Third-Line Nivolumab Monotherapy in Recurrent SCLC: CheckMate 032

Nivolumab Monotherapy and Nivolumab Plus Ipilimumab in Recurrent Small Cell Lung Cancer: Results From the CheckMate 032 Randomized Cohort

INTRODUCTION

Nivolumab monotherapy is approved in the United States for third-line or later metastatic small cell lung cancer based on pooled data from nonrandomized and randomized cohorts of the multicenter, open-label, phase 1/2 trial of nivolumab ± ipilimumab (CheckMate 032; NCT01928394). We report updated results, including long-term overall survival (OS), from the randomized cohort.

METHODS

Patients with small cell lung cancer and disease progression after one to two prior chemotherapy regimens were randomized 3:2 to nivolumab 3 mg/kg every 2 weeks or nivolumab 1 mg/kg plus ipilimumab 3 mg/kg every 3 weeks for four cycles followed by nivolumab 3 mg/kg every 2 weeks. Patients were stratified by number of prior chemotherapy regimens and treated until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) by blinded independent central review.

RESULTS

Overall, 147 patients received nivolumab and 96 nivolumab plus ipilimumab. Minimum follow-up for ORR/progression-free survival/safety was 11.9 months (nivolumab) and 11.2 months (nivolumab plus ipilimumab). ORR increased with nivolumab plus ipilimumab (21.9% versus 11.6% with nivolumab; odds ratio: 2.12; 95% confidence interval: 1.06-4.26; p = 0.03). For long-term OS, minimum follow-up was 29.0 months (nivolumab) versus 28.4 months (nivolumab plus ipilimumab); median (95% confidence interval) OS was 5.7 (3.8-7.6) versus 4.7 months (3.1-8.3). Twenty-four-month OS rates were 17.9% (nivolumab) and 16.9% (nivolumab plus ipilimumab). Grade 3 to 4 treatment-related adverse event rates were 12.9% (nivolumab) versus 37.5% (nivolumab plus ipilimumab), and treatment-related deaths were n =1 versus n = 3, respectively.

CONCLUSIONS

Whereas ORR (primary endpoint) was higher with nivolumab plus ipilimumab versus nivolumab, OS was similar between groups. In each group, OS remained encouraging with long-term follow-up. Toxicities were more common with combination therapy versus nivolumab monotherapy.

Making Checkpoint Inhibitors Part of Treatment of Patients With Locally Advanced Lung Cancers: The Time Is Now

The PACIFIC trial of durvalumab administered for 1 year to patients with stage III lung cancers has set a new standard of care. PACIFIC established the role of immune checkpoint inhibitors (ICIs) for individuals with inoperable and unresectable locally advanced lung cancers that achieve disease control from concurrent chemoradiation. For patients with resectable and operable disease, ICIs administered before surgery, either alone (JHU/MSK, LCMC3, and NEOSTAR) or in combination with chemotherapy (Columbia/MGH and NADIM), have yielded high rates of major pathologic response in resection specimens, an outcome measure that correlates with improved progression-free survival and overall survival. These results have brought forth the dilemma of how to choose the optimal local therapy-either definitive concurrent chemoradiation or surgery-to use with an ICI for patients with stage III lung cancers that are both operable and resectable. Here, we review the data that support the use of each local therapy. Recent successes have also raised the possibility that using ICIs in patients with earlier stages of lung cancer will enhance curability. Randomized trials are underway; however, until they read out, physicians must choose between local and systemic therapies on the basis of the information we have today. Research demonstrates that using surgery, radiation, chemotherapy, and ICIs improve all efficacy outcomes and curability. All modalities should be considered in every patient with locally advanced lung cancer. It is imperative that a multimodality discussion that includes the possible addition of ICIs takes place to choose the best modality and sequence of therapies for each patient.

Efficacy, Safety, and Biomarkers of Toripalimab in Patients with Recurrent or Metastatic Neuroendocrine Neoplasms: A Multiple-Center Phase Ib Trial

PURPOSE

Patients with recurrent or metastatic neuroendocrine neoplasms (NEN) had a poor prognosis and few treatment options. Toripalimab, a humanized IgG4 antibody specific for human PD-1 receptor, was first approved to treat second-line metastatic melanoma in China in 2018.

PATIENTS AND METHODS

The multiple-center phase Ib trial enrolled patients with NENs (Ki-67 ≥ 10%) after failure of first-line therapy received 3 mg/kg toripalimab once every two weeks. The primary objective was objective response rate (ORR) and safety. PD-L1 expression and whole-exome sequencing were performed on tumor biopsies. Secondary objectives included duration of response (DOR), disease control rate (DCR), and progression-free survival and overall survival.

RESULTS

Of 40 patients included from April 2017 to December 2018, 8 partial responses and 6 stable diseases were observed, for a 20% ORR and a 35% DCR. The median DOR was 15.2 months. Patients with PD-L1 expression (≥10%) or high tumor mutational burden (TMB) had better ORR than PD-L1 <10% (50.0% vs. 10.7%, P = 0.019) and TMB-low patients (75.0% vs. 16.1%, P = 0.03). Three of 8 (37.5%) responders harbored ARID1A mutations, whereas only 1 of 27 nonresponders had mutations (P = 0.03). Of note, 1 exceptional responder with TMB-L, microsatellite stable (MSS), and PD-L1-negative had multiple genomic arrangements with high prediction score for neoantigens.

