concerning tumor abnormality and host immunity. PD-L1 expression, tumor mutation burden, neoantigens, specific gene mutations, circulating tumor DNA, human leukocyte antigen class I, tumor microenvironment, peripheral inflammatory cells, and microbiome are discussed in detail. To sum up, this review provides information on the current application and future prospects of ICI biomarkers.

Clinical Correlations of Programmed Cell Death Ligand 1 Status in Liquid and Standard Biopsies in Breast Cancer

BACKGROUND

Data regarding the prognostic value of programmed cell death ligand 1 (PD-L1) expression on circulating tumor cells (CTCs) are lacking. However, CTCs could represent an alternative approach to serial biopsies, allowing real-time monitoring of cancer phenotype.

METHODS

We evaluated, in a dedicated prospective clinical trial, the clinicopathological correlations and prognostic value of PD-L1(+)-CTCs in 72 patients with metastatic breast cancer (MBC).

RESULTS

Eighteen of 56 patients with available archival tissue presented at least one positive (≥1%) PD-L1 tumor sample. Baseline CTCs and PD-L1(+)-CTCs were detected in 57 (79.2%) and 26 (36.1%) patients. No significant correlation was found between PD-L1 tumors and CTC expression. In univariate analysis, triple negative (TN) phenotype, number of metastatic treatments, >2 metastatic sites, ≥5 CTCs and PD-L1(+)-CTCs were significantly associated with progression-free survival, while tissue PD-L1 expression was not. In multivariate analysis, TN phenotype, number of metastatic treatments and of metastatic sites were the only 3 variables independently associated with progression-free survival. Progesterone receptor negativity, TN phenotype, >2 metastatic sites and ≥5 CTCs were significantly associated with overall survival in univariate analysis. In multivariable analysis, TN phenotype and >2 metastatic sites were the only 2 independent variables.

CONCLUSIONS

Unlike PD-L1(+)-tumor, PD-L1(+)-CTCs correlate to survival in MBC. Reappraisal of the role of PD-L1 expression by tumor tissue and by CTCs under anti-PD-1/PD-L1 treatment is necessary to evaluate its predictive value and potential role as a stratifying factor in strategies and trials for MBC patients with MBC.

CLINICAL TRIAL REGISTRATION

NCT02866149.

Efficacy and safety of sintilimab in combination with chemotherapy in previously untreated advanced or metastatic nonsquamous or squamous NSCLC: two cohorts of an open-label, phase 1b study

Combining chemotherapy with immunotherapy improves the therapeutic outcome for first-line (1L) patients with advance nonsmall-cell lung cancer (NSCLC). Two cohorts of a phase 1b study (NCT02937116) aimed to evaluate the safety and efficacy of sintilimab, a PD-1 inhibitor, plus chemotherapy in 1L patients with nonsquamous and squamous NSCLC (nsqNSCLC/sqNSCLC); and to identify potential biomarkers for treatment response. Treatment-naïve patients with nsqNSCLC were enrolled and intravenously given sintilimab (200 mg), pemetrexed (500 mg/m2), and cisplatin (75 mg/m2), every 3 weeks (Q3W) for 4 cycles in cohort D. Treatment-naïve patients with sqNSCLC were enrolled and intravenously given sintilimab (200 mg), gemcitabine (1250 mg/m2), and cisplatin (75 mg/m2), Q3W, for 6 cycles in cohort E. The primary objective was to evaluate the safety and efficacy of the treatment. The additional objective was to explore biomarkers for the treatment efficacy. Twenty-one patients with nsqNSCLC, and 20 patients with sqNSCLC were enrolled in cohort D and cohort E, respectively. By the data cutoff (April 17, 2019), 8 (38.1%) patients in cohort D and 17 (85.0%) patients in cohort E experienced grade 3-4 adverse events. The median follow-up duration was 16.4 months (14.8-23.0) in cohort D and 15.9 months (11.7-17.7) in cohort E. The objective response rate was 68.4% (95% CI 43.4%, 87.4%) in cohort D and 64.7% (95% CI 38.3%, 85.8%) in cohort E. Neither PD-L1 expression nor tumor mutation burden value was significantly associated with an improved treatment response. Sintilimab plus chemotherapy exhibited manageable toxicity and an encouraging antitumor activity in patients with nsqNSCLC and sqNSCLC.

