Utility of next-generation sequencing in the diagnosis of metastatic melanoma: A case report

During routine dermatologic examination, a 77-year-old male was noted to have a firm blue subcutaneous nodule on his right lateral upper back. His past medical history included metastatic melanoma of unknown primary involving right and left axillary lymph nodes, treated with ipilimumab/nivolumab with complete response, and subsequent primary uveal melanoma. The subcutaneous nodule was located near his previous right axillary scar for metastatic melanoma. Excision of the nodule showed a plexiform neoplasm involving mid and deep dermis composed of spindle and epithelioid atypical cells admixed with numerous melanophages. Central necrosis was present. Immunohistochemical studies revealed the tumor cells to be diffusely positive for HMB45, with retained expression of BAP1 and p16. The tumor cells were negative for PRAME, nuclear expression of β-catenin, LEF1, and BRAF V600E. Molecular studies demonstrated BAP1 and GNA11 somatic mutations, a profile different from that exhibited by his prior melanoma. Collectively, these data were interpreted as a metastasis from uveal melanoma and not a recurrence of his metastatic likely cutaneous melanoma after complete response to immunotherapy. This case emphasizes the importance of molecular studies for definitive diagnosis in challenging clinical situations, especially when there is discordance among histopathological, immunohistochemical, and molecular studies. Integration of clinical, histopathological, and molecular features is warranted.

Imipridones inhibit tumor growth and improve survival in an orthotopic liver metastasis mouse model of human uveal melanoma

Purpose

Uveal melanoma (UM) is a highly aggressive disease with very few treatment options. We previously demonstrated that mUM is characterized by high oxidative phosphorylation (OXPHOS). Here we tested the anti-tumor, signaling and metabolic effects of imipridones, CLPP activators which reduce OXPHOS indirectly and have demonstrated safety in patients.

Experimental Design

We assessed CLPP expression in UM patient samples. We tested the effects of imipridones (ONC201, ONC212) on the growth, survival, signaling and metabolism of UM cell lines in vitro, and for therapeutic effects in vivo in UM liver metastasis models.

Results

CLPP expression was confirmed in primary and mUM patient samples. ONC201/212 treatment of UM cell lines in vitro decreased OXPHOS effectors, inhibited cell growth and migration, and induced apoptosis. ONC212 increased metabolic stress and apoptotic pathways, inhibited amino acid metabolism, and induced cell death-related lipids. ONC212 also decreased tumor burden and increased survival in vivo in two UM liver metastasis models.

Conclusion

Imipridones are a promising strategy for further testing and development in mUM.

Proceedings from the Melanoma Research Foundation Mucosal Melanoma Meeting (December 16, 2022, New York, USA)

Mucosal melanoma remains a rare cancer with high mortality and a paucity of therapeutic options. This is due in significant part to its low incidence leading to limited patient access to expert care and downstream clinical/basic science data for research interrogation. Clinical challenges such as delayed and at times inaccurate diagnoses, and lack of consensus tumor staging have added to the suboptimal outcomes for these patients. Clinical trials, while promising, have been difficult to activate and accrue. While individual institutions and investigators have attempted to seek solutions to such problems, international, national, and local partnership may provide the keys to more efficient and innovative paths forward. Furthermore, a mucosal melanoma coalition would provide a potential network for patients and caregivers to seek expert opinion and advice. The Melanoma Research Foundation Mucosal Melanoma Meeting (December 16, 2022, New York, USA) highlighted the current clinical challenges faced by patients, providers, and scientists, identified current and future clinical trial investigations in this rare disease space, and aimed to increase national and international collaboration among the mucosal melanoma community in an effort to improve patient outcomes. The included proceedings highlight the clinical challenges of mucosal melanoma, global clinical trial experience, basic science advances in mucosal melanoma, and future directions, including the creation of shared rare tumor registries and enhanced collaborations.

Ipilimumab with or without nivolumab in PD-1 or PD-L1 blockade refractory metastatic melanoma: a randomized phase 2 trial

In this randomized phase 2 trial, blockade of cytotoxic T-lymphocyte protein 4 (CTLA-4) with continuation of programmed death protein 1 (PD-1) blockade in patients with metastatic melanoma who had received front-line anti-PD-1 or therapy against programmed cell death 1 ligand 1 and whose tumors progressed was tested in comparison with CTLA-4 blockade alone. Ninety-two eligible patients were randomly assigned in a 3:1 ratio to receive the combination of ipilimumab and nivolumab, or ipilimumab alone. The primary endpoint was progression-free survival. Secondary endpoints included the difference in CD8 T cell infiltrate among responding and nonresponding tumors, objective response rate, overall survival and toxicity. The combination of nivolumab and ipilimumab resulted in a statistically significant improvement in progression-free survival over ipilimumab (hazard ratio = 0.63, 90% confidence interval (CI) = 0.41-0.97, one-sided P = 0.04). Objective response rates were 28% (90% CI = 19-38%) and 9% (90% CI = 2-25%), respectively (one-sided P = 0.05). Grade 3 or higher treatment-related adverse events occurred in 57% and 35% of patients, respectively, which is consistent with the known toxicity profile of these regimens. The change in intratumoral CD8 T cell density observed in the present analysis did not reach statistical significance to support the formal hypothesis tested as a secondary endpoint. In conclusion, primary resistance to PD-1 blockade therapy can be reversed in some patients with the combination of CTLA-4 and PD-1 blockade. Clinicaltrials.gov identifier: NCT03033576 .