CONCLUSIONS

Toripalimab had antitumor activity and safety in treating recurrent or metastatic NENs. Patients with positive PD-L1 expression, TMB-H (top 10%), and/or microsatellite instable (MSI-H) might preferentially benefit from the treatment. The genomic mutation of ARID1A and high genomic rearrangements might be correlated with clinical benefit.

18F-fluorothymidine (FLT)-PET and diffusion-weighted MRI for early response evaluation in patients with small cell lung cancer: a pilot study

Background

Small cell lung cancer (SCLC) is an aggressive cancer often presenting in an advanced stage and prognosis is poor. Early response evaluation may have impact on the treatment strategy.

Aim

We evaluated ¹⁸F-fluorothymidine-(FLT)-PET/diffusion-weighted-(DW)-MRI early after treatment start to describe biological changes during therapy, the potential of early response evaluation, and the added value of FLT-PET/DW-MRI.

Methods

Patients with SCLC referred for standard chemotherapy were eligible. FLT-PET/DW-MRI of the chest and brain was acquired within 14 days after treatment start. FLT-PET/DW-MRI was compared with pretreatment FDG-PET/CT. Standardized uptake value (SUV), apparent diffusion coefficient (ADC), and functional tumor volumes were measured. FDG-SUV_peak, FLT-SUV_peak, and ADC_median; spatial distribution of aggressive areas; and voxel-by-voxel analyses were evaluated to compare the biological information derived from the three functional imaging modalities. FDG-SUV_peak, FLT-SUV_peak, and ADC_median were also analyzed for ability to predict final treatment response.

Results

Twelve patients with SCLC completed FLT-PET/MRI 1–9 days after treatment start. In nine patients, pretreatment FDG-PET/CT was available for comparison. A total of 16 T-sites and 12 N-sites were identified. No brain metastases were detected. FDG-SUV_peak was 2.0–22.7 in T-sites and 5.5–17.3 in N-sites. FLT-SUV_peak was 0.6–11.5 in T-sites and 1.2–2.4 in N-sites. ADC_median was 0.76–1.74 × 10^− 3 mm²/s in T-sites and 0.88–2.09 × 10⁻³ mm²/s in N-sites. FLT-SUV_peak correlated with FDG-SUV_peak, and voxel-by-voxel correlation was positive, though the hottest regions were dissimilarly distributed in FLT-PET compared to FDG-PET. FLT-SUV_peak was not correlated with ADC_median, and voxel-by-voxel analyses and spatial distribution of aggressive areas varied with no systematic relation. LT-SUV_peak was significantly lower in responding lesions than non-responding lesions (mean FLT-SUV_peak in T-sites: 1.5 vs. 5.7; p = 0.007, mean FLT-SUV_peak in N-sites: 1.6 vs. 2.2; p = 0.013).

Conclusions

FLT-PET and DW-MRI performed early after treatment start may add biological information in patients with SCLC. Proliferation early after treatment start measured by FLT-PET is a promising predictor for final treatment response that warrants further investigation.

Trial registration

Clinicaltrials.gov, NCT02995902. Registered 11 December 2014 - Retrospectively registered.

Development of de novo psoriasis during nivolumab therapy in a patient with small cell lung cancer

INTRODUCTION

The immune checkpoint inhibitors recently entered to small cell lung cancer (SCLC) stage, firstly in the third and recently in the first lines of therapy. This efficacy comes at the expense of many toxicities including skin toxicity. This toxicity is usually in the form of rash and pruritis; however, rare reactions like psoriasis can also be seen.

CASE REPORT

Herein, we report an SCLC case who developed de novo psoriasis while treated with nivolumab as the third-line treatment for SCLC.

MANAGEMENT AND OUTCOME

The psoriatic plaques were regressed with the topical highly potent steroid therapy, and immunotherapy was continued without further complications.

DISCUSSION

We think that rare adverse events like de novo psoriasis are important considering the expanding role of these agents; their timely recognition and treatment are important in the management of cancer patients.

PD-1 disrupted CAR-T cells in the treatment of solid tumors: Promises and challenges

Unprecedented efficacy of chimeric antigen receptor (CAR) T cell therapy in the treatment of hematologic malignancies brings new hope for patients with many cancer types including solid tumors. However, the challenges for CAR-T cell therapy in eradicating solid tumors are immense. To overcome these seemingly intractable hurdles, more "powerful" CAR-T cells with enhanced antitumor efficacy are required. Emerging data support that the anti-tumor activity of CAR-T cells can be enhanced significantly without evident toxicity through simultaneous PD-1 disruption by genome editing. This review focuses on the current progress of PD-1 gene disrupted CAR-T cells in cancer therapy. Here we discuss key rationales for this new combination strategy and summarize the available pre-clinical studies. An update is provided on human clinical studies and available registered cancer clinical trials using CAR-T cells with PD-1 disruption. Future prospects and challenges are also discussed.