Quantifying PD-L1 Expression to Monitor Immune Checkpoint Therapy: Opportunities and Challenges

Simple Summary

Malignant cells hijack the regulatory roles of immune checkpoint proteins for immune evasion and survival. Therapeutics blocking those proteins can restore the balance of the immune system and lead to durable responses in cancer patients. Although a subset of patients derive benefit, there are few non-invasive technologies to guide and monitor those therapies to improve success rates. This is a review of the advancements in non-invasive methods for quantification of immune checkpoint protein programmed death ligand 1 expression, a biomarker detected by immunohistochemistry and widely used for guiding immune checkpoint therapy.

Abstract

Therapeutics targeting programmed death ligand 1 (PD-L1) protein and its receptor PD-1 are now dominant players in restoring anti-tumor immune responses. PD-L1 detection by immunohistochemistry (IHC) is emerging as a reproducible biomarker for guiding patient stratification for those therapies in some cancers. However, PD-L1 expression in the tumor microenvironment is highly complex. It is upregulated by aberrant genetic alterations, and is highly regulated at the transcriptional, posttranscriptional, and protein levels. Thus, PD-L1 IHC is inadequate to fully understand the relevance of PD-L1 levels in the whole body and their dynamics to improve therapeutic outcomes. Imaging technologies could potentially assist in meeting that need. Early clinical investigations show promising results in quantifying PD-L1 expression in the whole body by positron emission tomography (PET). Within this context, this review summarizes advancements in regulation of PD-L1 expression and imaging agents, and in PD-L1 PET for drug development, and discusses opportunities and challenges presented by these innovations for guiding immune checkpoint therapy (ICT).

Identification of Clonal Neoantigens Derived From Driver Mutations in an EGFR-Mutated Lung Cancer Patient Benefitting From Anti-PD-1

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been recommended as the first-line therapy for non-small cell lung cancer (NSCLC) patients harboring EGFR mutations. However, acquired resistance to EGFR-TKIs is inevitable. Although immune checkpoint blockades (ICBs) targeting the programmed cell death 1 (PD-1)/PD-ligand (L)1 axis have achieved clinical success for many cancer types, the clinical efficacy of anti-PD-1/PD-L1 blockades in EGFR mutated NSCLC patients has been demonstrated to be lower than those without EGFR mutations. Here, we reported an advanced NSCLC patient with EGFR driver mutations benefitting from anti-PD-1 blockade therapy after acquiring resistance to EGFR-TKI. We characterized the mutational landscape of the patient with next-generation sequencing (NGS) and successfully identified specific T-cell responses to clonal neoantigens encoded by EGFR exon 19 deletion, TP53 A116T and DENND6B R398Q mutations. Our findings support the potential application of immune checkpoint blockades in NSCLC patients with acquired resistance to EGFR-TKIs in the context of specific clonal neoantigens with high immunogenicity. Personalized immunomodulatory therapy targeting these neoantigens should be explored for better clinical outcomes in EGFR mutated NSCLC patients.

Efficacy of PD-1/PD-L1 blockade monotherapy in clinical trials

Background:

Inhibitors targeting programmed cell death 1 (PD-1) and programmed death-ligand 1 (PD-L1) have unprecedented effects in cancer treatment. However, the objective response rates (ORRs), progression-free survival (PFS), and overall survival (OS) of PD-1/PD-L1 blockade monotherapy have not been systematically evaluated.

Methods:

We searched Embase, PubMed, and Cochrane database from inception to July 2019 for prospective clinical trials on single-agent PD-1/PD-L1 antibodies (avelumab, atezolizumab, durvalumab, cemiplimab, pembrolizumab, and nivolumab) with information regarding ORR, PFS, and OS.

Results:

Totally, 28,304 patients from 160 perspective trials were included. Overall, 4747 responses occurred in 22,165 patients treated with PD-1/PD-L1 monotherapy [ORR, 20.21%; 95% confidence interval (CI), 18.34–22.15%]. Compared with conventional therapy, PD-1/PD-L1 blockade immunotherapy was associated with more tumor responses (odds ratio, 1.98; 95% CI, 1.52–2.57) and better OS [hazard ratio (HR), 0.75; 95% CI, 0.67–0.83]. The ORRs varied significantly across cancer types and PD-L1 expression status. Line of treatment, clinical phase and drug target also impacted the response rates in some tumors. A total of 2313 of 9494 PD-L1 positive patients (ORR, 24.39%; 95% CI, 22.29–26.54%) and 456 of 4215 PD-L1 negative patients (ORR, 10.34%; 95% CI, 8.67–12.14%) achieved responses. For PD-L1 negative patients, the ORR (odds ratio, 0.92; 95% CI, 0.70–1.20) and PFS (HR, 1.15; 95% CI, 0.87–1.51) associated with immunotherapy and conventional treatment were similar. However, PD-1/PD-L1 blockade monotherapy decreased the risk of death in both PD-L1 positive (HR, 0.66; 95% CI, 0.60–0.72) and PD-L1 negative (HR, 0.86; 95% CI, 0.74–0.99) patients compared with conventional therapy.

