Combined Nivolumab and Ipilimumab or Monotherapy in Untreated Melanoma

A phase I trial of panobinostat (LBH589) in patients with metastatic melanoma

Epigenetic alterations by histone/protein deacetylases (HDACs) are one of the many mechanisms that cancer cells use to alter gene expression and promote growth. HDAC inhibitors have proven to be effective in the treatment of specific malignancies, particularly in combination with other anticancer agents. We conducted a phase I trial of panobinostat in patients with unresectable stage III or IV melanoma. Patients were treated with oral panobinostat at a dose of 30 mg daily on Mondays, Wednesdays, and Fridays (Arm A). Three of the six patients on this dose experienced clinically significant thrombocytopenia requiring dose interruption. Due to this, a second treatment arm was opened and the dose was changed to 30 mg oral panobinostat three times a week every other week (Arm B). Six patients were treated on Arm A and 10 patients were enrolled to Arm B with nine patients treated. In nine patients treated on Arm B, the response rate was 0% (90% confidence interval [CI]: 0–28%) and the disease‐control rate was 22% (90% CI: 4–55%). Among all 15 patients treated, the overall response rate was 0% (90% CI: 0–17%) and the disease‐control rate was 27% (90% CI: 10–51%). There was a high rate of toxicity associated with treatment. Correlative studies suggest the presence of immune modifications after HDAC inhibition. Panobinostat is not active as a single agent in the treatment of melanoma. Further exploration of this agent in combination with other therapies may be warranted.

Targeting the MAPK and PI3K pathways in combination with PD1 blockade in melanoma

Immunotherapy of advanced melanoma with CTLA-4 or PD-1/PD-L1 checkpoint blockade induces in a proportion of patients long durable responses. In contrast, targeting the MAPK-pathway by selective BRAF and MEK inhibitors induces high response rates, but most patients relapse. Combining targeted therapy with immunotherapy is proposed to improve the long-term outcomes of patients. Preclinical data endorsing this hypothesis are accumulating. Inhibition of the PI3K-Akt-mTOR pathway may be a promising treatment option to overcome resistance to MAPK inhibition and for additional combination with immunotherapy.

We therefore evaluated to which extent dual targeting of the MAPK and PI3K-Akt-mTOR pathways affects tumor immune infiltrates and whether it synergizes with PD-1 checkpoint blockade in a BRAF^V600E/PTEN^−/−-driven melanoma mouse model. Short-term dual BRAF + MEK inhibition enhanced tumor immune infiltration and improved tumor control when combined with PD-1 blockade in a CD8⁺ T cell dependent manner. Additional PI3K inhibition did not impair tumor control or immune cell infiltration and functionality. Analysis of on-treatment samples from melanoma patients treated with BRAF or BRAF + MEK inhibitors indicates that inhibitor-mediated T cell infiltration occurred in all patients early after treatment initiation but was less frequent found in on-treatment biopsies beyond day 15.

Our findings provide a rationale for clinical testing of short-term BRAF + MEK inhibition in combination with immune checkpoint blockade, currently implemented at our institutes. Additional PI3K inhibition could be an option for BRAF + MEK inhibitor resistant patients that receive targeted therapy in combination with immune checkpoint blockade.

T cell exhaustion and immune-mediated disease-the potential for therapeutic exhaustion

T cell exhaustion represents a continuous spectrum of cellular dysfunction induced during chronic viral infection, facilitating viral persistence and associating with poor clinical outcome. Modulation of T cell exhaustion can restore function in exhausted CD8 T cells, promoting viral clearance. Exhaustion has also been implicated as playing an important role in anti-tumour responses, whereby exhausted tumour-infiltrating lymphocytes fail to control tumour progression. More recently exhaustion has been linked to long-term clinical outcome in multiple autoimmune diseases but, in contrast to cancer or infection, it is associated with a favourable clinical outcome characterised by fewer relapses. An increasing understanding of key inhibitory signals promoting exhaustion has led to advances in therapy for chronic infection and cancer. An increasing understanding of this biology may facilitate novel treatment approaches for autoimmunity through the therapeutic induction of exhaustion.

Current progress in immunotherapy for pancreatic cancer

Pancreatic cancer remains one of the most lethal cancers with few treatment options. Immune-based strategies to treat pancreatic cancer, such as immune checkpoint inhibitors, therapeutic vaccines, and combination immunotherapies, are showing promise where other approaches have failed. Immune checkpoint inhibitors, including anti-CTLA4, anti-PD-1, and anti-PD-L1 antibodies, are effective as single agents in immune sensitive cancers like melanoma, but lack efficacy in immune insensitive cancers including pancreatic cancer. However, these inhibitors are showing clinical activity, even in traditionally non-immunogenic cancers, when combined with other interventions, including chemotherapy, radiation therapy, and therapeutic vaccines. Therapeutic vaccines given together with immune modulating agents are of particular interest because vaccines are the most efficient way to induce effective anti-tumor T cell responses, which is required for immunotherapies to be effective. In pancreatic cancer, early studies suggest that vaccines can induce T cells that have the potential to recognize and kill pancreatic cancer cells, but the tumor microenvironment inhibits effective T cell trafficking and function. While progress has been made in the development of immunotherapies for pancreatic cancer over the last several years, additional trials are needed to better understand the signals within the tumor microenvironment that are formidable barriers to T cell infiltration and function. Additionally, as more pancreatic specific antigens are identified, immunotherapies will continue to be refined to provide the most significant clinical benefit.

Relevance of serum biomarkers associated with melanoma during follow-up of anti-CTLA-4 immunotherapy

Metastatic melanoma is a rapidly spreading cancer whose prognosis remains poor although important therapy advances in recent years. Ipilimumab, an anti-CTLA-4 immunotherapy used in advanced melanoma, is an effective immunotherapy alone or combined with other agents but with few predictive biomarkers of response. Here, we sought to analyze the potential of S100B, MIA, soluble MICA, anti-MICA antibodies and LDH as serum biomarkers of response and survival in a cohort of 77 advanced melanoma patients subjected to ipilimumab. Lower levels of S100B, and LDH at baseline and at weeks 3 and 6 correlated to a better response and survival. After multivariate analysis LDH maintained its independence at baseline and week 6, whereas S100B might be a useful tool for anti-CTLA-4 treatment monitoring after the first two doses of ipilimumab (W6). In addition, higher sMICA serum levels at baseline were associated with less frequency of irAEs.

