***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: PURPOSE Programmed death-1 ( PD-1 ) , an inhibitory receptor expressed on activated T cells , may suppress antitumor immunity . This phase I study sought to determine the safety and tolerability of anti-PD-1 blockade in patients with treatment-refractory solid tumors and to preliminarily assess antitumor activity , pharmacodynamics , and immunologic correlates . PATIENTS AND METHODS Thirty-nine patients with advanced metastatic melanoma , colorectal cancer ( CRC ) , castrate-resistant prostate cancer , non-small-cell lung cancer ( NSCLC ) , or renal cell carcinoma ( RCC ) received a single intravenous infusion of  anti-PD-1 ( MDX-1106 ) in dose-escalating six-patient cohorts at 0.3 , 1 , 3 , or 10 mg/kg , followed by a 15-patient expansion cohort at 10 mg/kg . Patients with evidence of clinical benefit at 3 months were eligible for repeated therapy . RESULTS Anti-PD-1 was well tolerated : one serious adverse event , inflammatory colitis , was observed in a patient with melanoma who received five doses at 1 mg/kg . One durable complete response ( CRC ) and two partial responses ( PRs ; melanoma , RCC ) were seen . Two additional patients ( melanoma , NSCLC ) had significant lesional tumor regressions not meeting PR criteria . The serum half-life of anti-PD-1 was 12 to 20 days . However , pharmacodynamics indicated a sustained mean occupancy of > 70 % of PD-1 molecules on circulating T cells > or = 2 months following infusion , regardless of dose . In nine patients examined , tumor cell surface B7-H1 expression appeared to correlate with the likelihood of response to treatment . CONCLUSION Blocking the PD-1 immune checkpoint with intermittent antibody dosing is well tolerated and associated with evidence of antitumor activity . Exploration of alternative dosing regimens and combinatorial therapies with vaccines , targeted therapies , and /or other checkpoint inhibitors is warranted BACKGROUND Blockade of programmed death 1 ( PD-1 ) , an inhibitory receptor expressed by T cells , can overcome immune resistance . We assessed the antitumor activity and safety of BMS-936558 , an antibody that specifically blocks PD-1 . METHODS We enrolled patients with advanced melanoma , non-small-cell lung cancer , castration-resistant prostate cancer , or renal-cell or colorectal cancer to receive anti-PD-1 antibody at a dose of 0.1 to 10.0 mg per kilogram of body weight every 2 weeks . Response was assessed after each 8-week treatment cycle . Patients received up to 12 cycles until disease progression or a complete response occurred . RESULTS A total of 296 patients received treatment through February 24 , 2012 .  Grade 3 or 4 drug-related adverse events occurred in 14 % of patients ; there were three deaths from pulmonary toxicity . No maximum tolerated dose was defined . Adverse events consistent with immune-related causes were observed . Among 236 patients in whom response could be evaluated , objective responses ( complete or partial responses ) were observed in those with non-small-cell lung cancer , melanoma , or renal-cell cancer .  Cumulative response rates ( all doses ) were 18 % among patients with non-small-cell lung cancer ( 14 of 76 patients ) , 28 % among patients with melanoma ( 26 of 94 patients ) , and 27 % among patients with renal-cell cancer ( 9 of 33 patients ) . Responses were durable ; 20 of 31 responses lasted 1 year or more in patients with 1 year or more of follow-up . To assess the role of intratumoral PD-1 lig and ( PD-L1 ) expression in the modulation of the PD-1-PD-L1 pathway , immunohistochemical analysis was performed on pretreatment tumor specimens obtained from 42 patients . Of 17 patients with PD-L1-negative tumors , none had an objective response ; 9 of 25 patients ( 36 % ) with PD-L1-positive tumors had an objective response ( P=0.006 ) . CONCLUSIONS Anti-PD-1 antibody produced objective responses in approximately one in four to one in five patients with non-small-cell lung cancer , melanoma , or renal-cell cancer ; the adverse-event profile does not appear to preclude its use . Preliminary