Radiomic analysis of patient and inter-organ heterogeneity in response to immunotherapies and BRAF targeted therapy in metastatic melanoma.

Background: Variability in treatment response may be attributable to organ-level heterogeneity in tumor lesions. Radiomic analysis of medical images can elucidate non-invasive biomarkers of clinical outcome. Organ-specific radiomic comparison across immunotherapies and targeted therapies has not been previously reported. Methods: We queried UPMC Hillman Cancer Center registry for patients with metastatic melanoma (MEL) treated with immune checkpoint inhibitors (ICI) (anti-PD1/CTLA4 [ipilimumab+nivolumab; I+N] or anti-PD1 monotherapy) or BRAF targeted therapy. Best overall response was measured using RECIST v1.1. Lesions were segmented into discrete volume-of-interest with 400 radiomics features extracted. Overall and organ-specific machine-learning models were constructed to predict disease control (DC) versus progressive disease (PD) using XGBoost. Results: 291 MEL patients were identified, including 242 ICI (91 I+N, 151 PD1) and 49 BRAF. 667 metastases were analyzed, including 541 ICI (236 I+N, 305 PD1) and 126 BRAF. Across cohorts, baseline demographics included 39-47% female, 24-29% M1C, 24-46% M1D, and 61-80% with elevated LDH. Among patients experiencing DC, the organs with the greatest reduction were liver (-88%±12%, I+N; mean±S.E.M.) and lung (-72%±8%, I+N). For patients with multiple same-organ target lesions, the highest inter-lesion heterogeneity was observed in brain among patients who received ICI while no intra-organ heterogeneity was observed in BRAF. 267 patients were kept for radiomic modeling, including 221 ICI (86 I+N, 135 PD1) and 46 BRAF. Models consisting of optimized radiomic signatures classified DC/PD across I+N (AUC=0.85) and PD1 (0.71) and within individual organ sites (AUC=0.72∼0.94). Integration of clinical variables improved the models' performance. Comparison of models between treatments and across organ sites suggested mostly non-overlapping DC or PD features. Skewness, kurtosis, and informational measure of correlation (IMC) were among the radiomic features shared between overall response models. Kurtosis and IMC were also utilized by multiple organ-site models. Conclusions: Differential organ-specific response was observed across BRAF and ICI with within organ heterogeneity observed for ICI but not for BRAF. Radiomic features of organ-specific response demonstrated little overlap. Integrating clinical factors with radiomics improves the prediction of disease course outcome and prediction of tumor heterogeneity.

Society for Immunotherapy of Cancer (SITC) recommendations on intratumoral immunotherapy clinical trials (IICT): from premalignant to metastatic disease.

BACKGROUND: Intratumorally delivered immunotherapies have the potential to favorably alter the local tumor microenvironment and may stimulate systemic host immunity, offering an alternative or adjunct to other local and systemic treatments. Despite their potential, these therapies have had limited success in late-phase trials for advanced cancer resulting in few formal approvals. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to determine how to design clinical trials with the greatest chance of demonstrating the benefits of intratumoral immunotherapy for patients with cancers across all stages of pathogenesis. METHODS: An Intratumoral Immunotherapy Clinical Trials Expert Panel composed of international key stakeholders from academia and industry was assembled. A multiple choice/free response survey was distributed to the panel, and the results of this survey were discussed during a half-day consensus meeting. Key discussion points are summarized in the following manuscript. RESULTS: The panel determined unique clinical trial designs tailored to different stages of cancer development-from premalignant to unresectable/metastatic-that can maximize the chance of capturing the effect of intratumoral immunotherapies. Design elements discussed included study type, patient stratification and exclusion criteria, indications of randomization, study arm determination, endpoints, biological sample collection, and response assessment with biomarkers and imaging. Populations to prioritize for the study of intratumoral immunotherapy, including stage, type of cancer and line of treatment, were also discussed along with common barriers to the development of these local treatments. CONCLUSIONS: The SITC Intratumoral Immunotherapy Clinical Trials Expert Panel has identified key considerations for the design and implementation of studies that have the greatest potential to capture the effect of intratumorally delivered immunotherapies. With more effective and standardized trial designs, the potential of intratumoral immunotherapy can be realized and lead to regulatory approvals that will extend the benefit of these local treatments to the patients who need them the most.

Pharmacokinetic study of capivasertib and the CYP3A4 substrate midazolam in patients with advanced solid tumors.