The Potential of Combined Immunotherapy and Antiangiogenesis for the Synergistic Treatment of Advanced NSCLC

Over the past few years, there have been considerable advances in the treatments available to patients with metastatic or locally advanced NSCLC, particularly those who have progressed during first-line treatment. Some of the treatment options available to patients are discussed here, with a focus on checkpoint inhibitor immunotherapies (nivolumab and pembrolizumab) and antiangiogenic agents (bevacizumab, ramucirumab, and nintedanib). It is hypothesized that combining immunotherapy with antiangiogenic treatment may have a synergistic effect and enhance the efficacy of both treatments. In this review, we explore the theory and potential of this novel treatment option for patients with advanced NSCLC. We discuss the growing body of evidence that proangiogenic factors can modulate the immune response (both by reducing T-cell infiltration into the tumor microenvironment and through systemic effects on immune-regulatory cell function), and we examine the preclinical evidence for combining these treatments. Potential challenges are also considered, and we review the preliminary evidence of clinical efficacy and safety with this novel combination in a variety of solid tumor types.

Contemporary experience with high-dose interleukin-2 therapy and impact on survival in patients with metastatic melanoma and metastatic renal cell carcinoma

High-dose interleukin-2 (HD IL-2) was approved for treatment of metastatic renal cell carcinoma (mRCC) in 1992 and for metastatic melanoma (mM) in 1998, in an era predating targeted therapies and immune checkpoint inhibitors. The PROCLAIM^SM registry was established to collect and analyze data for patients treated with HD IL-2 in the current era. This analysis includes 170 patients with mM and 192 patients with mRCC treated between 2005 and 2012 with survival data current as of July 27, 2015. For patients with mM, complete response (CR) was observed in 5 %, partial response (PR) in 10 %, stable disease (SD) in 22 %, and 63 % had progressive disease (PD). The median overall survival (mOS) for these patients was 19.6 months, with a median follow-up of 43.1 months. The mOS was not reached for patients achieving CR or PR, and was 33.4 months for patients with SD. For patients with mRCC, 6 % achieved CR, 9 % had PR, 22 % had SD, and 62 % had PD. The mOS was 41 months, with a median follow-up of 46.6 months. The mOS for patients who had CR and PR was not reached and was 49.6 months for patients with SD. There were no treatment-related deaths among 362 patients. The duration of mOS for patients with mM and mRCC is longer than historically reported. These data support a continued role for IL-2 in the treatment of eligible patients with mM or mRCC and warrant further evaluation of HD IL-2 in combination or sequence with other therapeutic agents.

Cessation of targeted therapy after a complete response in BRAF-mutant advanced melanoma: a case series

BACKGROUND

It is unknown whether melanoma patients achieving complete response (CR) with targeted therapy can safely discontinue treatment.

METHODS

All patients treated with BRAF/MEK inhibitors achieving CR and ceasing treatment before progression were identified. Clinical data at treatment initiation, cessation and progression were examined.

RESULTS

A total of 12 eligible patients were identified, with median follow-up of 16 months, of whom 6 (50%) recurred at a median of 6.6 months after treatment cessation. One patient lost to follow-up until presentation with symptomatic recurrence was the only relapser to die. At relapse, the remaining five patients had an LDH <1.2 times ULN, four were ECOG 0 and one ECOG 1. Baseline characteristics and time to CR and to discontinuation did not influence the rate of relapse.

CONCLUSIONS

A large proportion of patients achieving CR with BRAF/MEK inhibitors relapse after treatment cessation. The optimal treatment duration in such patients is unclear, particularly where alternative treatments are available.

Pembrolizumab for the treatment of non-small cell lung cancer

INTRODUCTION

Immune checkpoint inhibitors targeting programmed death protein 1 (PD-1) receptor and its ligand, PD-L1, have recently led to significant and durable improvements in the clinical outcomes of some types of cancers including lung cancer.

AREAS COVERED

Pembrolizumab was approved by the US FDA for the treatment of advanced or metastatic NSCLC whose disease has progressed after other treatments and with tumors that express PD-L1. In the phase I KEYNOTE-001 trial, the overall response rate (ORR) was 19.4%, the median progression-free survival (PFS) and overall survival (OS) were 3.7 months and 12.0 months for 495 unselected NSCLC patients. Strong PD-L1 expression (≥ 50%) was associated with higher ORR, longer PFS, and longer OS. The phase II/III randomized KEYNOTE-010 trial demonstrated that pembrolizumab improved OS versus docetaxel in patients with previously treated NSCLC.

EXPERT OPINION

Pembrolizumab, demonstrated durable response and prolonged OS especially in NSCLC patients with high expression of PD-1, thereby suggests a new treatment paradigm. However, many issues remain to be explored, including the identification of other robust biomarkers that can accurately predict the immune-responsiveness of tumors. Along with the identification of predictive biomarkers, further understanding of the tumor microenvironment is necessary to improve treatment outcomes through combinations of immunotherapy or combined with other targeted therapies.

Cobimetinib

OBJECTIVE

To review and summarize data on cobimetinib, which was approved by the US Food and Drug Administration (FDA) in November 2015 for use in combination with vemurafenib for unresectable or metastatic melanoma with a BRAFV600E or V600K mutation.

DATA SOURCES

A literature search using PubMed was conducted using the terms cobimetinib, MEK inhibitor, and melanoma from January 2000 to June 2016.

STUDY SELECTION AND DATA EXTRACTION

The literature search was confined to human studies published in English. Trials of cobimetinib for melanoma were prioritized.