Immunotherapy in Lung Cancer: From a Minor God to the Olympus

Over the last decade, we have witnessed a paradigm shift in cancer treatment, with the advent of novel therapeutic approaches that target or manipulate the immune system, also known as immunotherapy. Blocking immune checkpoints has emerged as an effective strategy with unprecedented results in several solid tumors, including lung cancer. Since 2012 when PD(L)-1 inhibitors showed first clinical signals of activity in lung cancer, immune checkpoint blockade (ICB) has emerged as a novel effective therapeutic strategy in different settings, determining a dramatic change in the therapeutic landscape of both non-small cell lung cancer (NSCLC) and, more recently, small cell lung cancer (SCLC). Although the benefit from this novel therapeutic approach is undeniable, several open questions still remain unanswered. Herein, we summarize the major breakthroughs in the immunotherapy journey in lung cancer and how it is changing our clinical practice.

Pembrolizumab After Two or More Lines of Previous Therapy in Patients With Recurrent or Metastatic SCLC: Results From the KEYNOTE-028 and KEYNOTE-158 Studies

INTRODUCTION

Pembrolizumab has shown clinical benefit in patients with previously treated recurrent or metastatic SCLC in the phase 1b multicohort study KEYNOTE-028 (NCT02054806) and the phase 2 multicohort study KEYNOTE-158 (NCT02628067). We present a pooled analysis of patients from KEYNOTE-028 and KEYNOTE-158 who had received two or more lines of previous therapy for SCLC.

METHODS

Eligible patients were aged 18 years and above, had histologically or cytologically confirmed incurable recurrent or metastatic SCLC, had an Eastern Cooperative Oncology Group performance status of 1 and below, and had received two or more lines of previous therapy. Patients in KEYNOTE-028 were required to have a programmed death ligand 1 (PD-L1)-positive tumor. Patients received pembrolizumab (10 mg/kg every 2 weeks in KEYNOTE-028 or 200 mg every 3 weeks in KEYNOTE-158) for up to 2 years. The primary end point was objective response rate per Response Evaluation Criteria in Solid Tumors version 1.1, which is presented here per independent review.

RESULTS

Eighty-three patients who had received two or more lines of previous therapy (KEYNOTE-028, n = 19; KEYNOTE-158, n = 64) were included. Median follow-up duration was 7.7 (range, 0.5-48.7) months. Objective response rate was 19.3% (95% confidence interval: 11.4-29.4); two patients had complete response (one with a PD-L1-positive tumor), and 14 patients had partial response (13 with PD-L1-positive tumors). The median duration of response was not reached (range, 4.1‒35.8+ mo; plus sign indicates ongoing response); 61% of responders had responses lasting 18 months or longer. Fifty-one patients (61.4%) experienced any-grade treatment-related adverse events; eight patients (9.6%) had grade 3 or higher events.

CONCLUSIONS

Pembrolizumab exhibited durable antitumor activity in a subset of patients with recurrent or metastatic SCLC who had undergone two or more previous lines of therapy, regardless of PD-L1 expression. Pembrolizumab was well tolerated.

Characterization of PD-L1 protein expression and CD8+ tumor-infiltrating lymphocyte density, and their associations with clinical outcome in small-cell lung cancer

Background

This study aimed to characterize programmed death ligand-1 (PD-L1) expression and CD8⁺ tumor-infiltrating lymphocytes (TILs) density, and their impact on survival in patients with surgically resected small-cell lung cancer (SCLC).

Methods

Fifty-six patients with surgically resected SCLC were included. PD-L1 protein expression and CD8⁺ TILs were tested by immunohistochemistry. A meta-analysis of 15 articles with 1,505 patients that investigated the prevalence and prognostic significance of PD-L1 expression in SCLC was conducted.

Results

Twenty-two (39.3%) patients had positive PD-L1 protein expression and 42 (75.0%) had high CD8⁺ TILs density. PD-L1 expression level was not associated with CD8⁺ TILs density (P=0.528). No any association between clinicopathological features and PD-L1 expression level or CD8⁺ TILs density was observed. Positive PD-L1 expression [hazard ratio (HR) =0.374, P=0.002] and high CD8⁺ TILs density (HR =0.429, P=0.008) were independently associated with significantly longer overall survival (OS), which remain the statistical significance in multivariate analyses (P=0.007, P=0.002; respectively). Meta-analysis showed that the prevalence of positive PD-L1 expression was 0.35 [95% confidence interval (CI), 0.22-0.48] and positive PD-L1 expression was correlated with markedly longer OS (HR =0.61; 95% CI, 0.31-0.91) in patients with SCLC.

Conclusions

The prevalence of PD-L1 expression in surgically resected SCLC is lower than that published for NSCLC. There was no association between PD-L1 expression or CD8⁺ TILs density and clinicopathological parameters. PD-L1 expression and CD8⁺ TILs density was independently correlated with better outcome in patients with SCLC.