PURPOSE: Capivasertib, a potent, selective inhibitor of all three AKT serine/threonine kinase (AKT) isoforms, is being evaluated in phase 3 trials in advanced breast and prostate cancer. This study evaluated the drug-drug interaction risk of capivasertib with the cytochrome P450 3A substrate midazolam in previously treated adults with advanced solid tumors. METHODS: Patients received oral capivasertib 400 mg twice daily (BID) on an intermittent schedule (4 days on/3 days off) starting on day 2 of cycle 1 (29 days) and on day 1 of each 28-day cycle thereafter. In cycle 1 only, patients received oral midazolam (1 mg) on day 1 (alone), and days 8 and 12 (3rd day off and 4th day on capivasertib, respectively). Midazolam pharmacokinetics on days 8 and 12 were analyzed versus day 1. Capivasertib, with or without standard-of-care treatment, was continued in patients deemed likely to benefit. Safety and exploratory efficacy analyses were conducted. RESULTS: Capivasertib-midazolam coadministration increased midazolam exposure (n = 21): geometric mean ratio (90% confidence interval) AUCinf and Cmax was 1.13 (0.97-1.32) and 1.15 (0.99-1.33) for day 8 versus day 1, and 1.75 (1.50-2.05) and 1.25 (1.08-1.46) for day 12 versus day 1. The capivasertib safety profile was manageable when administered with or without midazolam. Two patients had partial responses to treatment. CONCLUSION: The up to 1.75-fold increase in midazolam exposure indicates capivasertib is a weak CYP3A inhibitor at 400 mg BID on an intermittent schedule. Capivasertib was well tolerated; exploratory efficacy analysis demonstrated evidence of clinical activity in this heavily pre-treated population. CLINICALTRIALS: gov: NCT04958226.

Th2 Cells Are Associated with Tumor Recurrence Following Radiation.

The curative treatment of multiple solid tumors, including head and neck squamous cell carcinoma (HNSCC), utilizes radiation. The outcomes for HPV/p16-negative HNSCC are significantly worse than HPV/p16-positive tumors, with increased radiation resistance leading to worse locoregional recurrence (LRR) and ultimately death. This study analyzed the relationship between immune function and outcomes following radiation in HPV/p16-negative tumors to identify mechanisms of radiation resistance and prognostic immune biomarkers. A discovery cohort of 94 patients with HNSCC treated uniformly with surgery and adjuvant radiation and a validation cohort of 97 similarly treated patients were utilized. Tumor immune infiltrates were derived from RNAseq gene expression. The immune cell types significantly associated with outcomes in the discovery cohort were examined in the independent validation cohort. A positive association between high Th2 infiltration and LRR was identified in the discovery cohort and validated in the validation cohort. Tumor mutations in CREBBP/EP300 and CASP8 were significantly associated with Th2 infiltration. A pathway analysis of genes correlated with Th2 cells revealed the potential repression of the antitumor immune response and the activation of BRCA1-associated DNA damage repair in multiple cohorts. The Th2 infiltrates were enriched in the HPV/p16-negative HNSCC tumors and associated with LRR and mutations in CASP8, CREBBP/EP300, and pathways previously shown to impact the response to radiation.

Final results of urelumab, an anti-CD137 agonist monoclonal antibody, in combination with cetuximab or nivolumab in patients with advanced solid tumors.