DATA SYNTHESIS

Cobimetinib is a reversible inhibitor of MEK1 and MEK2. Its FDA approval was based on a phase III, randomized trial of vemurafenib monotherapy (n = 248) or vemurafenib and cobimetinib (n = 247) in unresectable stage IIIC or IV melanoma with a BRAFV600 mutation. Cobimetinib was administered as 60 mg orally daily for 21 days/7 days off, whereas vemurafenib was administered as 960 mg twice daily. Vemurafenib and cobimetinib were associated with an objective response rate of 68%, and median progression-free survival of 9.9 months. The overall survival was not reached at the time of first interim analysis. Clinically relevant grade ≥3 adverse events were diarrhea (6%), rash (6%), photosensitivity (2%), elevated liver function tests (LFTs) (8%-12%), increased creatine kinase (11%), and retinal detachment (3%).

CONCLUSION

Cobimetinib combined with vemurafenib is an alternative BRAF/MEK inhibitor therapy for unresectable or metastatic melanoma with BRAFV600 mutation. The role of cobimetinib in melanoma and other solid tumors is likely to expand as the results from ongoing studies become available.

Spotlight on talimogene laherparepvec for the treatment of melanoma lesions in the skin and lymph nodes

On October 27, 2015, talimogene laherparepvec (T-VEC), a first in class intralesional oncolytic virotherapy, was granted the US Food and Drug Administration approval for the treatment of melanoma in the skin and lymph nodes. Its approval has added yet another therapeutic option to the growing list of effective therapies for melanoma. Though the Phase III OPTiM trial has demonstrated its efficacy as a single agent, the target patient population remains narrow. With numerous effective and tolerable treatments available for unresectable and metastatic melanoma, intralesional therapies such as T-VEC are still finding their niche. T-VEC is now widely accepted as option for treatment; however, its combination with various other agents in an effort to expand its use and synergize with other interventions is still being explored. This article will review the pre-clinical and clinical work that eventually led to the Food and Drug Administration approval of this first-in-class agent, as well as address concerns about clinical application and ongoing research.

Clonal expansion of CD8 T cells in the systemic circulation precedes development of ipilimumab-induced toxicities

Immune checkpoint therapies, such as ipilimumab, induce dramatic antitumor responses in a subset of patients with advanced malignancies, but they may also induce inflammatory responses and toxicities termed immune-related adverse events (irAEs). These irAEs are often low grade and manageable, but severe irAEs may lead to prolonged hospitalizations or fatalities. Early intervention is necessary to minimize morbidities that occur with severe irAEs. However, correlative biomarkers are currently lacking. In a phase II clinical trial that treated 27 patients with metastatic prostate cancer, we aimed to test the safety and efficacy of androgen deprivation therapy plus ipilimumab. In this study, we observed grade 3 toxicities in >40% of treated patients, which led to early closure of the study. Because ipilimumab enhances T-cell responses, we hypothesized that increased clonal T-cell responses in the systemic circulation may contribute to irAEs. Sequencing of the T-cell receptor β-chains in purified T cells revealed clonal expansion of CD8 T cells, which occurred in blood samples collected before the onset of grade 2-3 irAEs. These initial results suggested that expansion of ≥55 CD8 T-cell clones preceded the development of severe irAEs. We further evaluated available blood samples from a second trial and determined that patients who experienced grade 2-3 irAEs also had expansion of ≥55 CD8 T-cell clones in blood samples collected before the onset of irAEs. We propose that CD8 T-cell clonal expansion may be a correlative biomarker to enable close monitoring and early intervention for patients receiving ipilimumab.

Genomic Approaches to Understanding Response and Resistance to Immunotherapy

Immunotherapy has led to a paradigm shift in the treatment of some malignancies, providing long-term, durable responses for patients with advanced cancers. However, such therapy has benefited only a subset of patients, with some patients failing to respond to treatment at all and others achieving a limited response followed by tumor progression. Understanding factors contributing to an effective response and further elucidating mechanisms of resistance will be crucial as these therapies are applied more broadly. Genomics-based approaches have significantly advanced the study of response and resistance to immunotherapy in general, and to immune checkpoint blockade more specifically. Here, we review how genomic and transcriptomic approaches have identified both somatic and germline positive correlates of response, including high mutational/neoantigen load and low intratumoral heterogeneity, among others. The genomic analysis of resistant tumors has additionally identified crucial factors involved in resistance to immune checkpoint blockade, including loss of PTEN and upregulation of other immune checkpoints. Overall, the continued use of genomic techniques at the point of care, combined with appropriate functional studies, would ideally lead to a better understanding of why certain patients respond to immune-based therapies, allowing clinicians to identify the subset of patients likely to benefit from such therapy, and potentially providing insight into how other therapies may be added in combination to increase the number of patients who may benefit from immunotherapy. Clin Cancer Res; 22(23); 5642-50. ©2016 AACR.

Advances in immunotherapy for melanoma management

Melanoma remains a leading cause of death among young adults. Evidence that melanoma tumor cells are highly immunogenic and a better understanding of T-cell immune checkpoints have changed the therapeutic approach to advanced melanoma. Instead of targeting the tumor directly, immunotherapy targets and activates the immune response using checkpoint inhibitors, monoclonal antibodies, vaccines, and adoptive T cell therapy. This review focuses on the immune signaling and biological mechanisms of action of recent immune-based melanoma therapies as well as their clinical benefits.

