New challenges in endpoints for drug development in advanced melanoma

Integrating computational methods and i n vitro experimental validation reveals the pharmacological mechanism of Selaginella bryopteris (L.) Baker targeting major proteins in breast cancer

Breast cancer remains a significant global health challenge, necessitating the exploration of novel therapeutic options. The present study employs an integrated approach encompassing network pharmacology, molecular docking, molecular dynamics simulations, and in-vitro validation to investigate the potential of Selaginella bryopteris in breast cancer treatment. Initial network pharmacology analysis revealed different potential targets and pathways associated with breast cancer that could be modulated by S. bryopteris phytochemical constituents. Molecular docking and dynamics simulations further elucidated the stability and dynamics of protein-ligand complexes (lanaroflavone-EGFR and sequoiaflavone-CTNNB1). The in-vitro assays demonstrated the ability of S. bryopteris crude extract to inhibit cancer cell growth (IC50 - 78.34 μg/mL) migration and invasion, supporting the computational predictions. The integrated approach employed in the present study offers a robust framework for the systematic exploration of S. bryopteris in drug discovery as a promising candidate for breast cancer treatment.

The Treatment of Metastatic Renal Cell Carcinoma

BACKGROUND

Approximately 15 000 people receive a diagnosis of renal cell carcinoma (RCC) in Germany each year; in 20-30% of cases, metastatic RCC (mRCC) is already present at the time of diagnosis. This disease in the metastatic stage is still mainly treated palliatively, yet the multimodal therapeutic landscape has changed markedly over the past 15 years, with the approval of many new treatments for patients with mRCC.

METHODS

This review is based on prospective studies retrieved by a selective search in PubMed and the ASCO and ESMO databases and on the German and European oncological and urological guidelines for RCC.

RESULTS

Drugs are the mainstay of treatment. mRCC can be treated with a combination of two immune checkpoint inhibitors (CPIs), a CPI and a tyrosine-kinase inhibitor (TKI) (evidence level IA), or a TKI as monotherapy (evidence level IIC-IC). With prognosis-based sequential drug treatment, a mean progressionfree survival of 12 to 24 months and an overall survival of approximately 50 months can be achieved from the time of initiation of first-line therapy. Aside from pharmacotherapy, the multidisciplinary tumor board should evaluate the indications for local treatments such as cytoreductive nephrectomy, metastasectomy, and radiotherapy, depending on the individual prognostic constellation and the patient's present condition.

CONCLUSION

Optimal individualized decisions require a high level of expertise and the collabo - ration of a multidisciplinary tumor board. Older prognostic parameters currently play a leading role in decision-making, while predictive parameters and molecular markers are not yet adequately validated.

ALK5/VEGFR2 dual inhibitor TU2218 alone or in combination with immune checkpoint inhibitors enhances immune-mediated antitumor effects

Transforming growth factor β (TGFβ) is present in blood of patients who do not respond to anti-programmed cell death (ligand) 1 [PD-(L)1] treatment, and through synergy with vascular endothelial growth factor (VEGF), it helps to create an environment that promotes tumor immune evasion and immune tolerance. Therefore, simultaneous inhibition of TGFβ/VEGF is more effective than targeting TGFβ alone. In this study, the dual inhibitory mechanism of TU2218 was identified through in vitro analysis mimicking the tumor microenvironment, and its antitumor effects were analyzed using mouse syngeneic tumor models. TU2218 directly restored the activity of damaged cytotoxic T lymphocytes (CTLs) and natural killer cells inhibited by TGFβ and suppressed the activity and viability of regulatory T cells. The inactivation of endothelial cells induced by VEGF stimulation was completely ameliorated by TU2218, an effect not observed with vactosertib, which inhibits only TGFβ signaling. The combination of TU2218 and anti-PD1 therapy had a significantly greater antitumor effect than either drug alone in the poorly immunogenic B16F10 syngeneic tumor model. The mechanism of tumor reduction was confirmed by flow cytometry, which showed upregulated VCAM-1 expression in vascular cells and increased influx of CD8 + CTLs into the tumor. As another strategy, combination of anti-CTLA4 therapy and TU2218 resulted in high complete regression (CR) rates in CT26 and WEHI-164 tumor models. In particular, immunological memory generated by the combination of anti-CTLA4 and TU2218 in the CT26 model prevented the development of tumors after additional tumor cell transplantation, suggesting that the TU2218-based combination has therapeutic potential in immunotherapy.

Evaluation of Prognostic Factors for Unresectable or Recurrent Gastric Cancer Treated with Nivolumab

PURPOSE

Nivolumab is useful for the treatment of unresectable/recurrent gastric cancer as third-line or later chemotherapy. However, the factors that predict the efficacy of nivolumab monotherapy remain unclear.

METHODS

We retrospectively studied the predictive factors of response in 59 consecutive patients treated with nivolumab as third-line or later chemotherapy for unresectable/recurrent gastric cancer at our hospital from October 2017 to May 2020.

RESULTS

The median follow-up was 5.9 months. The study included 45 men and 14 women (median age: 71 years). We observed that 7 patients had an Eastern Cooperative Oncology Group performance status of 0 and 52 patients had a performance status of 1-2. Forty-three patients were treated with third-line therapy, seven with fourth-line therapy, and three with fifth-line therapy. The response rate to nivolumab was 6.7% and disease control rate was 35.5%. There were 19 (32.2%) immune-related adverse events for all grades and 9 (15.2%) for grades 3 and 4. Progression-free survival was 1.90 months, and overall survival was 6.30 months. Patients with immune-related adverse events had significantly longer overall survival than those without immune-related adverse events. Multivariate analysis showed that the occurrence of immune-related adverse events and a ratio for neutrophil-to-lymphocyte ratio after 8 weeks of nivolumab treatment to the baseline neutrophil-to-lymphocyte ratio before treatment of ≤ 1.5 were independent prognostic factors for overall survival.

CONCLUSIONS

Occurrence of immune-related adverse events and changes in neutrophil-to-lymphocyte ratio during nivolumab treatment may help predict the therapeutic efficacy of nivolumab monotherapy for unresectable or recurrent gastric cancer.

Tumor response assessment on imaging following immunotherapy

In recent years, various systemic immunotherapies have been developed for cancer treatment, such as monoclonal antibodies (mABs) directed against immune checkpoints (immune checkpoint inhibitors, ICIs), oncolytic viruses, cytokines, cancer vaccines, and adoptive cell transfer. While being estimated to be eligible in 38.5% of patients with metastatic solid or hematological tumors, ICIs, in particular, demonstrate durable disease control across many oncologic diseases (e.g., in melanoma, lung, bladder, renal, head, and neck cancers) and overall survival benefits. Due to their unique mechanisms of action based on T-cell activation, response to immunotherapies is characterized by different patterns, such as progression prior to treatment response (pseudoprogression), hyperprogression, and dissociated responses following treatment. Because these features are not encountered in the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1), which is the standard for response assessment in oncology, new criteria were defined for immunotherapies. The most important changes in these new morphologic criteria are, firstly, the requirement for confirmatory imaging examinations in case of progression, and secondly, the appearance of new lesions is not necessarily considered a progressive disease. Until today, five morphologic (immune-related response criteria (irRC), immune-related RECIST (irRECIST), immune RECIST (iRECIST), immune-modified RECIST (imRECIST), and intra-tumoral RECIST (itRECIST)) criteria have been developed to accurately assess changes in target lesion sizes, taking into account the specific response patterns after immunotherapy. In addition to morphologic response criteria, 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG-PET/CT) is a promising option for metabolic response assessment and four metabolic criteria are used (PET/CT Criteria for Early Prediction of Response to Immune Checkpoint Inhibitor Therapy (PECRIT), PET Response Evaluation Criteria for Immunotherapy (PERCIMT), immunotherapy-modified PET Response Criteria in Solid Tumors (imPERCIST5), and immune PERCIST (iPERCIST)). Besides, there is evidence that parameters on 18F-FDG-PET/CT, such as the standardized uptake value (SUV)max and several radiotracers, e.g., directed against PD-L1, may be potential imaging biomarkers of response. Moreover, the emerge of human intratumoral immunotherapy (HIT-IT), characterized by the direct injection of immunostimulatory agents into a tumor lesion, has given new importance to imaging assessment. This article reviews the specific imaging patterns of tumor response and progression and available imaging response criteria following immunotherapy.