BACKGROUND: Resistance to immune checkpoint inhibitors and targeted treatments for cancer is common; thus, novel immunotherapy agents are needed. Urelumab is a monoclonal antibody agonist that binds to CD137 receptors expressed on T cells. Here, we report two studies that evaluated urelumab in combination with cetuximab or nivolumab in patients with select, advanced solid tumors. METHODS: CA186-018: Patients with metastatic colorectal cancer or metastatic squamous cell carcinoma of the head and neck (SCCHN) were treated in a dose-evaluation phase with urelumab 0.1 mg/kg (urelumab-0.1) every 3 weeks (Q3W)+cetuximab 250 mg/m2 (cetuximab-250) weekly; and in a dose-expansion phase with urelumab 8 mg flat dose (urelumab-8) Q3W+cetuximab-250 weekly. CA186-107: The dose-escalation phase included patients with previously treated advanced solid tumors (or treated or treatment-naive melanoma); patients received urelumab 3 mg flat dose (urelumab-3) or urelumab-8 every 4 weeks+nivolumab 3 mg/kg (nivolumab-3) or 240 mg (nivolumab-240) every 2 weeks. In the expansion phase, patients with melanoma, non-small cell lung cancer, or SCCHN were treated with urelumab-8+nivolumab-240. Primary endpoints were safety and tolerability, and the secondary endpoint included efficacy assessments. RESULTS: CA186-018: 66 patients received study treatment. The most frequent treatment-related adverse events (TRAEs) were fatigue (75%; n=3) with urelumab-0.1+cetuximab-250 and dermatitis (45%; n=28) with urelumab-8+cetuximab-250. Three patients (5%) discontinued due to TRAE(s) (with urelumab-8+cetuximab-250). One patient with SCCHN had a partial response (objective response rate (ORR) 5%, with urelumab-8+cetuximab-250).CA186-107: 134 patients received study treatment. Fatigue was the most common TRAE (32%; n=2 with urelumab-3+nivolumab-3; n=1 with urelumab-8+nivolumab-3; n=40 with urelumab-8+nivolumab-240). Nine patients (7%) discontinued due to TRAE(s) (n=1 with urelumab-3+nivolumab-3; n=8 with urelumab-8+nivolumab-240). Patients with melanoma naive to anti-PD-1 therapy exhibited the highest ORR (49%; n=21 with urelumab-8+nivolumab-240). Intratumoral gene expression in immune-related pathways (CD3, CD8, CXCL9, GZMB) increased on treatment with urelumab+nivolumab. CONCLUSIONS: Although the addition of urelumab at these doses was tolerable, preliminary response rates did not indicate an evident additive benefit. Nevertheless, the positive pharmacodynamics effects observed with urelumab and the high response rate in treatment-naive patients with melanoma warrant further investigation of other anti-CD137 agonist agents for treatment of cancer. TRIAL REGISTRATION NUMBERS: NCT02110082; NCT02253992.

Pembrolizumab versus placebo as adjuvant therapy in resected stage IIB or IIC melanoma: Outcomes in histopathologic subgroups from the randomized, double-blind, phase 3 KEYNOTE-716 trial.

BACKGROUND: Adjuvant pembrolizumab significantly improved recurrence-free survival (RFS) and distant metastasis-free survival (DMFS) versus placebo in the phase 3 KEYNOTE-716 study of resected stage IIB or IIC melanoma. At the prespecified third interim analysis (data cut-off, January 4, 2022), the HR for RFS in the overall population was 0.64 (95% CI, 0.50 to 0.84) and the HR for DMFS was 0.64 (95% CI, 0.47 to 0.88). We present a post hoc analysis of efficacy by subtypes defined by histopathologic characteristics. METHODS: Patients aged ≥12 years with newly diagnosed, resected stage IIB or IIC melanoma were randomly assigned (1:1) to pembrolizumab 200 mg every 3 weeks (2 mg/kg up to 200 mg for pediatric patients) or placebo. The primary end point was RFS per investigator review; DMFS per investigator review was secondary. Subgroups of interest were melanoma subtype (nodular vs non-nodular), tumor thickness (≤4 mm vs >4 mm), presence of ulceration (yes vs no), mitotic rate (<5 per mm2 (median) vs ≥5 per mm2), and presence of tumor-infiltrating lymphocytes (TILs; absent vs present). RESULTS: Between September 23, 2018, and November 4, 2020, 976 patients were assigned to pembrolizumab (n=487) or placebo (n=489). Median follow-up was 27.4 months (range, 14.0-39.4). The HR (95% CI) for RFS was 0.54 (0.37 to 0.79) for nodular and 0.77 (0.53 to 1.11) for non-nodular melanoma; 0.57 (0.37 to 0.89) for thickness ≤4 mm and 0.69 (0.50 to 0.96) for >4 mm; 0.66 (0.50 to 0.89) for ulceration and 0.57 (0.32 to 1.03) for no ulceration; 0.57 (0.35 to 0.92) for mitotic rate <5 per mm2 and 0.57 (0.40 to 0.80) for ≥5 per mm2; and 0.89 (0.52 to 1.54) for TILs absent and 0.51 (0.34 to 0.76) for TILs present. DMFS results were similar. In a Cox multivariate analysis, treatment arm, tumor thickness, and mitotic rate were significant independent factors for RFS, and treatment arm and mitotic rate were significant independent factors for DMFS. CONCLUSIONS: In this post hoc analysis, the benefit of pembrolizumab was largely consistent with the overall study population regardless of histopathologic characteristics. These results support the use of adjuvant pembrolizumab in patients with resected stage IIB or IIC melanoma. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, NCT03553836.

