Kim Margolin

Pembrolizumab versus investigator-choice chemotherapy for ipilimumab-refractory melanoma (KEYNOTE-002): a randomised, controlled, phase 2 trial

BACKGROUND Patients with melanoma that progresses on ipilimumab and, if BRAF(V600) mutant-positive, a BRAF or MEK inhibitor or both, have few treatment options. We assessed the efficacy and safety of two pembrolizumab doses versus investigator-choice chemotherapy in patients with ipilimumab-refractory melanoma. METHODS We carried out a randomised phase 2 trial of patients aged 18 years or older from 73 hospitals, clinics, and academic medical centres in 12 countries who had confirmed progressive disease within 24 weeks after two or more ipilimumab doses and, if BRAF(V600) mutant-positive, previous treatment with a BRAF or MEK inhibitor or both. Patients had to have resolution of all ipilimumab-related adverse events to grade 0-1 and prednisone 10 mg/day or less for at least 2 weeks, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and at least one measurable lesion to be eligible. Using a centralised interactive voice response system, we randomly assigned (1:1:1) patients in a block size of six to receive intravenous pembrolizumab 2 mg/kg or 10 mg/kg every 3 weeks or investigator-choice chemotherapy (paclitaxel plus carboplatin, paclitaxel, carboplatin, dacarbazine, or oral temozolomide). Randomisation was stratified by ECOG performance status, lactate dehydrogenase concentration, and BRAF(V600) mutation status. Individual treatment assignment between pembrolizumab and chemotherapy was open label, but investigators and patients were masked to assignment of the dose of pembrolizumab. We present the primary endpoint at the prespecified second interim analysis of progression-free survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT01704287. The study is closed to enrolment but continues to follow up and treat patients. FINDINGS Between Nov 30, 2012, and Nov 13, 2013, we enrolled 540 patients: 180 patients were randomly assigned to receive pembrolizumab 2 mg/kg, 181 to receive pembrolizumab 10 mg/kg, and 179 to receive chemotherapy. Based on 410 progression-free survival events, progression-free survival was improved in patients assigned to pembrolizumab 2 mg/kg (HR 0·57, 95% CI 0·45-0·73; p<0·0001) and those assigned to pembrolizumab 10 mg/kg (0·50, 0·39-0·64; p<0·0001) compared with those assigned to chemotherapy. 6-month progression-free survival was 34% (95% CI 27-41) in the pembrolizumab 2 mg/kg group, 38% (31-45) in the 10 mg/kg group, and 16% (10-22) in the chemotherapy group. Treatment-related grade 3-4 adverse events occurred in 20 (11%) patients in the pembrolizumab 2 mg/kg group, 25 (14%) in the pembrolizumab 10 mg/kg group, and 45 (26%) in the chemotherapy group. The most common treatment-related grade 3-4 adverse event in the pembrolizumab groups was fatigue (two [1%] of 178 patients in the 2 mg/kg group and one [<1%] of 179 patients in the 10 mg/kg group, compared with eight [5%] of 171 in the chemotherapy group). Other treatment-related grade 3-4 adverse events include generalised oedema and myalgia (each in two [1%] patients) in those given pembrolizumab 2 mg/kg; hypopituitarism, colitis, diarrhoea, decreased appetite, hyponatremia, and pneumonitis (each in two [1%]) in those given pembrolizumab 10 mg/kg; and anaemia (nine [5%]), fatigue (eight [5%]), neutropenia (six [4%]), and leucopenia (six [4%]) in those assigned to chemotherapy. INTERPRETATION These findings establish pembrolizumab as a new standard of care for the treatment of ipilimumab-refractory melanoma. FUNDING Merck Sharp & Dohme.

