Paola Queirolo

Vaccination of Metastatic Melanoma Patients With Autologous Tumor-Derived Heat Shock Protein gp96-Peptide Complexes: Clinical and Immunologic Findings

PURPOSE To determine the immunogenicity and antitumor activity of a vaccine consisting of autologous, tumor-derived heat shock protein gp96-peptide complexes (HSPPC-96, Oncophage; Antigenics, Inc, Woburn, MA) in metastatic (American Joint Committee on Cancer stage IV) melanoma patients. PATIENTS AND METHODS Sixty-four patients had surgical resection of metastatic tissue required for vaccine production, 42 patients were able to receive the vaccine, and 39 were assessable after one cycle of vaccination (four weekly injections). In 21 patients, a second cycle (four biweekly injections) was given because no progression occurred. Antigen-specific antimelanoma T-cell response was assessed by enzyme-linked immunospot (ELISPOT) assay on peripheral blood mononuclear cells (PBMCs) obtained before and after vaccination. Immunohistochemical analyses of tumor tissues were also performed. RESULTS No treatment-related toxicity was observed. Of 28 patients with measurable disease, two had a complete response (CR) and three had stable disease (SD) at the end of follow-up. Duration of CR was 559+ and 703+ days, whereas SD lasted for 153, 191, and 272 days, respectively. ELISPOT assay with PBMCs of 23 subjects showed a significantly increased number of postvaccination melanoma-specific T-cell spots in 11 patients, with clinical responders displaying a high frequency of increased T-cell activity. Immunohistochemical staining of melanoma tissues from which vaccine was produced revealed high expression of both HLA class I and melanoma antigens in seven of eight clinical responders (two with CR, three with SD, and the three with long-term disease-free survival) and in four of 12 nonresponders. CONCLUSION Vaccination of metastatic melanoma patients with autologous HSPPC-96 is feasible and devoid of significant toxicity. This vaccine induced clinical and tumor-specific T-cell responses in a significant minority of patients.

MEK162 for patients with advanced melanoma harbouring NRAS or Val600 BRAF mutations: a non-randomised, open-label phase 2 study

BACKGROUND Patients with melanoma harbouring Val600 BRAF mutations benefit from treatment with BRAF inhibitors. However, no targeted treatments exist for patients with BRAF wild-type tumours, including those with NRAS mutations. We aimed to assess the use of MEK162, a small-molecule MEK1/2 inhibitor, in patients with NRAS-mutated or Val600 BRAF-mutated advanced melanoma. METHODS In our open-label, non-randomised, phase 2 study, we assigned patients with NRAS-mutated or BRAF-mutated advanced melanoma to one of three treatment arms on the basis of mutation status. Patients were enrolled at university hospitals or private cancer centres in Europe and the USA. The three arms were: twice-daily MEK162 45 mg for NRAS-mutated melanoma, twice-daily MEK162 45 mg for BRAF-mutated melanoma, and twice-daily MEK162 60 mg for BRAF-mutated melanoma. Previous treatment with BRAF inhibitors was permitted, but previous MEK inhibitor therapy was not allowed. The primary endpoint was the proportion of patients who had an objective response (ie, a complete response or confirmed partial response). We report data for the 45 mg groups. We assessed clinical activity in all patients who received at least one dose of MEK162 and in patients assessable for response (with two available CT scans). This study is registered with ClinicalTrials.gov, number NCT01320085, and is currently recruiting additional patients with NRAS mutations (based on a protocol amendment). FINDINGS Between March 31, 2011, and Jan 17, 2012, we enrolled 71 patients who received at least one dose of MEK162 45 mg. By Feb 29, 2012 (data cutoff), median follow-up was 3·3 months (range 0·6-8·7; IQR 2·2-5·0). No patients had a complete response. Six (20%) of 30 patients with NRAS-mutated melanoma had a partial response (three confirmed) as did eight (20%) of 41 patients with BRAF-mutated melanoma (two confirmed). The most frequent adverse events were acneiform dermatitis (18 [60%] patients with NRAS -mutated melanoma and 15 [37%] patients with the BRAF-mutated melanoma), rash (six [20%] and 16 [39%]), peripheral oedema (ten [33%] and 14 [34%]), facial oedema (nine [30%] and seven [17%]), diarrhoea (eight [27%] and 15 [37%]), and creatine phosphokinase increases (11 [37%] and nine [22%]). Increased creatine phosphokinase was the most common grade 3-4 adverse event (seven [23%] and seven [17%]). Four patients had serious adverse events (two per arm), which included diarrhoea, dehydration, acneiform dermatitis, general physical deterioration, irregular heart rate, malaise, and small intestinal perforation. No deaths occurred from treatment-related causes. INTERPRETATION To our knowledge, MEK162 is the first targeted therapy to show activity in patients with NRAS -mutated melanoma and might offer a new option for a cancer with few effective treatments. FUNDING Novartis Pharmaceuticals.