Pembrolizumab Versus Placebo as Adjuvant Therapy in Resected Stage IIB or IIC Melanoma: Final Analysis of Distant Metastasis-Free Survival in the Phase III KEYNOTE-716 Study.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Pembrolizumab adjuvant therapy was shown to significantly improve recurrence-free survival (RFS) and distant metastasis-free survival (DMFS) in patients with resected stage IIB or IIC melanoma in earlier analyses of the randomized, double-blind, phase III KEYNOTE-716 study (ClinicalTrials.gov identifier: NCT03553836). We report results of the protocol-specified final analysis of DMFS for KEYNOTE-716. Overall, 976 patients were randomly allocated to pembrolizumab (n = 487) or placebo (n = 489). As of January 4, 2023, median follow-up was 39.4 months (range, 26.0-51.4 months). The median DMFS was not reached in either treatment group, and the estimated 36-month DMFS was 84.4% for pembrolizumab and 74.7% for placebo (hazard ratio [HR], 0.59 [95% CI, 0.44 to 0.79]). The median RFS was not reached in either treatment group, and the estimated 36-month RFS was 76.2% for pembrolizumab and 63.4% for placebo (HR, 0.62 [95% CI, 0.49 to 0.79]). DMFS and RFS results were consistent across most prespecified subgroups, including stage IIB and stage IIC melanoma. The safety profile of pembrolizumab was manageable and consistent with previous reports. These results continue to support the use of pembrolizumab adjuvant therapy in patients with resected stage IIB or IIC melanoma.

US physician perspective on the use of biomarker and ctDNA testing in patients with melanoma.

New treatments have increased survival of patients with melanoma, and methods to monitor patients throughout the disease process are needed. Circulating tumor DNA (ctDNA) is a predictive and prognostic biomarker that may allow routine, real-time monitoring of disease status. We surveyed 44 US physicians to understand their preferences and practice patterns for biomarker and ctDNA testing in their patients with melanoma. Tumor biomarker testing was often ordered in stage IIIA-IV patients. Barriers to biomarker testing include insufficient tissue (60%) and lack of insurance coverage (54%). ctDNA testing was ordered by 16-18% of physicians for stages II-IV. Reasons for not using ctDNA testing included lack of prospective data (41%), ctDNA testing used for research only (18%), and others. Physicians (≥74%) believed that ctDNA assays could help with monitoring and treatment selection throughout the disease process. Physicians consider ctDNA testing potentially valuable for clinical decision-making but cited concerns that should be addressed.

Rapidly Evolving Pre- and Post-surgical Systemic Treatment of Melanoma.

With the development of effective BRAF-targeted and immune-checkpoint immunotherapies for metastatic melanoma, clinical trials are moving these treatments into earlier adjuvant and perioperative settings. BRAF-targeted therapy is a standard of care in resected stage III-IV melanoma, while anti-programmed death-1 (PD1) immunotherapy is now a standard of care option in resected stage IIB through IV disease. With both modalities, recurrence-free survival and distant-metastasis-free survival are improved by a relative 35-50%, yet no improvement in overall survival has been demonstrated. Neoadjuvant anti-PD1 therapy improves event-free survival by approximately an absolute 23%, although improvements in overall survival have yet to be demonstrated. Understanding which patients are most likely to recur and which are most likely to benefit from treatment is now the highest priority question in the field. Biomarker analyses, such as gene expression profiling of the primary lesion and circulating DNA, are preliminarily exciting as potential biomarkers, though each has drawbacks. As in the setting of metastatic disease, markers that inform positive outcomes include interferon-γ gene expression, PD-L1, and high tumor mutational burden, while negative predictors of outcome include circulating factors such as lactate dehydrogenase, interleukin-8, and C-reactive protein. Integrating and validating these markers into clinically relevant models is thus a high priority. Melanoma therapeutics continues to advance with combination adjuvant approaches now investigating anti-PD1 with lymphocyte activation gene 3 (LAG3), T-cell immunoreceptor with Ig and ITIM domains (TIGIT), and individualized neoantigen therapies. How this progress will be integrated into the management of a unique patient to reduce recurrence, limit toxicity, and avoid over-treatment will dominate clinical research and patient care over the next decade.