The full blood count as a biomarker of outcome and toxicity in ipilimumab-treated cutaneous metastatic melanoma

Ipilimumab produces durable responses in some metastatic melanoma patients. Neutrophil, platelet, and eosinophil to lymphocyte ratios (NLR, PLR, and ELR) may be associated with the immune response in cancer thereby acting as biomarkers of toxicity and efficacy in ipilimumab-treated patients. Data were collected on clinical characteristics and lactate dehydrogenase (LDH), NLR, PLR, and ELR at baseline, post cycle 2 and at the end of treatment for 183 patients treated with ipilimumab between 2008 and 2015 at the Princess Margaret Cancer Centre. Associations between clinical characteristics, LDH, NLR, PLR, and ELR with toxicity or survival outcomes of progression-free (PFS) and overall survival (OS) were assessed using univariable and multivariable analysis. Prognostic models of outcome at each time point were determined. Of the 183 patients included, the median age was 58, 85% had M1c disease, 58% were performance status 1, and 64% received ipilimumab as second line therapy. Median follow up was 7.5 months (range: 0.3-49.5), median PFS was 2.8 months (95% confidence intervals (CI): 2.8-3.2), and median OS was 9.6 months (95% CI: 7.9-13.2). Prognostic factors for OS by multivariable analysis were LDH and NLR at all-time points. Prognostic models using LDH (× 2 upper limit of normal) and NLR 4) differentiated patients into high, moderate, and low risk of death prior to or on ipilimumab treatment (P < 0.0001 for each model). No factors were associated with toxicity. Prognostic models based on NLR and LDH values at baseline and on treatment differentiate patients into good, intermediate, and poor prognostic groups and may be relevant in patient management.

Systemic therapy for bladder cancer finally comes into a new age

Systemic therapy for bladder cancer, both localized muscle-invasive disease and metastatic disease, has seen minimal progress over the past two decades. Current approaches rely upon cytotoxic chemotherapy combinations aimed at increasing cure rates or achieving palliation and disease control, but these regimens are fraught with short- and long-term toxicities and outcomes remain suboptimal. The emergence of systemic immunotherapies that can provide durable remissions in subsets of patients with other malignancies has the potential to transform the field, and early phase trials have begun to demonstrate activity in some patients with metastatic bladder cancer. In this article, we review the current state of systemic therapy for bladder cancer and discuss the current literature and ongoing trials utilizing various immunotherapies.

Mutational signatures in esophageal adenocarcinoma define etiologically distinct subgroups with therapeutic relevance

Esophageal adenocarcinoma (EAC) has a poor outcome, and targeted therapy trials have thus far been disappointing owing to a lack of robust stratification methods. Whole-genome sequencing (WGS) analysis of 129 cases demonstrated that this is a heterogeneous cancer dominated by copy number alterations with frequent large-scale rearrangements. Co-amplification of receptor tyrosine kinases (RTKs) and/or downstream mitogenic activation is almost ubiquitous; thus tailored combination RTK inhibitor (RTKi) therapy might be required, as we demonstrate in vitro. However, mutational signatures showed three distinct molecular subtypes with potential therapeutic relevance, which we verified in an independent cohort (n = 87): (i) enrichment for BRCA signature with prevalent defects in the homologous recombination pathway; (ii) dominant T>G mutational pattern associated with a high mutational load and neoantigen burden; and (iii) C>A/T mutational pattern with evidence of an aging imprint. These subtypes could be ascertained using a clinically applicable sequencing strategy (low coverage) as a basis for therapy selection.

Systemic Therapies for Late-stage Melanoma

Late-stage melanoma is associated with high morbidity and mortality. Classic treatment methods relied on cytotoxic chemotherapy, which is limited by low response rates and significant adverse effects. Recent advances in immunogenetics have led to the advent of important new systemictreatments.Thisarticle reviews the latest therapy options for advanced melanoma.

Ipilimumab and Bevacizumab in Glioblastoma

The median survival in glioblastoma is just over a year, with no standard second-line therapy. Ipilimumab is an immune checkpoint inhibitor that activates the anti-tumour immune response by cytotoxic T-lymphocyte antigen-4 blockade. There is significant evidence supporting its role in the treatment of malignant melanoma, including in patients with brain metastases. The addition of the anti-angiogenesis agent, bevacizumab, seems to offer additional benefit and limit the immune-related side-effects of ipilimumab in melanoma. To date there have been no clinical trials investigating this combination in glioblastoma. In this single practice case series, 20 patients with glioblastoma were consented for and treated with ipilimumab and bevacizumab in combination. Safety, tolerability and the response to treatment were reviewed for all patients. Three patients were treated after palliative first-line radiotherapy, one patient after first-line chemoradiation and 16 patients were treated with recurrent disease. Sixty-five per cent of patients completed four cycles of 3 weekly ipilimumab therapy, administered with 2 weekly bevacizumab. Radiographic responses for patients with recurrent disease were evaluated by Response Assessment in Neuro-oncology (RANO) criteria; 31% of patients showed a partial response, 31% had stable disease and 38% had disease progression. The treatment combination was well tolerated, with treatment terminated before completion due to adverse events in two patients. Autoimmune toxicity was manageable with systemic corticosteroid therapy. Ipilimumab and bevacizumab in combination show promising activity with a predictable and manageable toxicity profile, warranting further clinical studies.

Inflammation-Triggered Cancer Immunotherapy by Programmed Delivery of CpG and Anti-PD1 Antibody

Inflammation-triggered combination delivery of anti-PD-1 antibody and CpG oligodeoxynucleotides (CpG ODNs) has been demonstrated to prevent cancer relapse utilizing postsurgical inflammatory response. The controlled release of anti-PD1 and CpG ODN by CpG DNA-based "nano-cocoons" can induce considerable immune response, which in turn significantly prolongs the survival time of mice.

Perspectives for immunotherapy in endocrine cancer

The fight against cancer has seen major breakthroughs in recent years. More than a decade ago, tyrosine kinase inhibitors targeting constitutively activated signaling cascades within the tumor inaugurated a new era of oncological therapy. Recently, immunotherapy with immune checkpoint inhibitors has started to revolutionize the treatment of several malignancies, most notably malignant melanoma, leading to the renaissance and the long-awaited breakthrough of immunooncology. This review provides an overview of the basis of immunotherapy from its initial concepts of anti-tumor immunity and cell-based therapy to the development of immune checkpoint inhibitors and discusses published studies and the perspectives of immunooncology for the treatment of endocrine malignancies.