Safety and Efficacy of Immune Checkpoint Inhibitors in Patients with Cancer and Viral Hepatitis: The MD Anderson Cancer Center Experience

BACKGROUND

Despite the clinical benefit of immune checkpoint inhibitors (ICIs), patients with a viral hepatitis have been excluded from clinical trials because of safety concerns. The purpose of this study was to determine the incidence rate of adverse events (AEs) in patients with viral hepatitis who received ICIs for cancer treatment.

MATERIALS AND METHODS

We conducted a retrospective study in patients with cancer and concurrent hepatitis B or C, who had undergone treatment with ICI at MD Anderson Cancer Center from January 1, 2010 to December 31, 2019.

RESULTS

Of the 1076 patients screened, we identified 33 with concurrent hepatitis. All 10 patients with HBV underwent concomitant antiviral therapy during ICI treatment. Sixteen of the 23 patients with HCV received it before the initiation of ICI. The median follow-up time was 33 months (95% CI, 23-45) and the median duration of ICI therapy was 3 months (IQR, 1.9-6.6). Of the 33 patients, 12 (39%) experienced irAEs (immune-related adverse events) of any grade, with 2 (6%) having grade 3 or higher. None of the patients developed hepatitis toxicities.

CONCLUSION

ICIs may be a therapeutic option with an acceptable safety profile in patients with cancer and advanced liver disease.

T-cell receptor beta variable gene polymorphism predicts immune-related adverse events during checkpoint blockade immunotherapy

BACKGROUND

Immune checkpoint inhibitors have revolutionized cancer treatment. However, they are associated with a unique spectrum of side effects, called immune-related adverse events (irAEs), which can cause significant morbidity and quickly progress to severe or life-threatening events if not treated promptly. Identifying predictive biomarkers for irAEs before immunotherapy initiation is therefore a critical area of research. Polymorphisms within the T-cell receptor beta (TCRB) variable (TRBV) gene have been implicated in autoimmune disease and may be mechanistically linked to irAEs. However, the repetitive nature of the TCRB locus and incomplete genome assembly has hampered the evaluation of TRBV polymorphisms in the past.

PATIENTS AND METHODS

We used a novel method for long-amplicon next generation sequencing of rearranged TCRB chains from peripheral blood total RNA to evaluate the link between TRBV polymorphisms and irAEs in patients treated with immunotherapy for cancer. We employed multiplex PCR to create amplicons spanning the three beta chain complementarity-determining regions (CDR) regions to enable detection of polymorphism within the germline-encoded framework and CDR1 and CDR2 regions in addition to CDR3 profiling. Resultant amplicons were sequenced via the Ion Torrent and TRBV allele profiles constructed for each individual was correlated with irAE annotations to identify haplotypes associated with severe irAEs (≥ grade 3).

RESULTS

Our study included 81 patients who had irAEs when treated with immunotherapy for cancer. By using principal component analysis of the 81 TRBV allele profiles followed by k-means clustering, we identified six major TRBV haplotypes. Strikingly, we found that one-third of this cohort possessed a TRBV allele haplotype that appeared to be protective against severe irAEs.

CONCLUSION

The data suggest that long-amplicon TCRB repertoire sequencing can potentially identify TRBV haplotype groups that correlate with the risk of severe irAEs. Germline-encoded TRBV polymorphisms may serve as a predictive biomarker of severe irAEs.

Presence of Circulating Tumor Cells Predates Imaging Detection of Relapse in Patients with Stage III Melanoma

Stage III melanoma includes nodal metastasis or in-transit disease. Five-year survival rates vary between 32% and 93%. The identification of high-risk patients is important for clinical decision making. We demonstrated previously that ≥1 circulating tumor cells (CTCs) at baseline was associated with recurrence. In this study, we investigated how frequently CTCs were identified prior to radiologically detected recurrence. Stage III patients (n = 325) had imaging at baseline and q 3 months. Baseline and q 6-12 months blood draws (7.5 mL) were performed to identify CTCs up to 3.5 years from diagnosis. CTC assessment was performed using the immunomagnetic capture of CD146-positive cells and anti-MEL-PE. The presence of one or more CTCs was considered positive. We analyzed the cohort of patients with relapse confirmed by radiologic imaging. CTC collection dates were assessed to determine the lead time for CTC detection. CTC-negative patients were significantly less likely to relapse compared to patients positive for CTCs (p-value < 0.001). Within the 325-patient cohort, 143 patients (44%) had recurrence, with a median follow-up of 52 months from diagnosis. The cohort (n = 143) with positive imaging and CTC results revealed 76% of patients (108/143) had CTC+ results before the radiological identification of relapse. The median time between positive CTC and positive imaging was 9 months. CTCs were positive in >75% of patients prior to relapse at a median of 9 months before radiologic detection.