Nivolumab for Metastatic Renal Cell Carcinoma: Results of a Randomized Phase II Trial

PURPOSE Nivolumab is a fully human immunoglobulin G4 programmed death-1 immune checkpoint inhibitor antibody that restores T-cell immune activity. This phase II trial assessed the antitumor activity, dose-response relationship, and safety of nivolumab in patients with metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS Patients with clear-cell mRCC previously treated with agents targeting the vascular endothelial growth factor pathway were randomly assigned (blinded ratio of 1:1:1) to nivolumab 0.3, 2, or 10 mg/kg intravenously once every 3 weeks. The primary objective was to evaluate the dose-response relationship as measured by progression-free survival (PFS); secondary end points included objective response rate (ORR), overall survival (OS), and safety. RESULTS A total of 168 patients were randomly assigned to the nivolumab 0.3- (n = 60), 2- (n = 54), and 10-mg/kg (n = 54) cohorts. One hundred eighteen patients (70%) had received more than one prior systemic regimen. Median PFS was 2.7, 4.0, and 4.2 months, respectively (P = .9). Respective ORRs were 20%, 22%, and 20%. Median OS was 18.2 months (80% CI, 16.2 to 24.0 months), 25.5 months (80% CI, 19.8 to 28.8 months), and 24.7 months (80% CI, 15.3 to 26.0 months), respectively. The most common treatment-related adverse event (AE) was fatigue (24%, 22%, and 35%, respectively). Nineteen patients (11%) experienced grade 3 to 4 treatment-related AEs. CONCLUSION Nivolumab demonstrated antitumor activity with a manageable safety profile across the three doses studied in mRCC. No dose-response relationship was detected as measured by PFS. These efficacy and safety results in mRCC support study in the phase III setting.

Antitumor Activity and Biomarker Analysis of Sunitinib in Patients With Bevacizumab-Refractory Metastatic Renal Cell Carcinoma

PURPOSE To assess the safety and efficacy of sunitinib in patients with bevacizumab-refractory metastatic renal cell carcinoma (mRCC) and explore biomarkers for sunitinib response. PATIENTS AND METHODS Patients with mRCC and disease progression after bevacizumab-based therapy received oral sunitinib 50 mg once daily in 6-week cycles on a 4/2 schedule (4 weeks with treatment followed by 2 weeks without treatment) in a phase II multicenter study. The primary end point was objective response rate (ORR). Secondary end points included progression-free survival (PFS), duration of response (DR), overall survival (OS), and safety. Plasma soluble proteins (vascular endothelial growth factor [VEGF]-A, VEGF-C, soluble VEGF receptor [sVEGFR]-3, and placental growth factor [PlGF]) levels were measured. RESULTS Sixty-one patients were enrolled. The ORR was 23.0% (95% CI, 13.2% to 35.5%), median PFS was 30.4 weeks (95% CI, 18.3 to 36.7 weeks), median DR was 44.1 weeks (95% CI, 25.0 to 102.7 weeks), and median OS was 47.1 weeks (95% CI, 36.9 to 79.4 weeks). Mean plasma VEGF-A and PlGF levels significantly increased whereas VEGF-C and sVEGFR-3 levels decreased with sunitinib treatment. Lower baseline levels of sVEGFR-3 and VEGF-C were associated with longer PFS and ORR. Most treatment-related adverse events were of mild-to-moderate intensity and included fatigue, hypertension, and hand-foot syndrome. CONCLUSION Sunitinib has substantial antitumor activity in patients with bevacizumab-refractory mRCC and modulates circulating VEGF pathway biomarkers. These data support the hypothesis that sunitinib inhibits signaling pathways involved in bevacizumab resistance. Baseline levels of sVEGFR-3 and VEGF-C may have potential utility as biomarkers of clinical efficacy in this setting.