The current status of checkpoint inhibitors in metastatic bladder cancer

For many decades, no significant improvements could be achieved to prolong the survival in metastatic bladder cancer. Recently, systemic immunotherapy with checkpoint inhibitors (anti-PD-L1/anti-CTLA-4) has been introduced as a novel treatment modality for patients with metastatic bladder cancer. We conducted a systematic review according to the PRISMA statement for data published on the clinical efficacy of checkpoint inhibitors in metastatic bladder cancer. Clinical efficacy of anti PD-L1 therapy was investigated in prospective trials in a total of 155 patients. Patients with positive expression for PD-L1 tended towards better overall response rates (ORR) compared to those with negative expression (34/76 vs 10/73, 45 vs 14 %; p = 0.21). Among patients with PD-L1 positive tumors, those with non-visceral metastases exhibited significantly higher ORR compared to those with visceral metastases (82 vs 28 %; p = 0.001). For anti-CTLA4 therapy, there were no data retrievable on clinical efficacy. Although data on clinical efficacy of checkpoint inhibitors in metastatic bladder cancer are currently limited, the efficacy of these drugs might depend mainly on the metastatic volume and immune system integrity. Patients with PD-L1 positive tumors and non-visceral metastases seem to derive the highest benefit from therapy.

Targeting PI3K in Cancer: Impact on Tumor Cells, Their Protective Stroma, Angiogenesis, and Immunotherapy

The PI3K pathway is hyperactivated in most cancers, yet the capacity of PI3K inhibitors to induce tumor cell death is limited. The efficacy of PI3K inhibition can also derive from interference with the cancer cells' ability to respond to stromal signals, as illustrated by the approved PI3Kδ inhibitor idelalisib in B-cell malignancies. Inhibition of the leukocyte-enriched PI3Kδ or PI3Kγ may unleash antitumor T-cell responses by inhibiting regulatory T cells and immune-suppressive myeloid cells. Moreover, tumor angiogenesis may be targeted by PI3K inhibitors to enhance cancer therapy. Future work should therefore also explore the effects of PI3K inhibitors on the tumor stroma, in addition to their cancer cell-intrinsic impact.

SIGNIFICANCE

The PI3K pathway extends beyond the direct regulation of cancer cell proliferation and survival. In B-cell malignancies, targeting PI3K purges the tumor cells from their protective microenvironment. Moreover, we propose that PI3K isoform-selective inhibitors may be exploited in the context of cancer immunotherapy and by targeting angiogenesis to improve drug and immune cell delivery. Cancer Discov; 6(10); 1090-105. ©2016 AACR.

Translating nanoparticulate-personalized cancer vaccines into clinical applications: case study with RNA-lipoplexes for the treatment of melanoma

The development of nucleic acid based vaccines against cancer has gained considerable momentum through the advancement of modern sequencing technologies and on novel RNA-based synthetic drug formats, which can be readily adapted following identification of every patient's tumor-specific mutations. Furthermore, affordable and individual ‘on demand’ production of molecularly optimized vaccines should allow their application in large groups of patients. This has resulted in the therapeutic concept of an active personalized cancer vaccine, which has been brought into clinical testing. Successful trials have been performed by intranodal administration of sterile isotonic solutions of synthetic RNA vaccines. The second generation of RNA vaccines which is currently being developed encompasses intravenously injectable RNA nanoparticle formulations (lipoplexes), made up from lipid excipients, denoted RNA(LIP). A first product that has made its way from bench to bedside is a therapeutic vaccine for intravenous administration based on a fixed set of four RNA lipoplex drug products, each encoding for one shared tumor antigen (Lipoplex Melanoma RNA Immunotherapy, ‘Lipo-MERIT’). This article describes the steps for translating these novel RNA nanomedicines into clinical trials.

Targeting Immune Checkpoints in Hematologic Malignancies

The use of antibodies that target immune checkpoint molecules on the surface of T-lymphocytes and/or tumor cells has revolutionized our approach to cancer therapy. Cytotoxic-T-lymphocyte antigen (CTLA-4) and programmed cell death protein 1 (PD-1) are the two most commonly targeted immune checkpoint molecules. Although the role of antibodies that target CTLA-4 and PD-1 has been established in solid tumor malignancies and Food and Drug Administration approved for melanoma and non-small cell lung cancer, there remains a desperate need to incorporate immune checkpoint inhibition in hematologic malignancies. Unlike solid tumors, a number of considerations must be addressed to appropriately employ immune checkpoint inhibition in hematologic malignancies. For example, hematologic malignancies frequently obliterate the bone marrow and lymph nodes, which are critical immune organs that must be restored for appropriate response to immune checkpoint inhibition. On the other hand, hematologic malignancies are the quintessential immune responsive tumor type, as proven by the success of allogeneic stem cell transplantation (allo-SCT) in hematologic malignancies. Also, sharing an immune cell lineage, malignant hematologic cells often express immune checkpoint molecules that are absent in solid tumor cells, thereby offering direct targets for immune checkpoint inhibition. A number of clinical trials have demonstrated the potential for immune checkpoint inhibition in hematologic malignancies before and after allo-SCT. The ongoing clinical studies and complimentary immune correlatives are providing a growing body of knowledge regarding the role of immune checkpoint inhibition in hematologic malignancies, which will likely become part of the standard of care for hematologic malignancies.