Unraveling the Therapeutic Benefit of Sequenced Chemo-immunotherapy.

Combination immune-checkpoint inhibition with chemotherapy is a clinical standard, yet concurrent administration may limit the full benefit of immunotherapy by blunting the proliferation and differentiation of CD8 T cells. Identifying patients in whom sequential chemo-immunotherapy or immunotherapy alone is feasible should be a priority to optimize long-term outcomes. See related article by Mariniello et al., p. 1833.

Nivolumab + Tacrolimus + Prednisone ± Ipilimumab for Kidney Transplant Recipients With Advanced Cutaneous Cancers.

PURPOSE: Cancer-related mortality rates among kidney transplant recipients (KTR) are high, but these patients have largely been excluded from trials of immune checkpoint inhibitors because of immunosuppression and risk of treatment-related allograft loss (TRAL). We conducted a prospective clinical trial testing nivolumab (NIVO) + tacrolimus (TACRO) + prednisone (PRED) ± ipilimumab (IPI) in KTR with advanced cutaneous cancers. METHODS: Adult KTR with advanced melanoma or basal, cutaneous squamous, or Merkel cell carcinomas were eligible. Immunosuppression was standardized to TACRO (serum trough 2-5 ng/mL) + PRED 5 mg once daily. Patients then received NIVO 480 mg IV once every 4 weeks. The primary composite end point was partial or complete (tumor) response (CR) or stable disease per RECIST v1.1 without allograft loss at 16W. Patients with progressive disease (PD) could receive IPI 1 mg/kg IV + NIVO 3 mg/kg once every 3 weeks × 4 followed by NIVO. Donor-derived cell-free DNA (dd-cfDNA) levels were measured approximately once every 2 weeks as a potential predictor of allograft rejection. RESULTS: Among eight evaluable patients, none met the trial's primary end point. All eight patients experienced PD on NIVO + TACRO + PRED; TRAL occurred in one patient. Six patients then received IPI + NIVO + TACRO + PRED. Best overall responses: two CR (one with TRAL) and four PD (one with TRAL). In total, 7 of 8 pre-NIVO tumor biopsies contained a paucity of infiltrating immune cells. In total, 2 of 5 on-NIVO biopsies demonstrated moderate immune infiltrates; both patients later experienced a CR to IPI + NIVO. In 2 of 3 patients with TRAL, dd-cfDNA elevations occurred 10 and 15 days before increases in serum creatinine. CONCLUSION: In most KTR with advanced skin cancer, TACRO + PRED provides insufficient allograft protection and compromises immune-mediated tumor regression after administration of NIVO ± IPI. Elevated dd-cfDNA levels can signal treatment-related allograft rejection earlier than rises in serum creatinine.

Facts and Hopes in Using Omics to Advance Combined Immunotherapy Strategies.

The field of oncology has been transformed by immune checkpoint inhibitors (ICI) and other immune-based agents; however, many patients do not receive a durable benefit. While biomarker assessments from pivotal ICI trials have uncovered certain mechanisms of resistance, results thus far have only scraped the surface. Mechanisms of resistance are as complex as the tumor microenvironment (TME) itself, and the development of effective therapeutic strategies will only be possible by building accurate models of the tumor-immune interface. With advancement of multi-omic technologies, high-resolution characterization of the TME is now possible. In addition to sequencing of bulk tumor, single-cell transcriptomic, proteomic, and epigenomic data as well as T-cell receptor profiling can now be simultaneously measured and compared between responders and nonresponders to ICI. Spatial sequencing and imaging platforms have further expanded the dimensionality of existing technologies. Rapid advancements in computation and data sharing strategies enable development of biologically interpretable machine learning models to integrate data from high-resolution, multi-omic platforms. These models catalyze the identification of resistance mechanisms and predictors of benefit in ICI-treated patients, providing scientific foundation for novel clinical trials. Moving forward, we propose a framework by which in silico screening, functional validation, and clinical trial biomarker assessment can be used for the advancement of combined immunotherapy strategies.

Individualised neoantigen therapy mRNA-4157 (V940) plus pembrolizumab versus pembrolizumab monotherapy in resected melanoma (KEYNOTE-942): a randomised, phase 2b study.

