Faculty Bibliography

Background: NIVO and IPI are immune checkpoint inhibitors approved for advanced melanoma. IPI is also approved in the US for resected stage III melanoma, based on a phase 3 trial demonstrating an improvement in recurrence-free survival (RFS). We report the first results of a phase 3 trial designed to evaluate NIVO vs IPI for resected stage III/IV melanoma at high risk of recurrence. Methods: In this randomized, double-blind trial, eligible patients (pts) included those >=15 yrs of age who underwent complete resection of stage IIIb/c or IV melanoma. 906 pts were randomized (stratified by stage and PD-L1 status) 1:1 to receive NIVO 3 mg/ kg (n=453) every 2 wks or IPI 10 mg/kg (n=453) every 3 wks for 4 doses, then every 12 wks (from week 24) for up to 1 yr, disease recurrence, or unacceptable toxicity. The primary endpoint was RFS in the intent-to-treat population. Results: Overall, 34%/47%/19% of pts had stage IIIb/IIIc/IV; 32%, ulcerated primary; 48%, macroscopic lymph node involvement; and 42%, BRAF mutation. At a median follow-up of 18.5 mo, NIVO significantly improved RFS vs IPI (Table). Results from prespecified subgroup analyses demonstrated consistent hazard ratios favoring NIVO. Conclusions: NIVO as adjuvant therapy significantly improved RFS vs IPI for pts with stage III/IV melanoma at high risk of recurrence and demonstrated a superior safety profile. (Table Presented)

Histone acetylation and the families of enzymes responsible for controlling these epigenetic marks have been implicated in regulating T-cell maturation and phenotype. Here, we demonstrate a previously undefined role of histone deacetylase 11 (HDAC11) in regulating T-cell effector functions. Using EGFP-HDAC11 transgenic reporter mice, we found that HDAC11 expression was lower in effector relative to naive and central memory T-cell populations, and activation of resting T-cells resulted in its decreased expression. Experiments using HDAC11 knockout (KO) mice revealed that T-cells from these mice displayed enhanced proliferation, pro-inflammatory cytokine production and effector molecule expression. Additionally, HDAC11KO T-cells had increased expression of Eomesodermin (Eomes) and TBX21 (Tbet), transcription factors previously shown to regulate inflammatory cytokine and effector molecule production. Conversely, overexpression of HDAC11 resulted in decreased expression of these genes. Chromatin immunoprecipitation showed the presence of HDAC11 at the Eomes and Tbet gene promoters in resting T-cells, where it rapidly disassociated following T-cell activation. In vivo, HDAC11KO T-cells were refractory to tolerance induction. HDAC11KO T-cells also mediated accelerated onset of acute graft-vs-host disease (GvHD) in a murine model, characterized by increased proliferation of T-cells and expression of IFNgamma, TNF and EOMES. Additionally, adoptive transfer of HDAC11KO T-cells resulted in significantly reduced tumor burden in a murine B-cell lymphoma model. Taken together, these data demonstrate a previously unknown role of HDAC11 as a negative epigenetic regulator of T-cell effector phenotype and function.