Abstract 3275: Combination of talimogene laherparepvec (T-VEC) with pembrolizumab (pembro) in advanced melanoma patients following progression on a prior PD-1 inhibitor: SWOG S1607

We hypothesize that a significant number of patients do not respond to PD-1/L1 blockade because there are no pre-existing tumor antigen-specific T-cells, and this can be addressed by combination therapy with an oncolytic virus such as T-VEC. S1607 is a single arm Phase 2 study of T-VEC plus pembro in patients with advanced melanoma after PD-1/L1 inhibitor progression. The primary endpoint is ORR by modified RECIST (progression at the first follow-up disease assessment had to be confirmed). Secondary endpoints include durable response rate (response ≥ 6 months), ORR in injected, non-visceral non-injected, and visceral lesions, PFS, OS and toxicity. In Cohort A patients must have at least one measurable visceral lesion; in Cohort B patients must not have any visceral lesions. Each cohort had an independent accrual goal with a 2-stage design. All received intratumoral T-VEC and pembro 200mg IV every 21 days. Tumor biopsy and research blood are taken at baseline and on Day 28 (both injected and non-injected lesions). Tumor assessments are performed every 12 weeks for up to 2 years. 38 evaluable patients were enrolled. As of July 26, 2022, the median follow up was 28 months. Treatment was well tolerated, with 5/38 (13%) grade 3 AE (no grade 4/5) including injection site reactions, lymphocyte count decrease, and hypoxia. Cohort A was closed after stage I (n=11) with no confirmed responses. In Cohort B (n=27), there were 7 confirmed responses (26%; 2 CR, 5 PR; this rejected H0: ORR = 10%, p=0.01). Clinical outcomes are summarized in Table 1. Baseline tumor mutational burden from 17 patients in Cohort B were not different between responder vs non-responders (p=0.96). Translational study is ongoing for pharmacodynamic confirmation. T-VEC plus pembro in melanoma patients who have progressed on prior anti-PD1/L1 therapy has efficacy in the subset of melanoma patients who have non-visceral metastases.

Table 1 Cohort A (Visceral) Cohort B(Non-Visceral) N (%; 95% CI) 11 27 Confirmed PR + CR 0 (0%; 0%-28%) 7 (26%; 11%-46%) Confirmed + Unconfirmed 1 (9%; 0%-41%) 9 (33%; 17%-54%) Durable response 0 (0%; 0%-28%) 4 (15%; 4%-34%) Median PFS in months 2.1 (0.7-5.5) 2.3 (1.9-6.2) INJECTED LESIONS 11 27 Confirmed PR + CR 0 (0%; 0%-28%) 6 (22%; 9%-42%) Confirmed + Unconfirmed, PR + CR 1 (9%; 0%-41%) 8 (30%; 14%-50%) NON-INJECTED, NON-VISCERAL LESIONS 8 19 Confirmed PR + CR 0 (0%; 0%-37%) 3 (16%; 3%-40%) Confirmed + Unconfirmed, PR + CR 0 (0%; 0%-37%) 5 (26%; 9%-51%) VISCERAL LESIONS 11 Confirmed PR + CR 0 (0%; 0%-28%) Confirmed + Unconfirmed, PR + CR 1 (9%; 0%-41%) ACQUIRED RESISTANCE 3 2 Confirmed PR + CR 0 (0%; 0%-71%) 2 (100%; 16%-100%) Confirmed + Unconfirmed, PR + CR 0 (0%; 0%-71%) 2 (100%; 16%-100%) Median PFS in months 2.1 (2.0-4.1) NR (8.0-∞) PRIMARY RESISTANCE 8 25 Confirmed PR + CR 0 (0%; 0%-37%) 5 (20%; 7%-41%) Confirmed + Unconfirmed, PR + CR 1 (13%; 0%-53%) 7 (28%; 12%-49%) Median PFS in months 1.8 (0.3-6.2) 2.1 (1.9-3.3)

Citation Format: Siwen Hu-Lieskovan, James Moon, John Hyngstrom, Katie M. Campbell, Gino K. In, Theodore F. Logan, Kari L. Kendra, Ding M. Wang, Douglas B. Johnson, Gary C. Doolittle, Alan Tan, Ann W. Silk, Kenneth F. Grossmann, Christopher W. Ryan, Sapna P. Patel, Shay Bellasea, Michael C. Wu, John M. Kirkwood, Helen X. Chen, Antoni Ribas. Combination of talimogene laherparepvec (T-VEC) with pembrolizumab (pembro) in advanced melanoma patients following progression on a prior PD-1 inhibitor: SWOG S1607 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3275.

Abstract 5881: PERIO-01: Initial safety experience and immunologic effects of a Class C TLR9 agonist using pressure- enabled drug delivery in a phase 1 trial of hepatic arterial infusion of SD-101 +/- checkpoint inhibition in metastatic uveal melanoma