BACKGROUND: Checkpoint inhibitors are standard adjuvant treatment for stage IIB-IV resected melanoma, but many patients recur. Our study aimed to evaluate whether mRNA-4157 (V940), a novel mRNA-based individualised neoantigen therapy, combined with pembrolizumab, improved recurrence-free survival and distant metastasis-free survival versus pembrolizumab monotherapy in resected high-risk melanoma. METHODS: We did an open-label, randomised, phase 2b, adjuvant study of mRNA-4157 plus pembrolizumab versus pembrolizumab monotherapy in patients, enrolled from sites in the USA and Australia, with completely resected high-risk cutaneous melanoma. Patients with completely resected melanoma (stage IIIB-IV) were assigned 2:1 to receive open-label mRNA-4157 plus pembrolizumab or pembrolizumab monotherapy. mRNA-4157 was administered intramuscularly (maximum nine doses) and pembrolizumab intravenously (maximum 18 doses) in 3-week cycles. The primary endpoint was recurrence-free survival in the intention-to-treat population. This ongoing trial is registered at ClinicalTrials.gov, NCT03897881. FINDINGS: From July 18, 2019, to Sept 30, 2021, 157 patients were assigned to mRNA-4157 plus pembrolizumab combination therapy (n=107) or pembrolizumab monotherapy (n=50); median follow-up was 23 months and 24 months, respectively. Recurrence-free survival was longer with combination versus monotherapy (hazard ratio [HR] for recurrence or death, 0·561 [95% CI 0·309-1·017]; two-sided p=0·053), with lower recurrence or death event rate (24 [22%] of 107 vs 20 [40%] of 50); 18-month recurrence-free survival was 79% (95% CI 69·0-85·6) versus 62% (46·9-74·3). Most treatment-related adverse events were grade 1-2. Grade ≥3 treatment-related adverse events occurred in 25% of patients in the combination group and 18% of patients in the monotherapy group, with no mRNA-4157-related grade 4-5 events. Immune-mediated adverse event frequency was similar for the combination (37 [36%]) and monotherapy (18 [36%]) groups. INTERPRETATION: Adjuvant mRNA-4157 plus pembrolizumab prolonged recurrence-free survival versus pembrolizumab monotherapy in patients with resected high-risk melanoma and showed a manageable safety profile. These results provide evidence that an mRNA-based individualised neoantigen therapy might be beneficial in the adjuvant setting. FUNDING: Moderna in collaboration with Merck Sharp & Dohme, a subsidiary of Merck & Co, Rahway, NJ, USA.

Uncovering the Potential of CD40 Agonism to Enhance Immune Checkpoint Blockade.

In this CCR Translations, we discuss the therapeutic potential of CD40 agonism, which stimulates antigen-presenting cells (APC) to activate effector T and NK cells. CD40 agonism may lead to development of an interferon-activated, T cell-inflamed tumor microenvironment and has the potential to facilitate long-term response with immune checkpoint blockade. See related article by Weiss et al., p. 74.

Identification of tumor-intrinsic drivers of immune exclusion in acral melanoma.

Acral melanoma (AM) has distinct characteristics as compared with cutaneous melanoma and exhibits poor response to immune checkpoint inhibitors (ICIs). Tumor-intrinsic mechanisms of immune exclusion have been identified in many cancers but less studied in AM. We characterized clinically annotated tumors from patients diagnosed with AM at our institution in correlation with ICI response using whole transcriptome RNAseq, whole exome sequencing, CD8 immunohistochemistry, and multispectral immunofluorescence imaging. A defined interferon-γ-associated T cell-inflamed gene signature was used to categorize tumors into non-T cell-inflamed and T cell-inflamed phenotypes. In combination with AM tumors from two published studies, we systematically assessed the immune landscape of AM and detected differential gene expression and pathway activation in a non-T cell-inflamed tumor microenvironment (TME). Two single-cell(sc) RNAseq AM cohorts and 11 bulk RNAseq cohorts of various tumor types were used for independent validation on pathways associated with lack of ICI response. In total, 892 specimens were included in this study. 72.5% of AM tumors showed low expression of the T cell-inflamed gene signature, with 23.9% of total tumors categorized as the non-T cell-inflamed phenotype. Patients of low CD3+CD8+PD1+ intratumoral T cell density showed poor prognosis. We identified 11 oncogenic pathways significantly upregulated in non-T cell-inflamed relative to T cell-inflamed TME shared across all three acral cohorts (MYC, HGF, MITF, VEGF, EGFR, SP1, ERBB2, TFEB, SREBF1, SOX2, and CCND1). scRNAseq analysis revealed that tumor cell-expressing pathway scores were significantly higher in low versus high T cell-infiltrated AM tumors. We further demonstrated that the 11 pathways were enriched in ICI non-responders compared with responders across cancers, including AM, cutaneous melanoma, triple-negative breast cancer, and non-small cell lung cancer. Pathway activation was associated with low expression of interferon stimulated genes, suggesting suppression of antigen presentation. Across the 11 pathways, fatty acid synthase and CXCL8 were unifying downstream target molecules suggesting potential nodes for therapeutic intervention. A unique set of pathways is associated with immune exclusion and ICI resistance in AM. These data may inform immunotherapy combinations for immediate clinical translation.