Pneumonitis in Patients Treated With Anti-Programmed Death-1/Programmed Death Ligand 1 Therapy

Purpose Pneumonitis is an uncommon but potentially fatal toxicity of anti-programmed death-1 (PD-1)/programmed death ligand 1 (PD-L1) monoclonal antibodies (mAbs). Clinical, radiologic, and pathologic features are poorly described. Methods Patients who received anti-PD-1/PD-L1 monotherapy or in combination with anti-cytotoxic T-cell lymphocyte-4 mAb were identified at two institutions (Memorial Sloan Kettering Cancer Center: advanced solid cancers, 2009 to 2014, and Melanoma Institute of Australia: melanomas only, 2013 to 2015). Pneumonitis was diagnosed by the treating investigator; cases with confirmed malignant lung infiltration or infection were excluded. Clinical, radiologic, and pathologic features of pneumonitis were collected. Associations among pneumonitis incidence, therapy received, and underlying malignancy were examined with Fisher's exact test as were associations between pneumonitis features and outcomes. Results Of 915 patients who received anti-PD-1/PD-L1 mAbs, pneumonitis developed in 43 (5%; 95% CI, 3% to 6%; Memorial Sloan Kettering Cancer Center, 27 of 578 [5%]; Melanoma Institute of Australia, 16 of 337 [5%]). Time to onset of pneumonitis ranged from 9 days to 19.2 months. The incidence of pneumonitis was higher with combination immunotherapy versus monotherapy (19 of 199 [10%] v 24 of 716 [3%]; P < .01). Incidence was similar in patients with melanoma and non-small-cell lung cancer (overall, 26 of 532 [5%] v nine of 209 [4%]; monotherapy, 15 of 417 v five of 152 [ P = 1.0]; combination, 11 of 115 v four of 57 [ P = .78]). Seventy-two percent (31 of 43) of cases were grade 1 to 2, and 86% (37 of 43) improved/resolved with drug holding/immunosuppression. Five patients worsened clinically and died during the course of pneumonitis treatment; proximal cause of death was pneumonitis (n = 1), infection related to immunosuppression (n = 3), or progressive cancer (n = 1). Radiologic and pathologic features of pneumonitis were diverse. Conclusion Pneumonitis associated with anti-PD-1/PD-L1 mAbs is a toxicity of variable onset and clinical, radiologic, and pathologic appearances. It is more common when anti-PD-1/PD-L1 mAbs are combined with anti-cytotoxic T-cell lymphocyte-4 mAb. Most events are low grade and improve/resolve with drug holding/immunosuppression. Rarely, pneumonitis worsens despite immunosuppression, and may result in infection and/or death.

Cancer immunotherapy-induced rheumatic diseases emerge as new clinical entities

Immune checkpoint inhibitors (ICIs) are newly approved treatments for advanced malignancies that are increasing survival. The mechanism of these drugs, non-specifically activating T cells, also leads to immune-mediated damage of tissue or immune-related adverse events (IRAE). IRAEs with rheumatic phenotypes are increasingly being recognised. Inflammatory arthritis, sicca syndrome, inflammatory myopathy, vasculitis and lupus nephritis have been described as a result of ICIs. Use of ICIs will be expanding in the coming years for several reasons. ICIs will be used in earlier stage cancer, for more indications, and additional drugs will be approved. The rheumatologist plays a critical role in evaluating and treating these patients. The expertise of rheumatologists in evaluating rheumatic signs and symptoms and treating patients with immunosuppression are critical in ensuring the optimal outcomes for patients with rheumatic IRAE. Collaboration between oncology and rheumatology for clinical care and research will enhance understanding of these new disease entities.

Incidence and risk of hepatic toxicities with PD-1 inhibitors in cancer patients: a meta-analysis

PURPOSE

Anti-programmed cell death receptor-1 (PD-1) antibodies have demonstrated antitumor activity in many cancer entities. Hepatic adverse events (AEs) are one of its major side effects, but the overall risks have not been systematically evaluated. Thus, we conducted this meta-analysis to investigate the overall incidence and risk of developing hepatic AEs in cancer patients treated with PD-1 inhibitors.

METHODS

PubMed, Embase, and oncology conference proceedings were searched for relevant studies. Eligible studies were randomized controlled trials of cancer patients treated with PD-1 inhibitors with adequate data on hepatic AEs.

RESULTS

A total of nine randomized controlled trials with a variety of solid tumors were eligible for the meta-analysis. The use of PD-1 inhibitors significantly increased the risk of developing all-grade hepatic AEs but not for high-grade hepatic AEs in comparison with chemotherapy or everolimus control. Additionally, the risk of all-grade and high-grade hepatic AEs with a nivolumab/ipilimumab combination was substantially higher than ipilimumab. No significant differences in the risk of all-grade and high-grade hepatic AEs were found between PD-1 inhibitors monotherapy and ipilimumab.

CONCLUSION

While the use of PD-1 inhibitors is associated with an increased risk of developing hepatic AEs in cancer patients, this is primarily for lower grade events.

Immunotherapy of melanoma: efficacy and mode of action

Forty years of research have brought about the development of antibodies that induce effective antitumor immune responses through sustained activation of the immune system. These "immune checkpoint inhibitors" are directed against immune inhibitory molecules, such as cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed death 1 (PD-1) or programmed death ligand 1 (PD-L1). Disruption of the PD-1/PD-L1 interaction improves the intermediate-term prognosis even in patients with advanced stage IV melanoma. One and a half years after treatment initiation, 30-60 % of these patients are still alive. While cancer immunotherapies usually do not eradicate metastases completely, they do cause a regression by 20-80 %. It is well established that the immune system is able to kill tumor cells, and this has also been demonstrated for immunotherapies. Preclinical data, however, has shown that anti-cancer immunity is not limited to killing cancer cells. Thus, through interferon gamma and tumor necrosis factor, the immune system is able to induce stable tumor growth arrest, referred to as senescence. Ensuring patient survival by long-term stabilization of metastatic growth will therefore become a central goal of antitumor immunotherapies. This therapeutic approach is effective in melanoma and non-small-cell lung cancer. Once immunotherapies also have an indication for common cancer types, drug prices will have to drop considerably in order to be able to keep them available to those dependent on such therapies.

Translating Science into Survival: Report on the Inaugural International Cancer Immunotherapy Conference

The inaugural International Cancer Immunotherapy Conference, cohosted by the Cancer Research Institute (CRI), the American Association for Cancer Research (AACR), the Association for Cancer Immunotherapy (CIMT), and the European Academy of Tumor Immunology (EATI), was held in New York City on September 16–19, 2015. The conference brought together nearly 1,400 scientists, clinicians, regulators, patient advocates, and other stakeholders to discuss the latest scientific developments in cancer immunology and immunotherapy, as well as the regulatory hurdles facing new drug development. This conference report summarizes the main themes that emerged during the 4-day meeting.