[Progress on PD-1/PD-L1 Checkpoint Inhibitors in Lung Cancer]

In recent years, research on immunotherapy has made great progress. Currently, immunotherapy has made significant breakthrough, especially programmed death 1/programmed death-ligand 1 (PD-1/PD-L1) checkpoint inhibitors (e.g, Nivolumab, Pembrolizumab, Atezolizumab, Durvalumab and Avelumab, etc.) have brought clinical benefits to patients with various pathological types of lung cancer, including squamous cell carcinoma, adenocarcinoma and small cell lung cancer. In this paper, the application value and current status of PD-1/PD-L1 checkpoint inhibitors in lung cancer were comprehensively analyzed by reviewing and interpreting representative clinical studies. Based on the results of various large-scale clinical trials results, the indications of immunotherapy in lung cancer have been continuously broadened, and the details of immunotherapy have also been constantly optimized. However, immunotherapy still faces many challenges, such as the selection of immune combination strategies, the exploration of biomarkers, the management of adverse events, the feasibility of application of driver gene mutation population and so on. In this article, we made a systematic review about the latest progress of PD-1/PD-L1 checkpoint inhibitors in lung cancer, in order to provide cutting-edge reference for the clinical workers.
.

Prevalence of DLL3, CTLA-4 and MSTN Expression in Patients with Small Cell Lung Cancer

Introduction

Immune-based and antibody-drug conjugate therapies have shown promise in the treatment of patients with small cell lung cancer (SCLC). However, better predictive biomarkers are needed for selection of the appropriate SCLC patients for these advanced therapies and also for evaluation of the efficacy of these treatments.

Objective

The aim of this study was to examine the expression of delta-like protein 3 (DLL3), cytotoxic T lymphocyte-associated protein 4 (CTLA-4), and mesothelin (MSTN) in patients with SCLC and compare them with those patients’ clinical characteristics.

Methods

Immunohistochemical analyses of DLL3, CTLA-4 and MSTN expression were performed in 38 samples from patients with SCLC.

Results

We found that positive expression in patients of the biomarkers was as follows: for DLL3, 100% (38/38), for CTLA-4, 89.5% (36/38) and for MSTN 81.5% (31/38). The median survival time was 17.9 months in the DLL3 high expression group and 23 months in the DLL3 low expression group. Patients with a high expression of DLL3 showed a poorer prognosis than those with a low expression of DLL3 (HR=3.4; 95% CI, 1.34–8.6; p=0.01).

Conclusion

The expression of DLL3, CTLA-4 and MSTN was not correlated with patients’ age, sex, smoking status, stage, and tumor metastasis. The fact that there was a higher expression of DLL3, CTLA-4, and MSTN in SCLC suggested that these molecules could be used as predictive biomarkers for SCLC.

Immune checkpoint inhibitors win the 2018 Nobel Prize

The 2018 Nobel Prize in Physiology or Medicine was awarded to Tasuku Honjo and James Allison for their discoveries in cancer immunology. Professor Honjo was awarded due to his discovery of the programmed death molecule-1 (PD-1) on T cells. Professor Allison discovered another important immunosuppressive molecule: cytotoxic T-lymphocyte antigen-4 (CTLA-4). Suppression of T cell activation by PD-1 and/or CTLA-4 is considered one of the major escape mechanisms of cancer cells. Inhibition of these molecules by immune checkpoint inhibitors can successfully activate the immune system to fight cancer. Checkpoint inhibitors have brought about a major breakthrough in cancer immunotherapy, reviving the hope of curing patients with end-stage cancer, including a wide variety of cancer types. In metastatic malignant melanoma, the previous long-term survival of only 5% can now be extended to 50% with anti-PD-1 plus anti-CTLA-4 combined treatment in the latest report. More checkpoint molecules such as lymphocyte-activation gene 3 and T cell immunoglobulin and mucin domain 3 are under investigation. The achievement of Drs. Honjo and Allison in cancer immunotherapy has encouraged research into other immune-pathological diseases.

Nivolumab for the treatment of small cell lung cancer

Introduction: Treatment of extensive-stage SCLC is still a challenge but immunotherapy with checkpoint inhibitors is showing promising results. Nivolumab alone or in combination with ipilimumab has demonstrated a benefit in terms of response and survival in patients with pre-treated extensive-stage disease and has been approved as third-line therapy after failure of chemotherapy. However, data from two phase III trials with nivolumab are negative. In the first trial, nivolumab was administered as a single agent compared to second-line chemotherapy, while in the second it was given alone or in combination with ipilimumab as maintenance treatment after platinum-based chemotherapy.Areas covered: Our review focuses on the role of immunotherapy, and in particular nivolumab, in the treatment of SCLC, describing the results of the main trials and its future perspectives, with reference to clinical trials with other checkpoint inhibitors.Expert opinion: The future of nivolumab in the treatment of SCLC needs to be clarified with further clinical trials, in which improved patient selection and a more specific setting and/or timepoint of the disease may be identified.

Transformation to small cell lung cancer as a mechanism of resistance to immunotherapy in non-small cell lung cancer

OBJECTIVES

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death world-wide. Immune checkpoint inhibitors (ICI) have become the most promising type of treatment in oncology in general, and significantly so in NSCLC. Limited data is available about mechanisms of primary resistance. Data is lacking about mechanisms involved in acquired resistance or mixed responses in NSCLC. We aimed to identify mechanisms of resistance by studying biopsies taken from sites of secondary progression.