The PD-1- and LAG-3-targeting bispecific molecule tebotelimab in solid tumors and hematologic cancers: a phase 1 trial.

Tebotelimab, a bispecific PD-1×LAG-3 DART molecule that blocks both PD-1 and LAG-3, was investigated for clinical safety and activity in a phase 1 dose-escalation and cohort-expansion clinical trial in patients with solid tumors or hematologic malignancies and disease progression on previous treatment. Primary endpoints were safety and maximum tolerated dose of tebotelimab when administered as a single agent (n = 269) or in combination with the anti-HER2 antibody margetuximab (n = 84). Secondary endpoints included anti-tumor activity. In patients with advanced cancer treated with tebotelimab monotherapy, 68% (184/269) experienced treatment-related adverse events (TRAEs; 22% were grade ≥3). No maximum tolerated dose was defined; the recommended phase 2 dose (RP2D) was 600 mg once every 2 weeks. There were tumor decreases in 34% (59/172) of response-evaluable patients in the dose-escalation cohorts, with objective responses in multiple solid tumor types, including PD-1-refractory disease, and in LAG-3+ non-Hodgkin lymphomas, including CAR-T refractory disease. To enhance potential anti-tumor responses, we tested margetuximab plus tebotelimab. In patients with HER2+ tumors treated with tebotelimab plus margetuximab, 74% (62/84) had TRAEs (17% were grade ≥3). The RP2D was 600 mg once every 3 weeks. The confirmed objective response rate in these patients was 19% (14/72), including responses in patients typically not responsive to anti-HER2/anti-PD-1 combination therapy. ClinicalTrials.gov identifier: NCT03219268 .

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of melanoma, version 3.0.

Since the first approval for immune checkpoint inhibitors (ICIs) for the treatment of cutaneous melanoma more than a decade ago, immunotherapy has completely transformed the treatment landscape of this chemotherapy-resistant disease. Combination regimens including ICIs directed against programmed cell death protein 1 (PD-1) with anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) agents or, more recently, anti-lymphocyte-activation gene 3 (LAG-3) agents, have gained regulatory approvals for the treatment of metastatic cutaneous melanoma, with long-term follow-up data suggesting the possibility of cure for some patients with advanced disease. In the resectable setting, adjuvant ICIs prolong recurrence-free survival, and neoadjuvant strategies are an active area of investigation. Other immunotherapy strategies, such as oncolytic virotherapy for injectable cutaneous melanoma and bispecific T-cell engager therapy for HLA-A*02:01 genotype-positive uveal melanoma, are also available to patients. Despite the remarkable efficacy of these regimens for many patients with cutaneous melanoma, traditional immunotherapy biomarkers (ie, programmed death-ligand 1 expression, tumor mutational burden, T-cell infiltrate and/or microsatellite stability) have failed to reliably predict response. Furthermore, ICIs are associated with unique toxicity profiles, particularly for the highly active combination of anti-PD-1 plus anti-CTLA-4 agents. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to develop this clinical practice guideline on immunotherapy for the treatment of melanoma, including rare subtypes of the disease (eg, uveal, mucosal), with the goal of improving patient care by providing guidance to the oncology community. Drawing from published data and clinical experience, the Expert Panel developed evidence- and consensus-based recommendations for healthcare professionals using immunotherapy to treat melanoma, with topics including therapy selection in the advanced and perioperative settings, intratumoral immunotherapy, when to use immunotherapy for patients with BRAFV600-mutated disease, management of patients with brain metastases, evaluation of treatment response, special patient populations, patient education, quality of life, and survivorship, among others.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of melanoma, version 3.0