Efficacy and safety of ipilimumab monotherapy in patients with pretreated advanced melanoma: a multicenter single-arm phase II study

BACKGROUND This phase II study evaluated the safety and activity of ipilimumab, a fully human mAb that blocks cytotoxic T-lymphocyte antigen-4, in patients with advanced melanoma. PATIENTS AND METHODS Patients with previously treated, unresectable stage III/stage IV melanoma received 10 mg/kg ipilimumab every 3 weeks for four cycles (induction) followed by maintenance therapy every 3 months. The primary end point was best overall response rate (BORR) using modified World Health Organization (WHO) criteria. We also carried out an exploratory analysis of proposed immune-related response criteria (irRC). RESULTS BORR was 5.8% with a disease control rate (DCR) of 27% (N = 155). One- and 2-year survival rates (95% confidence interval) were 47.2% (39.5% to 55.1%) and 32.8% (25.4% to 40.5%), respectively, with a median overall survival of 10.2 months (7.6-16.3). Of 43 patients with disease progression by modified WHO criteria, 12 had disease control by irRC (8% of all treated patients), resulting in a total DCR of 35%. Adverse events (AEs) were largely immune related, occurring mainly in the skin and gastrointestinal tract, with 19% grade 3 and 3.2% grade 4. Immune-related AEs were manageable and generally reversible with corticosteroids. CONCLUSION Ipilimumab demonstrated clinical activity with encouraging long-term survival in a previously treated advanced melanoma population.

Ipilimumab and fotemustine in patients with advanced melanoma (NIBIT-M1): an open-label, single-arm phase 2 trial

BACKGROUND Ipilimumab improves survival of patients with metastatic melanoma, many of whom develop brain metastases. Chemotherapy-induced release of tumour antigens might amplify ipilimumabs antitumour activity. We aimed to investigate the efficacy and safety of ipilimumab plus fotemustine in patients with metastatic melanoma with or without asymptomatic brain metastases. METHODS In our open-label, single-arm phase 2 trial, we enrolled patients 18 years or older with measurable, locally advanced, unresectable stage III or stage IV melanoma between July 6, 2010, and April 14, 2011. Eligible patients had a life expectancy of 16 weeks or more and an Eastern Cooperative Oncology Group performance status of 1 or less, and could have received a maximum of one previous line of chemotherapy. Participants received induction treatment of 10 mg/kg intravenous ipilimumab every 3 weeks to a total of four doses, and 100 mg/m(2) intravenous fotemustine weekly for 3 weeks and then every 3 weeks from week 9 to week 24. Patients with a confirmed clinical response were eligible for maintenance treatment from week 24, with ipilimumab every 12 weeks and fotemustine every 3 weeks. The primary endpoint was the proportion of patients with immune-related disease control as established with immune-related response criteria. Analyses were done per protocol. This trial is registered with EudraCT, number 2010-019356-50, and with ClinicalTrials.gov, number NCT01654692. FINDINGS 86 patients were eligible for treatment, of whom 20 had asymptomatic brain metastases at baseline. 40 patients in the study population achieved disease control (46·5%, 95% CI 35·7-57·6), as did ten with brain metastases (50·0%, 27·2-72·8). 47 patients (55%) had grade 3 or 4 treatment-related adverse events, of which the most common was myelotoxicity (thrombocytopenia in 21 [24%] patients and neutropenia in 16 [19%]). The most common grade 3 or 4 immune-related adverse events were hepatic: 21 patients (24%) had grade 3 or 4 increases in concentrations of alanine aminotransferase or aspartate aminotransferase. INTERPRETATION The combination of ipilimumab plus fotemustine has clinical activity in patients with metastatic melanoma, including those with brain metastases. FUNDING Bristol-Myers Squibb.