MATERIALS AND METHODS

We identified all cases of NSCLC that have received ICI for advanced disease in our institute. Of these cases, those that have demonstrated acquired resistance or mixed responses, and have underwent a biopsy from a progressive lesion were analyzed. Selected specimens were subjected to next-generation sequencing (NGS; Oncomine™ Solid Tumour Fusion Transcript Kit).

RESULTS

Out of 664 lung cancer cases, 249 were NSCLC that have received ICI. Of these, eight cases matched our search criteria. Two of them demonstrated transformation to small cell lung cancer (SCLC; 2/8, 25%). NGS verified a common origin to a matched pre-treatment NSCLC specimen and an on-treatment progressive SCLC specimen. In two cases no tumor cells were found and in the remaining four the pathology was similar to the initial biopsy. In one of the cases of SCLC transformation platinum-etoposide chemotherapy was administered, with short-term benefit only and further disease progression.

CONCLUSION

Mechanisms of acquired resistance to ICI include SCLC transformation. Repeat biopsies of progressing lesions after initial response or in cases of mixed response can shed light on mechanisms of resistance.

Combination Olaparib and Temozolomide in Relapsed Small-Cell Lung Cancer

Small-cell lung cancer (SCLC) is an aggressive malignancy in which inhibitors of PARP have modest single-agent activity. We performed a phase I/II trial of combination olaparib tablets and temozolomide (OT) in patients with previously treated SCLC. We established a recommended phase II dose of olaparib 200 mg orally twice daily with temozolomide 75 mg/m² daily, both on days 1 to 7 of a 21-day cycle, and expanded to a total of 50 patients. The confirmed overall response rate was 41.7% (20/48 evaluable); median progression-free survival was 4.2 months [95% confidence interval (CI), 2.8-5.7]; and median overall survival was 8.5 months (95% CI, 5.1-11.3). Patient-derived xenografts (PDX) from trial patients recapitulated clinical OT responses, enabling a 32-PDX coclinical trial. This revealed a correlation between low basal expression of inflammatory-response genes and cross-resistance to both OT and standard first-line chemotherapy (etoposide/platinum). These results demonstrate a promising new therapeutic strategy in SCLC and uncover a molecular signature of those tumors most likely to respond. SIGNIFICANCE: We demonstrate substantial clinical activity of combination olaparib/temozolomide in relapsed SCLC, revealing a promising new therapeutic strategy for this highly recalcitrant malignancy. Through an integrated coclinical trial in PDXs, we then identify a molecular signature predictive of response to OT, and describe the common molecular features of cross-resistant SCLC.See related commentary by Pacheco and Byers, p. 1340.This article is highlighted in the In This Issue feature, p. 1325.

Efficacy and Safety of Rovalpituzumab Tesirine in Third-Line and Beyond Patients with DLL3-Expressing, Relapsed/Refractory Small-Cell Lung Cancer: Results From the Phase II TRINITY Study

PURPOSE

Although extensive-stage small-cell lung cancer (SCLC) is highly responsive to first-line therapy, virtually all patients develop resistance with short survival. Rovalpituzumab tesirine (Rova-T) is an antibody-drug conjugate targeting delta-like 3 protein (DLL3). This open-label, single-arm, phase II study (TRINITY) assessed safety and efficacy of Rova-T in patients with DLL3-expressing SCLC in the third-line and beyond (3L+) setting.

PATIENTS AND METHODS

Patients with DLL3-expressing SCLC (determined by mouse antibody immunohistochemistry [IHC] assay), and ≥2 prior regimens, received 0.3 mg/kg Rova-T once every 6 weeks for two cycles. During study, a rabbit antibody IHC assay was developed and used for the final analysis, with DLL3-positive and DLL3-high defined as ≥25% and ≥75% of tumor cells positive for DLL3, respectively. The primary endpoints were objective response rate (ORR) and overall survival (OS).

RESULTS

Among 339 patients enrolled, 261 (77%) had two prior lines of therapy and 78 (23%) had ≥3. DLL3-high and DLL3-positive tumors by rabbit IHC were seen in 238 (70%) and 287 (85%) patients, respectively. The remaining 52 (15%) were DLL3-negative only by rabbit IHC or had missing results. ORR was 12.4%, 14.3%, and 13.2% in all, DLL3-high, and DLL3-positive patients, respectively. Median OS was 5.6 months in all patients and 5.7 months in DLL3-high patients. The most common adverse events (AE) were fatigue, photosensitivity reaction, and pleural effusion. Grade 3-5 AEs were seen in 213 (63%) patients.

CONCLUSIONS

Rova-T is the first targeted agent in SCLC to use DLL3, a novel biomarker. However, results demonstrate modest clinical activity in 3L+ SCLC, with associated toxicities.

Immune checkpoint blockade in small cell lung cancer

Despite the highly immunogenic potential of small cell lung cancer (SCLC), progress in evaluating the therapeutic value of immune checkpoint agents has lagged behind that of non-small cell lung cancer. Results from a number of phase I-III clinical trials that specifically address the use of anti-PD-1, anti-PD-L1 and anti-CTLA-4 agents in SCLC have now been reported. This review will focus on the available evidence for immune checkpoint blockade in SCLC and review current biomarker strategies with the aim of providing perspective and interpretation of this data for clinical practice.

