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Background: Previous studies combining PD-1 checkpoint inhibitors with tyrosine kinase inhibitors of the VEGF pathway have been characterised by excess toxicity, precluding further development. We hypothesised that axitinib, a more selective VEGF inhibitor than others previously tested, could be combined safely with pembrolizumab (anti-PD-1) and yield antitumour activity in patients with treatment-naive advanced renal cell carcinoma.Methods: In this ongoing, open-label, phase 1b study, which was done at ten centres in the USA, we enrolled patients aged 18 years or older who had advanced renal cell carcinoma (predominantly clear cell subtype) with their primary tumour resected, and at least one measureable lesion, Eastern Cooperative Oncology Group performance status 0-1, controlled hypertension, and no previous systemic therapy for renal cell carcinoma. Eligible patients received axitinib plus pembrolizumab in a dose-finding phase to estimate the maximum tolerated dose, and additional patients were enrolled into a dose-expansion phase to further establish safety and determine preliminary efficacy. Axitinib 5 mg was administered orally twice per day with pembrolizumab 2 mg/kg given intravenously every 3 weeks. We assessed safety in all patients who received at least one dose of axitinib or pembrolizumab; antitumour activity was assessed in all patients who received study treatment and had an adequate baseline tumour assessment. The primary endpoint was investigator-assessed dose-limiting toxicity during the first two cycles (6 weeks) to estimate the maximum tolerated dose and recommended phase 2 dose. This study is registered with ClinicalTrials.gov, number NCT02133742.Findings: Between Sept 23, 2014, and March 25, 2015, we enrolled 11 patients with previously untreated advanced renal cell carcinoma to the dose-finding phase and between June 3, 2015, and Oct 13, 2015, we enrolled 41 patients to the dose-expansion phase. All 52 patients were analysed together. No unexpected toxicities were observed. Three dose-limiting toxicities were reported in the 11 patients treated during the 6-week observation period (dose-finding phase): one patient had a transient ischaemic attack and two patients were only able to complete less than 75% of the planned axitinib dose because of treatment-related toxicity. At the data cutoff date (March 31, 2017), 25 (48%) patients were still receiving study treatment. Grade 3 or worse treatment-related adverse events occurred in 34 (65%) patients; the most common included hypertension (n=12 [23%]), diarrhoea (n=5 [10%]), fatigue (n=5 [10%]), and increased alanine aminotransferase concentration (n=4 [8%]). The most common potentially immune-related adverse events (probably related to pembrolizumab) included diarrhoea (n=15 [29%]), increased alanine aminotransferase concentration (n=9 [17%]) or aspartate aminotransferase concentration (n=7 [13%]), hypothyroidism (n=7 [13%]), and fatigue (n=6 [12%]). 28 (54%) patients had treatment-related serious adverse events. At data cutoff, 38 (73%; 95% CI 59·0-84·4) patients achieved an objective response (complete or partial response).Interpretation: The treatment combination of axitinib plus pembrolizumab is tolerable and shows promising antitumour activity in patients with treatment-naive advanced renal cell carcinoma. Whether or not the combination works better than a sequence of VEGF pathway inhibition followed by an anti-PD-1 therapy awaits the completion of a phase 3 trial comparing axitinib plus pembrolizumab with sunitinib monotherapy (NCT02853331).Funding: Pfizer Inc. [ABSTRACT FROM AUTHOR]

Purpose: We performed a phase 1 study to determine the maximum tolerable dose and safety of ipilimumab with stereotactic radiosurgery (SRS) or whole brain radiation therapy (WBRT) in patients with brain metastases from melanoma.Methods and Materials: Based on the intracranial disease burden, patients underwent WBRT (arm A) or SRS (arm B). The ipilimumab starting dose was 3 mg/kg every 3 weeks, starting on day 3 of WBRT or 2 days after SRS. The ipilimumab dose was escalated to 10 mg/kg using a 2-stage, 3+3 design. The primary endpoint was to determine the maximum tolerable dose of ipilimumab combined with radiation therapy. The secondary endpoints were overall survival, intracranial and extracranial control, progression-free survival, and toxicity. The ClinicalTrials.gov registration number is NCT01703507.Results: The characteristics of the 16 patients enrolled between 2011 and 2014 were mean age, 60 years; median number of brain metastases, 2 (range 1->10); and number with EC disease, 13 (81%). Treatment included WBRT (n=5), SRS (n=11), and ipilimumab 3 mg/kg (n=7) or 10 mg/kg (n=9). The median follow-up was 8 months (arm A) and 10.5 months (arm B). A total of 21 grade 1 to 2 neurotoxic effects occurred, with no dose-limiting toxicities. One patient experienced grade 3 neurotoxicity before ipilimumab administration. Ten additional grade 3 toxicities were reported, with gastrointestinal toxicities (n=5; 31%) the most common. No patient developed grade 4 or 5 toxicity. The median progression-free survival and overall survival in arm A was 2.5 months and 8 months and in arm B was 2.1 months and not reached, respectively.Conclusions: Concurrent ipilimumab 10 mg/kg with SRS is safe. The WBRT arm was closed early because of slow accrual but demonstrated safety with ipilimumab 3 mg/kg. No patient experienced dose-limiting toxicity. Larger studies, including those with combination checkpoint inhibitor therapy and SRS, are warranted. [ABSTRACT FROM AUTHOR]

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.). [ABSTRACT FROM AUTHOR]