Conclusion:

The efficacies associated with PD-1/PD-L1 monotherapy vary significantly across cancer types and PD-L1 expression. This comprehensive summary of clinical benefit from immunotherapy in cancer patients provides an important guide for clinicians.

The Efficacy and Safety of PD-1/PD-L1 Inhibitors in Combination with Conventional Therapies for Advanced Solid Tumors: A Meta-Analysis

Objectives

To evaluate the efficacy of immuno-oncology combinational therapy (IOCT) versus monotherapy with programmed cell death 1 (PD-1) or PD-ligand 1 (PD-L1) inhibitors or conventional therapies, i.e., non-IOCT, in patients with advanced solid tumors.

Methods

We systematically searched the PubMed, Embase, and Cochrane Library databases from January 2015 to October 2018 for eligible studies. We included randomized trials of IOCT with available hazard ratios (HR) for death. The random effects model was used to calculate pooled HR for death; heterogeneity was assessed using I² statistics. The main outcome measure was overall survival (OS).

Results

After screening 483 relevant articles, we identified twelve trials comprising 5388 patients for quantitative analysis. IOCT-treated patients had significantly higher tumor response rate (relative risk (RR): 2.51, 95% confidence interval (CI): 1.82-3.47), prolonged progression-free survival (HR 0.62, 95% CI: 0.53-0.74), and OS (HR 0.69, 95% CI: 0.61-0.78), compared with non-IOCT–treated patients. Sensitivity analyses also demonstrated the OS advantage of IOCT across different combination modalities, intervention agents, malignancy types, and PD-L1 expression (all P < 0.05). Notably, there were higher odds of high-grade (grade ≥ 3) adverse events with IOCT (RR: 1.81, 95% CI: 1.13-2.90), but the risk of treatment-related death (RR: 1.16, 95% CI: 0.84–1.60) was not increased compared with non-IOCT.

Conclusions

IOCT is a preferable treatment option over PD-1/PD-L1 inhibitor monotherapy and conventional therapy for patients with advanced solid tumors. However, we should note the increased incidence rate of high-grade AEs in IOCT.

PD-L1 testing on the EBUS-FNA cytology specimens of non-small cell lung cancer

OBJECTIVES

The FDA approved PD-L1 tests for anti-PD-L1 immunotherapy are for surgical or histology specimens. It is not clear if cytology specimens could be used for PD-L1 testing to guide immunotherapy. In this study, we assess the suitability of EBUS-FNA cytology specimens for the testing of PD-L1.

MATERIALS AND METHODS

Consecutive patients with Non-small cell lung cancer (NSCLC) underwent EBUS procedure between January 1, 2017 and March 31, 2018 for PD-L1 testing were included. The cell blocks of EBUS-FNA cytology specimens were used for PD-L1 testing using Dako 22C3 phamDx antibody according to the Dako protocol. PD-L1 protein expression in tumor cells is determined by using Tumor Proportion Score (TPS).

RESULTS AND CONCLUSION

Of the 265 EBUS-FNA specimens from 262 patients sent for testing, 230 (86.8%) were adequate for PD-L1 testing. Of the 34 NSCLC patients with both histology and EBUS-FNA cytology specimens tested for PD-L1, the results from different specimen types had a concordance of 91.3%. The PD-L1 results from 16 paired specimens from the same anatomic site had 100% agreement. The rates of PD-L1 TPS ≥ 50% were significantly higher in the metastatic tumors in the lymph nodes than in the lung primary lesions. Therefore, EBUS-FNA cytology specimen is suitable for PD-L1 testing in patients with advanced NSCLC. The metastatic tumors in mediastinal lymph nodes appear to have higher PD-L1 expression than primary lesions.