PD-1 Blockade with Pembrolizumab in Advanced Merkel-Cell Carcinoma

BACKGROUND Merkel-cell carcinoma is an aggressive skin cancer that is linked to exposure to ultraviolet light and the Merkel-cell polyomavirus (MCPyV). Advanced Merkel-cell carcinoma often responds to chemotherapy, but responses are transient. Blocking the programmed death 1 (PD-1) immune inhibitory pathway is of interest, because these tumors often express PD-L1, and MCPyV-specific T cells express PD-1. METHODS In this multicenter, phase 2, noncontrolled study, we assigned adults with advanced Merkel-cell carcinoma who had received no previous systemic therapy to receive pembrolizumab (anti-PD-1) at a dose of 2 mg per kilogram of body weight every 3 weeks. The primary end point was the objective response rate according to Response Evaluation Criteria in Solid Tumors, version 1.1. Efficacy was correlated with tumor viral status, as assessed by serologic and immunohistochemical testing. RESULTS A total of 26 patients received at least one dose of pembrolizumab. The objective response rate among the 25 patients with at least one evaluation during treatment was 56% (95% confidence interval [CI], 35 to 76); 4 patients had a complete response, and 10 had a partial response. With a median follow-up of 33 weeks (range, 7 to 53), relapses occurred in 2 of the 14 patients who had had a response (14%). The response duration ranged from at least 2.2 months to at least 9.7 months. The rate of progression-free survival at 6 months was 67% (95% CI, 49 to 86). A total of 17 of the 26 patients (65%) had virus-positive tumors. The response rate was 62% among patients with MCPyV-positive tumors (10 of 16 patients) and 44% among those with virus-negative tumors (4 of 9 patients). Drug-related grade 3 or 4 adverse events occurred in 15% of the patients. CONCLUSIONS In this study, first-line therapy with pembrolizumab in patients with advanced Merkel-cell carcinoma was associated with an objective response rate of 56%. Responses were observed in patients with virus-positive tumors and those with virus-negative tumors. (Funded by the National Cancer Institute and Merck; ClinicalTrials.gov number, NCT02267603.).

Randomized phase III trial of treatment with high-dose interleukin-2 either alone or in combination with interferon alfa-2a in patients with advanced melanoma.

PURPOSE To compare the response rate, survival, and toxicity of treatment with high-dose intravenous (IV) bolus interleukin-2 (IL-2) plus interferon alfa-2a (IFN-alpha) with high-dose IL-2 alone in patients with advanced melanoma in a randomized phase III trial design. PATIENTS AND METHODS Eighty-five patients with advanced melanoma were randomly assigned to receive IL-2 6 X 10(6) U/m2 per dose every 8 hours as tolerated for a maximum of 14 doses on days 1 through 5 and 15 through 19, or IL-2 4.5 X 10(6) U/m2 per dose, plus IFN-alpha 3 X 10(6) U/m2 using an identical schedule. A planned interim analysis was performed after 85 patients were entered, which forms the basis for this report. RESULTS Partial response (PR) occurred in two of 44 patients (5%; 95% confidence interval, 1% to 15%) receiving IL-2 alone, compared with four of 41 patients (10%; 95% confidence interval, 3% to 23%) receiving IL-2/IFN-alpha (P = .30). There were no complete responses (CRs). The median duration of response was 11.5 months (range, 2.0 to 15.7+). There was no significant difference in the median survival duration for patients receiving IL-2 alone (10.2 months) compared with patients receiving IL-2/IFN-alpha (9.7 months). The median and mean number of doses of IL-2 were equivalent in both groups, as was toxicity. There were three treatment-related deaths, two in the IL-2-alone arm and one in the IL-2/IFN-alpha arm. The trial was terminated after the first interim analysis based on predefined early-stopping rules, which included termination if the response rate in the IL-2/IFN-alpha arm was less than 25%. CONCLUSION Using the preparation, dose, and schedule of IL-2 in our trial, IFN-alpha failed to enhance significantly the response rate to high-dose IL-2 in the treatment of patients with advanced melanoma.

Response assessment criteria for brain metastases: proposal from the RANO group

CNS metastases are the most common cause of malignant brain tumours in adults. Historically, patients with brain metastases have been excluded from most clinical trials, but their inclusion is now becoming more common. The medical literature is difficult to interpret because of substantial variation in the response and progression criteria used across clinical trials. The Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) working group is an international, multidisciplinary effort to develop standard response and progression criteria for use in clinical trials of treatment for brain metastases. Previous efforts have focused on aspects of trial design, such as patient population, variations in existing response and progression criteria, and challenges when incorporating neurological, neuro-cognitive, and quality-of-life endpoints into trials of patients with brain metastases. Here, we present our recommendations for standard response and progression criteria for the assessment of brain metastases in clinical trials. The proposed criteria will hopefully facilitate the development of novel approaches to this difficult problem by providing more uniformity in the assessment of CNS metastases across trials.

