Immune checkpoint inhibitors (ICIs) have improved cancer outcomes; however, many patients fail to respond, highlighting the need for novel targets. HVEM (Herpes Virus Entry Mediator) is an immune regulator with both inhibitory and stimulatory functions, making it a promising therapeutic candidate. We have developed Anti-4CB1, a fully human monoclonal antibody (mAb) that selectively blocks HVEM interactions with BTLA and CD160. Its activity was evaluated in-vitro using human tumor-infiltrating lymphocytes (TILs), peripheral blood mononuclear cells (PBMCs), and M1 macrophages, as well as in ex-vivo patient-derived tumor samples and in-vivo transgenic and humanized mouse models. HVEM expression was also assessed in serum and tumor tissues. Anti-4CB1 enhanced T-cell activation and cytotoxicity, evidenced by increased tumor cell killing, upregulation of activation markers (41BB, CD107a), and elevated IFNγ and TNFα secretion. It also promoted macrophage-mediated phagocytosis. In ex-vivo analyses of 49 patient-derived tumor samples, Anti-4CB1 increased cytotoxicity in 28.5% of cases, including samples unresponsive to anti-PD1. In-vivo, Anti-4CB1 demonstrated significant anti-tumor activity as monotherapy and showed enhanced efficacy in combination with anti-PD1. Additionally, higher tumor HVEM expression correlated with improved response to checkpoint blockade, while elevated soluble HVEM levels were associated with reduced responsiveness to Anti-HVEM. Anti-4CB1 enhances both adaptive and innate anti-tumor immunity and shows activity in anti-PD1 resistant settings. These findings support its potential as a novel therapeutic agent and suggest HVEM as a predictive biomarker for immunotherapy response.

OBJECTIVE:Vulvar and vaginal melanoma are rare gynecologic malignancies with aggressive clinical behavior and poor prognosis. Due to their low incidence and exclusion from most clinical trials, treatment decisions are often extrapolated from cutaneous melanoma data. This study aims to provide real-world insights into the clinical course and outcomes of vulvar and vaginal melanoma in the context of modern systemic therapy. METHODS:We retrospectively analyzed 39 patients with vulvar or vaginal melanoma treated at a single tertiary cancer center between 2011 and 2023. Clinical and pathologic data, including tumor site, stage, treatment modalities, and outcomes, were collected. Systemic therapy regimens included anti-PD-1 antibody monotherapy (either pembrolizumab or nivolumab), anti-PD-1 + anti-CTLA4 combination therapy (ipilimumab and nivolumab), and chemotherapy combined with interleukin-2. Progression-free survival and overall survival were evaluated. RESULTS:Patients frequently presented with locally advanced disease. High rates of multifocality, positive margins, and repeated local recurrence were observed, particularly in vulvar primaries. Among those treated for advanced disease (n = 28), combination immunotherapy yielded the most durable responses. Vulvar melanoma was associated with longer progression-free survival and overall survival compared with vaginal melanoma (median progression-free survival: 33 vs. 5 mo, HR = 3.8; median overall survival: 42 vs. 10 mo, HR = 7.8). CONCLUSIONS:Vulvar and vaginal melanoma present unique diagnostic and therapeutic challenges in gynecologic oncology. Site-specific prognosis and distinct response patterns to immunotherapy underscore the importance of individualized management strategies and multidisciplinary coordination in this rare population.

BACKGROUND:Sentinel lymph node biopsy (SLNB) is standard for staging high-risk melanoma, but current mapping provides limited spatial guidance. This pilot study assessed whether augmented reality (AR) projected 3D models can improve sentinel node localization compared with the gamma probe. METHODS:In this prospective study, 10 melanoma patients undergoing SLNB at Sheba Medical Center had preoperative sentinel lymphoscintigraphy using SPECT/CT imaging segmented to generate patient-specific 3D models. Models were projected onto the patient via an AR headset before incision. Localization accuracy was measured as the deviation (mm) between AR3D-identified and gamma probe-identified sentinel lymph node positions. RESULTS:Ten patients were enrolled in this pilot study. The median age was 71 years (range 30-77). Primary tumor sites included upper limb (n = 5), trunk (n = 3), Lower Limb (n = 1), and Head and Neck (n = 1). The median Breslow thickness was 1.1 mm (range 0.8-24 mm), with ulceration in 2 cases. Model generation was successful in all patients, with each model projected onto the patient using the AR headset and evaluated by the surgeon prior to incision. The median deviation between AR3D model and the gamma probe localization was 12 mm (range 0-40 mm), with 43% of cases ≤ 10 mm. No AR-related complications occurred. CONCLUSIONS:AR-based 3D modelling was feasible and safe for SLNB localization in melanoma. Although accuracy varied, in nearly half of the cases, AR3D model was within 10 mm of the gamma probe detection. These preliminary results supported further refinement of the technique and evaluation in larger, multicenter trials.