Melanoma Cells Inhibit Natural Killer Cell Function by Modulating the Expression of Activating Receptors and Cytolytic Activity

Natural killer (NK) cells play a key role in tumor immune surveillance. However, adoptive immunotherapy protocols using NK cells have shown limited clinical efficacy to date, possibly due to tumor escape mechanisms that inhibit NK cell function. In this study, we analyzed the effect of coculturing melanoma cells and NK cells on their phenotype and function. We found that melanoma cells inhibited the expression of major NK receptors that trigger their immune function, including NKp30, NKp44, and NKG2D, with consequent impairment of NK cell-mediated cytolytic activity against various melanoma cell lines. This inhibitory effect was primarily mediated by indoleamine 2,3-dioxygenase (IDO) and prostaglandin E2 (PGE2). Together, our findings suggest that immunosuppressive barriers erected by tumors greatly hamper the antitumor activity of human NK cells, thereby favoring tumor outgrowth and progression.

Adjuvant Nivolumab versus Ipilimumab in Resected Stage III or IV Melanoma

BACKGROUND Nivolumab and ipilimumab are immune checkpoint inhibitors that have been approved for the treatment of advanced melanoma. In the United States, ipilimumab has also been approved as adjuvant therapy for melanoma on the basis of recurrence‐free and overall survival rates that were higher than those with placebo in a phase 3 trial. We wanted to determine the efficacy of nivolumab versus ipilimumab for adjuvant therapy in patients with resected advanced melanoma. METHODS In this randomized, double‐blind, phase 3 trial, we randomly assigned 906 patients (≥15 years of age) who were undergoing complete resection of stage IIIB, IIIC, or IV melanoma to receive an intravenous infusion of either nivolumab at a dose of 3 mg per kilogram of body weight every 2 weeks (453 patients) or ipilimumab at a dose of 10 mg per kilogram every 3 weeks for four doses and then every 12 weeks (453 patients). The patients were treated for a period of up to 1 year or until disease recurrence, a report of unacceptable toxic effects, or withdrawal of consent. The primary end point was recurrence‐free survival in the intention‐to‐treat population. RESULTS At a minimum follow‐up of 18 months, the 12‐month rate of recurrence‐free survival was 70.5% (95% confidence interval [CI], 66.1 to 74.5) in the nivolumab group and 60.8% (95% CI, 56.0 to 65.2) in the ipilimumab group (hazard ratio for disease recurrence or death, 0.65; 97.56% CI, 0.51 to 0.83; P<0.001). Treatment‐related grade 3 or 4 adverse events were reported in 14.4% of the patients in the nivolumab group and in 45.9% of those in the ipilimumab group; treatment was discontinued because of any adverse event in 9.7% and 42.6% of the patients, respectively. Two deaths (0.4%) related to toxic effects were reported in the ipilimumab group more than 100 days after treatment. CONCLUSIONS Among patients undergoing resection of stage IIIB, IIIC, or IV melanoma, adjuvant therapy with nivolumab resulted in significantly longer recurrence‐free survival and a lower rate of grade 3 or 4 adverse events than adjuvant therapy with ipilimumab. (Funded by Bristol‐Myers Squibb and Ono Pharmaceutical; CheckMate 238 ClinicalTrials.gov number, NCT02388906; Eudra‐CT number, 2014‐002351‐26.)

Vemurafenib in patients with BRAFV600 mutated metastatic melanoma: an open-label, multicentre, safety study

BACKGROUND The orally available BRAF kinase inhibitor vemurafenib, compared with dacarbazine, shows improved response rates, progression-free survival (PFS), and overall survival in patients with metastatic melanoma that has a BRAF(V600) mutation. We assessed vemurafenib in patients with advanced metastatic melanoma with BRAF(V600) mutations who had few treatment options. METHODS In an open-label, multicentre study, patients with untreated or previously treated melanoma and a BRAF(V600) mutation received oral vemurafenib 960 mg twice a day. The primary endpoint was safety. All analyses were done on the safety population, which included all patients who received at least one dose of vemurafenib. This report is the third interim analysis of this study. This study is registered with ClinicalTrials.gov, number NCT01307397. FINDINGS Between March 1, 2011, and Jan 31, 2013, 3226 patients were enrolled in 44 countries. 3222 patients received at least one dose of vemurafenib (safety population). At data cutoff, 868 (27%) patients were on study treatment and 2354 (73%) had withdrawn, mainly because of disease progression. Common adverse events of all grades included rash (1592 [49%]), arthralgia (1259 [39%]), fatigue (1093 [34%]), photosensitivity reaction (994 [31%]), alopecia (826 [26%]), and nausea (628 [19%]). 1480 (46%) patients reported grade 3 or 4 adverse events, including cutaneous squamous cell carcinoma (389 [12%]), rash (155 [5%]), liver function abnormalities (165 [5%]), arthralgia (106 [3%]), and fatigue (93 [3%]). Grade 3 and 4 adverse events were reported more frequently in patients aged 75 years and older (n=257; 152 [59%, 95% CI 53-65] and ten [4%, 2-7], respectively) than in those younger than 75 years (n=2965; 1286 [43%, 42-45] and 82 [3%, 2-3], respectively). INTERPRETATION Vemurafenib safety in this diverse population of patients with BRAF(V600) mutated metastatic melanoma, who are more representative of routine clinical practice, was consistent with the safety profile shown in the pivotal trials of this drug. FUNDING F Hoffmann-La Roche.