Radiotherapy combined with immunotherapy: the dawn of cancer treatment

Radiotherapy (RT) is delivered for purposes of local control, but can also exert systemic effect on remote and non-irradiated tumor deposits, which is called abscopal effect. The view of RT as a simple local treatment has dramatically changed in recent years, and it is now widely accepted that RT can provoke a systemic immune response which gives a strong rationale for the combination of RT and immunotherapy (iRT). Nevertheless, several points remain to be addressed such as the interaction of RT and immune system, the identification of the best schedules for combination with immunotherapy (IO), the expansion of abscopal effect and the mechanism to amplify iRT. To answer these crucial questions, we roundly summarize underlying rationale showing the whole immune landscape in RT and clinical trials to attempt to identify the best schedules of iRT. In consideration of the rarity of abscopal effect, we propose that the occurrence of abscopal effect induced by radiation can be promoted to 100% in view of molecular and genetic level. Furthermore, the “radscopal effect” which refers to using low-dose radiation to reprogram the tumor microenvironment may amplify the occurrence of abscopal effect and overcome the resistance of iRT. Taken together, RT could be regarded as a trigger of systemic antitumor immune response, and with the help of IO can be used as a radical and systemic treatment and be added into current standard regimen of patients with metastatic cancer.

Clinically-meaningful improvements in therapy for unresectable NSCLC

INTRODUCTION

The ideal management of patients with unresectable non-small-cell lung cancer (NSCLC) is still developing. Unresectable NSCLC has a high mortality rate and poor prognosis, but the development of immune checkpoint inhibitors (ICIs) and molecular-targeted therapies has been a breakthrough in the treatment. The correct treatment of this patient population is crucial to maximize the clinical benefits without compromising their quality of life (QOL).

AREAS COVERED

We review the chemoradiotherapies, cytotoxic chemotherapies, immunotherapies, and molecular-targeted therapies available for unresectable NSCLC, focusing on their effects on overall survival, progression-free survival, and QOL.

EXPERT OPINION

Although cure is the ultimate goal of cancer treatment, it is often difficult to achieve in advanced NSCLC. Biomarker surveillance techniques, such as next-generation sequencing, have made it possible to provide the most appropriate treatment for each patient. This has led to clinically-meaningful improvements in therapies for unresectable NSCLC. The development of new molecular-targeted therapies and the establishment of treatment for patients who acquired drug resistance after initial treatment have a positive impact on patients' long-term survival. ICIs lead the long-term survival that can be considered a cure of some patients with advanced NSCLC, but such curative survival is difficult to achieve with cytotoxic chemotherapies and molecular-targeted therapies.

Validating Restricted Mean Survival Time Estimates From Reconstructed Kaplan-Meier Data Against Original Trial Individual Patient Data From Trials Conducted by the Canadian Cancer Trials Group

OBJECTIVES

The development of novel cancer therapies, including immuno-oncology agents, has increased interest in reconstructed individual patient data (IPD) based restricted mean survival time (RMST) analyses. Additionally, reconstructed IPD-based RMST is recommended in cost-effectiveness analyses when original trial IPD are not available. Nevertheless, recently concerns regarding potential bias of reconstructed-IPD RMST have been presented, because reconstructed-IPD RMSTs have not been validated and previous validation endpoints may not capture the entire Kaplan-Meier (KM) curve, especially the "tail." Our study aims to validate the recommended method of IPD reconstruction by comparing reconstructed IPD- and original trial IPD-based RMST.

METHODS

Canadian Cancer Trials Group trials from 1990 to 2017 were included. Overall survival and progression-free survival IPD were reconstructed based on published KM curves using the Guyot method. Analysts were blinded to original trial IPD. RMST was calculated at 1 year and over the entire KM curve. Reconstructed-IPD and original trial-IPD (gold-standard) RMSTs were compared for accuracy and predictive error via mean deviation, mean absolute error (MAE), mean percentage bias, and Bland-Altman plots and across KM curve quality (vector traced or bitmapped).

RESULTS

We identified 39 trials. The mean deviation, MAE, and mean percentage bias of RMST between the reconstructed IPD and original trial IPD were small. In particular, the mean deviation was -0.01 months and -0.04 months, MAE was 0.19 months and 0.24 months, and mean percentage bias was 0.82% and 0.84% in overall survival KM curves in control and experimental arms, respectively. Accuracy was generally not associated with KM curve quality.

CONCLUSIONS

RMST derived from reconstructed IPD displayed excellent accuracy and predictive error compared with the gold standard. Reconstructed IPD could be used to calculate RMST in lieu of original trial IPD, to facilitate decision making for clinicians, researchers, and policy makers.

Perspectives for Combining Viral Oncolysis With Additional Immunotherapies for the Treatment of Melanoma

Melanoma is the deadliest type of skin cancer with steadily increasing incidence worldwide during the last few decades. In addition to its tumor associated antigens (TAAs), melanoma has a high mutation rate compared to other tumors, which promotes the appearance of tumor specific antigens (TSAs) as well as increased lymphocytic infiltration, inviting the use of therapeutic tools that evoke new or restore pre-existing immune responses. Innovative therapeutic proposals, such as immune checkpoint inhibitors (ICIs), have emerged as effective options for melanoma. However, a significant portion of these patients relapse and become refractory to treatment. Likewise, strategies using viral vectors, replicative or not, have garnered confidence and approval by different regulatory agencies around the world. It is possible that further success of immune therapies against melanoma will come from synergistic combinations of different approaches. In this review we outline molecular features inherent to melanoma and how this supports the use of viral oncolysis and immunotherapies when used as monotherapies or in combination.

Intracellular Self-Assembly of Peptides to Induce Apoptosis against Drug-Resistant Melanoma

Biosynthesis has been a diverse toolbox to develop bioactive molecules and materials, especially for fabricating modified peptides and their assemblies induced by enzymes. Although desired chemical structures and nanoarchitectures have been achieved, the subsequent interferences of peptide assemblies with organelles and the cellular pathways still remain unsolved important challenges. Herein, we developed a new tripeptide, phenylalanine-phenylalanine-tyrosine (Phe-Phe-Tyr, or FFY), which can be intracellularly oxidized and in situ self-assemble into nanoparticles with excellent interference capability with microtubules and ultimately reverse the drug resistance of melanoma. With the catalysis of tyrosinase, FFY was first oxidized to a melanin-like FFY dimer (mFFY) with a diquinone structure for further self-assembling into mFFY assemblies, which could inhibit the self-polymerization of tubulin to induce severe G2/M arrest (13.9% higher than control). Afterward, mitochondrial dysfunction was also induced for overproduction of cleaved caspase 3 (3.1 times higher than control) and cleaved PARP (6.3 times higher), achieving a high level of resistant reversing without chemotherapeutic drugs. In vivo studies showed that the resistant melanoma tumor volumes were reduced by 87.4% compared to control groups after FFY treatment by peritumoral injections. Overall, this tyrosinase-induced tripeptide assembly has been demonstrated with effective intrinsic apoptosis against drug-resistant melanoma, providing a new insight into utilizing biomolecules to interfere with organelles to activate certain apoptosis pathways for treatment of drug-resistant cancer.