Immune checkpoint inhibitors (ICI) have demonstrated limited success in patients with metastatic uveal melanoma (MUM) with liver involvement due to an immunosuppressive tumor microenvironment (TME) driven in part by myeloid-derived suppressor cells (MDSCs). Toll-like receptor-9 agonists (TLR-9A) have improved ICI response rates in cutaneous melanoma, but delivery challenges have limited their application for MUM. Hepatic arterial infusion (HAI) of TLR-9A using a pressure-enabled drug deliveryTM (PEDDTM) device has the potential to enhance responsiveness to ICI by optimizing delivery to intrahepatic tumors and reprogramming the TME, including elimination of MDSCs.PERIO-01 is an open-label first-in-human Phase 1 trial of SD-101 given by HAI using a PEDDTM in MUM (NCT04935229). The study consists of dose-escalation cohorts of single agent SD-101 alone and with ICI. SD-101 is delivered over 2 cycles, with 3 weekly doses per cycle. Research blood, tumor and normal liver biopsies are collected serially for correlative studies. At data cutoff, a total of 20 patients were enrolled, with 13 in the single agent dose escalation cohort (2, 4, and 8 mg) and 7 patients with SD-101 (2 mg) + nivolumab. The median age was 65.5 years with an equal gender distribution. Only 2 patients were treatment-naïve and the median number of liver metastases was 5.1. The average number of SD-101 infusions was 5.2. One patient in the combination cohort experienced a serious adverse event related to treatment - asymptomatic Grade 3 increase in liver enzymes. PEDDTM resulted in high drug levels in the liver (up to 2,340 ng/ml at 8mg) with only transient exposure in the periphery (&lt;4 hours) with one Grade 2 cytokine related syndrome adverse event. Dose-dependent increases in canonical TLR9-associated cytokines (IL-18, IFNγ, IP-10, and soluble CD25) was observed across the 2mg, 4mg, and 8mg single-agent dose levels. Concordant with predicted mechanism of action, PEDDTM HAI administered SD-101 resulted in decreases in liver monocytic MDSCs in 4 of 4 patients with available multiplex immunofluorescence data. NanoString analysis from three patients revealed increases in ISG15, IL-9, IFNα, and IL-2 transcripts and decreases in ARG1 and IDO transcripts, with increased scores for macrophages, activated CD8 T cells, Th1 cells, and Th1 activation. For patients who received 2mg SD-101 + ICI with available liquid biopsy data, 4 of 7 demonstrated decreases in circulating tumor cells and 3 of 5 showing ctDNA decreases after the first cycle. In this first-in-human experience, HAI of SD-101 via PEDDTM was well tolerated and associated with encouraging immunologic activity. Evidence of biologic activity with 2 mg of SD-101 with nivolumab is encouraging and patients are currently enrolling at higher SD-101 dose levels + ICI.

Citation Format: Sapna P. Patel, Cara Haymaker, Rahul A. Sheth, Joshua D. Kuban, Joshua Weintraub, Eric Wehrenberg-Klee, Paula Novelli, Carin Gonsalves, Robert Adamo, Virgina Honaker, Laura Timciuc, Tarin Hennegan, Juan C. Amador Molina, Dzifa Duose, Edwin R. Parras Cuenta, Anthony Lucci, Salyna Meas, Vanessa Sarli, Victor G. Prieto, Jason LaPorte, Ann-Marie Hulstine, Ashley Moody, Bryan Cox, David Geller, Diwakar Davar, Kamaneh Montazeri, Marlana Orloff, Steven C. Katz, Richard Carvajal. PERIO-01: Initial safety experience and immunologic effects of a Class C TLR9 agonist using pressure- enabled drug delivery in a phase 1 trial of hepatic arterial infusion of SD-101 +/- checkpoint inhibition in metastatic uveal melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5881.

Concurrent intrathecal and intravenous nivolumab in leptomeningeal disease: phase 1 trial interim results

There is a critical need for effective treatments for leptomeningeal disease (LMD). Here, we report the interim analysis results of an ongoing single-arm, first-in-human phase 1/1b study of concurrent intrathecal (IT) and intravenous (IV) nivolumab in patients with melanoma and LMD. The primary endpoints are determination of safety and the recommended IT nivolumab dose. The secondary endpoint is overall survival (OS). Patients are treated with IT nivolumab alone in cycle 1 and IV nivolumab is included in subsequent cycles. We treated 25 patients with metastatic melanoma using 5, 10, 20 and 50 mg of IT nivolumab. There were no dose-limiting toxicities at any dose level. The recommended IT dose of nivolumab is 50 mg (with IV nivolumab 240 mg) every 2 weeks. Median OS was 4.9 months, with 44% and 26% OS rates at 26 and 52 weeks, respectively. These initial results suggest that concurrent IT and IV nivolumab is safe and feasible with potential efficacy in patients with melanoma LMD, including in patients who had previously received anti-PD1 therapy. Accrual to the study continues, including in patients with lung cancer. ClinicalTrials.gov registration: NCT03025256 .

Neoadjuvant-Adjuvant or Adjuvant-Only Pembrolizumab in Advanced Melanoma

BACKGROUND

Whether pembrolizumab given both before surgery (neoadjuvant therapy) and after surgery (adjuvant therapy), as compared with pembrolizumab given as adjuvant therapy alone, would increase event-free survival among patients with resectable stage III or IV melanoma is unknown.

METHODS

In a phase 2 trial, we randomly assigned patients with clinically detectable, measurable stage IIIB to IVC melanoma that was amenable to surgical resection to three doses of neoadjuvant pembrolizumab, surgery, and 15 doses of adjuvant pembrolizumab (neoadjuvant-adjuvant group) or to surgery followed by pembrolizumab (200 mg intravenously every 3 weeks for a total of 18 doses) for approximately 1 year or until disease recurred or unacceptable toxic effects developed (adjuvant-only group). The primary end point was event-free survival in the intention-to-treat population. Events were defined as disease progression or toxic effects that precluded surgery; the inability to resect all gross disease; disease progression, surgical complications, or toxic effects of treatment that precluded the initiation of adjuvant therapy within 84 days after surgery; recurrence of melanoma after surgery; or death from any cause. Safety was also evaluated.

RESULTS

At a median follow-up of 14.7 months, the neoadjuvant-adjuvant group (154 patients) had significantly longer event-free survival than the adjuvant-only group (159 patients) (P = 0.004 by the log-rank test). In a landmark analysis, event-free survival at 2 years was 72% (95% confidence interval [CI], 64 to 80) in the neoadjuvant-adjuvant group and 49% (95% CI, 41 to 59) in the adjuvant-only group. The percentage of patients with treatment-related adverse events of grades 3 or higher during therapy was 12% in the neoadjuvant-adjuvant group and 14% in the adjuvant-only group.