Imaging of Precision Therapy for Lung Cancer: Current State of the Art

Advances in characterization of molecular and genomic abnormalities specific to lung cancer have made precision therapy the current standard of care for lung cancer treatment. This article will provide a cutting-edge review of imaging of lung cancer in the current era of precision medicine. The focus of the article includes (a) an update on the recent advances in precision therapy for non-small cell lung cancer and their implications on imaging; (b) molecular and genomic biomarkers and pitfalls of image interpretations for lung cancer precision therapy; and (c) review of the current approaches and future directions of precision imaging for lung cancer, emphasizing emerging observations in longitudinal tumor kinetics, radiomics, and molecular and functional imaging. The article is designed to help radiologists to remain up to date in the rapidly evolving world of lung cancer therapy and serve as key members of multidisciplinary teams caring for these patients.

Immune Checkpoint Inhibitors in Small Cell Lung Cancer: A Partially Realized Potential

Small cell lung cancer (SCLC) is a highly lethal subtype of lung cancer that has seen few therapeutic advances, despite ongoing concerted efforts. Immunotherapy has been an effective option in other carcinogen-related cancers and has shown modest activity in SCLC. Monotherapy with the anti-PD-1 antibody nivolumab in patients with at least two prior lines of therapy was associated with a response rate of 11.9% and a median duration of response of 17.9 months, leading to accelerated approval by the Food and Drug Administration (FDA) as third-line therapy for SCLC. Second-line checkpoint inhibitors have not performed well enough to change the standard of care, and maintenance immunotherapy has not shown significant benefit. However, the incorporation of concurrent immunotherapy in the first-line treatment of SCLC has improved outcomes. The addition of the anti-PD-L1 antibody atezolizumab to standard carboplatin plus etoposide led to an improvement in progression free survival (PFS) and overall survival, the first such improvement in over 30 years leading to the approval of atezolizumab as part of first-line therapy for advanced SCLC. While these landmark approvals offer promising novel treatment options for this recalcitrant disease, more work is needed to optimize their delivery and to build upon these important advances.

Real-world effectiveness and tolerability of small-cell lung cancer (SCLC) treatments: A systematic literature review (SLR)

OBJECTIVES

SCLC makes up approximately 15% of all lung carcinomas and is characterized by relatively aggressive spread and poorer prognosis compared to other lung cancers. Treatment options are limited, and their efficacy in randomized trials is poor, whilst outcomes in clinical practice remain unclear. The aim of this study was to assess the real-world effectiveness and tolerability of SCLC treatments.

METHODS

An SLR was conducted across nine databases accessed through OVID, capturing observational, non-randomized studies published between 01/2006-11/2018. In total, 554 abstracts were retrieved and systematically screened for eligibility. The eligible publications included effectiveness and tolerability data from adult SCLC patients (at any line of therapy). Additional grey literature searches were conducted.

RESULTS

Forty-three publications were included in this review-data from first-line therapies were captured most often (n = 32), while data from second (n = 14) and third line (n = 7) and beyond (n = 7) were less frequent. The publications reported primarily on chemotherapy/radiotherapy. The majority of publications lacked robustness and only 14/43 conducted statistical analyses or controlled for bias. Median OS for the largest SCLC populations were 9.6 months at first line (n = 23,535) and 4.9 months at second line (n = 254) for treatment with chemotherapy, and 4.7 months at third line (n = 120) for predominantly platinum-based chemotherapy or cyclophosphamide/adriamycin/vincristine. Hematologic toxicities (such as neutropenia, thrombocytopenia and anemia) were the most frequently reported TRAEs (n = 9).

CONCLUSIONS

Real-world treatment effectiveness and tolerability data were fragmented and inconsistently reported, and available publications were primarily of poor quality and lacked statistical analyses. This SLR showed limited treatment options and poor OS in SCLC, with no treatment option being clearly superior. TRAEs additionally increased the burden of this already challenging disease. Recent data suggest real-world outcomes are even poorer that those reported in clinical trials, and that novel therapies are needed to offer new treatment options for patients.

Immunotherapy for skin cancer

Among all tumor types, skin cancers are profoundly sensitive to immunotherapy. Indeed, the recently reported response rates for anti-PD-1 (anti-programmed-death 1) therapy for cutaneous malignant melanomas (MM), Merkel cell carcinomas, basal cell carcinomas, cutaneous squamous cell carcinomas and Kaposi sarcomas are all above 40%. This unique immunogenicity renders skin cancers as a paradigm for tumor-immune interactions and is driven by high mutational burdens, over-expressed tumor antigens and/or viral antigens. However, despite the clear demonstration of immunologic cure of skin cancer in some patients, most tumors develop either early (primary) or late (adaptive) resistance to immunotherapy. Resistance mechanisms are complex, and include contributions of tumor cell-intrinsic, T cell and microenvironment factors that have been recently further elucidated with the advent of single-cell technologies. This review will focus on the exciting progress with immunotherapy for skin cancers to date, and also our current understanding of the mechanisms of resistance to immunotherapy.