Therapeutic Advancements Across Clinical Stages in Melanoma, With a Focus on Targeted Immunotherapy

Melanoma is the most fatal skin cancer. In the early stages, it can be safely treated with surgery alone. However, since 2011, there has been an important revolution in the treatment of melanoma with new effective treatments. Targeted therapy and immunotherapy with checkpoint inhibitors have changed the history of this disease. To date, more than half of advanced melanoma patients are alive at 5 years; despite this breakthrough, approximately half of the patients still do not respond to treatment. For these reasons, new therapeutic strategies are required to expand the number of patients who can benefit from immunotherapy or combination with targeted therapy. Current research aims at preventing primary and acquired resistance, which are both responsible for treatment failure in about 50% of patients. This could increase the effectiveness of available drugs and allow for the evaluation of new combinations and new targets. The main pathways and molecules under study are the IDO inhibitor, TLR9 agonist, STING, LAG-3, TIM-3, HDAC inhibitors, pegylated IL-2 (NKTR-214), GITR, and adenosine pathway inhibitors, among others (there are currently about 3000 trials that are evaluating immunotherapeutic combinations in different tumors). Other promising strategies are cancer vaccines and oncolytic viruses. Another approach is to isolate and remove immune cells (DCs, T cells, and NK cells) from the patient's blood or tumor infiltrates, add specific gene fragments, expand them in culture with growth factors, and re-inoculate into the same patient. TILs, TCR gene transfer, and CAR-T therapy follow this approach. In this article, we give an overview over the current status of melanoma therapies, the clinical rationale for choosing treatments, and the new immunotherapy approaches.

Pembrolizumab plus axitinib for the treatment of advanced renal cell carcinoma

Introduction: The dominant paradigm of sequential therapy of metastatic renal cell carcinoma (mRCC) with single agents has recently been challenged by improved outcomes obtained with combined regimens with immune checkpoint inhibitors. These combined regimens include the combination of pembrolizumab plus axitinib.Areas covered: Here, we provide a brief overview of the current clinical data on the pembrolizumab plus axitinib combination including mechanism of action, pharmacokinetics, efficacy and safety profile.Expert opinion: Both agents targeting the vascular endothelial growth factor (VEGF) pathway and immune checkpoint inhibitors are active as single agents in mRCC. Improved outcomes have been demonstrated in phase 3 trials in comparison with sunitinib for the combinations of axitinib plus pembrolizumab, axitinib plus avelumab, bevacizumab plus atezolizumab, and ipilimumab plus nivolumab. Among these combinations, an OS benefit has, so far, demonstrated only for the combinations of axitinib with pembrolizumab and ipilimumab with nivolumab. Although there are currently no prospective data comparing the combination of ipilimumab and nivolumab with the combination of immune checkpoint inhibitors and VEGF inhibitors, currently available retrospective analyses indicate that these two approaches achieve comparable outcomes.

Rationale for Immune Checkpoint Inhibitors Plus Targeted Therapy in Metastatic Melanoma: A Review

Importance

In recent years, the management of metastatic melanoma has been transformed by the emergence of immune checkpoint inhibitors and targeted therapies that significantly improve patient survival. The complementary response kinetics of these treatment approaches, supported by mechanistic evidence that targeted therapy affects immune aspects of the tumor microenvironment, suggest that the optimal combination or sequencing of immune checkpoint inhibitors and targeted therapy may provide additional clinical benefit.

Observations

Clinical responses to BRAF and/or MEK inhibitors are associated with immune changes within the tumor microenvironment that have the potential to increase the sensitivity of BRAF V600-mutant melanoma to immune checkpoint inhibitors. The combination of immune checkpoint inhibitors with targeted therapy may therefore increase duration of response, improve tumor control, extend survival, and increase the proportion of patients experiencing durable benefit. A targeted therapy-immune checkpoint inhibitor sequencing approach may also be supported by this evidence, but clinical questions regarding optimal timing, duration, and patient selection remain.

Conclusions and Relevance

This review outlines the rationale and preclinical evidence that support immune checkpoint inhibitor plus targeted therapy combination and sequencing strategies in melanoma and highlights the results available to date from clinical trials exploring these approaches to treatment. Several late-stage trials are under way looking to answer open questions in this field and address the continuing debate surrounding up-front combination vs sequencing. As phase 3 data have begun to emerge, trial designs and available data from key studies are discussed in the context of their resultant implications for clinical practice.

Precision medicine in medical oncology: hope, disappointment and reality

During the past 20 years, targeted therapy based on the understanding of tumor biology has been complementing or even replacing cytotoxic agents that have dominated pharmacotherapy of cancer since the conception of medical oncology. Unfortunately, the fact that targeted therapies with potential to induce cure or at least substantially prolong survival are still not available for many common solid tumors results in skepticism or even nihilism. On the one hand, biomarker research is not keeping pace with the introduction of new agents, while on the other hand, effective drugs are still not available for many potential molecular targets associated with malignant transformation and tumor progression. However, targeted therapies have already transformed the natural history and clinical outcomes not only in patients with rare malignancies like gastrointestinal stromal tumor but also with many common tumors, e.g. breast cancer, malignant melanoma, non-small cell lung cancer or renal cell carcinoma. For further advances, a multidisciplinary effort is indispensible that should, above all, involve the collaboration of medical oncology and laboratory medicine.

Regorafenib Versus Nivolumab After Sorafenib Failure: Real-World Data in Patients With Hepatocellular Carcinoma

Regorafenib and nivolumab are drugs approved for second-line treatment of patients with hepatocellular carcinoma (HCC) after sorafenib failure. However, the effectiveness of regorafenib and nivolumab following sorafenib has not been directly compared. This study retrospectively evaluated 373 patients with HCC who were treated with regorafenib (n = 223) or nivolumab (n = 150) after sorafenib failure between July 2017 and February 2019. Progression-free survival (PFS; hazard ratio [HR], 0.85; 95% confidence interval [CI], 0.69-1.06; P = 0.150), time to progression (TTP; HR, 0.95; 95% CI, 0.77-1.19; P = 0.680), and overall survival (OS; HR, 0.83; 95% CI, 0.64-1.07; P = 0.154) did not differ significantly between groups of patients treated with regorafenib and nivolumab, findings consistently observed by multivariable-adjusted, propensity score-matched, and inverse probability treatment weighting (IPTW) analyses. However, the objective response rate was significantly higher in the nivolumab than in the regorafenib group (13.3% vs. 4.0%; P = 0.002). When the effectiveness of regorafenib and nivolumab was compared in nonprogressors to treatment, defined as patients who achieved complete response, partial response, or stable disease after first response evaluation, PFS (HR, 0.50; 95% CI, 0.33-0.75; P = 0.001), TTP (HR, 0.48; 95% CI, 0.31-0.73; P < 0.001), and OS (HR, 0.51; 95% CI, 0.31-0.87; P = 0.013) were significantly longer in the 59 nonprogressors to nivolumab than in the 104 nonprogressors to regorafenib, findings also observed by multivariable-adjusted and IPTW analyses. Conclusion: Survival outcomes in patients treated with regorafenib and nivolumab after sorafenib failure did not differ significantly. However, nivolumab may be more effective than regorafenib in nonprogressors.