CONCLUSIONS

Among patients with resectable stage III or IV melanoma, event-free survival was significantly longer among those who received pembrolizumab both before and after surgery than among those who received adjuvant pembrolizumab alone. No new toxic effects were identified. (Funded by the National Cancer Institute and Merck Sharp and Dohme; S1801 ClinicalTrials.gov number, NCT03698019.).

Advances in the clinical management of uveal melanoma

Melanomas arising in the uveal tract of the eye are a rare form of the disease with a biology and clinical phenotype distinct from their more common cutaneous counterparts. Treatment of primary uveal melanoma with radiotherapy, enucleation or other modalities achieves local control in more than 90% of patients, although 40% or more ultimately develop distant metastases, most commonly in the liver. Until January 2022, no systemic therapy had received regulatory approval for patients with metastatic uveal melanoma, and these patients have historically had a dismal prognosis owing to the limited efficacy of the available treatments. A series of seminal studies over the past two decades have identified highly prevalent early, tumour-initiating oncogenic genomic aberrations, later recurring prognostic alterations and immunological features that characterize uveal melanoma. These advances have driven the development of a number of novel emerging treatments, including tebentafusp, the first systemic therapy to achieve regulatory approval for this disease. In this Review, our multidisciplinary and international group of authors summarize the biology of uveal melanoma, management of primary disease and surveillance strategies to detect recurrent disease, and then focus on the current standard and emerging regional and systemic treatment approaches for metastatic uveal melanoma.

Effectiveness of Adjuvant Pembrolizumab vs High-Dose Interferon or Ipilimumab for Quality-of-Life Outcomes in Patients With Resected Melanoma: A Secondary Analysis of the SWOG S1404 Randomized Clinical Trial

Importance

A key issue for the adjuvant treatment of patients with melanoma is the assessment of the effect of treatment on relapse, survival, and quality of life (QOL).

Objective

To compare QOL in patients with resected melanoma at high risk for relapse who were treated with adjuvant pembrolizumab vs standard of care with either ipilimumab or high-dose interferon α 2b (HDI).

Design, Setting, and Participants

The S1404 phase 3 randomized clinical trial was conducted by the SWOG Cancer Research Network at 211 community/academic sites in the US, Canada, and Ireland. Patients were enrolled from December 2015 to October 2017. Data analysis for this QOL substudy was completed in March 2022. Overall, 832 patients were evaluable for the primary QOL end point.

Interventions

Patients were randomized (1:1) to treatment with adjuvant pembrolizumab vs standard of care with ipilimumab/HDI.

Main Outcomes and Measures

Quality of life was assessed for patients at baseline and cycles 1, 3, 5, 7, and 9 after randomization using the Functional Assessment of Cancer Therapy (FACT) Biological Response Modifiers (FACT-BRM), FACT-General, Functional Assessment of Chronic Illness Therapy-Diarrhea, and European QOL 5-Dimension 3-Level scales. The primary end point was the comparison by arm of cycle 3 FACT-BRM trial outcome index (TOI) scores using linear regression. Linear-mixed models were used to evaluate QOL scores over time. Regression analyses included adjustments for the baseline score, disease stage, and programmed cell death ligand 1 status. A clinically meaningful difference of 5 points was targeted.

Results

Among 1303 eligible patients (median [range] age, 56.7 [18.3-86.0] years; 524 women [40.2%]; 779 men [59.8%]; 10 Asian [0.8%], 7 Black [0.5%], 44 Hispanic [3.4%], and 1243 White [95.4%] individuals), 1188 (91.1%) had baseline FACT-BRM TOI scores, and 832 were evaluable at cycle 3 (ipilimumab/HDI = 267 [32.1%]; pembrolizumab = 565 [67.9%]). Evaluable patients were predominantly younger than 65 years (623 [74.9%]) and male (779 [58.9%]). Estimates of FACT-BRM TOI cycle 3 compliance did not differ by arm (ipilimumab/HDI, 96.0% vs pembrolizumab, 98.3%; P = .25). The adjusted cycle 3 FACT-BRM TOI score was 9.6 points (95% CI, 7.9-11.3; P < .001) higher (better QOL) for pembrolizumab compared with ipilimumab/HDI, exceeding the prespecified clinically meaningful difference. In linear-mixed models, differences by arm exceeded 5 points in favor of pembrolizumab through cycle 7. In post hoc analyses, FACT-BRM TOI scores favored the pembrolizumab arm compared with the subset of patients receiving ipilimumab (difference, 6.0 points; 95% CI, 4.1-7.8; P < .001) or HDI (difference, 17.0 points; 95% CI, 14.6-19.4; P < .001).

Conclusions and Relevance

This secondary analysis of a phase 3 randomized clinical trial found that adjuvant pembrolizumab improved QOL vs treatment with adjuvant ipilimumab or HDI in patients with high-risk resected melanoma.

Trial Registration

ClinicalTrials.gov identifier: NCT02506153.

