Efficacy and immune-related adverse event associations in avelumab-treated patients

Breast Cancer Treatment Strategies Targeting the Tumor Microenvironment: How to Convert "Cold" Tumors to "Hot" Tumors

Breast cancer characterized as "cold tumors" exhibit low levels of immune cell infiltration, which limits the efficacy of conventional immunotherapy. Recent studies have focused on strategies using nanotechnology combined with tumor microenvironment modulation to transform "cold tumors" into "hot tumors". This approach involves the use of functionalized nanoparticles that target and modify the tumor microenvironment to promote the infiltration and activation of antitumor immune cells. By delivering immune activators or blocking immunosuppressive signals, these nanoparticles activate otherwise dormant immune responses, enhancing tumor immunogenicity and the therapeutic response. These strategies not only promise to increase the response rate of breast cancer patients to existing immunotherapies but also may pave new therapeutic avenues, providing a new direction for the immunotherapy of breast cancer.

Avelumab in the Treatment of Advanced Merkel Cell Carcinoma: A Systematic Review

BACKGROUND

Avelumab, a programmed death ligand-1 inhibitor, has shown success in providing durable responses for difficult-to-treat Merkel cell carcinomas (MCCs).

OBJECTIVE

Evaluate the efficacy and safety of avelumab in the treatment of advanced MCC.

METHODS

Studies reporting the use of avelumab as a monotherapy or in combination with other agents in the treatment of stage III or IV (advanced) MCC were included. The primary outcomes were overall response rate, overall survival (OS), and treatment-related adverse events.

RESULTS

A total of 48 studies were included, involving 1,565 patients with advanced MCC. Most patients were male (1,051, 67.3%) with stage IV MCC (517, 97.0%). The overall response rate was 46.1% (partial response-25.4% and complete response-20.7%) after a mean follow-up period of 9.5 months. Kaplan-Meier survival curves for the pooled stage III and IV group demonstrated OS rates of 58% at 1 year, 47% at 2 years, and 28% at 5 years after completion of treatment with avelumab (median OS: 23.1 months). The most common treatment-related adverse events consisted of constitutional (44%), gastrointestinal (19%), and dermatologic (12%) symptoms.

CONCLUSION

Avelumab monotherapy and combination therapy have shown success in the overall response rate and survival for patients with advanced MCC.

Redefining the battle against colorectal cancer: a comprehensive review of emerging immunotherapies and their clinical efficacy

Colorectal cancer (CRC) is the third most common cancer globally and presents a significant challenge owing to its high mortality rate and the limitations of traditional treatment options such as surgery, radiotherapy, and chemotherapy. While these treatments are foundational, they are often poorly effective owing to tumor resistance. Immunotherapy is a groundbreaking alternative that has recently emerged and offers new hope for success by exploiting the body's own immune system. This article aims to provide an extensive review of clinical trials evaluating the efficacy of various immunotherapies, including CRC vaccines, chimeric antigen receptor T-cell therapies, and immune checkpoint inhibitors. We also discuss combining CRC vaccines with monoclonal antibodies, delve into preclinical studies of novel cancer vaccines, and assess the impact of these treatment methods on patient outcomes. This review seeks to provide a deeper understanding of the current state of CRC treatment by evaluating innovative treatments and their potential to redefine the prognosis of patients with CRC.

Effects of immune-related adverse events (irAEs) and their treatment on antitumor immune responses

Immune checkpoint inhibitors (ICIs) are potentially life-saving cancer therapies that can trigger immune-related adverse events (irAEs). irAEs can impact any organ and range in their presentation from mild side effects to life-threatening complications. The relationship between irAEs and antitumor immune responses is nuanced and may depend on the irAE organ, the tumor histology, and the patient. While some irAEs likely represent an immune response against antigens shared between tumor cells and healthy tissues, other irAEs may be entirely unrelated to antitumor immune responses. Clinical observations suggest that low-grade irAEs have a positive association with responses to ICIs, but the correlation between severe irAEs and clinical benefit is less clear. Currently, severe irAEs are typically treated by interrupting or permanently discontinuing ICI treatment and administering empirically selected systemic immunosuppressive agents. However, these interventions could potentially diminish the antitumor effects of ICIs. Efforts to understand the mechanistic relationship between irAEs and the tumor microenvironment have yielded meaningful insights and nominated therapeutic targets for irAE management that may preserve or even boost ICI efficacy. We explore the clinical and molecular relationship between irAEs and antitumor immunity as well as the role that irAE treatments may play in shaping antitumor immune responses.

Association between immune-mediated adverse events and efficacy in metastatic non-small-cell lung cancer patients treated with durvalumab and tremelimumab

PURPOSE

Immune-mediated adverse events (imAEs) may be associated with response to immune checkpoint inhibitors. We assessed the relationship between imAE development and efficacy in metastatic non-small-cell lung cancer patients treated with durvalumab (anti-programmed cell death ligand-1 [PD-L1]) alone or in combination with tremelimumab (anti-cytotoxic T-lymphocyte-associated protein 4).