Treatment-Related Adverse Events of PD-1 and PD-L1 Inhibitors in Clinical Trials: A Systematic Review and Meta-analysis

IMPORTANCE

Programmed cell death (PD-1) and programmed cell death ligand 1 (PD-L1) inhibitors have been increasingly used in cancer therapy. Understanding the treatment-related adverse events of these drugs is critical for clinical practice.

OBJECTIVE

To evaluate the incidences of treatment-related adverse events of PD-1 and PD-L1 inhibitors and the differences between different drugs and cancer types.

DATA SOURCES

PubMed, Web of Science, Embase, and Scopus were searched from October 1, 2017, through December 15, 2018.

STUDY SELECTION

Published clinical trials on single-agent PD-1 and PD-L1 inhibitors with tabulated data on treatment-related adverse events were included.

DATA EXTRACTION AND SYNTHESIS

Trial name, phase, cancer type, PD-1 and PD-L1 inhibitor used, dose escalation, dosing schedule, number of patients, number of all adverse events, and criteria for adverse event reporting data were extracted from each included study, and bayesian multilevel regression models were applied for data analysis.

MAIN OUTCOMES AND MEASURES

Incidences of treatment-related adverse events and differences between different drugs and cancer types.

RESULTS

This systematic review and meta-analysis included 125 clinical trials involving 20 128 patients; 12 277 (66.0%) of 18 610 patients from 106 studies developed at least 1 adverse event of any grade (severity), and 2627 (14.0%) of 18 715 patients from 110 studies developed at least 1 adverse event of grade 3 or higher severity. The most common all-grade adverse events were fatigue (18.26%; 95% CI, 16.49%-20.11%), pruritus (10.61%; 95% CI, 9.46%-11.83%), and diarrhea (9.47%; 95% CI, 8.43%-10.58%). The most common grade 3 or higher adverse events were fatigue (0.89%; 95% CI, 0.69%-1.14%), anemia (0.78%; 95% CI, 0.59%-1.02%), and aspartate aminotransferase increase (0.75%; 95% CI, 0.56%-0.99%). Hypothyroidism (6.07%; 95% CI, 5.35%-6.85%) and hyperthyroidism (2.82%; 95% CI, 2.40%-3.29%) were the most frequent all-grade endocrine immune-related adverse events. Nivolumab was associated with higher mean incidences of all-grade adverse events compared with pembrolizumab (odds ratio [OR], 1.28; 95% CI, 0.97-1.79) and grade 3 or higher adverse events (OR, 1.30; 95% CI, 0.89-2.00). PD-1 inhibitors were associated with a higher mean incidence of grade 3 or higher adverse events compared with PD-L1 inhibitors (OR, 1.58; 95% CI, 1.00-2.54).

CONCLUSIONS AND RELEVANCE

Different PD-1 and PD-L1 inhibitors appear to have varying treatment-related adverse events; a comprehensive summary of the incidences of treatment-related adverse events in clinical trials provides an important guide for clinicians.

DLL3: an emerging target in small cell lung cancer

Small cell lung cancer (SCLC) accounts for approximately 15% of all lung cancers. Despite high rates of response to first-line chemotherapy and radiotherapy, patients with extensive-stage disease eventually relapse, and very few patients survive more than 5 years from diagnosis. Treatment options for recurrent or refractory disease are limited, and the treatments that do exist are associated with significant treatment-related toxicities. Delta-like ligand 3 (DLL3) is an inhibitory Notch ligand that is highly expressed in SCLC and other neuroendocrine tumors but minimally expressed in normal tissues. It is therefore being explored as a potential therapeutic target in SCLC. Here, we review the preclinical and clinical evidence for targeting DLL3 in SCLC and discuss several DLL3-specific therapies being developed for the treatment of SCLC: the antibody-drug conjugate rovalpituzumab tesirine, the bispecific T cell engager immuno-oncology therapy AMG 757, and the chimeric antigen receptor T cell therapy AMG 119.

Immune checkpoint inhibitors for small cell lung cancer: opportunities and challenges

Lung cancer is the most common cancer and the leading cause of cancer death worldwide, with an estimated 2.1 million new cases and 1.8 million deaths in 2018. Although small cell lung cancer (SCLC) is the most aggressive type of lung cancer, it shows high response rates to chemotherapy in early lines of therapy. Unfortunately, it is associated with rapid recurrence and relatively poor prognosis. Over the last few years, considerable progress has been made in cancer immunotherapy. One of the most promising ways to activate therapeutic antitumor immunity is via blockade of immune checkpoints, such as cytotoxic T lymphocyte-associated protein-4 (CTLA-4) and programmed cell death protein-1/programmed cell death ligand-1 (PD-1/PD-L1). Immune checkpoint inhibitors show promise as SCLC therapeutics. The overall expectation for immuno-oncology is high, and the outcomes of trials will hopefully reveal a variety of treatment options for SCLC patients. In this review, we discuss the discovery of new immune inhibitory and stimulatory pathways and rational combination strategies to explain the role of immunotherapy in SCLC and its future opportunities and challenges.