Neoadjuvant relatlimab and nivolumab in resectable melanoma

Relatlimab and nivolumab combination immunotherapy improves progression-free survival over nivolumab monotherapy in patients with unresectable advanced melanoma1. We investigated this regimen in patients with resectable clinical stage III or oligometastatic stage IV melanoma (NCT02519322). Patients received two neoadjuvant doses (nivolumab 480 mg and relatlimab 160 mg intravenously every 4 weeks) followed by surgery, and then ten doses of adjuvant combination therapy. The primary end point was pathologic complete response (pCR) rate2. The combination resulted in 57% pCR rate and 70% overall pathologic response rate among 30 patients treated. The radiographic response rate using Response Evaluation Criteria in Solid Tumors 1.1 was 57%. No grade 3-4 immune-related adverse events were observed in the neoadjuvant setting. The 1- and 2-year recurrence-free survival rate was 100% and 92% for patients with any pathologic response, compared to 88% and 55% for patients who did not have a pathologic response (P = 0.005). Increased immune cell infiltration at baseline, and decrease in M2 macrophages during treatment, were associated with pathologic response. Our results indicate that neoadjuvant relatlimab and nivolumab induces a high pCR rate. Safety during neoadjuvant therapy is favourable compared to other combination immunotherapy regimens. These data, in combination with the results of the RELATIVITY-047 trial1, provide further confirmation of the efficacy and safety of this new immunotherapy regimen.

Neoadjuvant checkpoint inhibitor immunotherapy for resectable mucosal melanoma

Background

Neoadjuvant checkpoint inhibition (CPI) has recently demonstrated impressive outcomes in patients with stage 3 cutaneous melanoma. However, the safety, efficacy, and outcome of neoadjuvant CPI in patients with mucosal melanoma (MM) are not well studied as MM is a rare melanoma subtype. CPI such as combination nivolumab and ipilimumab achieves response rates of 37-43% in unresectable or metastatic MM but there is limited data regarding the efficacy of these agents in the preoperative setting. We hypothesize that neoadjuvant CPI is a safe and feasible approach for patients with resectable MM.

Method

Under an institutionally approved protocol, we identified adult MM patients with resectable disease who received neoadjuvant anti-PD1 +/- anti-CTLA4 between 2015 to 2019 at our institution. Clinical information include age, gender, presence of nodal involvement or satellitosis, functional status, pre-treatment LDH, tumor mutation status, and treatment data was collected. Outcomes include event free survival (EFS), overall survival (OS), objective response rate (ORR), pathologic response rate (PRR), and grade ≥3 toxicities.

Results

We identified 36 patients. Median age was 62; 58% were female. Seventy-eight percent of patients received anti-PD1 + anti-CTLA4. Node positive disease or satellite lesions was present at the time of treatment initiation in 47% of patients. Primary sites of disease were anorectal (53%), urogenital (25%), head and neck (17%), and esophageal (6%). A minority of patients did not undergo surgery due to complete response (n=3, 8%) and disease progression (n=6, 17%), respectively. With a median follow up of 37.9 months, the median EFS was 9.2 months with 3-year EFS rate of 29%. Median OS had not been reached and 3-year OS rate was 55%. ORR was 47% and PRR was 35%. EFS was significantly higher for patients with objective response and for patients with pathologic response. OS was significantly higher for patients with pathologic response. Grade 3 toxicities were reported in 39% of patients.

Conclusion

Neoadjuvant CPI for resectable MM is a feasible approach with signs of efficacy and an acceptable safety profile. As there is currently no standard approach for resectable MM, this study supports further investigations using neoadjuvant therapy for these patients.

Intermittent MEK inhibition for the treatment of metastatic uveal melanoma

Introduction

Uveal melanoma (UM) is associated with poor outcomes in the metastatic setting and harbors activating mutations resulting in upregulation of MAPK signaling in almost all cases. The efficacy of selumetinib, an oral allosteric inhibitor of MEK1/2, was limited when administered at a continual dosing schedule of 75 mg BID. Preclinical studies demonstrate that intermittent MEK inhibition reduces compensatory pathway activation and promotes T cell activation. We hypothesized that intermittent dosing of selumetinib would reduce toxicity, allow for the administration of increased doses, and achieve more complete pathway inhibition, thus resulting in improved antitumor activity.

Methods

We conducted a phase Ib trial of selumetinib using an intermittent dosing schedule in patients with metastatic UM. The primary objective was to estimate the maximum tolerated dose (MTD) and assess safety and tolerability. Secondary objectives included assessment of the overall response rate (RR), progression-free survival (PFS) and overall survival (OS). Tumor biopsies were collected at baseline, on day 3 (on treatment), and between days 11-14 (off treatment) from 9 patients for pharmacodynamic (PD) assessments.

Results

29 patients were enrolled and received at least one dose of selumetinib across 4 dose levels (DL; DL1: 100 mg BID; DL2: 125 mg BID; DL3: 150 mg BID; DL4: 175 mg BID). All patients experienced a treatment-related adverse event (TRAE), with 5/29 (17%) developing a grade 3 or higher TRAE. Five dose limiting toxicities (DLT) were observed: 2/20 in DL2, 2/5 in DL3, 1/1 in DL4. The estimated MTD was 150 mg BID (DL3), with an estimated probability of toxicity of 29% (90% probability interval 16%-44%). No responses were observed; 11/29 patients achieved a best response of stable disease (SD). The median PFS and OS were 1.8 months (95% CI 1.7, 4.5) and 7.1 months (95% CI 5.3, 11.5). PD analysis demonstrated at least partial pathway inhibition in all samples at day 3, with reactivation between days 11-14 in 7 of those cases.

Conclusions

We identified 150 mg BID as the MTD of intermittent selumetinib, representing a 100% increase over the continuous dose MTD (75 mg BID). However, no significant clinical efficacy was observed using this dosing schedule.