METHODS

The analysis used individual patient-level data from 307 and 310 patients in the monotherapy and combination arms of MYSTIC, respectively. We evaluated the association between treatment efficacy and development of imAEs using univariate and multivariate survival analyses. Using machine learning, we built a predictive model utilizing baseline clinical and laboratory features to identify patients at risk of developing imAEs and further evaluated patient survival based on a threshold index extracted from the model.

RESULTS

Patients who developed any grade of imAE had improved overall survival versus patients without (hazard ratio [HR] 0.51; 95% confidence interval [CI]: 0.41-0.62). imAE development was associated with improved overall survival (HR 0.54; 95% CI 0.44-0.66) in a multivariate Cox proportional hazard model considering patient demographic features and baseline characteristics. Higher odds of imAE development were observed (odds ratio 3.023; 95% CI: 1.56-5.83) in responders versus non-responders in patients treated with immunotherapy. Based on baseline characteristics, the random forest classification algorithm was used to formulate a predictive model to identify patients at increased risk of developing imAEs during treatment.

CONCLUSION

Post-hoc exploratory analysis found that the efficacy of immunotherapy was improved in patients who developed on-treatment imAEs. This was independent of severity of imAEs or the need for steroid treatment, which is important in allowing patients to remain on treatment and derive optimal clinical benefit. Further research is warranted to establish the correlation between incidence of imAEs and efficacy in this patient population.

Mechanisms of dermatologic toxicities to immune checkpoint inhibitor cancer therapies

The discovery of immune checkpoint inhibition (ICI) sparked a revolution in the era of targeted anticancer therapy. While monoclonal antibodies targeting the CTLA-4 and PD-1 axes have improved survival in patients with advanced cancers, these immunotherapies are associated with a wide spectrum of dermatologic immune-related adverse events (irAEs). Several publications have addressed the clinical and histopathologic classification of these skin-directed irAEs, their impact on antitumor immunity and survival, and the critical role of supportive oncologic dermatology in their management. Here, we review the current understanding of the mechanistic drivers of immune-related skin toxicities with a focus on inflammatory, immunobullous, melanocyte/pigment-related reactions. We detail the specific immune-based mechanisms that may underlie different cutaneous reactions. We also discuss potential mechanisms as they relate to non-cutaneous irAEs and potential overlap with cutaneous irAEs, techniques to study differences in immune-related versus de novo skin reactions, and how treatment of these adverse events impacts cancer treatment, patient quality of life, and overall survival. An improved understanding of the mechanistic basis of cutaneous irAEs will allow us to develop and utilize blood-based biomarkers that could help ultimately predict onset and/or severity of these irAEs and to implement rational mechanistic-based treatment strategies that are targeted to the irAEs while potentially avoiding abrogating anti-tumor effect of ICIs.

Harnessing big data to characterize immune-related adverse events

Immune-checkpoint inhibitors (ICIs) have transformed patient care in oncology but are associated with a unique spectrum of organ-specific inflammatory toxicities known as immune-related adverse events (irAEs). Given the expanding use of ICIs, an increasing number of patients with cancer experience irAEs, including severe irAEs. Proper diagnosis and management of irAEs are important to optimize the quality of life and long-term outcomes of patients receiving ICIs; however, owing to the substantial heterogeneity within irAEs, and despite multicentre initiatives, performing clinical studies of these toxicities with a sufficient cohort size is challenging. Pioneering studies from the past few years have demonstrated that aggregate clinical data, real-world data (such as data on pharmacovigilance or from electronic health records) and multi-omics data are alternative tools well suited to investigating the underlying mechanisms and clinical presentations of irAEs. In this Perspective, we summarize the advantages and shortcomings of different sources of 'big data' for the study of irAEs and highlight progress made using such data to identify biomarkers of irAE risk, evaluate associations between irAEs and therapeutic efficacy, and characterize the effects of demographic and anthropometric factors on irAE risk. Harnessing big data will accelerate research on irAEs and provide key insights that will improve the clinical management of patients receiving ICIs.

Associations between immune-related thyroid dysfunction and efficacy of immune checkpoint inhibitors: a systematic review and meta-analysis

BACKGROUND

There is growing evidence suggesting that the occurrence of immune-related adverse events (irAEs) may be a predictor of immune checkpoint inhibitor efficacy. Whether this association extends to all irAEs or just those within particular organs/systems is yet to be resolved. As immune-related thyroid dysfunction (thyroid irAE) is one of the most commonly reported irAEs, this study aims to summarize the available data and determine if thyroid irAE is a surrogate marker for improved cancer outcomes during ICI therapy.

METHODS

PubMed, EMBASE and Cochrane Library were searched up to July 1st 2021 for studies assessing the relationship between thyroid irAE development during ICI therapy and cancer outcomes. Outcome measures of interest include overall survival (OS) and progression free survival (PFS). Sub-group analyses based on cancer type and adjustment for immortal time bias (ITB) were also performed.