Metastatic melanoma: therapeutic agents in preclinical and early clinical development

Introduction: Advanced melanoma historically had a very poor outcome but targeted therapies and immune checkpoint inhibitors (IC) have changed the course of the disease and made durable responses possible. However, most patients will develop progressive disease, so further strategies to overcome treatment resistance are needed. Areas covered: Current treatment strategies and landmark trials are discussed. Novel targeted agents, immune checkpoint inhibitors, and further immune-modulatory drugs, cancer vaccines and tumor infiltrating lymphocytes and their potential role in the treatment of melanoma are described. Current trials investigating these emerging agents and treatment strategies were searched for on ClinicalTrials.gov and are presented on the background of the current literature explaining the rationale for employing these new agents and strategies. Combinations of tumor-directed agents with those causing immune augmentation as well as a new adjuvant and neoadjuvant strategies are discussed. Expert opinion: Questions regarding treatment combination, personalization, and sequence of treatment will become increasingly important and will be guided by new biomarkers. New treatment settings will broaden the patient selection and will highlight the need for further discussions regarding toxicity in long-term survivorship.

Neutrophil-to-Lymphocyte Ratio (NLR), Platelet-to-Lymphocyte Ratio (PLR), and Outcomes with Nivolumab in Pretreated Non-Small Cell Lung Cancer (NSCLC): A Large Retrospective Multicenter Study

INTRODUCTION

Immune checkpoint inhibitors have provided substantial benefit in non-small cell lung cancer (NSCLC) with unprecedented results in terms of survival. However, the identification of reliable predictive biomarkers to these agents is lacking and multiple clinicopathological factors have been evaluated. The aim of this study was to analyze the potential role of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lactate dehydrogenase (LDH) levels in patients with pretreated NSCLC receiving nivolumab.

METHODS

This was a retrospective multicenter study involving 14 Italian centers, evaluating the role of some laboratory results in patients with NSCLC treated with nivolumab in the second or later lines of therapy for at least four doses and with a disease re-staging.

RESULTS

A total of 187 patients with available pretreatment laboratory results were included. NLR levels below 5 were associated with an improvement in terms of both progression-free survival (PFS) (p = 0.028) and overall survival (OS) (p = 0.001), but not in terms of overall response rate (ORR) or disease control rate (DCR). Moreover, PLR levels below 200 were associated with longer PFS (p = 0.0267) and OS (p = 0.05), as well as higher ORR (p = 0.04) and DCR (p = 0.001). In contrast, LDH levels above the upper normal limit (UNL) were not associated with significant impact on patient outcomes.

CONCLUSIONS

Patients with pretreated NSCLC and high pretreatment levels of NLR and PLR may experience inferior outcomes with nivolumab. Therefore, in this subgroup of patients with poor prognosis the use of alternative therapeutic strategies may be a valuable option, especially in programmed cell death ligand 1 (PD-L1)-negative patients and/or in the presence of other additional poor prognostic factors.

Designing Late-Stage Randomized Clinical Trials with Cancer Immunotherapy: Can We Make It Simpler?

The knowledge we have accumulated over the past few years in the field of cancer immunotherapy has prompted the research community to challenge the status quo of trial design and endpoint selection across all drug development phases. For the design of randomized phase III studies using overall survival (OS) as the primary endpoint in particular, the paradigm has shifted from the conventional approach based on a proportional hazards model to those that account for the unique survival kinetics observed in immuno-oncology trials, such as long-term survival and delayed clinical effect. These new approaches usually require complex modeling or simulations, as well as assumptions about the length of delay in clinical effect and the long-term survival rate, making the process of implementing these new designs challenging. Here, a late-stage randomized clinical trial design is proposed based on milestone survival to simplify the process of sample size determination while keeping OS as the primary endpoint. The new design also allows assessment in milestone survival and is unaffected by the uncertainty of the survival kinetics demonstrated by cancer immunotherapies. Cancer Immunol Res; 6(3); 250-4. ©2018 AACR.

Mycobacterium bovis BCG in metastatic melanoma therapy

Melanoma is the most aggressive form of skin cancer, with a high mortality rate and with 96,480 new cases expected in 2019 in the USS. BRAF^V600E, the most common driver mutation, is found in around 50% of melanomas, contributing to tumor growth, angiogenesis, and metastatic progression. Dacarbazine (DTIC), an alkylate agent, was the first chemotherapeutic agent approved by the US Food and Drug Administration (FDA) used as a standard treatment. Since then, immunotherapies have been approved for metastatic melanoma (MM) including ipilimumab and pembrolizumab checkpoint inhibitors that help decrease the risk of progression. Moreover, Mycobacterium bovis Bacillus Calmette-Guerin (BCG) serves as an adjuvant therapy that induces the recruitment of natural killer NK, CD4⁺, and CD8⁺ T cells and contributes to antitumor immunity. BCG can be administered in combination with chemotherapeutic and immunotherapeutic agents and can be genetically manipulated to produce recombinant BCG (rBCG) strains that express heterologous proteins or overexpress immunogenic proteins, increasing the immune response and improving patient survival. In this review, we highlight several studies utilizing rBCG immunotherapy for MM in combination with other therapeutic agents.

Ailanthone Induces Cell Cycle Arrest and Apoptosis in Melanoma B16 and A375 Cells

Malignant melanoma is the most lethal type of skin cancer. Previous studies have shown that ailanthone has potent antitumor activity in a variety of cell lines. However, the anti-tumor effect of ailanthone on malignant melanoma remains unclear. To investigate the anti-tumor mechanisms of ailanthone in human melanoma B16 and mouse melanoma A375 cells, the cell counting kit-8 assay, colony formation assay, DNA content analysis, Hoechst 33258, and Annexin V-FITC/PI staining were used to assess cell proliferation, cell cycle distribution, and cell apoptosis, respectively. Western blotting was performed to evaluate the expression of cell cycle- and apoptosis-related proteins and regulatory molecules. The results showed that ailanthone significantly inhibited melanoma B16 and A375 cell proliferation as well as remarkably induced cell cycle arrest at the G0–G1 phase in B16 cells and the G2–M phase in A375 cells in a dose-dependent manner. Further investigation revealed that ailanthone promoted the expression of p21 and suppressed the expression of cyclin E in B16 cells or cyclin B in A375 cells through the PI3K-Akt signaling pathway. In addition, ailanthone induced B16 and A375 cell apoptosis via a caspase-dependent mechanism. Further studies showed that ailanthone remarkably downregulated Bcl-2 and upregulated Apaf-1 and Bax, and subsequently increased mitochondrial membrane permeabilization and released cytochrome c from the mitochondria in B16 cells and A375 cells. Taken together, ailanthone induces cell cycle arrest via the PI3K-Akt signaling pathway as well as cell apoptosis via the mitochondria-mediated apoptotic signaling pathway. Ailanthone may be potentially utilized as an anti-tumor agent in the management of malignant melanoma.