Primers and Antibodies used in this paper.

Melanoma has important burden in older populations due to high incidence and aggressive biology. The emergence of immunotherapy with immune checkpoint inhibitors and targeted therapy (BRAF/MEK inhibitors) significantly improved melanoma prognosis. Currently, the body of knowledge on the efficacy and tolerability of these treatments in geriatric patients is primarily based on the results outside of clinical trials since the majority of clinical studies do not include older patients. We present a comprehensive narrative review of published data regarding efficacy and safety of therapeutic modalities using immune checkpoint inhibitors in patients age 65–75 years and >75 years: the anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) inhibitor (ipilimumab), the anti-programmed death-ligand 1 (PD-1) inhibitors (nivolumab and pembrolizumab), and the lymphocyte activation gene-3 (LAG-3) inhibitor (relatlimab). We carefully address difficulties in multi-disciplinary clinical decision-making in care of older melanoma patients. Although many older patients may not be offered immunotherapy, the available evidence indicates that immunotherapy is equally beneficial in the older patients and does not have higher incidence of adverse events in this group of patients compared to younger population.

Supplementary Figure Legends

Similarity between TIL ACT and PD-1 blockade response mechanism. Related to Figure S1.

Abstract Background: Pembrolizumab (pembro) monotherapy demonstrated clinically meaningful antitumor activity for both locally advanced (LA) and recurrent or metastatic (R/M) cutaneous squamous cell carcinoma (cSCC) in the phase 2 KEYNOTE-629 trial (NCT03284424). cSCC has high immunogenicity driven by a high tumor mutational burden and it is of interest to determine if the 18-gene T-cell inflamed gene expression profile (TcellinfGEP) and a set of other signatures relevant to the tumor microenvironment are associated with response to treatment. This retrospective analysis aimed to evaluate the association between GEP signatures and clinical outcomes in patients (pts) treated with pembro in KEYNOTE-629. Methods: Pts with histologically confirmed LA or R/M cSCC, measurable disease per RECIST v1.1, ECOG PS 0 or 1 received pembro 200 mg IV Q3W ≤35 cycles. Association between TcellinfGEP by RNAseq with clinical response (objective response rate [ORR], progression-free survival [PFS], and overall survival [OS]) to pembro, and association between a set of additional consensus signatures with clinical response to pembro adjusted for TcellinfGEP were evaluated. Significance of GEP signatures was prespecified at 0.05 for 1-sided P values from logistic (ORR) and Cox proportional hazard regression (PFS, OS) adjusted for ECOG PS. Additional assessments included TcellinfGEP AUC or Harrell’s C-index in predicting response to pembro. Results: Of 159 pts, 143 (n = 52, LA cSCC; n = 91, R/M cSCC) had RNAseq samples available for analysis. Of 143 pts, 33.6 % had a TcellinfGEP <1st tertile and 66.4% had a TcellinfGEP ≥1st tertile. TcellinfGEP was significantly associated with improved ORR (P = 0.040) but not PFS (P = 0.087) or OS (P = 0.709). None of the 10 other consensus signatures were significantly associated with clinical outcomes after adjusting for TcellinfGEP and multiplicity (P > 0.05). AUC of TcellinfGEP was moderately predictive of ORR (0.61, 95% CI, 0.51-0.70). Harrell’s C-index of TcellinfGEP was moderately predictive of PFS (0.57, 95% CI 0.51-0.63), and duration of response (0.56, 95% CI 0.38-0.73), but not predictive of OS (0.50, 95% CI 0.42-0.57). Median PFS (95% CI) was 4.1 mo (1.4-9.8) for the TcellinfGEP <1st tertile subgroup and 8.5 mo (5.5-21.0) for TcellinfGEP ≥1st tertile subgroup. Median OS (95% CI) for the TcellinfGEP <1st tertile subgroup was 25.1 mo (11.4-NR) and 21.0 mo (15.8-29.8) for the TcellinfGEP ≥1st tertile subgroup. Conclusions: In this retrospective analysis of KEYNOTE-629, Tcellinf GEP was associated with tumor objective response to pembro, but was not clearly associated with longer survival in pts with LA or R/M cSCC treated with pembro. While definitive conclusions require more analyses, these findings provide additional support for TcellinfGEP as a predictive biomarker for cSCC. Citation Format: Åse Bratland, Jean-Jacques Grob, Eva Munoz Couselo, Laurent Mortier, Ralf Gutzmer, Osama Roshdy, Rene Mendoza Gonzalez, Jacob Schachter, Ana M. Arance Fernandez, Florent Grange, Nicolas Meyer, Abhishek J. Joshi, Salem Billan, Judong Shen, Razvan Cristescu, Michael Nebozhyn, Andrey Loboda, Jason Sparkowski, Burak Gumuscu, Jianda Yuan, Brett Hughes. Association of gene expression profiles and clinical outcomes in patients with locally advanced or recurrent/metastatic cutaneous squamous cell carcinoma treated with pembrolizumab in KEYNOTE-629 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT207.

