Faculty Bibliography

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 .).

Background: Immune checkpoint inhibitors directed against programmed death-1 (PD-1) and cytotoxic T lymphocyte antigen-4 (CTLA-4) can provide long term benefit to a subset of cancer patients. Optimal patient selection remains challenging. Using serum mass spectrometry, we have developed a predictive test associated with prolonged survival of patients on anti-PD-1 therapy. Refinement of the test defined a subgroup of patients with particularly poor survival. Analysis of protein set enrichment analysis (PSEA) generated several hypotheses about the biological processes associated with the tests. Materials and Methods: MALDI mass spectra were generated from pretreatment serum samples from 119 patients with metastatic melanoma (MM) treated with nivolumab at the Moffitt Cancer Center. A classifier development platform optimized for creation of multivariate molecular diagnostic tests which can generalize well to independent datasets was employed to create a test that identified patients with prolonged overall survival. This test classified samples into two groups: group 1 with prolonged survival and group 2 with short survival. The classifier was validated using two independent cohorts of MM patients receiving anti-PD-1 agents: 30 patients from Yale University (YU) and 25 patients, most treated with pembrolizumab, from Massachusetts General Hospital (MGH). The test was also applied to pretreatment sera collected from 21 patients from Yale that received combination PD-1/CTLA-4 blockade. The difference in outcomes between patients in group 1 and group 2 were assessed using log-rank p values and Cox proportional hazard ratios (HRs). Results: Of the 119 patients used in the test set, 34 (29%) were classified as group 1. Group 1 had longer overall survival (OS) and progression-free survival (p = 0.002, p = 0.014 respectively), with twoyear survival of 67%. Thirteen patients (43%) from the Yale cohort and eleven patients (44%) from the MGH cohort were classified as Group 1. In the combined analysis of validation sera sets from patients receiving anti-PD-1 agents, patients classified as Group 1 had better OS than Group 2 (p < 0.0001, HR = 0.162); their two-year survival was 86%. Within the cohort of patients receiving combination PD-1/CTLA-4 blockade, 13 (62%) were classified as Group 1. Two-year survival was 83% in Group 1 and 63% in Group 2. Further refinement of the test identified patients who had either better and worse outcome among those classified as Group 2. The difference appears to be related to proteins associated with Th1 versus Th2 mediated immunity in these patients. Conclusions: A serum proteomic test identified a subgroup of patients with prolonged survival with anti-PD-1 therapy. High two-year survival in the Group 1 cohort may indicate that the test has potential utility in identifying patients who derive significant benefit from anti-PD-1 monotherapy and might gain little benefit from the addition of an anti-CTLA-4 agent. Further stratification of patients classified as Group 2 identified patients who can benefit from treatment from PD-1 monotherapy. Follow-up was 2 years for OS, and the numbers in the validation set are small, indicating that further validation is necessary. Detection of biological differences in sensitivity and resistance using PSEA methods applied to mass spectral data suggest potentially important lines of further investigation

Immune checkpoint blockers (ICB) have become pivotal therapies in the clinical armamentarium against metastatic melanoma (MMel). Given the frequency of immune related adverse events and increasing use of ICB, predictors of response to CTLA-4 and/or PD-1 blockade represent unmet clinical needs. Using a systems biology-based approach to an assessment of 779 paired blood and tumor markers in 37 stage III MMel patients, we analyzed association between blood immune parameters and the functional immune reactivity of tumor-infiltrating cells after ex vivo exposure to ICB. Based on this assay, we retrospectively observed, in eight cohorts enrolling 190 MMel patients treated with ipilimumab, that PD-L1 expression on peripheral T cells was prognostic on overall and progression-free survival. Moreover, detectable CD137 on circulating CD8+ T cells was associated with the disease-free status of resected stage III MMel patients after adjuvant ipilimumab + nivolumab (but not nivolumab alone). These biomarkers should be validated in prospective trials in MMel.The clinical management of metastatic melanoma requires predictors of the response to checkpoint blockade. Here, the authors use immunological assays to identify potential prognostic/predictive biomarkers in circulating blood cells and in tumor-infiltrating lymphocytes from patients with resected stage III melanoma.

