Response Rate and Survival at Key Timepoints With PD-1 Blockade vs Chemotherapy in PD-L1 Subgroups: Meta-Analysis of Metastatic NSCLC Trials

Background

Expression of programmed cell death ligand 1 (PD-L1) on tumor cells with or without immune cells is widely reported in clinical trials of programmed cell death receptor 1 (PD-1) blockade in metastatic non-small cell lung cancer. Various cutpoints have been studied.

Methods

We performed a systematic search of MEDLINE, EMBASE, and conference proceedings up to December 2019 for randomized and nonrandomized clinical trials of anti-PD-1 or anti-PD-L1 monotherapy in metastatic non-small cell lung cancer. We retrieved data on objective response rate (ORR), 1-year and 2-year progression-free survival (PFS), and 2-year and 3-year overall survival (OS) in various PD-L1 subgroups. Results were pooled and analyzed based on different cutpoints, with nonrandomized comparisons made with pooled chemotherapy outcomes.

Results

A total of 9810 patients in 27 studies were included. In treatment-naïve patients, benefits with PD-1 blockade over chemotherapy were seen in ORR in patients having PD-L1 50% or greater, in 2-year OS for PD-L1 1% or greater, and in 1-year PFS, 2-year PFS, and 3-year OS for unselected patients. First-line PD-1 blockade compared with chemotherapy demonstrated higher ORR, 2-year PFS, and 3-year OS if PD-L1 was 50% or greater; lower ORR, higher 2-year PFS, and similar 3-year OS if PD-L1 was 1%-49%; and lower ORR, similar 1-year PFS, and lower 2-year OS if PD-L1 was less than 1%. In previously treated patients, PD-1 blockade demonstrated similar or superior outcomes to chemotherapy in all PD-L1 subgroups.

Conclusions

PD-L1 should guide the choice of PD-1 blockade vs chemotherapy in treatment-naïve patients. In previously treated patients, PD-1 blockade provides a favorable outcome profile to chemotherapy in all PD-L1 subgroups.

Nivolumab plus ipilimumab for the first-line treatment of metastatic NSCLC

INTRODUCTION

In the last decade, immune checkpoint inhibitors have revolutionized the treatment of several malignancies including non-small cell lung cancer (NSCLC). The inhibition of cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and the programmed death receptor 1 (PD-1) pathways leads to an activation of the immune response against tumor cells. Thanks to a synergistic effect, the combination of the checkpoint inhibitors nivolumab and ipilimumab has the potential to improve outcomes of NSCLC patients.

AREAS COVERED

We provide an overview of clinical trials evaluating the combination of nivolumab and ipilimumab in the first-line treatment of advanced NSCLC patients.

EXPERT OPINION

The combination of nivolumab and ipilimumab, alone or with a few cycles of chemotherapy, was demonstrated to be a valid option for first-line treatment of metastatic NSCLC patients without EGFR mutation and ALK rearrangement. However, a better understanding of patients who can benefit from this approach is required.

Immunotherapy Alone or in Combination with Chemotherapy as First-Line Treatment of Non-Small Cell Lung Cancer

OPINION STATEMENT

Immune checkpoint inhibitors (ICIs) have revolutionized the management of metastatic and selected cases of unresectable advanced non-small cell lung cancer (NSCLC). Importantly for patients, this implies that in the absence of a targetable oncogenic driver [especially epidermal growth factor receptor (EGFR) gene mutations and anaplastic lymphoma kinase (ALK) gene rearrangements] and in the presence of high programmed death-ligand 1 (PD-L1) expression (≥ 50%), they are eligible for mono-therapy with pembrolizumab thereby avoiding chemotherapy as the first line of treatment. This mono-immunotherapy approach for high PD-L1 metastatic NSCLC is associated with improved overall survival (OS) and radiological responses (RR) with lesser toxicity as compared with conventional platinum doublet chemotherapy for both non-squamous and squamous histological types.However, majority of NSCLC patients either have no or low expression of PD-L1 (< 50%) and such patients derive greater benefit from a combination of PD-1/PD-L1 ICIs with platinum doublet chemotherapy as compared with chemotherapy alone. Again, benefits are seen for both OS and RRs. However, combining immunotherapy with chemotherapy, in general, does lead to higher toxicity than those seen with either of the two alone.Additionally, for non-squamous NSCLC patients, clinicians should not initiate ICI treatment till the results of common targetable genetic alterations like EGFR mutation, ALK, and ROS1 gene rearrangement testing are known (preferably on broad next generation sequencing) and are negative (even if results of PD-L1 testing are available)-as targeted therapies remain the cornerstone of treatment for patients harboring these oncogenic drivers.It is worth mentioning that PD-1 and PD-L1 ICIs are very expensive, and their usage is associated with occurrence of immune-related adverse events (irAEs) which occasionally can be severe. Hence, it is important to discuss efficacy, toxicity, and cost-related to ICI treatment with each and every patient at diagnosis in order to help them decide if they are willing to go ahead with this form of therapy either singly (for high PD-L1 expressors) or in combination with chemotherapy (for others).