1-O-alkylglycerols from the hepatopancreas of the crab Paralithodes camtschaticus, liver of the squid Berryteuthis magister, and liver of the skate Bathyraja parmifera, and their anticancer activity on human melanoma cells

1-O-alkylglycerols (AKG) are a class of natural ether lipids derived from 1-O-alkyl-2,3-diacyl-sn-glycerols by deacylation. In this study, 1-O-alkylglycerol (AKG) composition was investigated in the hepatopancreas lipids of the crab Paralithodes camtschaticus and the liver lipids of the squid Berryteuthis magister and the skate  Bathyraja parmifera. One of the principal AKG in marine organisms was 1-O-hexadecyl-sn-glycerol (AKG 16:0). To assess AKG influence on melanoma, we evaluated the cytotoxicity and antiproliferative actions of natural AKG 16:0 and synthetic 1-O-octyl-sn-glycerol (AKG 8:0) on three human melanoma cell lines SK-Mel-5, SK-Mel-28, and RPMI-7951. Natural AKG 16:0 in concentration up to 20 µM was not toxic to all cell lines. AKG 8:0 showed no toxicity to cells SK-Mel-5 and SK-Mel-28 in concentrations up to 20 µM but had moderate cytotoxicity to RPMI-7951 cells with an IC₅₀ of 13 µM. Both investigated substances inhibited the proliferation, formation, and growth of cell colonies of RPMI-7951. PRACTICAL APPLICATIONS: AKG exhibit a variety of biological activities, including anticancer effects. In this study, the liver lipids of the skate B. parmifera and the hepatopancreas lipids of crab P. camtschaticus were shown to be sources of AKG. Our data showed that AKG can be used to prevent the formation of new colonies of malignant cells in combination therapy against melanoma. The results will be useful for future studies involving marine ether lipids and the examination of their anticancer properties against malignant cells.

A practical approach to predict expansion of evidence networks: a case study in treatment-naive advanced melanoma

Network meta-analysis (NMA) is a statistical method used to produce comparable estimates of efficacy across a range of treatments that may not be compared directly within any single trial. NMA feasibility is determined by the comparability of the data and presence of a connected network. In rapidly evolving treatment landscapes, evidence networks can change substantially in a short period of time. We investigate methods to determine the optimum time to conduct or update a NMA based on anticipated available evidence. We report the results of a systematic review conducted in treatment-naive advanced melanoma and compare networks of evidence available at retrospective, current, and prospective time points. For included publications, we compared the primary completion date of trials from clinical trials registries (CTRs) with the date of their first available publication to provide an estimate of publication lag. Using CTRs we were able to produce anticipated networks for future time points based on projected study completion dates and average publication lags which illustrated expansion and strengthening of the initial network. We found that over a snapshot of periods between 2015 and 2018, evidence networks in melanoma changed substantively, adding new comparators and increasing network connectedness. Searching CTRs for ongoing trials demonstrates it is possible to anticipate future networks at a certain time point. Armed with this information, sensible decisions can be made over when best to conduct or update a NMA. Incorporating new and upcoming interventions in a NMA enables presentation of a complete, up-to-date and evolving picture of the evidence.

Arming an Oncolytic Herpes Simplex Virus Type 1 with a Single-chain Fragment Variable Antibody against PD-1 for Experimental Glioblastoma Therapy

PURPOSE

Glioblastoma (GBM) is resistant to standard of care. Immune checkpoints inhibitors (such as anti-PD-1 mAbs) efficiently restore antitumor T-cell activity. We engineered a new oncolytic herpes simplex virus (oHSV) expressing a single-chain antibody against PD-1 (scFvPD-1) to evaluate its efficacy in mouse models of GBM.

EXPERIMENTAL DESIGN

NG34scFvPD-1 expresses the human GADD34 gene transcriptionally controlled by the Nestin promoter to allow replication in GBM cells and a scFvPD-1 cDNA transcriptionally controlled by the CMV promoter. ELISA assays were performed to detect binding of scFvPD-1 to mouse and human PD-1. In vitro cytotoxicity and replication assays were performed to measure NG34scFvPD-1 oncolysis, and scFvPD-1 expression and secretion were determined. In vivo survival studies using orthotopic mouse GBM models were performed to evaluate the therapeutic potency of NG34scFvPD-1.

RESULTS

NG34scFvPD-1-infected GBM cells express and secrete scFvPD-1 that binds mouse PD-1. The introduction of the scFvPD-1 sequence in the viral backbone does not alter the oncolytic properties of NG34scFvPD-1. In situ NG34scFvPD-1 treatment improved the survival with a tail of durable survivorship in 2 syngeneic immunocompetent mouse models of GBM. Mice that survived the first GBM challenge rejected the second challenge of GBM when implanted in the contralateral hemisphere. However, this was not true when athymic mice were employed as the recipients of the second challenge, consistent with the need for an intact immune system to obtain a memory response.

CONCLUSIONS

NG34scFvPD-1 treatment induces a durable antitumor response in 2 preclinical mouse models of GBM with evidence for antitumor memory.

Application of dynamic modeling for survival estimation in advanced renal cell carcinoma

Objective

In oncology, extrapolation of clinical outcomes beyond trial duration is traditionally achieved by parametric survival analysis using population-level outcomes. This approach may not fully capture the benefit/risk profile of immunotherapies due to their unique mechanisms of action. We evaluated an alternative approach—dynamic modeling—to predict outcomes in patients with advanced renal cell carcinoma. We compared standard parametric fitting and dynamic modeling for survival estimation of nivolumab and everolimus using data from the phase III CheckMate 025 study.

Methods

We developed two statistical approaches to predict longer-term outcomes (progression, treatment discontinuation, and survival) for nivolumab and everolimus, then compared these predictions against follow-up clinical trial data to assess their proximity to observed outcomes. For the parametric survival analyses, we selected a probability distribution based on its fit to observed population-level outcomes at 14-month minimum follow-up and used it to predict longer-term outcomes. For dynamic modeling, we used a multivariate Cox regression based on patient-level data, which included risk scores, and probability and duration of response as predictors of longer-term outcomes. Both sets of predictions were compared against trial data with 26- and 38-month minimum follow-up.

Results

Both statistical approaches led to comparable fits to observed trial data for median progression, discontinuation, and survival. However, beyond the trial duration, mean survival predictions differed substantially between methods for nivolumab (30.8 and 51.5 months), but not everolimus (27.2 and 29.8 months). Longer-term follow-up data from CheckMate 025 and phase I/II studies resembled dynamic model predictions for nivolumab.

Conclusions

Dynamic modeling can be a good alternative to parametric survival fitting for immunotherapies because it may help better capture the longer-term benefit/risk profile and support health-economic evaluations of immunotherapies.