Immunotherapy in Small Cell Lung Cancer

Small-cell lung cancer (SCLC) is extremely sensitive to standard treatments, including conventional cytotoxic chemotherapies and radiotherapy, and has poor prognosis and short survival. Standard therapies have reached a plateau of effectiveness and new therapeutic strategies are needed to improve SCLC patient outcomes going forward. Immunotherapy has revolutionised the treatment of solid malignancies, offering a novel way to harness the host immune system to target malignant cells in patients whose disease may no longer respond to cytotoxic therapy. This review describes the available data for the checkpoint inhibitors, such as anti-cytotoxic T-lymphocyte antigen-4 protein (CTLA-4), anti-programmed cell death-1 protein receptor (PD-1), and ligands (PD-L1 and PD-L2) alone or in combination with first-line chemotherapy or in relapsed SCLC. Several trials investigating immunotherapy in SCLC patients are ongoing and the results are awaited soon. Moreover, further immune checkpoint inhibitors directed against other targets, such as the killer-cell immunoglobulin-like receptor and lymphocyte-activation gene-3, are in clinical development. Overall, the high expectations from the oncology community are that the drugs under development will offer new and improved treatment options for SCLC patients.

Future Options of Molecular-Targeted Therapy in Small Cell Lung Cancer

Lung cancer is the leading cause of cancer-related deaths worldwide. With a focus on histology, there are two major subtypes: Non-small cell lung cancer (NSCLC) (the more frequent subtype), and small cell lung cancer (SCLC) (the more aggressive one). Even though SCLC, in general, is a chemosensitive malignancy, relapses following induction therapy are frequent. The standard of care treatment of SCLC consists of platinum-based chemotherapy in combination with etoposide that is subsequently enhanced by PD-L1-inhibiting atezolizumab in the extensive-stage disease, as the addition of immune-checkpoint inhibition yielded improved overall survival. Although there are promising molecular pathways with potential therapeutic impacts, targeted therapies are still not an integral part of routine treatment. Against this background, we evaluated current literature for potential new molecular candidates such as surface markers (e.g., DLL3, TROP-2 or CD56), apoptotic factors (e.g., BCL-2, BET), genetic alterations (e.g., CREBBP, NOTCH or PTEN) or vascular markers (e.g., VEGF, FGFR1 or CD13). Apart from these factors, the application of so-called 'poly-(ADP)-ribose polymerases' (PARP) inhibitors can influence tumor repair mechanisms and thus offer new perspectives for future treatment. Another promising therapeutic concept is the inhibition of 'enhancer of zeste homolog 2' (EZH2) in the loss of function of tumor suppressors or amplification of (proto-) oncogenes. Considering the poor prognosis of SCLC patients, new molecular pathways require further investigation to augment our therapeutic armamentarium in the future.

Molecular subtypes of small cell lung cancer: a synthesis of human and mouse model data

Small cell lung cancer (SCLC) is an exceptionally lethal malignancy for which more effective therapies are urgently needed. Several lines of evidence, from SCLC primary human tumours, patient-derived xenografts, cancer cell lines and genetically engineered mouse models, appear to be converging on a new model of SCLC subtypes defined by differential expression of four key transcription regulators: achaete-scute homologue 1 (ASCL1; also known as ASH1), neurogenic differentiation factor 1 (NeuroD1), yes-associated protein 1 (YAP1) and POU class 2 homeobox 3 (POU2F3). In this Perspectives article, we review and synthesize these recent lines of evidence and propose a working nomenclature for SCLC subtypes defined by relative expression of these four factors. Defining the unique therapeutic vulnerabilities of these subtypes of SCLC should help to focus and accelerate therapeutic research, leading to rationally targeted approaches that may ultimately improve clinical outcomes for patients with this disease.

A case of small-cell lung cancer with adrenocorticotropic hormone deficiency induced by nivolumab

Anti-programmed death-1 (anti-PD-1) monoclonal antibodies, such as nivolumab, have been used for the treatment of various types of cancers, and excellent efficacy has been shown in some patients. The adverse effects of anti-PD-1 antibodies relating to autoimmunity are different from traditional chemotherapeutic drugs and may involve many organs including the endocrine system. We herein describe a case of adrenocorticotropic hormone deficiency during the treatment of advanced small-cell lung cancer, probably caused by nivolumab-induced hypophysitis. The case showed nonspecific, insidious, as well as potentially life-threatening characters of immune-related adverse effects. It is important for physicians to acknowledge clinical features of the rare side effect and take appropriate and prompt treatment.

Mechanisms of Resistance to Immune Checkpoint Blockade: Why Does Checkpoint Inhibitor Immunotherapy Not Work for All Patients?

The emergence of immune checkpoint blockade therapies over the last decade has transformed cancer treatment in a wide range of tumor types. Unprecedented and durable clinical responses in difficult-to-treat cancer histologies have been observed. However, despite these promising long-term responses, the majority of patients fail to respond to immune checkpoint blockade, demonstrating primary resistance. Additionally, many of those who initially respond to treatment eventually experience relapse secondary to acquired resistance. Both primary and acquired resistance are a result of complex and constantly evolving interactions between cancer cells and the immune system. Many mechanisms of resistance have been characterized to date, and more continue to be uncovered. By elucidating and targeting mechanisms of resistance, treatments can be tailored to improve clinical outcomes. This review will discuss the landscape of immune checkpoint blockade response data, different resistance mechanisms, and potential therapeutic strategies to overcome resistance.