Increased Soluble PD-1 Predicts Response to Nivolumab plus Ipilimumab in Melanoma.

BACKGROUND: Checkpoint inhibitors have revolutionized the treatment of metastatic melanoma, yielding long-term survival in a considerable proportion of the patients. Yet, 40-60% of patients do not achieve a long-term benefit from such therapy, emphasizing the urgent need to identify biomarkers that can predict response to immunotherapy and guide patients for the best possible treatment. Here, we exploited an unsupervised machine learning approach to identify potential inflammatory cytokine signatures from liquid biopsies, which could predict response to immunotherapy in melanoma. METHODS: We studied a cohort of 77 patients diagnosed with unresectable advanced-stage melanoma undergoing treatment with first-line nivolumab plus ipilimumab or pembrolizumab. Baseline and on-treatment plasma samples were tested for levels of PD-1, PD-L1, IFNγ, IFNß, CCL20, CXCL5, CXCL10, IL6, IL8, IL10, MCP1, and TNFα and analyzed by Uniform Manifold Approximation and Projection (UMAP) dimension reduction method and k-means clustering analysis. RESULTS: Interestingly, using UMAP analysis, we found that treatment-induced cytokine changes measured as a ratio between baseline and on-treatment samples correlated significantly to progression-free survival (PFS). For patients treated with nivolumab plus ipilimumab we identified a group of patients with superior PFS that were characterized by significantly higher baseline-to-on-treatment increments of PD-1, PD-L1, IFNγ, IL10, CXCL10, and TNFα compared to patients with worse PFS. Particularly, a high PD-1 increment was a strong individual predictor for superior PFS (HR = 0.13; 95% CI 0.034-0.49; p = 0.0026). In contrast, decreasing levels of IFNγ and IL6 and increasing levels of CXCL5 were associated with superior PFS in the pembrolizumab group, although none of the cytokines were individually predictors for PFS. CONCLUSIONS: In short, our study demonstrates that a high increment of PD-1 is associated with superior PFS in advanced-stage melanoma patients treated with nivolumab plus ipilimumab. In contrast, decreasing levels of IFNγ and IL6, and increasing levels of CXCL5 are associated with response to pembrolizumab. These results suggest that using serial samples to monitor changes in cytokine levels early during treatment is informative for treatment response.

Inflammatory Cytokines and ctDNA Are Biomarkers for Progression in Advanced-Stage Melanoma Patients Receiving Checkpoint Inhibitors.

PURPOSE: Checkpoint inhibitors have significantly improved treatment of metastatic melanoma. However, 40-60% of patients do not respond to therapy, emphasizing the need for better predictive biomarkers for treatment response to immune checkpoint inhibitors. Prorammed death-ligand 1(PD-L1) expression in tumor cells is currently used as a predictive biomarker; however, it lacks specificity. Therefore, it is of utmost importance to identify other novel biomarkers that can predict treatment outcome. EXPERIMENTAL DESIGN: We studied a small cohort of 16 patients with advanced-stage melanoma treated with first-line checkpoint inhibitors. Plasma samples were collected prior to treatment initiation and continuously during the first year of treatment. Circulating tumor DNA (ctDNA) level and the expression of ten inflammatory cytokines were analyzed. RESULTS: We found that the ctDNA-level in a blood sample collected after 6-8 weeks of therapy is predictive for response to checkpoint inhibitors. Patients with undetectable ctDNA had significantly longer progression-free survival (PFS) compared with patients with detectable ctDNA (median 26.3 vs. 2.1 months, p = 0.006). In parallel, we identified that high levels of the cytokines monocyte chemoattractant protein 1 (MCP1) and tumor necrosis factor a(TNFa) in baseline blood samples were significantly associated with longer PFS compared to low level of these cytokines (median not reached vs. 8.2 months p = 0.0008). CONCLUSIONS: These findings suggest that the levels of ctDNA, MCP1, and TNFa in baseline and early follow-up samples can predict disease progression in metastatic melanoma patients treated with checkpoint inhibitors. Potentially, these minimally invasive biomarkers may identify responders from non-responders.

[Immunotherapy for patients with malignant melanoma and brain metastases].

Melanoma has a high propensity to form brain metastases, and in this review, we discuss the treatment options for brain metastases. These have previously been sparse, but with the introduction of targeted therapy and checkpoint inhibitors, studies including patients with brain metastases have been published. Recent studies investigating combination of either dabrafenib and trametinib or ipilimumab and nivolumab have proved promising. Based on phase II studies, the most effective treatment for patients with asymptomatic brain metastases seems to be ipilimumab and nivolumab. Symptomatic brain metastases are presently being further investigated.

The real-world impact of modern treatments on the survival of patients with metastatic melanoma.

Between 2010 and 2015, pivotal trials with strict enrolment criteria led to the approval of several new treatments for metastatic melanoma (MM). We sought to determine the impact of these treatments in the 'real world'. We took advantage of the Danish MM database (DAMMED), which contains data on the entire, unselected population diagnosed with MM within Denmark. All MM cases (excluding ocular MM, n = 837) diagnosed in three non-consecutive years marked by major changes in the first-line treatments (2012: interleukin-2 and BRAF inhibitors; 2014: anti-CTLA-4: Cytotoxic T-Lymphocyte Antigen 4 and 2016: anti-PD-1: programmed cell death protein 1 and MEK inhibitors) were retrieved. Patients were grouped into 'trial-like' and 'trial-excluded' based on the common trial eligibility criteria. In the 'trial-like' population (39% of all MM), the median overall survival (OS) was not reached in 2016 versus 18.8 months in 2014 (hazard ratio [HR] 0.52, 95% confidence interval [CI] 0.35-0.75; p = 0.0005) and 16.5 months in 2012 (HR 0.41, 95% CI 0.27-0.63; p < 0.0001). In the 'trial-excluded' population (61% of all MM), 75% had brain metastases and/or (performance status) PS ≥ 2. Here, the median OS improved to 6.9 months in 2016 versus 5.2 months in 2014 (HR 0.66, 95% CI 0.52-0.84; p = 0.0008) and 4.2 months in 2012 (HR 0.66, 95% CI 0.52-0.84; p = 0.0007). Subgroup analysis of the BRAF wild-type population showed an improved 1-year survival rate in 2016 versus 2014 (35.9% vs 18.8%, p = 0.0153). In conclusion, the introduction of modern treatments has led to an improved survival of real-world patients with MM, regardless of their eligibility to clinical trials and the BRAF status. These data support the application of modern treatments to patient populations which are not represented in pivotal trials.

Bullous Pemphigoid as an Adverse Reaction to Pembrolizumab: Two Case Reports.

Checkpoint inhibitors are novel and promising treatment options for different types of cancer. Programmed cell death 1 (PD-1) inhibitors, such as pembrolizumab, have been shown to significantly raise the survival rates of disseminated malignant melanoma (MM). Autoimmune adverse reactions are very common in checkpoint inhibitors. We present 2 cases of bullous pemphigoid, as adverse reactions to pembrolizumab-treated MM.