Targeting tumour microenvironment by tyrosine kinase inhibitor

Tumour microenvironment (TME) is a key determinant of tumour growth and metastasis. TME could be very different for each type and location of tumour and TME may change constantly during tumour growth. Multiple counterparts in surrounding microenvironment including mesenchymal-, hematopoietic-originated cells as well as non-cellular components affect TME. Thus, therapeutics that can disrupt the tumour-favouring microenvironment should be further explored for cancer therapy. Previous efforts in unravelling the dysregulated mechanisms of TME components has identified numerous protein tyrosine kinases, while its corresponding inhibitors have demonstrated potent modulatory effect on TME. Recent works have demonstrated that beyond the direct action on cancer cells, tyrosine kinase inhibitors (TKIs) have been implicated in inactivation or normalization of dysregulated TME components leading to cancer regression. Either through re-sensitizing the tumour cells or reversing the immunological tolerance microenvironment, the emergence of these TME modulatory mechanism of TKIs supports the combinatory use of TKIs with current chemotherapy or immunotherapy for cancer therapy. Therefore, an appropriate understanding on TME modulation by TKIs may offer another mode of action of TKIs for cancer treatment. This review highlights mode of kinase activation or paracrine ligand production from TME components and summarises the findings on the potential use of various TKIs on regulating TME components. At last, the combination use of current TKIs with immunotherapy in the perspectives of efficacy and safety are discussed.

A novel compound which sensitizes BRAF wild-type melanoma cells to vemurafenib in a TRIM16-dependent manner

There is an urgent need for better therapeutic options for advanced melanoma patients, particularly those without the BRAFV600E/K mutation. In melanoma cells, loss of TRIM16 expression is a marker of cell migration and metastasis, while the BRAF inhibitor, vemurafenib, induces melanoma cell growth arrest in a TRIM16-dependent manner. Here we identify a novel small molecule compound which sensitized BRAF wild-type melanoma cells to vemurafenib. High throughput, cell-based, chemical library screening identified a compound (C012) which significantly reduced melanoma cell viability, with limited toxicity for normal human fibroblasts. When combined with the BRAFV600E/K inhibitor, vemurafenib, C012 synergistically increased vemurafenib potency in 5 BRAFWT and 4 out of 5 BRAFV600E human melanoma cell lines (Combination Index: CI < 1), and, dramatically reduced colony forming ability. In addition, this drug combination was significantly anti-tumorigenic in vivo in a melanoma xenograft mouse model. The combination of vemurafenib and C012 markedly increased expression of TRIM16 protein, and knockdown of TRIM16 significantly reduced the growth inhibitory effects of the vemurafenib and C012 combination. These findings suggest that the combination of C012 and vemurafenib may have therapeutic potential for the treatment of melanoma, and, that reactivation of TRIM16 may be an effective strategy for patients with this disease.

Immune Checkpoint Inhibitors (ICIs) in Non-Small Cell Lung Cancer (NSCLC)

Cancer immunotherapy with immune checkpoint inhibitors (ICIs) has become a "game changer" in the treatment of advanced non-small cell lung cancer (NSCLC). Its most clinically important advantage over traditional chemotherapy using cytotoxic agents are its long-term survival benefits, and some advanced NSCLC patients treated with an antibody against programmed cell death 1 (PD-1) have survived for 5 years or longer. Immune checkpoint inhibitors (ICIs) are also potentially useful for earlier-stage NSCLC when used in combination with surgery or radiotherapy. A recent clinical trial has shown that consolidation treatment with an antibody against a ligand of PD-1 (PD-L1) following chemo-radiotherapy significantly improves progression-free survival for patients with locally advanced NSCLC. However, current single-agent treatment with an anti-PD-1/PD-L1 antibody may provide significant survival benefits only in a small subset of patients. PD-L1 expression status on tumor cells is an approved biomarker to predict response to ICIs, but is not enough for optimal patient selection. To improve the therapeutic outcomes, development of novel biomarkers other than PD-L1 expression status is essential. Combination treatment strategies based on blockade of PD-1/PD-L1 may also be promising, and a variety of combinations, such as ICIs plus chemotherapy, are being examined in ongoing clinical trials. Here we review and discuss the current status and future perspectives of immunotherapy with ICIs.

Future perspectives in melanoma research "Melanoma Bridge", Napoli, November 30th-3rd December 2016

Major advances have been made in the treatment of cancer with targeted therapy and immunotherapy; several FDA-approved agents with associated improvement of 1-year survival rates became available for stage IV melanoma patients. Before 2010, the 1-year survival were quite low, at 30%; in 2011, the rise to nearly 50% in the setting of treatment with Ipilimumab, and rise to 70% with BRAF inhibitor monotherapy in 2013 was observed. Even more impressive are 1-year survival rates considering combination strategies with both targeted therapy and immunotherapy, now exceeding 80%. Can we improve response rates even further, and bring these therapies to more patients? In fact, despite these advances, responses are heterogeneous and are not always durable. There is a critical need to better understand who will benefit from therapy, as well as proper timing, sequence and combination of different therapeutic agents. How can we better understand responses to therapy and optimize treatment regimens? The key to better understanding therapy and to optimizing responses is with insights gained from responses to targeted therapy and immunotherapy through translational research in human samples. Combination therapies including chemotherapy, radiotherapy, targeted therapy, electrochemotherapy with immunotherapy agents such as Immune Checkpoint Blockers are under investigation but there is much room for improvement. Adoptive T cell therapy including tumor infiltrating lymphocytes and chimeric antigen receptor modified T cells therapy is also efficacious in metastatic melanoma and outcome enhancement seem likely by improved homing capacity of chemokine receptor transduced T cells. Tumor infiltrating lymphocytes therapy is also efficacious in metastatic melanoma and outcome enhancement seem likely by improved homing capacity of chemokine receptor transduced T cells. Understanding the mechanisms behind the development of acquired resistance and tests for biomarkers for treatment decisions are also under study and will offer new opportunities for more efficient combination therapies. Knowledge of immunologic features of the tumor microenvironment associated with response and resistance will improve the identification of patients who will derive the most benefit from monotherapy and might reveal additional immunologic determinants that could be targeted in combination with checkpoint blockade. The future of advanced melanoma needs to involve education and trials, biobanks with a focus on primary tumors, bioinformatics and empowerment of patients and clinicians.

Management of intracranial melanomas in the era of precision medicine

Melanoma is the most lethal of skin cancers, in part because of its proclivity for rapid and distant metastasis. It is also potentially the most neurotropic cancer in terms of probability of CNS metastasis from the primary lesion. Despite surgical resection and radiotherapy, prognosis remains guarded for patients with brain metastases. Over the past five years, a new domain of personalized therapy has emerged for advanced melanoma patients with the introduction of BRAF and other MAP kinase pathway inhibitors, immunotherapy, and combinatory therapeutic strategies. By targeting critical cellular signaling pathways and unleashing the adaptive immune response against tumor antigens, a subset of melanoma patients have demonstrated remarkable responses to these treatments. Over time, acquired resistance to these modalities inexorably develops, providing new challenges to overcome. We review the rapidly evolving terrain for intracranial melanoma treatment, address likely and potential mechanisms of resistance, as well as evaluate promising future therapeutic approaches currently under clinical investigation.

Dynamic versus static biomarkers in cancer immune checkpoint blockade: unravelling complexity

Recently, there has been a coordinated effort from academic institutions and the pharmaceutical industry to identify biomarkers that can predict responses to immune checkpoint blockade in cancer. Several biomarkers have been identified; however, none has reliably predicted response in a sufficiently rigorous manner for routine use. Here, we argue that the therapeutic response to immune checkpoint blockade is a critical state transition of a complex system. Such systems are highly sensitive to initial conditions, and critical transitions are notoriously difficult to predict far in advance. Nevertheless, warning signals can be detected closer to the tipping point. Advances in mathematics and network biology are starting to make it possible to identify such warning signals. We propose that these dynamic biomarkers could prove to be useful in distinguishing responding from non-responding patients, as well as facilitate the identification of new therapeutic targets for combination therapy.