ICON: a randomized phase IIb study evaluating immunogenic chemotherapy combined with ipilimumab and nivolumab in patients with metastatic hormone receptor positive breast cancer

BACKGROUND

Immunotherapy with checkpoint inhibitors (CPI) targeting PD-1 or CTLA-4 has emerged as an important treatment modality for several cancer forms. In hormone receptor positive breast cancer (HR + BC), this therapeutic approach is largely unexplored. We have started a clinical trial, ICON (CA209-9FN), evaluating CPI combined with selected chemotherapy in patients with metastatic HR + BC. The tumor lymphocyte infiltration is predictive for the effect of chemotherapy in BC. In ICON, we use anthracycline, which are considered as "immunogenic" chemotherapy, and low-dose cyclophosphamide, which has been reported to counter immunosuppressive cells.

METHODS

ICON is a randomized exploratory phase IIb study evaluating the safety and efficacy of combining nivolumab (nivo; anti-PD-1) and ipilimumab (ipi; anti-CTLA-4) with chemotherapy in subjects with metastatic HR + BC. Primary objectives are aassessment of toxicity and progression-free survival. The trial will enrol 75 evaluable subjects, randomized 2:3 into two arms (A:B). Patients in Arm A receive only chemotherapy, i.e. pegylated liposomal doxorubicin (PLD 20 mg/m² intravenously every 2nd week) + cyclophosphamide (cyclo; 50 mg per day, first 2 weeks in each 4 week cycle). Patients in Arm B receive PLD + cyclo + ipilimumab (1 mg intravenously every 6th week) + nivolumab (240 mg intravenously every 2nd week). Patients in arm A will be offered ipi + nivo after disease progression.

DISCUSSION

ICON is among the first clinical trials combining chemotherapy with PD-1 and CTLA-4 blockade, and the first in BC. There is a strong preclinical rationale for exploring if anthracyclines, which are considered to induce immunogenic cell death, synergize with CPI, and for combining PD-1 and CTLA-4 blockade, as these checkpoints are important in different phases of the immune response. If the ICON trial suggests acceptable safety and provide a signal of clinical efficacy, further studies are warranted. The cross-over patients from Arm A receiving ipilimumab/nivolumab without concomitant chemotherapy represent the first BC cohort receiving this therapy. The ICON trial includes a series of translational sub-projects addressing clinically important knowledge gaps. These studies may uncover biomarkers or mechanisms of efficacy and resistance, thereby informing the development of novel combinatory regimes and of personalised biomarker-based therapy. Trial registration NCT03409198, Jan 24th 2018; https://clinicaltrials.gov/ct2/show/record/NCT03409198.

Non-Small Cell Lung Cancer Patient Preferences for First-Line Treatment: A Discrete Choice Experiment

Background. There has been much innovation in the treatment of non-small cell lung cancer (NSCLC) in recent years. In particular, use of immuno-oncology (IO) therapies has been growing. Methods. Patients with NSCLC in the United States were surveyed online using a discrete choice experiment to elicit first-line (1L) treatment preferences across six treatment attributes: survival, adverse events (AEs), mechanism of action (MOA), subsequent treatment options (STOs), genetic testing treatment delay, and out-of-pocket cost (OOPC). Preferences were estimated using a latent-class model. Preference shares were estimated for IO-IO, IO-chemo, and chemo-like regimens. Results. Of the 199 patients who completed the survey, 55% were male, 76% were white, 19% had not begun or were on 1L treatment, and the median age was 43 years. Based on a latent-class model with 3 preference classes, 53.0% of patients considered survival and OOPC alone and were less likely to choose an option with a higher OOPC and lower survival, 12.7% of patients were likely to choose the more expensive option, and for 34.3% of patients, survival, AE risk, and treatment delays all significantly influenced choices. MOA and STOs did not significantly influence treatment choices in any preference class. Approximately 53%, 27%, and 20% of patients preferred IO-IO-like, IO-chemo-like, and chemo-like regimens in 1L, respectively. Respondents were younger, more likely to be Caucasian, and more likely to speak English than the general NSCLC patient population. Conclusions. OOPC, effectiveness, treatment delays, and safety influenced NSCLC patients' 1L treatment decisions, and most patients preferred an IO-IO followed by IO-chemo-like regimen in 1L. Cancer treatment decisions are complex and patient preferences are unique; therefore, patients' treatment objectives should be discussed in shared treatment decision making.