Cytokines in Cancer Immunotherapy

Cytokines are molecular messengers that allow the cells of the immune system to communicate with one another to generate a coordinated, robust, but self-limited response to a target antigen. The growing interest over the past two decades in harnessing the immune system to eradicate cancer has been accompanied by heightened efforts to characterize cytokines and exploit their vast signaling networks to develop cancer treatments. The goal of this paper is to review the major cytokines involved in cancer immunotherapy and discuss their basic biology and clinical applications. The paper will also describe new cytokines in pre-clinical development, combinations of biological agents, novel delivery mechanisms, and potential directions for future investigation using cytokines.

Multiinstitutional phase II trial of intensive combination chemoimmunotherapy for metastatic melanoma.

PURPOSE To evaluate the activity and toxicity of combined high-dose cisplatin, dacarbazine (DTIC), and tamoxifen chemotherapy and high-dose bolus interleukin-2 (IL-2) in patients with metastatic melanoma. PATIENTS AND METHODS Patients with metastatic melanoma, Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and normal organ function were enrolled onto this multiinstitutional Cytokine Working Group trial. Patients received intensive chemoimmunotherapy consisting of cisplatin (50 mg/m2) and DTIC (350 mg/m2) intravenously (IV) on days 1 to 3 and 43 to 45, IL-2 600,000 IU/kg IV every 8 hours on days 12 to 16 and 26 to 30 (maximum, 28 doses), and tamoxifen 20 mg orally each day. Patients were evaluated for response at day 63 of each cycle, and responding patients were given a second cycle of therapy beginning on day 71 to 85. RESULTS Thirty-eight patients were entered onto this study. Toxicities were as expected for the chemotherapy and immunotherapy components of this regimen. Overlapping toxicity consisted primarily of thrombocytopenia (76% of patients required platelet transfusions), neutropenia, anemia, fatigue, and weight loss. Despite these cytopenias, bleeding and infectious complications were rare. There were no treatment-related deaths. Three patients achieved a complete response (CR; 8%), and 13 achieved a partial response (PR). The overall objective response rate was 42% (95% confidence interval [CI], 26% to 58%). Six additional patients had greater than 50% tumor reduction at day 63, which did not persist until a subsequent evaluation. The median duration of response was 5 months (range, 2 to 20+), and the median survival duration was 11 months. CONCLUSION This intensive treatment regimen appears to possess activity in metastatic melanoma comparable, but not superior, to that of other less intensive cisplatin- and IL-2-based chemoimmunotherapy regimens. Although the toxicity and complexity of this regimen make it unsuitable for phase III testing and impractical for more widespread use, the results of this study support a potential favorable interaction between IL-2 and chemotherapy in this disease and highlight the need for appropriately designed phase III trials.

Randomized, Placebo-Controlled, Phase III Trial of Yeast-Derived Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) Versus Peptide Vaccination Versus GM-CSF Plus Peptide Vaccination Versus Placebo in Patients With No Evidence of Disease After Complete Surgical Resection of Locally Advanced and/or Stage IV Melanoma: A Trial of the Eastern Cooperative Oncology Group–American College of Radiology Imaging Network Cancer Research Group (E4697)

