Nivolumab improved survival vs dacarbazine in patients with untreated advanced melanoma

Immune checkpoint: The novel target for antitumor therapy

Inhibitory checkpoint molecules include programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), cytotoxic T lymphocyte antigen-4 (CTLA-4), human endogenous retrovirus-H Long terminal repeat-associating 2 (HHLA2), B7 homolog 4 protein (B7-H4), T cell membrane protein-3 (TIM-3) and Lymphocyte-activation gene 3 (LAG-3), which are up-regulated during tumorigenesis. These pathways are essential to down-regulate the immune system by blocking the activation of T cells. In recent years, immune checkpoint blockers (ICBs) against PD-1, PD-L1, CTLA-4 or TIM-3 has made remarkable progress in the clinical application, revolutionizing the treatment of malignant tumors and improving patients' overall survival. However, the efficacy of ICBs in some patients does not seem to be good enough, and more immune-related adverse events (irAEs) will inevitably occur. Therefore, biomarkers research provides practical guidance for clinicians to identify patients who are most likely to benefit from or exhibit resistance to particular types of immune checkpoint therapy. There are two points in general. On the one hand, given the spatial and temporal differential expression of immune checkpoint molecules during immunosuppression process, it is essential to understand their mechanisms to design the most effective individualized therapy. On the other hand, due to the lack of potent immune checkpoints, it is necessary to combine them with novel biomarkers (such as exosomes and ctDNA) and other anticancer modalities (such as chemotherapy and radiotherapy).

Prognostic significance of mast cell and microvascular densities in malignant peripheral nerve sheath tumor with and without neurofibromatosis type 1

Malignant peripheral nerve sheath tumors (MPNSTs) are rare and aggressive soft tissue sarcomas with a significant susceptibility to metastasize early in their course. Pathogenesis is yet to be fully elucidated. Recently, the essential role of mast cells in the tumor onset of neurofibromatosis type 1 (NF1)‐associated neurofibromas and MPNSTs was confirmed in both experimental and human studies. In this study, we investigate mast cell density (MCD), microvascular density (MVD), and proliferation index (Ki‐67) in MPNST. A secondary aim was to correlate histological staining to clinical data and survival in patients with and without NF1. In total, 34 formalin‐fixed paraffin‐embedded MPNST tissues from 29 patients were eligible. MCD, MVD, and Ki‐67 labeling index (LI) were analyzed in all stained tissues by a computer‐based quantitative algorithm (Aperio ImageScope). In addition, chart review was performed for clinical data and survival analysis. Overall, MCD, MVD, and Ki‐67 LI were evenly distributed throughout tumor tissue. There was a negative correlation of NF1 status (affected, P = 0.037), tumor size (>10 cm, P = 0.023), and MVD in the tumor periphery (higher tercile, P = 0.002) to survival. Multivariate analysis confirmed the association of MVD in the tumor periphery (higher tercile, P = 0.019) with a decreased overall survival. Diverse mast cell and microvascular distributions suggest that angiogenesis in MPNST occurs independently. The role of mast cells in tumor progression is unclear and lacks prognostic value. Higher MVD has prognostic significance with possible therapeutic implications in MPNST.

Circulating tumor DNA to monitor treatment response and detect acquired resistance in patients with metastatic melanoma

Repeat tumor biopsies to study genomic changes during therapy are difficult, invasive and data are confounded by tumoral heterogeneity. The analysis of circulating tumor DNA (ctDNA) can provide a non-invasive approach to assess prognosis and the genetic evolution of tumors in response to therapy. Mutation-specific droplet digital PCR was used to measure plasma concentrations of oncogenic BRAF and NRAS variants in 48 patients with advanced metastatic melanoma prior to treatment with targeted therapies (vemurafenib, dabrafenib or dabrafenib/trametinib combination) or immunotherapies (ipilimumab, nivolumab or pembrolizumab). Baseline ctDNA levels were evaluated relative to treatment response and progression-free survival (PFS). Tumor-associated ctDNA was detected in the plasma of 35/48 (73%) patients prior to treatment and lower ctDNA levels at this time point were significantly associated with response to treatment and prolonged PFS, irrespective of therapy type. Levels of ctDNA decreased significantly in patients treated with MAPK inhibitors (p < 0.001) in accordance with response to therapy, but this was not apparent in patients receiving immunotherapies. We show that circulating NRAS mutations, known to confer resistance to BRAF inhibitors, were detected in 3 of 7 (43%) patients progressing on kinase inhibitor therapy. Significantly, ctDNA rebound and circulating mutant NRAS preceded radiological detection of progressive disease. Our data demonstrate that ctDNA is a useful biomarker of response to kinase inhibitor therapy and can be used to monitor tumor evolution and detect the early appearance of resistance effectors.

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ANTI-PD1 ROLE IN TREATMENT OF CUTANEOUS MELANOMA: The treatment of metastatic melanoma dramatically changed over the last years. Two therapeutic revolutions emerged in parallel, targeted anti-BRAF and anti-MEK therapies, for patients BRAFV600 mutated and immunotherapy with immune checkpoint blockers using anti-CTLA-4 then anti-PD1 monoclonal antibodies. Indeed, melanoma immunotherapy was a golden objective for many years but in spite of important efforts using cytokines (interferon, interleukin) and different vaccine approaches no objective improvement of patients 'prognosis was obtained. Ipilimumab, authorized in 2011, was the first drug which showed a benefit of overall survival in patients with metastatic melanoma in spite a low response rate (10-15) and the occurrence of about 25% of serious toxicity. Anti-PD1 appear as a new generation of immune checkpoint blockade with response rates between 30 to 40% of the patients, a proven overall survival benefit as compared with chemotherapy or ipilimumab and less toxicity than ipilimumab. Two molecules, pembrolizumab and nivolumab were recently approved in monotherapy, for metastatic melanoma. Several questions remain unresolved: the respective indications of anti-PD1 and targeted therapies in first line therapy in patients with BRAF mutant melanoma, the benefit of combining immunotherapy with radiotherapy or with targeted therapies, the optimal treatment duration, and the benefit of the anti-PD1 in the adjuvant setting. The combination of ipilimumab and nivolumab, recently approved by the FDA but not yet in Europ, shows an improvement of the objective response rates (50-57%) and progression free survival compared with nivolumab but is associated with an higer incidence of serious adverse events (more than 50%).