Nivolumab alone or in combination with cisplatin plus gemcitabine in Japanese patients with unresectable or recurrent biliary tract cancer: a non-randomised, multicentre, open-label, phase 1 study

BACKGROUND

This study aimed to assess the safety and tolerability of the immune checkpoint inhibitor nivolumab, as monotherapy or combined with chemotherapy, in Japanese patients with biliary tract cancer.

METHODS

This multicentre, open-label, phase 1 trial was done at four cancer centres in Japan. Eligible patients were aged 20-79 years, had biliary tract adenocarcinoma (intrahepatic bile duct cancer, extrahepatic bile duct cancer, gallbladder cancer, or ampullary cancer), Eastern Cooperative Oncology Group performance status 0 or 1, adequate hepatic, renal, and haematological function, and tumour tissue samples for PD-L1 expression analysis. Patients with unresectable or recurrent biliary tract cancer that was refractory or intolerant to gemcitabine-based treatment regimens received nivolumab monotherapy (240 mg every 2 weeks [monotherapy cohort]). Chemotherapy-naive patients with unresectable or recurrent biliary tract cancer received nivolumab (240 mg every 2 weeks) and cisplatin (25 mg/m²) plus gemcitabine (1000 mg/m²) chemotherapy (combined therapy cohort). The primary objective was to assess tolerability and safety. The primary objective was assessed in the safety population of all patients who had received at least one dose of nivolumab. This study is registered with www.clinicaltrials.jp, number JapicCTI-153098, and follow-up is ongoing.

FINDINGS

30 patients were enrolled into each cohort between Jan 13, 2016, and April 19, 2017. Data cutoff was Aug 31, 2017. In the monotherapy cohort, the most frequently reported treatment-related adverse events were decreased appetite (five [17%]), malaise (four [13%]), and pruritus (four [13%]). Grade 3-4 treatment-related adverse events were reported by three (10%) patients (rash, maculopapular rash, and amylase increase) and treatment-related serious adverse events were reported by one (3%) patient (pleurisy). In the combined therapy cohort, the most frequently reported treatment-related adverse events were neutrophil count decrease (any grade 25 [83%]; grade 3-4 in 23 [77%] patients) and platelet count decrease (any grade 25 [83%] of 30; grade 3-4 in 15 [50%] patients). Six (20%) patients reported 11 treatment-related serious adverse events (platelet count decrease [three patients], febrile neutropenia [two patients], neutrophil count decrease, anaemia, anaphylactic reaction, decreased appetite, pyrexia, and myocarditis [one patient each]). In the monotherapy cohort, median overall survival was 5·2 months (90% CI 4·5-8·7), median progression-free survival was 1·4 months (90% CI 1·4-1·4), and one of 30 patients had an objective response. In the combined therapy cohort, median overall survival was 15·4 months (90% CI 11·8-not estimable), median progression-free survival was 4·2 months (90% CI 2·8-5·6), and 11 of 30 patients had an objective response.

INTERPRETATION

Nivolumab had a manageable safety profile and signs of clinical activity in patients with unresectable or recurrent biliary tract cancer. This initial assessment of nivolumab for the treatment of advanced biliary tract cancer provides supportive evidence for future larger randomised studies of nivolumab in this difficult to treat cancer.

FUNDING

Ono Pharmaceutical Co Ltd and Bristol-Myers Squibb Inc.

Peripheral Blood Markers Identify Risk of Immune-Related Toxicity in Advanced Non-Small Cell Lung Cancer Treated with Immune-Checkpoint Inhibitors

BACKGROUND

Immune-checkpoint inhibitors (ICIs) are now standard of care for advanced non-small cell lung cancer (NSCLC). Unfortunately, many patients experience immune-related adverse events (irAEs), which are usually mild and reversible, but they require timely management and may be life threatening. No predictive markers of irAEs are available.

MATERIALS AND METHODS

The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were evaluated in patients with NSCLC consecutively treated with ICIs. Prespecified cutoff values of NLR and PLR were used and related to outcome and onset of irAEs. A control group of patients with advanced NSCLC not receiving ICIs was included.

RESULTS

The study included 184 patients: 26 (14.1%) received pembrolizumab upfront, and 142 (77%) received ICIs (pembrolizumab, nivolumab or atezolizumab) after one or more lines of chemotherapy. The median number of ICIs cycles was six (range, 1-61). The median progression-free survival and overall survival were 4.8 (95% CI, 3.4-6.3) and 20.6 (95% CI, 14.7-26.5) months, respectively. Sixty patients (32.6%) developed irAEs, mainly grade 1-2 (65.0%), causing ICI interruption in 46 cases (25.0%). Low NLR and low PLR at baseline were significantly associated with the development of irAEs (odds ratio [OR], 2.2; p = .018 and OR, 2.8; p = .003, respectively). Multivariate analyses confirmed PLR as independent predictive marker of irAEs (OR, 2.3; p = .020).