9500 Background: Dabrafenib plus trametinib, a standard-of care adjuvant treatment for patients with BRAF-mutated AJCC-stage III melanoma, has significantly improved the primary endpoint, relapse-free survival (RFS). Further to published interim assessments, we present updated and final results for RFS, distant-metastasis-free survival (DMFS) and overall survival (OS). Methods: In the COMBI-AD phase 3 study, patients received dabrafenib (150 mg BD) plus trametinib (2 mg OD; n=438) or matching placebos (n=432). Treatment continued for up to 12 months or until disease relapse, unacceptable toxicity, withdrawal of consent, or death. OS, RFS, and DMFS were summarized using Kaplan–Meier estimates. OS was compared between study arms using stratified log-rank test. Hazard ratio (HR) was calculated using Pike estimator. Safety data were summarized descriptively. Results: At final analysis, median duration of follow up was 100.0 months in the treatment arm and 82.5 months in the placebo arm. Median OS was not attained in the two arms (HR: 0.80; 95% CI: 0.62, 1.01; P=0.063). Consistent OS benefits were seen across most prespecified subgroups including patients with BRAFV600E mutation (n=397; HR: 0.75; 95% CI: 0.58, 0.96). Estimated RFS (HR: 0.52; 95% CI: 0.43, 0.63) and DMFS (HR: 0.56; 95% CI: 0.44, 0.71) favored the dabrafenib plus trametinib arm. In both arms, patients received salvage immunotherapies (29% each) and targeted therapy (21% vs. 37% for treatment and placebo arms, respectively). Safety profile was consistent with previous reports. Conclusions: COMBI-AD presents the longest follow-up data (over 10 years) in adjuvant treatment of stage III melanoma in the modern era. OS was improved with dabrafenib plus trametinib over placebo for adjuvant treatment of stage III melanoma with a 20% risk reduction for death. However, this difference was not statistically significant. Consistent with published results at 3 and 5 years, RFS and DMFS were more favorable in the treatment vs. placebo arm. Clinical trial information: NCT01682083 . [Table: see text]