Genomic Correlates of Outcome in Tumor-Infiltrating Lymphocyte Therapy for Metastatic Melanoma

PURPOSE

Adoptive cell therapy (ACT) of tumor-infiltrating lymphocytes (TIL) historically yields a 40%-50% response rate in metastatic melanoma. However, the determinants of outcome are largely unknown.

EXPERIMENTAL DESIGN

We investigated tumor-based genomic correlates of overall survival (OS), progression-free survival (PFS), and response to therapy by interrogating tumor samples initially collected to generate TIL infusion products.

RESULTS

Whole-exome sequencing (WES) data from 64 samples indicated a positive correlation between neoantigen load and OS, but not PFS or response to therapy. RNA sequencing analysis of 34 samples showed that expression of PDE1C, RTKN2, and NGFR was enriched in responders who had improved PFS and OS. In contrast, the expression of ELFN1 was enriched in patients with unfavorable response, poor PFS and OS, whereas enhanced methylation of ELFN1 was observed in patients with favorable outcomes. Expression of ELFN1, NGFR, and PDE1C was mainly found in cancer-associated fibroblasts and endothelial cells in tumor tissues across different cancer types in publicly available single-cell RNA sequencing datasets, suggesting a role for elements of the tumor microenvironment in defining the outcome of TIL therapy.

CONCLUSIONS

Our findings suggest that transcriptional features of melanomas correlate with outcomes after TIL therapy and may provide candidates to guide patient selection.

Case Report: Neuromyelitis Optica After Treatment of Uveal Melanoma With Nivolumab and Ipilimumab

The development of immune checkpoint inhibitors (ICIs) has greatly improved survival of patients with advanced malignancies. ICIs can cause immune-related adverse effects (irAEs) involving any organ. Neurological irAEs are infrequent and have mostly been reported in patients with melanoma. We describe the case of a 57-year-old male with right eye uveal melanoma, gene expression profile (class 2), and PRAME (preferentially expressed antigen in melanoma) positivity, who received plaque brachytherapy with Iodine-125 for 4 days with subsequent adjuvant ICIs (immune checkpoint inhibitors), nivolumab and ipilimumab. 18 weeks after discontinuation of immunotherapy, the patient presented with acute onset of left-sided headaches, pain with eye movements, and vision loss. The patient was tested positive for serum anti-aquaporin-4 antibody (AQP4-Ab) and was diagnosed with neuromyelitis optica spectrum disorder (NMOSD). Subsequently, he was treated with 5 days of intravenous methylprednisolone followed by an oral prednisone taper over 10 weeks, with improvement in symptoms. We report a unique case of neuromyelitis optica spectrum disorder (NMOSD) following treatment with ICIs. To our best knowledge, this is the third reported case in English literature of NMOSD following ICI therapy and the first reported case of NMOSD caused by ICI treatment in uveal melanoma.

Second Primary Malignancies in Patients With Melanoma Subtypes: Analysis of 120,299 Patients From the SEER Database (2000-2016)

Purpose

Evaluate incidence of second primary malignancies (SPM) after non-acral cutaneous melanoma (NACM), acral lentiginous melanoma (ALM), mucosal melanoma (MM), and uveal melanoma (UM).

Patients and Methods

First primary NACM, ALM, MM, and UM cases diagnosed 2000-2016 were extracted from SEER. Seer*Stat was used to calculate excess absolute risks (EAR) and standardized incidence ratios (SIR) of SPMs relative to a matched cohort from the general population. P-value of 0.05 determined significance.

Results

Inclusion criteria was met by 109,385 patients with NACM, 2166 with ALM, 2498 with MM, and 6250 with UM. Increased incidence of malignancies occurred after NACM (SIR 1.51; 95%CI, 1.49-1.54), ALM (SIR 1.59; 95%CI, 1.40-1.81), MM (SIR 2.14; 95%CI, 1.85-2.45), and UM (SIR 1.24; 95%CI, 1.14-1.34) relative to the general population. Cutaneous melanoma occurred more frequently after NACM (SIR 9.54; 95%CI, 9.27-9.83), ALM (SIR 12.19; 95%CI, 9.70-15.14), MM (SIR 10.05; 95%CI, 7.18-13.68), and UM (SIR 2.91; 95%CI, 2.27-3.66). Patients with initial NACM (SIR 2.44; 95%CI, 1.64-3.51) and UM (SIR 44.34; 95%CI, 29.91-63.29) demonstrated increased incidence of eye and orbit melanoma. Renal malignancies occurred more frequently after NACM (SIR 1.24; 95%CI, 1.11-1.38), MM (SIR 3.54; 95%CI, 1.62-6.72) and UM (SIR 1.68; 95%CI, 1.09-2.48). Increased incidence of thyroid malignancies was observed after NACM (SIR 1.83; 95%CI, 1.61-2.06), ALM (SIR 3.74; 95%CI, 1.71-7.11), MM (SIR 4.40; 95%CI, 1.77-9.06), and UM (SIR 3.79; 95%CI, 2.52-5.47). Increased incidence of lymphoma was observed after NACM (SIR 1.20; 95%CI, 1.09-1.31) and ALM (SIR 2.06; 95%CI, 1.13-3.46).

Conclusion

Patients with NACM, ALM, MM, and UM have increased incidence of SPMs compared to that expected from the general population. Each of these melanoma subtypes had increased occurrence of cutaneous melanoma and thyroid cancer; some, but not all, had increased occurrence of renal malignancies, eye and orbit melanoma, and lymphoma.