CONCLUSION

NLR and PLR may predict the appearance of irAEs in non-oncogene-addicted aNSCLC, although this conclusion warrants prospective validation.

IMPLICATIONS FOR PRACTICE

This study was designed to investigate the role of blood biomarkers in predicting the occurrence of immune-related adverse events (irAEs) in patients with advanced non-small cell lung cancer receiving immunotherapy. The results of the study suggest a potential predictive role of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio as markers for irAE development in this category of patients. These data provide rationale for an easy and feasible application to be validated in clinical practice.

Can CpG methylation serve as surrogate markers for immune infiltration in cancer?

Recent reports describe how genome-wide transcriptional analysis of cancer tissues can be exploited to identify molecular signatures of immune infiltration in cancer. We hypothesize that immune infiltration in cancer may also be defined by changes in certain epigenetic signatures. In this context, a primary objective is to identify site-specific CpG markers whose levels of methylation may be highly indicative of known transcriptional markers of immune infiltration such as GZMA, PRF1, T cell receptor genes, PDCD1, and CTLA4. This has been accomplished by integrating genome-wide transcriptional expression and methylation data for different types of cancer (melanoma, kidney cancers, lung cancers, gliomas, head and neck cancer). Our findings establish that cancers of related histology also have a high degree of similarity in immune-infiltration CpG markers. For example, the epigenetic immune infiltration signatures in lung adenocarcinoma (LUAD), mesothelioma (MESO), lung squamous cell carcinoma (LUSC), and head and neck squamous cell carcinoma (HNSC) are distinctly similar. So are glioblastoma multiforme (GBM) and brain lower grade glioma (LGG); and kidney renal papillary cell carcinoma (KIRP) and kidney renal clear cell carcinoma (KIRC). Kidney chromophobe (KICH), on the other hand has markers that are unique to this cohort. The strong relationships between immune infiltration and CpG methylation (for certain sites) in cancer tissues were not observed upon integrated analysis of publicly available cancer cell line datasets. Results from comparative pathways analyses offer further justification to methylation at certain CpG sites as being indicators of cancer immune infiltration, and possibly of predicting patient response to immunotherapeutic drugs. Achieving this target objective would significantly enhance therapeutic outcomes employing immunotherapy through focused patient-centric personalized medicine.

Retrospective analysis of antitumor effects and biomarkers for nivolumab in NSCLC patients with EGFR mutations

Although the blockade of programmed cell death 1 (PD-1)/PD-ligand (L) 1 has demonstrated promising and durable clinical responses for non-small-cell lung cancers (NSCLCs), NSCLC patients with epidermal growth factor receptor (EGFR) mutations responded poorly to PD-1/PD-L1 inhibitors. Previous studies have identified several predictive biomarkers, including the expression of PD-L1 on tumor cells, for PD-1/PD-L1 blockade therapies in NSCLC patients; however, the usefulness of these biomarkers in NSCLCs with EGFR mutations has not been elucidated. The present study was conducted to evaluate the predictive biomarkers for PD-1/PD-L1 inhibitors in EGFR-mutated NSCLCs. We retrospectively analyzed 9 patients treated with nivolumab for EGFR-mutated NSCLCs. All but one patient received EGFR-tyrosine kinase inhibitors before nivolumab treatment. The overall response rate and median progression-free survival were 11% and 33 days (95% confidence interval (CI); 7 to 51), respectively. Univariate analysis revealed that patients with a good performance status (P = 0.11; hazard ratio (HR) 0.183, 95% CI 0.0217 to 1.549), a high density of CD4⁺ T cells (P = 0.136; HR 0.313, 95% CI 0.045 to 1.417) and a high density of Foxp3⁺ cells (P = 0.09; HR 0.264, 95% CI 0.0372 to 1.222) in the tumor microenvironment tended to have longer progression-free survival with nivolumab. Multivariate analysis revealed that a high density of CD4⁺ T cells (P = 0.005; HR<0.001, 95% CI <0.001 to 0.28) and a high density of Foxp3⁺ cells (P = 0.003; HR<0.001, 95% CI NA) in tumor tissues were strongly correlated with better progression-free survival. In contrast to previous studies in wild type EGFR NSCLCs, PD-L1 expression was not associated with the clinical benefit of anti-PD-1 treatment in EGFR-mutated NSCLCs. The current study indicated that immune status in the tumor microenvironment may be important for the effectiveness of nivolumab in NSCLC patients with EGFR mutations.