9554 Background: Pembro monotherapy is approved in certain countries, including the US, for treatment of LA or R/M cSCC based on results from the open-label phase 2 KEYNOTE-629 trial (NCT03284424). Promising antitumor activity was demonstrated with pembro in both the LA and R/M cohorts. ORR (95% CI) was 50.0% (36.1-63.9; 16.7% CRs) in the LA cohort and 35.2% (26.2-45.2; 10.5% CRs) in the R/M cohort. We present data from KEYNOTE-629 with an additional follow-up of 38 mo for LA and R/M cohorts. Methods: Adults with histologically confirmed LA or R/M cSCC, measurable disease per RECIST v1.1 by blinded independent central review (BICR), and ECOG PS 0 or 1 received pembro 200 mg IV every 3 weeks for up to 35 cycles (~2 years). The primary end point was ORR per RECIST v1.1 by BICR. Secondary end points were DOR, DCR (CR + PR + SD ≥12 wks), and PFS per RECIST v1.1 by BICR; OS; and safety. End points were analyzed in pts who received ≥1 dose of pembro. Results: A total of 159 pts were treated with pembro (LA, n = 54; R/M, n = 105). As of September 13, 2023, 33 pts (20.8%) completed treatment and 126 pts (79.2%) discontinued treatment. Median (range) follow-up was 52.4 mo (47.6-56.9) for the LA cohort, 64.7 mo (62.1-69.5) for the R/M cohort, and 63.1 mo (47.6-69.5) in the total population. ORR and DCR are shown in the table. Median DOR (range) was 47.2 mo (1.0+ to 49.9+) in the LA cohort, not reached (NR; 2.7 to 64.2+ mo) in the R/M cohort, and 52.5 mo (1.0+ to 64.2+) in the total population; the proportion of responders with responses ≥12 mo by Kaplan-Meier estimate were 84.8%, 77.8%, and 80.7%, respectively. Median (95% CI) PFS was 14.4 mo (5.5-43.6) in the LA cohort, 5.7 mo (3.1-8.5) in the R/M cohort, and 8.0 mo (5.3-14.4) in the total population; 12-mo rates were 56.7%, 37.3%, and 43.7%, respectively. Median (95% CI) OS was NR (33.3-NR) in the LA cohort, 23.8 mo (13.4-30.9) in the R/M cohort, and 29.8 mo (20.0-42.8) in the total population; 36-mo rates were 62.0%, 39.5%, and 47.0%, respectively. Grade 3-5 treatment-related AEs occurred in 11.3% of pts, and grade 3-5 immune-mediated AEs and infusion reactions occurred in 8.8% of pts. Two pts (1.3%) died due to a treatment-related AE (colitis, cranial nerve disorder). Conclusions: With a median follow-up of more than 5 years, pembro continued to show durable responses in pts with LA or R/M cSCC. No new safety signals were observed. Results from this study continue to support the use of pembro in this pt population. Clinical trial information: NCT03284424 . [Table: see text]

Background Ameloblastoma is a rare odontogenic neoplasm frequently located in the mandible. Standard treatment involves radical bone resection and immediate reconstruction, causing functional, aesthetic, and psychological impairments. The BRAF V600E mutation is present in approximately 80% of mandible ameloblastomas, and BRAF inhibitors have demonstrated sustained responses in unresectable cases. Methods We identified ameloblastoma patients planned for ablative surgery and screened them for BRAF V600E mutation. Neoadjuvant BRAF inhibitors were offered to facilitate jaw preservation surgery. Retrospective data collection encompassed treatment regimens, tolerability, tumor response, and conversion to mandible preservation surgery. Results Between 2017 and 2022, a total of 11 patients received dabrafenib (n = 6) or dabrafenib with trametinib (n = 5). The median age was 19 (range = 10-83) years. Median treatment duration was 10 (range = 3-20) months. All (100%) patients achieved a radiological response. Ten (91%) patients successfully converted to mandible preservation surgery with residual tumor enucleation. One patient attained complete radiological response, and surgery was not performed. Among the 10 surgically treated patients, all exhibited a pathological response, with 4 achieving near complete response and 6 partial response. At a median follow-up of 14 (range = 7-37) months after surgery, 1 case of recurrence was observed. Grade 1-2 adverse effects were reported in 8 (73%) patients, with a single case of grade 3 (hepatitis). Dose modification was necessary for 3 patients, and 4 experienced treatment interruptions, while 1 patient permanently discontinued therapy. Conclusions Neoadjuvant BRAF inhibition may offer a safe and effective strategy for organ preservation in mandible ameloblastoma treatment.