Rare missense variants in POT1 predispose to familial cutaneous malignant melanoma

Although CDKN2A is the most frequent high-risk melanoma susceptibility gene, the underlying genetic factors for most melanoma-prone families remain unknown. Using whole-exome sequencing, we identified a rare variant that arose as a founder mutation in the telomere shelterin gene POT1 (chromosome 7, g.124493086C>T; p.Ser270Asn) in five unrelated melanoma-prone families from Romagna, Italy. Carriers of this variant had increased telomere lengths and numbers of fragile telomeres, suggesting that this variant perturbs telomere maintenance. Two additional rare POT1 variants were identified in all cases sequenced in two separate Italian families, one variant per family, yielding a frequency for POT1 variants comparable to that for CDKN2A mutations in this population. These variants were not found in public databases or in 2,038 genotyped Italian controls. We also identified two rare recurrent POT1 variants in US and French familial melanoma cases. Our findings suggest that POT1 is a major susceptibility gene for familial melanoma in several populations.

Melanoma-associated fibroblasts modulate NK cell phenotype and antitumor cytotoxicity

Although the role of the tumor microenvironment in the process of cancer progression has been extensively investigated, the contribution of different stromal components to tumor growth and/or evasion from immune surveillance is still only partially defined. In this study we analyzed fibroblasts derived from metastatic melanomas and provide evidence for their strong immunosuppressive activity. In coculture experiments, melanoma-derived fibroblasts sharply interfered with NK cell functions including cytotoxicity and cytokine production. Thus, both the IL-2-induced up-regulation of the surface expression of NKp44, NKp30, and DNAM-1 triggering receptors and the acquisition of cytolytic granules were inhibited in NK cells. This resulted in an impairment of the NK cell-mediated killing of melanoma target cells. Transwell cocultures and the use of specific inhibitors suggested that cell-to-cell contact was required for inducing DNAM-1 modulation. In contrast, modulation of NKp44 and NKp30 was due to PGE2 released by fibroblasts during coculture. Normal skin fibroblasts could also partially affect NK cell phenotype and function. However, the inhibitory effect of tumor-derived fibroblasts was far stronger and directly correlated with their ability to produce PGE2 either constitutively or upon induction by NK cells.

Natural killer cells kill human melanoma cells with characteristics of cancer stem cells

Experimental and clinical data suggest that tumours harbour a cell population retaining stem cell characteristics that can drive tumorigenesis. CD133 is considered an important cancer stem cells (CSC)-associated marker. In a large variety of human malignancies, including melanoma, CD133(+) cells have been reported to comprise CSC. In this study, we show that melanoma cell lines are highly heterogeneous for the expression of several stem cell-associated markers including CD133, c-kit/CD117 and p75 neurotrophin receptor/CD271. Since no information is available on the ability of NK cells to recognize and lyse melanoma stem cells, we assessed whether melanoma cell lines, characterized by stem cell-like features, were susceptible to lysis by IL-2-activated NK cells. We show that activated NK cells efficiently kill malignant melanoma cell lines that were enriched in putative CSC by the use of different selection methods (i.e. CD133 expression, radioresistance or the ability to form melanospheres in stem cell-supportive medium). NK cell-mediated recognition and lysis of melanoma cells involved different combinations of activating NK receptors. Since CSC have been reported to be both drug resistant and radioresistant, our present data suggest that NK-based adoptive immunotherapy could represent a novel therapeutic approach to possibly eradicate metastatic melanoma.