Immune Checkpoint Blockade: The New Frontier in Cancer Treatment

Immune checkpoint blockers have revolutionized cancer treatment in recent years. These agents are now approved for the treatment of several malignancies, including melanoma, squamous and non-squamous non-small cell lung cancer, renal cell carcinoma, urothelial carcinoma, and head and neck squamous cell carcinoma. Studies have demonstrated the significant impact of immunotherapy versus standard of care on patient outcomes, including durable response and extended survival. The use of immunotherapy-based combination therapy has been shown to further extend duration of response and survival. Immunotherapies function through modulation of the immune system, which can lead to immune-mediated adverse events (imAEs). These include a range of dermatologic, gastrointestinal, endocrine, and hepatic toxicities, as well as other less common inflammatory events. ImAEs are typically low grade and manageable when identified early and treated with appropriate measures. Identifying the right patient for the right therapy will become more important as new immunotherapies and immunotherapy-based combinations are approved and costs of cancer care continue to rise.

A Changing of the Guard: Immune Checkpoint Inhibitors With and Without Chemotherapy as First Line Treatment for Metastatic Non-small Cell Lung Cancer

Inhibitory antibodies targeting programmed death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) have resulted in improved outcomes for many patients with metastatic non-small cell lung cancer in (NSCLC) in the second-line setting due to their ability to lead to prolonged anti-tumor immune responses. Combining these immunotherapies with platinum-based chemotherapy as first-line treatment has resulted in improved response rates and increased survival when compared to platinum-based chemotherapy alone. Certain patient populations may even benefit from immune checkpoint inhibitors as monotherapy in the first-line setting. The PD-1 inhibitor pembrolizumab is approved as monotherapy or in combination with platinum + pemetrexed for most newly diagnosed patients with metastatic NSCLC, excluding those with a targetable oncogene such as ALK and EGFR. The PD-L1 inhibitor atezolizumab is also approved in combination with bevacizumab + carboplatin + paclitaxel for the same population, with some parts of the world also approving this regimen for patients with ALK rearrangements or EGFR activating mutations. However, there are many other chemo-immunotherapy regimens that have been evaluated as initial treatment in metastatic NSCLC. Additionally, combinations of PD-1 axis inhibitors with cytotoxic T lymphocyte antigen-4 inhibitors have been examined, although none are yet approved. Here we review the clinical data in support of the current first-line approaches across histologies and biomarker subtypes, as well as highlight future research directions revealed by the current data.

Immunotherapy with checkpoint inhibitors in non-small cell lung cancer: insights from long-term survivors

Immune checkpoint inhibitors (ICIs) targeting the programmed cell death-1 (PD-1)-programmed cell death ligand-1 (PD-L1) axis have shown promising results in non-small cell lung cancer (NSCLC) patients, some of them with persistent responses to these agents that form a population of long-term survivors. Despite the variable definition of PD-L1 positivity in tumors, an association between expression and response has been reasonably consistent in advanced NSCLC. In addition, the clinical efficacy of ICIs seems to be related to the genomic landscape of the tumor in terms of mutational burden and clonal neoantigens. Furthermore, increasing evidence shows that excessive activation of the immune response elicited by ICIs, leading to immune-related toxicities, might be associated with an improved response to immunotherapy. There are still many unanswered questions about the proper use of these agents to maximize their efficacy, which may be improved through combination with radiation, chemotherapy, targeted therapies, or other immune mediators, including dual checkpoint blockade. To search for clues for addressing these challenges, this review focused on the characteristics and clinical features of long-term NSCLC survivors and the potential biomarkers of response to ICIs.

First-Line Nivolumab Plus Ipilimumab in Advanced Non-Small-Cell Lung Cancer (CheckMate 568): Outcomes by Programmed Death Ligand 1 and Tumor Mutational Burden as Biomarkers

PURPOSE

CheckMate 568 is an open-label phase II trial that evaluated the efficacy and safety of nivolumab plus low-dose ipilimumab as first-line treatment of advanced/metastatic non–small-cell lung cancer (NSCLC). We assessed the association of efficacy with programmed death ligand 1 (PD-L1) expression and tumor mutational burden (TMB).

PATIENTS AND METHODS

Two hundred eighty-eight patients with previously untreated, recurrent stage IIIB/IV NSCLC received nivolumab 3 mg/kg every 2 weeks plus ipilimumab 1 mg/kg every 6 weeks. The primary end point was objective response rate (ORR) in patients with 1% or more and less than 1% tumor PD-L1 expression. Efficacy on the basis of TMB (FoundationOne CDx assay) was a secondary end point.