RESULTS

Forty-seven studies were included in the systematic review. Twenty-one studies were included in the OS meta-analysis whilst 15 were included in the PFS meta-analysis. Development of thyroid irAE during ICI therapy was associated with improved OS and PFS (OS: HR 0.52, CI 0.43-0.62, p < 0.001; PFS: HR 0.58, CI 0.50-0.67, p < 0.001). Sub-group analyses involving non-small cell lung cancer populations and studies where ITB was accounted for, observed similar results (HR 0.37, CI 0.24-0.57, p < 0.001) and (HR 0.51, CI 0.39-0.69, p < 0.001), respectively.

CONCLUSION

Despite the heterogeneity and biases identified, the evidence does suggest that the development of thyroid irAE is associated with anti-tumor effects of ICIs and therefore, can be used as a surrogate marker for clinical response.

Defining the correlation between immune-checkpoint inhibitors-related adverse events and clinical outcomes: a narrative review

Immune checkpoint inhibitors (ICIs) have increased modern anticancer armamentarium portfolios, with 15%-60% of cancer patients deriving clinical benefit while others progress, including some occurrences of accelerated progressions. ICIs have also introduced a new pattern of immune-related adverse events (irAEs). Recently, a mechanistic link was proposed in which patients who develop ICIs-related irAEs derive a survival benefit compared to those who do not, suggesting an overlap between toxicities and the treatment efficacy. Identifying predictive biomarkers to optimally identify patients who will benefit from ICIs is a contemporary research area in Oncology. However, the data remains sparse, with only several smaller studies showing a plausible direct proportionality of a therapeutic effect across tumours. In contrast, the overall survival and progression-free survival rate depend on the tumour type, degree of toxicities, duration of exposure, affected system/organs and inherent patient characteristics. Furthermore, the occurrence of irAEs appears to be more associated with a clinical benefit from programmed death 1 and programmed death-ligand 1 inhibitors than anti-cytotoxic T-lymphocyte-associated antigen 4. Several questions remain unanswered, including the association between survival benefit and specific type of organ system toxicities, toxicity grade, if the benefit is entirely due to immortal-time biases (ITBs), presence of patients confounding comorbidities like autoimmune diseases, and finally, immune heterogeneities. Considering ITB represents a key element in interpreting these studies since patients with precipitated death or with an earlier disease progresses rarely develop irAEs; in fact, such patients have not stayed in the study long enough to experience such irAEs. Conversely, patients that stayed in the study for a longer period have a higher risk of developing irAEs. Landmark analysis is key in these studies if a real association is to be found. Overall response and disease control rates are mainly higher in those who develop irAEs due to immune activation. So, this review aims to summarise the evidence from key studies that addressed this important clinical question.

Emerging combination immunotherapy strategies for breast cancer: dual immune checkpoint modulation, antibody-drug conjugates and bispecific antibodies

Breast cancer has historically been considered a non-immunogenic tumor. Multiple studies over the last 10-15 years have demonstrated that a small subset of breast cancers is immune-activated, with PD-L1 expression and/or TILs in the tumor microenvironment. The PD-1 inhibitor pembrolizumab in combination with chemotherapy is now approved by the US FDA for the first-line treatment of metastatic PD-L1 + triple negative breast cancer, and the PD-L1 inhibitor atezolizumab has also demonstrated clinical activity. The median progression-free survival for pembrolizumab or atezolizumab combined with chemotherapy increased with the addition of immunotherapy by 4.1 months and 2.5 months, respectively. Despite this success, there is major room for improvement. Clinical benefit is modest. Only about 40% of triple negative breast cancers are PD-L1 + , not all PD-L1 + patients with advanced triple negative breast cancer respond, and immunotherapy is not yet approved for advanced PD-L1-negative triple negative breast cancer, HER2 + breast cancer, or ER + breast cancer. It is likely that redundant pathways of immune suppression are active in breast cancer, or that important pathways of immune activation are silent. In this review, we discuss emerging strategies for targeting multiple pathways of immunoregulation in advanced breast cancer with dual immune checkpoint inhibition, bispecific antibodies, and novel antibody drug conjugates. We also discuss the potential of nanotechnology to improve the delivery of immunotherapeutics to the breast tumor microenvironment to enhance their antitumor activity.

Activity of ipilimumab plus nivolumab in avelumab-refractory Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine cutaneous malignancy with poor prognosis. In Europe, approved systemic therapies are limited to the PD-L1 inhibitor avelumab. For avelumab-refractory patients, efficient and safe treatment options are lacking.

METHODS

At three different sites in Germany, clinical and molecular data of patients with metastatic MCC being refractory to the PD-L1 inhibitor avelumab and who were later on treated with combined IPI/NIVO were retrospectively collected and evaluated.

RESULTS

Five patients treated at three different academic sites in Germany were enrolled. Three out of five patients investigated for this report responded to combined IPI/NIVO according to RECIST 1.1. Combined immunotherapy was well tolerated without any grade II or III immune-related adverse events. Two out of three responders to IPI/NIVO received platinum-based chemotherapy in between avelumab and combined immunotherapy.

CONCLUSION

In this small retrospective study, we observed a high response rate and durable responses to subsequent combined immunotherapy with IPI/NIVO in avelumab-refractory metastatic MCC patients. In conclusion, our data suggest a promising activity of second- or third-line PD-1- plus CTLA-4-blockade in patients with anti-PD-L1-refractory MCC.