9566 Background: Several studies have demonstrated that patients who experience irAE as a result of ICI treatment, exhibit significantly improved outcomes compared to patients without toxicity. However, data regarding the impact of specific irAE is currently lacking. Methods: This is a real world single-site cohort of advanced melanoma patients who were treated with ICI as first line between 2014 and 2020. This study explores the effects of specific irAE on treatment efficacy. Results: Three hundred and ninety-five (395) patients were treated with either monotherapy anti PD-1 (65.4%), combination ICI (24.3%), or anti CTLA-4 (10.3%). Median age was 68 years (12-99y), and 57% were male. The median follow up was 24.5m. Any-grade irAEs were seen in 72% (n = 299), and 26% experienced high-grade irAE (n = 104). The most frequent irAE were dermatologic (n = 110, 27.8%), vitiligo (n = 48, 12.1%), rheumatologic (n = 68, 17.2%), gastro-intestinal (n = 66, 16.7%), and endocrine (n = 61, 15.4%). The development of irAE was associated with a significantly longer median PFS (19.3m vs 4.5m; HR 0.46, p < 0.001) and median OS (55m vs 16.9m; HR 0.44, p < 0.001). Specific irAE that were significantly associated with survival benefic were rheumatologic (HR 0.34 for PFS, p < 0.001; HR 0.38 for OS, p < 0.001), dermatologic (HR 0.58 for PFS, p < 0.001; HR 0.54 for OS, p = 0.001), vitiligo (HR 0.30 for PFS, p < 0.001; HR 0.29 for OS, p < 0.001) and endocrine (HR 0.6 for PFS, p = 0.01; HR 0.52 for OS, p < 0.001). After adjustment for ECOG performance status, LDH level, type of ICI protocol and M-substage - the rheumatologic, dermatologic and vitiligo irAE remained significant on multivariate analysis for both PFS and OS. Conclusions: The development of rheumatologic, vitiligo and other dermatologic irAE during ICI treatment, is correlated with a noteworthy survival advantage. These irAE may reflect a hyper-activated immune response and thus can serve as meaningful clinical biomarkers.

Background The 5-year results of this trial showed that adjuvant therapy with dabrafenib plus trametinib resulted in longer relapse-free survival and distant metastasis-free survival than placebo among patients with BRAF V600-mutated stage III melanoma. Longer-term data were needed, including data regarding overall survival. Methods We randomly assigned 870 patients with resected stage III melanoma with BRAF V600 mutations to receive 12 months of dabrafenib (150 mg twice daily) plus trametinib (2 mg once daily) or two matched placebos. Here, we report the final results of this trial, including results for overall survival, melanoma-specific survival, relapse-free survival, and distant metastasis-free survival. Results The median duration of follow-up was 8.33 years for dabrafenib plus trametinib and 6.87 years for placebo. Kaplan-Meier estimates for overall survival favored dabrafenib plus trametinib over placebo, although the benefit was not significant (hazard ratio for death, 0.80; 95% confidence interval [CI], 0.62 to 1.01; P=0.06 by stratified log-rank test). A consistent survival benefit was seen across several prespecified subgroups, including the 792 patients with melanoma with a BRAF V600E mutation (hazard ratio for death, 0.75; 95% CI, 0.58 to 0.96). Relapse-free survival favored dabrafenib plus trametinib over placebo (hazard ratio for relapse or death, 0.52; 95% CI, 0.43 to 0.63), as did distant metastasis-free survival (hazard ratio for distant metastasis or death, 0.56; 95% CI, 0.44 to 0.71). No new safety signals were reported, a finding consistent with previous trial reports. Conclusions After nearly 10 years of follow-up, adjuvant therapy with dabrafenib plus trametinib was associated with better relapse-free survival and distant metastasis-free survival than placebo among patients with resected stage III melanoma. The analysis of overall survival showed that the risk of death was 20% lower with combination therapy than with placebo, but the benefit was not significant. Among patients with melanoma with a BRAF V600E mutation, the results suggest that the risk of death was 25% lower with combination therapy.

PDF file - 43K, the objective responses of individual patients to various types of immunotherapies.