Synergistic Transcutaneous Immunotherapy Enhances Antitumor Immune Responses through Delivery of Checkpoint Inhibitors

Despite the promising efficacy of immunoregulation in cancer therapy, the clinical benefit has been restricted by inefficient infiltration of lymphocytes in the evolution of immune evasion. Also, immune-related adverse events have often occurred due to the off-target binding of therapeutics to normal tissues after systematic treatment. In light of this, we have developed a synergistic immunotherapy strategy that locally targets the immunoinhibitory receptor programmed cell death protein 1 (PD1) and immunosuppressive enzyme indoleamine 2,3-dioxygenase (IDO) for the treatment of melanoma through a microneedle-based transcutaneous delivery approach. The embedded immunotherapeutic nanocapsule loaded with anti-PD1 antibody (aPD1) is assembled from hyaluronic acid modified with 1-methyl-dl-tryptophan (1-MT), an inhibitor of IDO. This formulation method based on the combination strategy of "drug A in carriers formed by incorporation of drug B" facilitates the loading capacity of therapeutics. Moreover, the resulting delivery device elicits the sustained release and enhances retention of checkpoint inhibitors in the tumor microenvironment. Using a B16F10 mouse melanoma model, we demonstrate that this synergistic treatment has achieved potent antitumor efficacy, which is accompanied by enhanced effective T cell immunity as well as reduced immunosuppression in the local site.

Statistical Challenges in the Design of Late-Stage Cancer Immunotherapy Studies

The past several years have witnessed a revival of interest in cancer immunology and immunotherapy owing to striking immunologic and clinical responses to immune-directed anticancer therapies and leading to the selection of "Cancer Immunotherapy" as the 2013 Breakthrough of the Year by Science. But statistical challenges exist at all phases of clinical development. In phase III trials of immunotherapies, survival curves have been shown to demonstrate delayed clinical effects, as well as long-term survival. These unique survival kinetics could lead to loss of statistical power and prolongation of study duration. Statistical assumptions that form the foundations for conventional statistical inference in the design and analysis of phase III trials, such as exponential survival and proportional hazards, require careful considerations. In this article, we describe how the unique characteristics of patient response to cancer immunotherapies will impact our strategies on statistical design and analysis in late-stage drug development.

Targeted Next Generation Sequencing Identifies Markers of Response to PD-1 Blockade

Therapeutic antibodies blocking programmed death-1 and its ligand (PD-1/PD-L1) induce durable responses in a substantial fraction of melanoma patients. We sought to determine whether the number and/or type of mutations identified using a next-generation sequencing (NGS) panel available in the clinic was correlated with response to anti-PD-1 in melanoma. Using archival melanoma samples from anti-PD-1/PD-L1-treated patients, we performed hybrid capture-based NGS on 236-315 genes and T-cell receptor (TCR) sequencing on initial and validation cohorts from two centers. Patients who responded to anti-PD-1/PD-L1 had higher mutational loads in an initial cohort (median, 45.6 vs. 3.9 mutations/MB; P = 0.003) and a validation cohort (37.1 vs. 12.8 mutations/MB; P = 0.002) compared with nonresponders. Response rate, progression-free survival, and overall survival were superior in the high, compared with intermediate and low, mutation load groups. Melanomas with NF1 mutations harbored high mutational loads (median, 62.7 mutations/MB) and high response rates (74%), whereas BRAF/NRAS/NF1 wild-type melanomas had a lower mutational load. In these archival samples, TCR clonality did not predict response. Mutation numbers in the 315 genes in the NGS platform strongly correlated with those detected by whole-exome sequencing in The Cancer Genome Atlas samples, but was not associated with survival. In conclusion, mutational load, as determined by an NGS platform available in the clinic, effectively stratified patients by likelihood of response. This approach may provide a clinically feasible predictor of response to anti-PD-1/PD-L1. Cancer Immunol Res; 4(11); 959-67. ©2016 AACR.

Immunotherapy in breast cancer: An overview of modern checkpoint blockade strategies and vaccines

Immune therapy has recently emerged as a standard-of-care strategy for the treatment of melanoma, lung cancer, bladder cancer, among other malignancies. However, the role of immune therapy in the treatment of breast cancer is still being determined. Two current strategies for harnessing the immune system to treat cancer include drugs that modulate key T cell inhibitory checkpoints and vaccines. Specifically, modern immune therapy strategies can facilitate T-cell mediated tumor regression by priming the immune system against specific tumor associated antigens, by modulating immunoregulatory signals, or both. In breast cancer, preliminary data from preclinical and early clinical studies are promising. In fact, clinical data with checkpoint blockade as monotherapy has been reported in multiple breast cancer subtypes to date, with durable responses observed in a significant proportion of women with chemotherapy resistant disease. However, because the number of genetic mutations and thus, the number of neoantigens available for immune response are modest in most breast cancers when compared with other cancers, most breast cancers may not be inherently sensitive to immune modulation and therefore may require strategies that enhance tumor associated antigen presentation if immune modulation strategies are to be effective. To that end, studies that combine checkpoint blockade with other strategies including established systemic therapies (including hormone therapy and chemotherapy), radiation therapy, and localized therapy including tumor freezing (cryoablation) are underway in breast cancer. Studies that combine checkpoint blockade with vaccines are also planned. Herein, we provide a brief summary of key components of the immune response against cancer, a rationale for the use of immune therapy in breast cancer, data from early clinical trials of checkpoint blockade and vaccine strategies in breast cancer, and future directions in the field.

Local delivery of checkpoints antibodies

Immune checkpoint inhibitors (ICI) based cancer immunotherapy has recently attracted considerable interest in the field of cancer therapy. The relevant immunotherapeutic agents do not directly attack the tumor, but boost the body's immune system to recognize and kill cancer cells. In this commentary, recent efforts utilizing immunoengineering for local delivery of these immune checkpoint antibodies are introduced. Future opportunities and challenges in this research theme are also commented.