RESULTS

Of treated patients with tumor available for testing, 252 patients (88%) of 288 were evaluable for PD-L1 expression and 98 patients (82%) of 120 for TMB. ORR was 30% overall and 41% and 15% in patients with 1% or greater and less than 1% tumor PD-L1 expression, respectively. ORR increased with higher TMB, plateauing at 10 or more mutations/megabase (mut/Mb). Regardless of PD-L1 expression, ORRs were higher in patients with TMB of 10 or more mut/Mb (n = 48: PD-L1, ≥ 1%, 48%; PD-L1, < 1%, 47%) versus TMB of fewer than 10 mut/Mb (n = 50: PD-L1, ≥ 1%, 18%; PD-L1, < 1%, 5%), and progression-free survival was longer in patients with TMB of 10 or more mut/Mb versus TMB of fewer than 10 mut/Mb (median, 7.1 v 2.6 months). Grade 3 to 4 treatment-related adverse events occurred in 29% of patients.

CONCLUSION

Nivolumab plus low-dose ipilimumab was effective and tolerable as a first-line treatment of advanced/metastatic NSCLC. TMB of 10 or more mut/Mb was associated with improved response and prolonged progression-free survival in both tumor PD-L1 expression 1% or greater and less than 1% subgroups and was thus identified as a potentially relevant cutoff in the assessment of TMB as a biomarker for first-line nivolumab plus ipilimumab.

Retrospect and Prospect for Lung Cancer in China: Clinical Advances of Immune Checkpoint Inhibitors

Lung cancer is the most commonly diagnosed cancer and the leading cause of cancer-related deaths in China. The recent emergence of immunotherapy treatment options, such as the use of programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) checkpoint inhibitors, has also led to a paradigm shift in the treatment of non-small cell lung cancer, and has provided promising directions for the treatment of small cell lung cancer. This review provides a summary of the developmental process of immunotherapy, especially immune checkpoint inhibitors in lung cancer, ongoing international and domestic clinical trials in this field, and the challenges and considerations related to the use of immunotherapy in Chinese patients with lung cancer, with the aim of providing detailed information for future immunotherapy-related clinical trials in China. Research regarding immune checkpoint inhibitors in China is several years behind similar research in several developed countries. However, although PD-1/PD-L1 inhibitor-related clinical trials remain in their early stages in China, increased efforts by Chinese clinicians, researchers, and government staff have been directed toward trying to introduce novel drugs into the clinical setting. Because of the specific characteristics of Chinese patients with lung cancer (such as high epidermal growth factor receptor mutation rates, later disease stages, and different toxicity profiles), large-scale clinical trials targeting the Chinese population or Chinese participation in multinational trials should be promoted. IMPLICATIONS FOR PRACTICE: As the leading cause of cancer-related morbidity and mortality, lung cancer is a major public health problem in China. Immunotherapy based on programmed cell death protein 1/programmed death-ligand 1 checkpoint inhibitors may result in new treatment directions and a paradigm shift for Chinese patients with lung cancer. Although checkpoint inhibitor-related clinical trials remain in their early stages in China, increased efforts by Chinese clinicians, researchers, and government staff have been directed toward trying to introduce novel drugs into the clinical setting by encouraging the development of large-scale clinical trials targeting the Chinese population and promoting Chinese patients with lung cancer to participate in international trials.

Predictive biomarkers of response for immune checkpoint inhibitors in non-small-cell lung cancer

Immune checkpoint blockade has been a pivotal development in the management of advanced non-small-cell lung cancer (NSCLC). Although durable antitumour activity and improved survival have been observed in a subset of patients, there is a need for additional predictive biomarkers to improve patient selection and avoid toxicity in potential non-responders. This review will address the use and limitations of tumour programmed death-ligand 1 expression as a predictive biomarker and review emerging biomarker strategies specifically related to NSCLC including genetic alterations (tumour mutation burden, loss and gain activated mutations), tumour-related factors (tumour microenvironment) and factors related to the host immune system. Novel approaches in biomarker detection such as peripheral blood monitoring will also be reviewed.

Toward innovative combinational immunotherapy: A systems biology perspective

The treatment of non-small-cell lung cancer (NSCLC) has advanced significantly in the last decades. Especially immune checkpoint inhibitors have shown inconceivable effect on enhancing host anti-tumor activity in NSCLC. However, the limitation of checkpoint blockade monotherapy seems unavoidable in most of the NSCLC patients and only ∼20% of them achieved response to monotherapy with immune checkpoint inhibitors. Thus combining immune checkpoint inhibitors with other agents with different action mechanisms holds a promise to revitalize NSCLC treatment, such as the combination of checkpoint inhibitors with angiogenesis inhibitors, or with chemotherapy, as well as the combination of two checkpoint inhibitors. Recently, various combinational strategies have been explored to setup promising combination regimens and to understand the action mechanisms. In this review, we summarize the suspected synergistic mechanisms of several combinational approaches by reviewing the available preclinical and clinical data. Then we discuss in light of the current knowledge of cancer biology and systems biology the important facets to be examined when setting up a framework for developing immunotherapy-based combination strategies.