Background: NIVO and IPI are approved as monotherapy and in combination for treatment of MEL. These treatments are associated with select (potentially immune-related) adverse events (AEs) of the GI tract, most commonly diarrhea and colitis. We describe the management of GI toxicity in patients (pts) treated with NIVO+IPI or IPI from phase II (CheckMate 069) and III (CheckMate 067) trials. Methods: Pts received NIVO 1 mg/kg + IPI 3 mg/kg Q3W x 4, followed by NIVO 3 mg/kg Q2W until progression or unacceptable toxicity, or IPI 3 mg/kg Q3W x 4, followed by placebo. Minimum follow-up was 2 yrs for CheckMate 069 and 18 months for CheckMate 067. Results: Of 407 pts treated with NIVO+IPI, 195 (48%) experienced any grade select GI AEs, and of 357 pts treated with IPI, 132 (37%) experienced any grade select GI AEs. Grade 3/4 select GI AEs were reported in 67 (16%) pts treated with NIVO+IPI and in 41 (11%) pts treated with IPI; median time to onset was 7.1 weeks (range 0.9- 48.9) with NIVO+IPI and 7.3 weeks (range 0.6-14.9) with IPI. To manage these AEs, immune-modulating medications (IMM) were used in 61/67 (91%) pts in the NIVO+IPI group and in 41/41 (100%) in the IPI group. Corticosteroids (CS) were used in 61/67 (91%) and 41/41 (100%) pts, and infliximab (IFX) was used in 21/67 (31%) and 14/41 (34%) pts in the NIVO+IPI and IPI groups, respectively. In the NIVO+IPI group, the resolution rate of grade 3/4 select GI AEs was 96%, 97%, and 95% with a median time to resolution of 3.3, 3.0, and 3.9 weeks in all treated pts, CS, and CS+IFX managed pts, respectively; 88%, 92%, and 79% resolved with a median time to resolution of 3.9, 2.4, and 7.8 weeks in the IPI group, respectively. Objective response rates (ORR) were unchanged in the presence of any grade select GI AEs, or by using CS or CS+IFX (Table). Conclusions: NIVO+IPI or IPI alone is associated with a high incidence of GI select AEs, but most are effectively managed by IMMs, which do not appear to inhibit tumor response

Background: PD-1 blocking antibodies have significant efficacy in the treatment of melanoma; however, many patients fail to respond and resistance mechanisms remain unknown. We addressed the role of Tregs, an immunosuppressive T-cell population, in patient outcome after treatment with nivolumab. Methods: Peripheral blood mononuclear cells (PBMC) were obtained from patients on trials with nivolumab as adjuvant therapy for resected disease or as treatment for metastatic melanoma. To measure suppression, Tregs were flow-sorted from PBMC and evaluated in allogeneic mixed lymphocyte reactions. Tregs and conventional CD4 T-cells were evaluated for gene expression changes by RNAsequencing. Tregs percentages and phosphorylated STAT3 (pSTAT3) expression were evaluated by flow cytometry. The effects of PD-1 blockade with nivolumab were evaluated in vitro using T-cells from baseline patient PBMC samples. Results: Tregs from responding patients or adjuvant patients without evidence of disease (NED) had reduced suppressive function post-nivolumab (p < 0.05), but no changes were observed in relapsing/nonresponding patients; their Tregs were more suppressive than NED/responding Tregs (p < 0.001). NED T had unique gene expression changes and associated pathways post-nivolumab compared to relapsing patient Tregs and conventional CD4 T-cells, including up-regulation of proliferation pathways (q < 8e-19) and downregulation of oxidative phosphorylation (q < 7e-5). NED T had upregulation of pSTAT3 expression post-nivolumab (p < 0.05), which was not observed in relapsing patients. Evaluation of Tregs from patients with active disease also showed upregulation of pSTAT3 in responders (p < 0.05) but not non-responders. The relative increase in T pSTAT3 was associated with increased overall survival (R²= 0.49, p < 0.05). In vitro assays using PD-1 blocking antibodies recapitulated the increase in pSTAT3 (p < 0.05) and Treg percentages (p < 0.001), which were diminished with the addition of a STAT3 inhibitor (p < 0.01). Conclusions: These results demonstrate previously unknown roles of decreased Treg suppressive function and induction of STAT3 as biomarkers of patient's outcome to nivolumab therapy