Intramammary metastatic melanoma of unknown primary origin in a 58-year old patient: a case report

BACKGROUND

Malignant melanoma metastasis to the breast is a rare disease.

CASE PRESENTATION

We present the case of a 58-year-old postmenopausal Caucasian woman with metastatic malignant melanoma of unknown origin of the right breast. She presented with a palpable lump in the inferior quadrant of her right breast. The investigations concluded it was breast metastasis from a malignant melanoma of unknown origin. The treatment consisted of mastectomy and axillary lymph node dissection. Two lymph nodes were positive for tumor cells and one showed extracapsular extension. Our patient did not receive immediate adjuvant therapy. Six weeks after the surgery, our patient presented a relapse in the right axilla (a 6 × 4 cm mass) with positive internal mammary lymph nodes and a single brain metastasis. This relapse motivated an adjuvant treatment with partial regression of the disease. Currently, our patient presents multiple metastases with poor prognosis.

CONCLUSIONS

From this experience, we advocate an immediate aggressive handling of melanoma metastasis to the breast.

Convection-enhanced Delivery of Therapeutics for Malignant Gliomas

Convection-enhanced delivery (CED) circumvents the blood–brain barrier by delivering agents directly into the tumor and surrounding parenchyma. CED can achieve large volumes of distribution by continuous positive-pressure infusion. Although promising as an effective drug delivery method in concept, the administration of therapeutic agents via CED is not without challenges. Limitations of distribution remain a problem in large brains, such as those of humans. Accurate and consistent delivery of an agent is another challenge associated with CED. Similar to the difficulties caused by immunosuppressive environments associated with gliomas, there are several mechanisms that make effective local drug distribution difficult in malignant gliomas. In this review, methods for local drug application targeting gliomas are discussed with special emphasis on CED. Although early clinical trials have failed to demonstrate the efficacy of CED against gliomas, CED potentially can be a platform for translating the molecular understanding of glioblastomas achieved in the laboratory into effective clinical treatments. Several clinical studies using CED of chemotherapeutic agents are ongoing. Successful delivery of effective agents should prove the efficacy of CED in the near future.

Neoadjuvant treatment for melanoma: current challenges and future perspectives

There will be an estimated 76,100 new cases of melanoma diagnosed in 2015 and 9710 deaths. Patients with stage I/II disease have excellent outcomes, and the treatment landscape for patients with metastatic disease has been transformed by the approval of several immune checkpoint inhibitors and molecular targeted therapies. Patients with stage III disease, however, continue to have very limited options, as the only agent shown to improve survival in the adjuvant setting is high-dose IFN-α. Neoadjuvant trials of chemotherapy and chemobiotherapy have not been successful, and while neoadjuvant ipilimumab and high-dose interferon have shown promise in small trials, neither agent has been approved. Current trials are testing immune therapy and targeted therapy combinations in the neoadjuvant setting.

Predicting analysis times in randomized clinical trials with cancer immunotherapy

Background

A new class of immuno-oncology agents has recently been shown to induce long-term survival in a proportion of treated patients. This phenomenon poses unique challenges for the prediction of analysis time in event-driven studies. If the phenomenon of long-term survival is not accounted for properly, the accuracy of the prediction based on the existing methods may be substantially compromised.

Methods

Parametric mixture cure rate models with the best fit to empirical clinical trial data were proposed to predict analysis times in immuno-oncology studies during the course of the study. The proposed prediction procedure also accounts for the mechanism of action introduced by cancer immunotherapies, such as delayed and long-term survival effects.

Results

The proposed methodology was retrospectively applied to a randomized phase III immuno-oncology clinical trial. Among various parametric mixture cure rate models, the Weibull cure rate model was found to be the best-fitting model for this study. The unique survival kinetics of cancer immunotherapy was captured in the longitudinal predictions of the final analysis times.

Conclusions

Parametric mixture cure rate models, along with estimated long-term survival rates, probabilities of study incompletion, and expected statistical powers over time, provide immuno-oncology clinical trial researchers with a useful tool for continuous event monitoring and prediction of analysis times, such that informed decisions with quantifiable risks can be made for better resource and logistic planning.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-016-0117-3) contains supplementary material, which is available to authorized users.

The challenges and the promise of molecular targeted therapy in malignant gliomas

Malignant gliomas are the most common malignant primary brain tumors and one of the most challenging forms of cancers to treat. Despite advances in conventional treatment, the outcome for patients remains almost universally fatal. This poor prognosis is due to therapeutic resistance and tumor recurrence after surgical removal. However, over the past decade, molecular targeted therapy has held the promise of transforming the care of malignant glioma patients. Significant progress in understanding the molecular pathology of gliomagenesis and maintenance of the malignant phenotypes will open opportunities to rationally develop new molecular targeted therapy options. Recently, therapeutic strategies have focused on targeting pro-growth signaling mediated by receptor tyrosine kinase/RAS/phosphatidylinositol 3-kinase pathway, proangiogenic pathways, and several other vital intracellular signaling networks, such as proteasome and histone deacetylase. However, several factors such as cross-talk between the altered pathways, intratumoral molecular heterogeneity, and therapeutic resistance of glioma stem cells (GSCs) have limited the activity of single agents. Efforts are ongoing to study in depth the complex molecular biology of glioma, develop novel regimens targeting GSCs, and identify biomarkers to stratify patients with the individualized molecular targeted therapy. Here, we review the molecular alterations relevant to the pathology of malignant glioma, review current advances in clinical targeted trials, and discuss the challenges, controversies, and future directions of molecular targeted therapy.

Milestone Survival: A Potential Intermediate Endpoint for Immune Checkpoint Inhibitors

Recent advancements in cancer immunotherapies offer diverse strategies for cancer treatment. Among the most promising approaches is the blockade of immune checkpoint molecules to activate antitumor immunity. With targeted immunotherapies of new mechanisms of action come greater challenges in study design and statistical analysis, as well as the need for refining clinical trial endpoints. The long-term survival and delayed clinical effects demonstrated by these therapies could result in substantial prolongation of study duration and loss of statistical power if these key attributes are not accounted for in the study design and statistical analyses. In the Brookings Conference on Clinical Cancer Research held in Washington, DC, in November 2013, several intermediate clinical endpoints, including milestone overall survival, were proposed for the evaluation of cancer immunotherapies to take into account the possibility of delayed treatment effect and to better characterize the clinical activity profile of such agents, particularly immune checkpoint inhibitors. In this manuscript, the use of milestone survival is described as a potential efficacy endpoint for immune checkpoint inhibitors in late-stage drug development that could potentially mitigate the challenge of accelerating the drug development process when the strength of this class of agents is derived from long-term follow-up.

Which Metrics Are Appropriate to Describe the Value of New Cancer Therapies?

Patients with certain cancers are treated with curative intent, but for others the results are less favorable and different therapeutic approaches are needed. Early data suggest that new therapies, which modulate immune responses to cancers, may have potential for long-term survival in a proportion of cases. Therefore, it is timely to consider whether metrics generally used to describe the medical value of therapies for patients with common solid tumors remain appropriate for therapies with curative potential. Literature reviews were conducted to define how various stakeholders describe cure in oncology and to identify the endpoints used in clinical trials for selected solid tumors. The results showed that “cure” is described using various terms that can be divided broadly into lack of disease progression, eradication of cancerous cells, and survival. The review of trial endpoints showed frequent use of median overall survival (OS) and progression- and response-related endpoints. Because these endpoints were mainly described in the context of chemotherapies that are not generally curative, they may not adequately capture outcomes of new therapeutic modalities with potential for long-term survival. More appropriate endpoints may include mean OS, cure fraction, and OS rate at landmark time points.