Since the first approval for immune checkpoint inhibitors (ICIs) for the treatment of cutaneous melanoma more than a decade ago, immunotherapy has completely transformed the treatment landscape of this chemotherapy-resistant disease. Combination regimens including ICIs directed against programmed cell death protein 1 (PD-1) with anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) agents or, more recently, anti-lymphocyte-activation gene 3 (LAG-3) agents, have gained regulatory approvals for the treatment of metastatic cutaneous melanoma, with long-term follow-up data suggesting the possibility of cure for some patients with advanced disease. In the resectable setting, adjuvant ICIs prolong recurrence-free survival, and neoadjuvant strategies are an active area of investigation. Other immunotherapy strategies, such as oncolytic virotherapy for injectable cutaneous melanoma and bispecific T-cell engager therapy for HLA-A*02:01 genotype-positive uveal melanoma, are also available to patients. Despite the remarkable efficacy of these regimens for many patients with cutaneous melanoma, traditional immunotherapy biomarkers (ie, programmed death-ligand 1 expression, tumor mutational burden, T-cell infiltrate and/or microsatellite stability) have failed to reliably predict response. Furthermore, ICIs are associated with unique toxicity profiles, particularly for the highly active combination of anti-PD-1 plus anti-CTLA-4 agents. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to develop this clinical practice guideline on immunotherapy for the treatment of melanoma, including rare subtypes of the disease (eg, uveal, mucosal), with the goal of improving patient care by providing guidance to the oncology community. Drawing from published data and clinical experience, the Expert Panel developed evidence- and consensus-based recommendations for healthcare professionals using immunotherapy to treat melanoma, with topics including therapy selection in the advanced and perioperative settings, intratumoral immunotherapy, when to use immunotherapy for patients with BRAFV600- mutated disease, management of patients with brain metastases, evaluation of treatment response, special patient populations, patient education, quality of life, and survivorship, among others.

Identification of tumor-intrinsic drivers of immune exclusion in acral melanoma.

Background: Acral melanoma (AM) has distinct characteristics as compared to cutaneous melanoma and exhibits poor response to immune checkpoint inhibitors (ICI). Tumor-intrinsic mechanisms of immune exclusion have been identified in many cancers but less studied in AM. Methods: We characterized clinically annotated tumors from patients diagnosed with AM at our institution in correlation with ICI response using whole transcriptome RNAseq, whole exome sequencing, CD8 immunohistochemistry, and multispectral immunofluorescence imaging. A defined interferon-γ-associated T cell-inflamed gene signature was used to categorize tumors into non-T cell-inflamed and T cell-inflamed phenotypes. In combination with AM tumors from two published studies, we systematically assessed the immune landscape of AM and detected differential gene expression and pathway activation in a non-T cell-inflamed tumor microenvironment (TME). Two single-cell(sc) RNAseq AM cohorts and 11 bulk RNAseq cohorts of various tumor types were used for independent validation on pathways associated with lack of ICI response. In total, 892 specimens were included in this study. Results: 72.5% of AM tumors showed low expression of the T cell-inflamed gene signature, with 23.9% of total tumors categorized as the non-T cell-inflamed phenotype. Patients of low CD3 + CD8 + PD1 + intratumoral T cell density showed poor prognosis. We identified 11 oncogenic pathways significantly upregulated in non-T cell-inflamed relative to T cell-inflamed TME shared across all three acral cohorts (MYC, HGF, MITF, VEGF, EGFR, SP1, ERBB2, TFEB, SREBF1, SOX2, and CCND1). scRNAseq analysis revealed that tumor cell-expressing pathway scores were significantly higher in low vs high T cell-infiltrated AM tumors. We further demonstrated that the 11 pathways were enriched in ICI non-responders compared to responders across cancers, including acral melanoma, cutaneous melanoma, triple-negative breast cancer, and non-small cell lung cancer. Pathway activation was associated with low expression of interferon stimulated genes, suggesting suppression of antigen presentation. Across the 11 pathways, fatty acid synthase and CXCL8 were unifying downstream target molecules suggesting potential nodes for therapeutic intervention. Conclusions: A unique set of pathways is associated with immune exclusion and ICI resistance in AM. These data may inform immunotherapy combinations for immediate clinical translation.