PURPOSE We conducted a double-blind, placebo-controlled trial to evaluate the effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) and peptide vaccination (PV) on relapse-free survival (RFS) and overall survival (OS) in patients with resected high-risk melanoma. PATIENTS AND METHODS Patients with completely resected stage IV or high-risk stage III melanoma were grouped by human leukocyte antigen (HLA) -A2 status. HLA-A2-positive patients were randomly assigned to receive GM-CSF, PV, both, or placebo; HLA-A2-negative patients, GM-CSF or placebo. Treatment lasted for 1 year or until recurrence. Efficacy analyses were conducted in the intent-to-treat population. RESULTS A total of 815 patients were enrolled. There were no significant improvements in OS (stratified log-rank P = .528; hazard ratio, 0.94; 95% repeated CI, 0.77 to 1.15) or RFS (P = .131; hazard ratio, 0.88; 95% CI, 0.74 to 1.04) in the patients assigned to GM-CSF (n = 408) versus those assigned to placebo (n = 407). The median OS times with GM-CSF versus placebo treatments were 69.6 months (95% CI, 53.4 to 83.5 months) versus 59.3 months (95% CI, 44.4 to 77.3 months); the 5-year OS probability rates were 52.3% (95% CI, 47.3% to 57.1%) versus 49.4% (95% CI, 44.3% to 54.3%), respectively. The median RFS times with GM-CSF versus placebo were 11.4 months (95% CI, 9.4 to 14.8 months) versus 8.8 months (95% CI, 7.5 to 11.2 months); the 5-year RFS probability rates were 31.2% (95% CI, 26.7% to 35.9%) versus 27.0% (95% CI, 22.7% to 31.5%), respectively. Exploratory analyses showed a trend toward improved OS in GM-CSF-treated patients with resected visceral metastases. When survival in HLA-A2-positive patients who received PV versus placebo was compared, RFS and OS were not significantly different. Treatment-related grade 3 or greater adverse events were similar between GM-CSF and placebo groups. CONCLUSION Neither adjuvant GM-CSF nor PV significantly improved RFS or OS in patients with high-risk resected melanoma. Exploratory analyses suggest that GM-CSF may be beneficial in patients with resected visceral metastases; this observation requires prospective validation.

A single-arm, open-label, expanded access study of vemurafenib in patients with metastatic melanoma in the United States

PurposeThis open-label, multicenter study was designed to allow access to vemurafenib for patients with metastatic melanoma, bridging the time between end of enrollment in the phase III registration trial (December 2010) and commercial availability following US Food and Drug Administration approval of vemurafenib for the treatment of unresectable or metastatic BRAFV600-mutated melanoma (August 2011). Patients and MethodsEligible patients had metastatic melanoma with a BRAFV600 mutation (detected by the cobas 4800 BRAF V600 Mutation Test). Unlike previous vemurafenib trials, patients with poor performance status (PS) and treated brain metastases were permitted. Enrolled patients received oral vemurafenib 960 mg twice daily. ResultsOf 374 patients enrolled at 29 US sites (December 2010 to October 2011), 371 patients received vemurafenib and were followed up for a median of 2.8 months (the study had a prespecified end upon vemurafenib approval and commercial availability). At baseline, most patients (75%) had stage M1c disease, and 19% had an Eastern Cooperative Oncology Group PS of 2 or 3; 72% of patients had received prior systemic therapy for metastatic melanoma, 27% received prior ipilimumab, and 29% radiotherapy for prior brain metastases. Because reassessment data to confirm response were not available for most patients, point estimates of objective response rate (ORR) are reported. Among 241 efficacy-evaluable patients, the ORR was 54% (median time to response, 1.9 months). The ORR in non–central nervous system sites in patients with previously treated brain metastases (n = 68) was 53%. The ORR in prior ipilimumab-treated patients (n = 68) was 52%. For patients with PS of 0 or 1 (n = 210) and 2 or 3 (n = 31), the ORRs were 55%, and 42%, respectively. The safety profile observed was consistent with that reported in previous studies. The number of patients with grade 3 or 4 treatment-related adverse events was higher in patients with PS 2 or 3 than in those with PS 0 or 1 (10% vs. 5%, respectively). Adverse events requiring a dose reduction (at least 1 level) occurred in 11% of patients, and 9 patients (2%) experienced events leading to vemurafenib withdrawal, including 2 with repeated QT interval prolongation. DiscussionThis study confirmed the established rapid and high tumor response rate achievable with vemurafenib in BRAFV600 mutation–positive metastatic melanoma. Several groups not included in previous studies, including patients with previously treated brain metastases, Eastern Cooperative Oncology Group PS 2 to 3, or previous ipilimumab treatment had benefitted from vemurafenib similar to the overall population. No new safety signals were detected.