Treatment patterns and outcomes in BRAF V600E-mutant melanoma patients with brain metastases receiving vemurafenib in the real-world setting

Brain metastases are a common and serious complication among patients with metastatic melanoma. The selective BRAF inhibitor vemurafenib has demonstrated clinical efficacy in patients with BRAF V600E-mutant melanoma brain metastases (MBM). We examined the real-world application and clinical outcomes of vemurafenib in this patient population. Demographic, treatment patterns, response, and survival data were collected from medical charts. Clinical data on 283 patients with active BRAF V600E-mutant MBM treated with vemurafenib were provided by 70 US oncologists. Mean age was 57.2 years, 60.8% were male, 67.5% had ECOG performance status of 0–1, and 43.1% used corticosteroids at vemurafenib initiation. Median follow-up was 5.7 months. Following vemurafenib initiation, 48.1% of patients experienced intracranial response and 45.6% experienced extracranial response. The Kaplan–Meier estimate for overall survival was 59% at 12 months. Multivariate analyses showed associations between intracranial response and both corticosteroid use and vemurafenib as initial therapy after MBM diagnosis. Larger size (5–10 mm vs. <5 mm) and number of brain metastases (≥5 vs. <2) and progressive extracranial disease at treatment initiation were associated with decreased intracranial response and increased risk of disease progression. Multiple extracranial sites (2 vs. <2) and the absence of local treatments were also associated with increased risk of progression. Increased risk of death was associated with ≥2 extracranial disease sites, progressive extracranial disease, and ≥5 brain metastases. Subgroups of MBM patients may derive more benefit with vemurafenib, warranting prospective investigation.

The Ruesch Center Symposium 2014: Fighting a Smarter War against Cancer Using Immunotherapy

The Ruesch Cancer Symposium, Washington DC, USA, 4–6 December 2014

Cancer immunotherapy: a future paradigm shift in the treatment of non-small cell lung cancer

Emerging evidence on the role of the antitumor activity of the immune system has generated great interest in immunotherapy even for tumors that were historically considered as nonimmunogenic. Immunotherapy is emerging as a major modality in non-small cell lung cancer (NSCLC) treatment focusing on vaccine approaches to elicit specific immune responses and development of inhibitors of the molecular mediators of cancer-induced immunosuppression (immune checkpoints) to boost antitumor immune responses. Amplification of the host response against evolving tumors through vaccination is being investigated in ongoing clinical trials with tumor cell vaccines; however, the clinical efficacy of these agents has been limited. Blocking inhibitory pathways such as the CTL antigen 4 (CTLA-4) and programmed cell death 1 (PD-1) checkpoint pathways with mAbs has generated antitumor immune responses that are transforming cancer therapeutics. PD-1 and programmed cell death ligand 1 (PD-L1) antibodies have shown durable responses in NSCLC, with a favorable safety profile and manageable side effects. The activity of immune checkpoint inhibitors is currently been assessed in treatment-naïve patients with PD-L1-positive advanced NSCLC. Combinatorial approaches with other immune checkpoint inhibitors, chemotherapy, or targeted agents are being explored in ongoing clinical trials, and may improve outcome in NSCLC.

Humoral Immune Response against Nontargeted Tumor Antigens after Treatment with Sipuleucel-T and Its Association with Improved Clinical Outcome

PURPOSE

Antitumor activity of cancer immunotherapies may elicit immune responses to nontargeted (secondary) tumor antigens, or antigen spread. We evaluated humoral antigen spread after treatment with sipuleucel-T, an immunotherapy for asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC), designed to target prostatic acid phosphatase (PAP; primary antigen).

EXPERIMENTAL DESIGN

Serum samples from patients with mCRPC enrolled in the placebo-controlled phase III IMPACT study (evaluable n = 142) were used to assess humoral antigen spread after treatment with sipuleucel-T. Immunoglobulin G (IgG) responses to self-antigens (including tumor antigens) were surveyed using protein microarrays and confirmed using Luminex xMAP. IgG responses were subsequently validated in ProACT (n = 33), an independent phase II study of sipuleucel-T. Association of IgG responses with overall survival (OS) was assessed using multivariate Cox models adjusted for baseline prostate-specific antigen (PSA) and lactate dehydrogenase levels.

RESULTS

In patients from IMPACT and ProACT, levels of IgG against multiple secondary antigens, including PSA, KLK2/hK2, K-Ras, E-Ras, LGALS8/PCTA-1/galectin-8, and LGALS3/galectin-3, were elevated after treatment with sipuleucel-T (P < 0.01), but not control. IgG responses (≥ 2-fold elevation posttreatment) occurred in ≥ 25% of patients, appeared by 2 weeks after sipuleucel-T treatment, and persisted for up to 6 months. IgG responses to PSA and LGALS3 were associated with improved OS in sipuleucel-T-treated patients from IMPACT (P ≤ 0.05).

CONCLUSIONS

Sipuleucel-T induced humoral antigen spread in patients with mCRPC. IgG responses were associated with improved OS in IMPACT. The methods and results reported may identify pharmacodynamic biomarkers of clinical outcome after sipuleucel-T treatment, and help in clinical assessments of other cancer immunotherapies. See related commentary by Hellstrom and Hellstrom, p. 3581.

Targeted therapies in melanoma

Advances in the biology of melanoma have provided insights about chemoresistance and its genetic heterogeneity in parallel with advances in drug design, culminating in recent major treatment breakthroughs. Although clinical benefit of targeted therapies has been unquestionable, future advances are only possible if we understand the interplay between genetic aberrations and role of other crucial nongenetic changes yet to be identified by such projects as the Cancer Genome Atlas Project in Melanoma. Combination therapies, either among small molecule inhibitors themselves and/or with immunotherapies, may be the optimal strategy to prevent development of drug resistance inherently linked with such targeted therapies.

The role of immunotherapy in solid tumors: report from the Campania Society of Oncology Immunotherapy (SCITO) meeting, Naples 2014

The therapeutic approach to advanced or metastatic solid tumors, either with chemotherapy or targeted therapies, is mainly palliative. Resistance to chemotherapy occurs very frequently and is one of the most important reasons for disease progression. Immunotherapy has the potential to mount an ongoing, dynamic immune response that can kill tumor cells for an extended time after the conventional therapy has been administered. Such a long-lasting response is potentially able to completely eradicate tumor cells, rather than producing only a temporary killing of cells. The most promising immune-based treatments are monoclonal antibodies that act as checkpoint inhibitors (e.g. ipilimumab and nivolumab), adoptive cell therapy (e.g. T-cells expressing chimeric antigen receptors) and vaccines (e.g. sipuleucel-T). Ipilimumab is currently approved for the treatment of metastatic melanoma and sipuleucel-T is approved for advanced prostate cancer. There is great interest in immunotherapy in other solid tumors, potentially used alone or in a multimodal fashion with chemotherapy and/or biological drugs. In this paper, we review recent advances in immuno-oncology in solid malignancies (except melanoma) as were discussed at the inaugural meeting of the Campania Society of Oncology Immunotherapy (SCITO).