PD-1 blockade has remarkable response rates in the treatment of melanoma; however, many patients fail to respond, and biomarkers and mechanisms of response remain unknown. We investigated the roles of Tregs, a population of immunosuppressive T-cells, in patient response to nivolumab. Tregs had a decrease in suppressive function in patients with positive outcomes (p=0.03), but not in patients with negative outcomes. Patients with no evidence of disease (NED) displayed increased percentages of Tregs post-nivolumab (p=0.04), but relapsing patients did not. RNA-seq analysis revealed genes significantly changed after treatment were distinct between Tcons and Tregs (~13% overlap) and between NED and relapsing patient Tregs (~2% overlap). Pathway analysis showed an increase in proliferation associated pathways in NED patient Tregs, but not relapsing patients. We found increased phosphoSTAT3 (pSTAT3) expression in Tregs from patients with positive outcomes (p=0.01), but not in patients with negative outcomes. Mechanistically, in vitro culturing of T-cells with alphaPD-1 resulted in increases in pSTAT3 expression (p=0.03) and increased percentages of Tregs (p=0.001). Culturing with alphaPD-1 also enhanced production of IL-10 (p=0.02), and the addition of a STAT3 inhibitor reduced the increases in IL-10 levels (p=0.01) and Treg percentages (p=0.01). The addition of an IL-10 neutralizing antibody also reduced the increased Tregs resulting from alphaPD-1 (p=0.01). These results support a model in which PD-1 blockade increases pSTAT3 expression leading to enhanced IL-10 production and Treg percentages, suggesting that pSTAT3 induction and reduced suppressive function are biomarkers of melanoma patient response to nivolumab

Importance: Immune checkpoint inhibitors have demonstrated atypical response patterns, which may not be fully captured by conventional response criteria. There is a need to better understand the potential benefit of continued immune checkpoint inhibition beyond progression. Objective: To evaluate the safety and potential benefit of nivolumab (anti-programmed cell death receptor 1) monotherapy beyond Response Evaluation Criteria in Solid Tumors (RECIST) v1.1-defined progression. Design, Setting, and Participants: Pooled, retrospective analysis of data from phase 3 trials of nivolumab in treatment-naive patients with advanced melanoma (CheckMate 066 or CheckMate 067) conducted at academic and clinical cancer centers. Participants were patients treated beyond first disease progression, defined as those who received their last dose of nivolumab more than 6 weeks after progression (TBP group); and patients not treated beyond progression, who discontinued nivolumab therapy before or at progression (non-TBP group). Data analyses were conducted from November 6, 2015, to January 11, 2017. Interventions: Nivolumab (3 mg/kg every 2 weeks) administered until progression or unacceptable toxic effects. Patients could be treated beyond progression if deriving apparent clinical benefit and tolerating study drug, at the investigator's discretion. Main Outcomes and Measures: Tumor response and safety in TBP and non-TBP patients. Results: Among 526 randomized patients (39% [n = 203] female; median age, 62 years [range, 18-90 years]), 306 (58%) experienced disease progression, including 85 (28%) TBP patients and 221 (72%) non-TBP patients. Twenty-four (28%) of the TBP patients had a target lesion reduction of greater than 30% after progression compared with baseline (TBP>30% group). At the time of this analysis, 65 (76%) TBP patients and 21 (87%) TBP>30% patients were still alive; 27 (32%) and 11 (46%), respectively, continued to receive treatment. Median (range) time from progression to last dose of treatment was 4.7 (1.4-25.8) months for TBP patients and 7.6 (2.4-19.4) months for TBP>30% patients. Median (range) time from progression to greater than 30% tumor reduction was 1.4 (0.2-7.0) months. Treatment-related select grade 3 to 4 adverse events were similar in the TBP and non-TBP groups (5 [6%] and 9 [4%], respectively). Conclusions and Relevance: A substantial proportion of selected patients treated with frontline nivolumab who were clinically stable and judged to be eligible for treatment beyond RECIST v1.1-defined progression by the treating investigators derived apparent clinical benefit without compromising safety. Further analysis will help define the potential benefit of continued nivolumab treatment beyond progression. Trial Registration: clinicaltrials.gov Identifiers: NCT01721772 (CheckMate 066) and NCT01844505 (CheckMate 067).