data suggest a relationship between PD-L1 expression on tumor cells and objective response . ( Funded by Bristol-Myers Squibb and others ; Clinical Trials.gov number , NCT00730639 . ) Therapies that target the programmed death-1 ( PD-1 ) receptor have shown unprecedented rates of durable clinical responses in patients with various cancer types . One mechanism by which cancer tissues limit the host immune response is via upregulation of PD-1 lig and ( PD-L1 ) and its ligation to PD-1 on antigen-specific CD8 + T cells ( termed adaptive immune resistance ) . Here we show that pre-existing CD8 + T cells distinctly located at the invasive tumour margin are associated with expression of the PD-1/PD-L1 immune inhibitory axis and may predict response to therapy . We analysed sample s from 46 patients with metastatic melanoma obtained before and during anti-PD-1 therapy ( pembrolizumab )  using quantitative immunohistochemistry , quantitative multiplex immunofluorescence , and next-generation sequencing for T-cell antigen receptors ( TCRs ) . In serially sample d tumours , patients responding to treatment showed proliferation of intratumoral CD8 + T cells that directly correlated with radiographic reduction in tumour size . Pre-treatment sample s obtained from responding patients showed higher numbers of CD8- , PD-1- and PD-L1-expressing cells at the invasive tumour margin and inside tumours , with close proximity between PD-1 and PD-L1 , and a more clonal TCR repertoire . Using multivariate analysis , we established a predictive model based on CD8 expression at the invasive margin and vali date d the model in an independent cohort of 15 patients . Our findings indicate that tumour regression after therapeutic PD-1 blockade requires pre-existing CD8 + T cells that are negatively regulated by PD-1/PD-L1-mediated adaptive immune resistance BACKGROUND Ipilimumab is an approved treatment for patients with advanced melanoma . We aim ed to assess ipilimumab as adjuvant therapy for patients with completely resected stage III melanoma at high risk of recurrence . METHODS We did a double-blind , phase 3 trial in patients with stage III cutaneous melanoma ( excluding lymph node metastasis ≤1 mm or in-transit metastasis ) with adequate resection of lymph nodes ( ie , the primary cutaneous melanoma must have been completely excised with adequate surgical margins ) who had not received previous systemic therapy for melanoma from 91 hospitals located in 19 countries . Patients were r and omly assigned ( 1:1 ) , central ly by an interactive voice response system , to receive intravenous infusions of 10 mg/kg ipilimumab or placebo every 3 weeks for four doses , then every 3 months for up to 3 years . Using a minimisation technique , r and omisation was stratified by disease stage and geographical region . The primary endpoint was recurrence-free survival , assessed by an independent review committee , and analysed by intention to treat . Enrollment is complete but the study is ongoing for follow-up for analysis of secondary endpoints . This trial is registered with EudraCT , number 2007 - 001974 - 10 , and Clinical Trials.gov , number NCT00636168 . FINDINGS Between July 10 , 2008 , and Aug 1 , 2011 , 951 patients were r and omly assigned to ipilimumab ( n=475 ) or placebo ( n=476 ) , all of whom were included in the intention-to-treat analyses . At a median follow-up of 2·74 years ( IQR 2·28 - 3·22 ) , there were 528 recurrence-free survival events ( 234 in the ipilimumab group vs 294 in the placebo group ) . Median recurrence-free survival was 26·1 months ( 95 % CI 19·3 - 39·3 ) in the ipilimumab group versus 17·1 months ( 95 % CI 13·4 - 21·6 ) in the placebo group ( hazard ratio 0·75 ; 95 % CI 0·64 - 0·90 ; p=0·0013 ) ; 3-year recurrence-free survival was 46·5 % ( 95 % CI 41·5 - 51·3 ) in the ipilimumab group versus 34·8 % ( 30·1 - 39·5 ) in the placebo group . The most common grade 3 - 4 immune-related adverse events in the ipilimumab group were gastrointestinal ( 75 [ 16 % ] vs four [ < 1 % ] in the placebo group ) , hepatic ( 50 [ 11 % ] vs one [ < 1 % ] ) , and endocrine ( 40 [ 8 % ] vs none ) . Adverse events led to discontinuation of treatment in 245 ( 52 % ) of 471 patients who started ipilimumab ( 182 [ 39 % ] during the initial treatment period of four doses ) . Five patients ( 1 % ) died due to drug-related adverse events . Five ( 1 % ) participants died because of drug-related adverse events in the ipilimumab group ; three patients died because of colitis ( two with gastrointestinal perforation ) , one patient because of myocarditis , and one patient because of multiorgan failure with Guillain-Barré syndrome . INTERPRETATION Adjuvant ipilimumab significantly improved recurrence-free survival for patients with completely resected high-risk stage III melanoma . The adverse event profile was consistent with that observed in advanced melanoma , but at higher incidences in particular for endocrinopathies . The risk-benefit ratio of adjuvant ipilimumab at this dose and schedule requires additional assessment based on distant metastasis-free survival and overall survival endpoints to define its definitive value . FUNDING Bristol-Myers Squibb BACKGROUND Phase 1 and 2 clinical trials of the BRAF kinase inhibitor vemurafenib ( PLX4032 ) have shown response rates of more than 50 % in patients with metastatic melanoma with the BRAF V600E mutation . METHODS We conducted a phase 3 r and omized clinical trial comparing vemurafenib with dacarbazine in 675 patients with previously untreated , metastatic melanoma with the BRAF V600E mutation . Patients were r and omly assigned to receive either vemurafenib ( 960 mg orally twice daily ) or dacarbazine ( 1000 mg per square meter of body-surface area intravenously every 3 weeks ) . Co primary end points were rates of overall and progression-free survival . Secondary end points included the response rate , response duration , and safety . A final analysis was planned after 196 deaths and an interim analysis after 98 deaths . RESULTS At 6 months , overall survival was 84 % ( 95 % confidence interval [ CI ] , 78 to 89 ) in the vemurafenib group and 64 % ( 95 % CI , 56 to 73 ) in the dacarbazine group . In the interim analysis for overall survival and final analysis for progression-free survival , vemurafenib was associated with a relative reduction of 63 % in the risk of death and of 74 % in the risk of either death or disease progression , as compared with dacarbazine ( P<0.001 for both comparisons ) . After review of the interim analysis by an independent data and safety monitoring board , crossover from dacarbazine to vemurafenib was recommended . Response rates were 48 % for vemurafenib and 5 % for dacarbazine . Common adverse events associated with vemurafenib were arthralgia , rash , fatigue , alopecia , keratoacanthoma or squamous-cell carcinoma , photosensitivity , nausea , and diarrhea ; 38 % of patients required dose modification because of toxic effects . CONCLUSIONS Vemurafenib produced improved rates of overall and progression-free survival in patients with previously untreated melanoma with the BRAF V600E mutation . ( Funded by Hoffmann-La Roche ; BRIM-3 Clinical Trials.gov number , NCT01006980 . ) BACKGROUND Nivolumab , a fully human IgG4 PD-1 immune checkpoint inhibitor antibody , can result in durable responses in patients with melanoma who have progressed after ipilimumab and BRAF inhibitors . We assessed the efficacy and safety of nivolumab compared with investigator 's choice of chemotherapy ( ICC ) as a second-line or later-line treatment in patients with advanced melanoma . METHODS In this r and omised , controlled , open-label , phase 3 trial , we recruited patients at 90 sites in 14 countries . Eligible patients were 18 years or older , had unresectable or metastatic melanoma , and progressed after ipil 
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Collectively , these results demonstrate that immune checkpoint inhibitors have superior outcomes compared to conventional chemotherapies or vaccination , and support the results of recent r and omized trials that showed superior outcomes with anti-PD-1 agents over ipilimumab in unresectable metastatic cutaneous melanoma patients