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

BACKGROUND: Despite unprecedented efficacy across multiple tumor types, immune checkpoint inhibitor therapy is associated with a unique and wide spectrum of immune-related adverse events (irAEs), including neurologic events ranging from mild headache to potentially life-threatening encephalitis. Here, we summarize neurologic irAEs associated with nivolumab and ipilimumab melanoma treatment, present cases of treatment-related encephalitis, and provide practical guidance on diagnosis and management. METHODS: We searched a Global Pharmacovigilance and Epidemiology database for neurologic irAEs reported over an 8-year period in patients with advanced melanoma receiving nivolumab with or without ipilimumab from 12 studies sponsored by Bristol-Myers Squibb. Serious neurologic irAEs were reviewed, and relationship to nivolumab or ipilimumab was assigned. RESULTS: In our search of 3,763 patients, 35 patients (0.93%) presented with 43 serious neurologic irAEs, including neuropathy (n = 22), noninfective meningitis (n = 5), encephalitis (n = 6), neuromuscular disorders (n = 3), and nonspecific adverse events (n = 7). Study drug was discontinued (n = 20), interrupted (n = 8), or unchanged (n = 7). Most neurologic irAEs resolved (26/35 patients; 75%). Overall, median time to onset was 45 days (range 1-170) and to resolution was 32 days (2-809+). Median time to onset of encephalitis was 55.5 days (range 18-297); four cases resolved and one was fatal. CONCLUSION: Both oncologists and neurologists need to be aware of signs and symptoms of serious but uncommon neurologic irAEs associated with checkpoint inhibitors. Prompt diagnosis and management using an established algorithm are critical to minimize serious complications from these neurologic irAEs. The Oncologist 2017;22:1-10Implications for Practice: With increasing use of checkpoint inhibitors in cancer, practicing oncologists need to be aware of the potential risk of neurologic immune-related adverse events and be able to provide prompt treatment of this uncommon, but potentially serious, class of adverse events. We summarize neurologic adverse events related to nivolumab alone or in combination with ipilimumab in patients with advanced melanoma from 12 studies and examine in depth 6 cases of encephalitis. We also provide input and guidance on the existing neurologic adverse events management algorithm for nivolumab and ipilimumab.

Immunotherapy has moved to the center stage of cancer treatment with the recent success of trials in solid tumors with PD-1/PD-L1 axis blockade. Programmed death-1 or PD-1 is a checkpoint molecule on T cells that plays a vital role in limiting adaptive immune responses and preventing autoimmune and auto-inflammatory reactivity in the normal host. In cancer patients, PD-1 expression is very high on T cells in the tumor microenvironment, and PD-L1, its primary ligand, is variably expressed on tumor cells and antigen-presenting cells within tumors, providing a potent inhibitory influence within the tumor microenvironment. While PD-L1 expression on tumors is often regarded as a negative prognostic factor, it is clearly associated with a positive outcome for treatment with PD-1/PD-L1 blocking antibodies, and has been used to select patients for this therapy. Responses of long duration, a minority of patients with atypical responses in which progression may precede tumor shrinkage, and a pattern of autoimmune side effects often seen with this class of drugs characterize therapy with PD-1/PD-L1 blocking drugs. While excellent efficacy has been seen with a limited number of tumor types, most epithelial cancers do not show responses of long duration with these agents. In the current review, we will briefly summarize the scientific background data supporting the development of PD-1/PD-L1 blockade, and then describe the track record of these antibodies in multiple different histologies ranging from melanoma and lung cancer to less common tumor types as well as discuss biomarkers that may assist in patient selection.

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

Purpose We conducted a retrospective analysis to assess the safety profile of nivolumab monotherapy in patients with advanced melanoma and describe the management of adverse events (AEs) using established safety guidelines. Patients and Methods Safety data were pooled from four studies, including two phase III trials, with patients who received nivolumab 3 mg/kg once every 2 weeks. We evaluated rate of treatment-related AEs, time to onset and resolution of select AEs (those with potential immunologic etiology), and impact of select AEs and suppressive immune-modulating agents (IMs) on antitumor efficacy. Results Among 576 patients, 71% (95% CI, 67% to 75%) experienced any-grade treatment-related AEs (most commonly fatigue [25%], pruritus [17%], diarrhea [13%], and rash [13%]), and 10% (95% CI, 8% to 13%) experienced grade 3 to 4 treatment-related AEs. No drug-related deaths were reported. Select AEs (occurring in 49% of patients) were most frequently skin related, GI, endocrine, and hepatic; grade 3 to 4 select AEs occurred in 4% of patients. Median time to onset of select AEs ranged from 5 weeks for skin to 15 weeks for renal AEs. Approximately 24% of patients received systemic IMs to manage select AEs, which in most cases resolved. Adjusting for number of doses, objective response rate (ORR) was significantly higher in patients who experienced treatment-related select AEs of any grade compared with those who did not. ORRs were similar in patients who did and patients who did not receive systemic IMs. Conclusion Treatment-related AEs with nivolumab monotherapy were primarily low grade, and most resolved with established safety guidelines. Use of IMs did not affect ORR, although treatment-related select AEs of any grade were associated with higher ORR, but no progression-free survival benefit.