Evaluation of the potential for QTc prolongation in patients with solid tumors receiving nivolumab

PURPOSE

The fully human monoclonal antibody nivolumab binds to the programmed death-1 (PD-1) receptor, blocking interactions between PD-1 and its ligands on tumor cells and preventing T cell exhaustion in patients with cancer. The potential for corrected QT interval (QTc) prolongation was assessed in a subset of patients enrolled in a phase 2 dose-ranging study of nivolumab.

METHODS

Triplicate 12-lead electrocardiograms (ECGs) obtained predose and post-dose were assessed by an independent ECG core laboratory. QTc derived from Fridericia's formula (QTcF) was evaluated by central tendency, categorical, and concentration-response analyses.

RESULTS

No patients had QTcF intervals or changes from baseline in QTcF (ΔQTcF) exceeding prespecified thresholds indicating borderline or prolonged QTcF (>480 ms) or ΔQTcF (>60 ms). Among 146 patients randomized to nivolumab 0.3, 2.0, or 10.0 mg/kg every 3 weeks, the maximum increases in mean (± SD) ∆QTcF at any time point were 4.9 (± 13.4), 1.2 (± 10.1), and 2.0 (± 8.9) ms, respectively. There was no relationship between ∆QTcF and nivolumab serum concentration and no association between predicted maximum ∆QTcF and mean maximum nivolumab concentration in any dosage group.

CONCLUSION

Results of these intensive ECG analyses indicate that nivolumab has no clinically meaningful effect on QTc interval when administered at doses up to 10.0 mg/kg.

Nanotechnology-based strategies for combating toxicity and resistance in melanoma therapy

Drug toxicity and resistance remain formidable challenges in cancer treatment and represent an area of increasing attention in the case of melanoma. Nanotechnology represents a paradigm-shifting field with the potential to mitigate drug resistance while improving drug delivery and minimizing toxicity. Recent clinical and pre-clinical studies have demonstrated how a diverse array of nanoparticles may be harnessed to circumvent known mechanisms of drug resistance in melanoma to improve therapeutic efficacy. In this review, we discuss known mechanisms of resistance to various melanoma therapies and possible nanotechnology-based strategies that could be used to overcome these barriers and improve the pharmacologic arsenal available to combat advanced stage melanoma.

Nivolumab in Resected and Unresectable Metastatic Melanoma: Characteristics of Immune-Related Adverse Events and Association with Outcomes

PURPOSE

Retrospective analysis of irAEs in melanoma patients treated with nivolumab.

EXPERIMENTAL DESIGN

Data were pooled from 148 patients (33 resected, 115 unresectable) treated with nivolumab plus peptide vaccine or nivolumab alone every 2 weeks for 12 weeks. Patients with stable disease or regression received an additional 12-week cycle, then nivolumab alone every 12 weeks for up to 2 additional years. Frequency, grade, and characteristics of immune-related adverse events (irAE) were analyzed. A 12-week landmark survival analysis using a multivariate time-dependent Cox proportional hazard model assessed difference in overall survival (OS) in the presence or absence of irAEs.

RESULTS

IrAEs of any grade were observed in 68.2% of patients (101 of 148). Grade III/IV irAEs were infrequent: 3 (2%) had grade III rash, 2 (1.35%) had asymptomatic grade III elevation in amylase/lipase, and 2 (1.35%) had grade III colitis. A statistically significant OS difference was noted among patients with any grade of irAE versus those without (P ≤ 0.001), and OS benefit was noted in patients who reported three or more irAE events (P ≤ 0.001). Subset analyses showed statistically significant OS differences with rash [P = 0.001; HR, 0.423; 95% confidence interval (CI), 0.243-0.735] and vitiligo (P = 0.012; HR, 0.184; 95% CI, 0.036-0.94). Rash and vitiligo also correlated with statistically significant OS differences in patients with metastatic disease (P = 0.004 and P = 0.028, respectively). No significant survival differences were seen with other irAEs (endocrinopathies, colitis, or pneumonitis).

CONCLUSIONS

Cutaneous irAEs are associated with improved survival in melanoma patients treated with nivolumab, and clinical benefit should be validated in larger prospective analyses.

Nivolumab and pembrolizumab as immune-modulating monoclonal antibodies targeting the PD-1 receptor to treat melanoma

Malignant melanoma is an important issue in oncology due to its high incidence, high mortality, and resistance to systemic therapy; however, targeted immunotherapy has noticeably improved the survival rates of melanoma patients. Promising targeted immunotherapies for malignant melanoma include the blockade of immune checkpoints with antibodies targeting cytotoxic T lymphocyte-associated antigen 4 and the programmed cell death protein 1 pathway. The US FDA-approved antibody ipilimumab targets cytotoxic T lymphocyte-associated antigen 4; however, it was limited by toxicity and a low response. Nivolumab and pembrolizumab (formerly lambrolizumab), the two FDA-approved anti-programmed death-1 monoclonal antibodies, show highly durable response rates and long-term safety, validating the importance of the programmed cell death protein 1 pathway blockade for treatment of malignant melanoma.