Improved Efficacy of Neoadjuvant Compared to Adjuvant Immunotherapy to Eradicate Metastatic Disease

Immunotherapy has recently entered a renaissance phase with the approval of multiple agents for the treatment of cancer. Immunotherapy stands ready to join traditional modalities, including surgery, chemotherapy, radiation, and hormone therapy, as a pillar of cancer treatment. Although immunotherapy has begun to have success in advanced cancer treatment, its scheduling and efficacy with surgery to treat earlier stages of cancer and prevent distant metastases have not been systematically examined. Here, we have used two models of spontaneously metastatic breast cancers in mice to illustrate the significantly greater therapeutic power of neoadjuvant, compared with adjuvant, immunotherapies in the context of primary tumor resection. Elevated and sustained peripheral tumor-specific immune responses underpinned the outcome, and blood sampling of tumor-specific CD8⁺ T cells immediately prior to and post surgery may provide a predictor of outcome. These data now provide a strong rationale to extensively test and compare neoadjuvant immunotherapy in humans.

SIGNIFICANCE

We demonstrate the significantly greater therapeutic efficacy of neoadjuvant, compared with adjuvant, immunotherapies to eradicate distant metastases following primary tumor resection. Elevated and sustained peripheral tumor-specific immune responses underpinned the outcome, and blood sampling of tumor-specific CD8⁺ T cells immediately prior to and post surgery may provide a predictor of outcome. Cancer Discov; 6(12); 1382-99. ©2016 AACR.See related commentary by Melero et al., p. 1312This article is highlighted in the In This Issue feature, p. 1293.

PD-1 blockade in Hodgkin's lymphoma: learning new tricks from an old teacher

INTRODUCTION

Classical Hodgkin's Lymphoma (cHL) is characterized by genetic reliance on the PD-1 pathway. Rapid accumulation of data describing the role and efficacy of PD-1 and its blockade warrants a focused review.

AREAS COVERED

In this article, we will review the unique biologic features that predispose cHL to PD-1 inhibition, current data regarding the safety and efficacy of PD-1 inhibitors in the treatment of cHL, biomarkers of immune response, ongoing clinical trials with PD-1 inhibitors, as well as areas of uncertainty. Expert commentary: The biologic and genetic underpinnings of cHL make it unique among all malignancies in its exquisite sensitivity to PD-1 inhibition. High response rates to single agent PD-1 inhibitors in early phase clinical trials serve as further proof of concept. These data strongly support continued clinical investigation of the evolving role of PD-1 inhibition in classical Hodgkin's lymphoma, including the optimal sequence, setting, and combination to best exploit the immunologic properties of this disease.

Immunotherapy for Gastroesophageal Cancer

Survival for patients with advanced oesophageal and stomach cancer is poor; together these cancers are responsible for more than a million deaths per year globally. As chemotherapy and targeted therapies such as trastuzumab and ramucirumab result in modest improvements in survival but not long-term cure for such patients, development of alternative treatment approaches is warranted. Novel immunotherapy drugs such as checkpoint inhibitors have been paradigm changing in melanoma, non-small cell lung cancer and urothelial cancers. In this review, we assess the early evidence for efficacy of immunotherapy in patients with gastroesophageal cancer in addition to considering biomarkers associated with response to these treatments. Early results of Anti- Programmed Cell Death Protein-1 (anti-PD-1), anti-PD-L1 and anti-Cytotoxic T-lymphocyte assosciated protein-4 (anti-CTLA4) trials are examined, and we conclude with a discussion on the future direction for immunotherapy for gastroesophageal cancer patients.

The cost and value of cancer drugs - are new innovations outpacing our ability to pay?

Cancer drug expenditures have been increasing significantly in countries around the world. A recent paper in the IJHPR provides new knowledge and insights into this global phenomenon by analyzing how it is playing out in an Israeli health plan with over two million members, whose state-of-the-art information systems provide an opportunity to explore these changes in a comprehensive, detailed and reliable manner. There is a wide variation in both the cost-effectiveness and the budget impact of individual drugs. These issues also vary when analyzing drugs in other countries due to differential pricing mechanisms. In addition to drug expenditure, the overall cost of cancer care is increasing, partly due to expenditures on non-pharmacologic treatments and diagnostic testing. With the arrival of new therapies, the future of cancer care is exciting. However, there will be many challenges ahead with regard to the ability to pay for such innovations. In this commentary we discuss the current problems and anticipate the future challenges.

A retrospective analysis of High-Dose Interleukin-2 (HD IL-2) following Ipilimumab in metastatic melanoma

Background

High dose interleukin-2 (HD IL-2) can induce durable responses in a subset of patients leading to long-term survival. Immune checkpoint blockade (ICB) has demonstrated similarly durable responses in a larger proportion of patients. However, not all patients respond to immune checkpoint blockade and subsequent therapeutic options need to be explored.

Methods

The PROCLAIM database was queried for patients with metastatic melanoma who had received HD IL-2 after treatment with ipilimumab or without prior ICB. Patient characteristics, toxicity and efficacy were analyzed.

Results

A total of 52 metastatic melanoma patients were treated with high dose IL-2 after ipilimumab and 276 patients were treated with high dose IL-2 without prior ICB. The overall response rate in the prior ipilimumab group was 21 % as compared to 12 % in the group that had not received prior ipilimumab. The median overall survival, measured from the initiation of HD IL-2 therapy, was 19.3 months in the prior ipilimumab group and 19.4 months in the no prior ICB group. Toxicities observed on HD IL-2 were relatively equivalent between the groups although there were cases of CTLA4 antibody-induced colitis reported after HD IL-2 treatment and a CTLA4 antibody-induced colitis related death.

Conclusion

In this retrospective analysis HD IL-2 therapy displayed antitumor activity in melanoma patients who progressed following treatment with ipilimumab. Most HD IL-2 toxicity was not worsened by prior ipilimumab therapy except for one treatment related death from colitis. Care should be taken to avoid reactivation of CTLA4 antibody-induced colitis.

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-016-0155-8) contains supplementary material, which is available to authorized users.