Early fatal hemoptysis after first-dose, first-line pembrolizumab in a central lung cancer: did tumor shrinkage matter?

A patient diagnosed with centrally located advanced lung adenocarcinoma with signs of large vessels infiltration, strongly expressing PD-L1, was candidate to first-line pembrolizumab. He had not complained of any bleeding manifestation before immunotherapy. 5 days after the first dose of pembrolizumab, the patient experienced massive, fatal hemoptysis. Given the central localization of the tumor and the strong PD-L1 expression, a contribution of rapid disease shrinkage is envisaged in determining the fatal hemorrhagic event. An attentive clinical attitude should be dedicated in centrally located and vessel-infiltrating tumors strongly expressing PD-L1 and candidate to anti-PD-1/PD-L1 agents.

Efficacy of PD-1 or PD-L1 inhibitors and PD-L1 expression status in cancer: meta-analysis

OBJECTIVE

To evaluate the relative efficacy of programmed cell death 1 (PD-1) or programmed cell death ligand 1 (PD-L1) inhibitors versus conventional drugs in patients with cancer that were PD-L1 positive and PD-L1 negative.

DESIGN

Meta-analysis of randomised controlled trials.

DATA SOURCES

PubMed, Embase, Cochrane database, and conference abstracts presented at the American Society of Clinical Oncology and European Society of Medical Oncology up to March 2018.

REVIEW METHODS

Studies of PD-1 or PD-L1 inhibitors (avelumab, atezolizumab, durvalumab, nivolumab, and pembrolizumab) that had available hazard ratios for death based on PD-L1 positivity or negativity were included. The threshold for PD-L1 positivity or negativity was that PD-L1 stained cell accounted for 1% of tumour cells, or tumour and immune cells, assayed by immunohistochemistry staining methods.

RESULTS

4174 patients with advanced or metastatic cancers from eight randomised controlled trials were included in this study. Compared with conventional agents, PD-1 or PD-L1 inhibitors were associated with significantly prolonged overall survival in both patients that were PD-L1 positive (n=2254, hazard ratio 0.66, 95% confidence interval 0.59 to 0.74) and PD-L1 negative (1920, 0.80, 0.71 to 0.90). However, the efficacies of PD-1 or PD-L1 blockade treatment in patients that were PD-L1 positive and PD-L1 negative were significantly different (P=0.02 for interaction). Additionally, in both patients that were PD-L1 positive and PD-L1 negative, the long term clinical benefits from PD-1 or PD-L1 blockade were observed consistently across interventional agent, cancer histotype, method of randomisation stratification, type of immunohistochemical scoring system, drug target, type of control group, and median follow-up time.

CONCLUSIONS

PD-1 or PD-L1 blockade therapy is a preferable treatment option over conventional therapy for both patients that are PD-L1 positive and PD-L1 negative. This finding suggests that PD-L1 expression status alone is insufficient in determining which patients should be offered PD-1 or PD-L1 blockade therapy.

Predictive potential and need for standardization of PD-L1 immunohistochemistry

Checkpoint inhibitors targeting the PD-1/PD-L1 axis are a promising treatment option in several tumor types. PD-L1 expression detected by immunohistochemistry is the first clinically validated predictive biomarker for response to PD-1/PD-L1 inhibitors, though its predictive value varies significantly between tumor types. With the approval of pembrolizumab monotherapy for treatment-naïve, advanced non-small cell lung cancer, PD-L1 testing has to become broadly available in pathology laboratories. When PD-L1 testing started to be introduced in routine pathology practice, there were several open issues, which needed to be addressed in order to provide accurate results. This review will discuss the complex biological background of PD-L1 as predictive biomarker, summarize relevant clinical trials in NSCLC illustrating the origin of different PD-L1 expression cutoffs and scorings, and address issues important for PD-L1 testing including the analytical comparability of the different clinical trial-validated PD-L1 immunohistochemistry assays, the potential of laboratory-developed tests, and an overview of the different scoring algorithms.