The vaccine-site microenvironment: impacts of antigen, adjuvant, and same-site vaccination on antigen presentation and immune signaling

Background

A goal of cancer vaccines is to induce strong T cell responses to tumor antigens, but the delivery method, schedule, and formulation of cancer vaccines have not yet been optimized. Adjuvants serve to increase the immune response against vaccine antigens. However, little is known about the impact of adjuvants plus antigen and their delivery schedule on the immunologic milieu in the vaccine-site microenvironment (VSME). We hypothesized that antigen processing and presentation may occur directly in the VSME, that adding the toll-like receptor 3 (TLR3) agonist polyICLC (pICLC) would enhance markers of immune activation, and that the immune signatures would be enhanced further by repeated vaccination in the same skin site rather than after multiple vaccines in different skin locations.

Methods

Using RNA sequencing, we evaluated VSME biopsies from patients undergoing subcutaneous/intradermal peptide vaccination against melanoma, with incomplete Freund’s adjuvant (IFA) with or without pICLC. Differential gene expression analyses and gene set enrichment analyses were performed using R. False discovery rate corrected p values <0.05 were considered significant.

Results

We found that addition of peptide antigens to IFA enhanced antigen presentation pathways and a tertiary lymphoid structure gene-signature locally at the VSME. Addition of pICLC to IFA + peptide induced an immunologically favorable VSME 1 week after injection but had little impact on the VSME after three injections, compared with IFA + peptide alone. Repeated same-site injection of IFA + peptide antigens induced a VSME with more dendritic cell activation, Th1 dominance, and TLR adaptor protein gene expression than that induced by injections at different, rotating skin locations.

Conclusions

These data suggest that the vaccine-site itself may be a critically important location contributing to vaccine immunity rather than just the draining lymph node, that IFA induces a favorable VSME with TLR agonist being most beneficial early in the vaccine course, and that same-site injections lead to persistent stimulation of immune pathways that may be beneficial in eliciting antigen specific T cell expansion.

Adjuvant Pembrolizumab versus IFNα2b or Ipilimumab in Resected High-Risk Melanoma

We conducted a randomized phase III trial to evaluate whether adjuvant pembrolizumab for one year (647 patients) improved recurrence-free survival (RFS) or overall survival (OS) in comparison with high-dose IFNα-2b for one year or ipilimumab for up to three years (654 patients), the approved standard-of-care adjuvant immunotherapies at the time of enrollment for patients with high-risk resected melanoma. At a median follow-up of 47.5 months, pembrolizumab was associated with significantly longer RFS than prior standard-of-care adjuvant immunotherapies [HR, 0.77; 99.62% confidence interval (CI), 0.59-0.99; P = 0.002]. There was no statistically significant association with OS among all patients (HR, 0.82; 96.3% CI, 0.61-1.09; P = 0.15). Proportions of treatment-related adverse events of grades 3 to 5 were 19.5% with pembrolizumab, 71.2% with IFNα-2b, and 49.2% with ipilimumab. Therefore, adjuvant pembrolizumab significantly improved RFS but not OS compared with the prior standard-of-care immunotherapies for patients with high-risk resected melanoma.

SIGNIFICANCE

Adjuvant PD-1 blockade therapy decreases the rates of recurrence, but not survival, in patients with surgically resectable melanoma, substituting the prior standard-of-care immunotherapies for this cancer. See related commentary by Smithy and Shoushtari, p. 599. This article is highlighted in the In This Issue feature, p. 587.

Cutaneous adverse events in 155 patients with metastatic melanoma consecutively treated with anti-CTLA4 and anti-PD1 combination immunotherapy: Incidence, management, and clinical benefit

BACKGROUND

In response to the increased use of combination checkpoint inhibitors (CPIs) and the resulting increased cutaneous adverse events (CAEs), this study reviewed patients with melanoma treated with combination CPIs to characterize CAE features and their clinical impact, correlation to adverse events in other organs, and correlation to tumor response.

METHODS

Patients from the authors' institutional database who received at least 1 dose of ipilimumab in combination with either nivolumab or pembrolizumab between January 1, 2012, and December 31, 2017, for stage IV or unresectable stage III melanoma were identified. The time to next treatment (TTNT) was calculated from the start of CPI therapy to the start of the next treatment or death, and the development of CAEs was tested in a time-dependent Cox regression to identify associations with TTNT.

RESULTS

Eighty-one patients (52.3%) experienced a total of 92 CAEs, including eczematous dermatitis (25.0%), morbilliform eruption (22.8%), vitiligo (12.0%), and pruritus without rash (8.7%). The median times to the onset and resolution of CAEs were 21 days (range, 0-341 days) and 50 days (range, 1-352 days), respectively. Most CAEs resolved after patients entered the CPI maintenance phase and treatment with oral antihistamines with or without topical steroids. CPI discontinuation occurred in 4 patients (2.6%) because of CAEs, in 49 (31.6%) because of other immune-related adverse events, and in 20 (12.9%) because of melanoma progression or death. For patients definitively treated with CPIs (n = 134; 86.5%), TTNT was significantly longer with CAEs than without CAEs (hazard ratio, 0.567; 95% CI, 0.331-0.972; P = .039).

CONCLUSIONS

CAEs were mostly reversible and rarely required therapy discontinuation. The development of CAEs was associated with a longer TTNT, and this suggested a possible clinical benefit.

Dietary fiber and probiotics influence the gut microbiome and melanoma immunotherapy response

Gut bacteria modulate the response to immune checkpoint blockade (ICB) treatment in cancer, but the effect of diet and supplements on this interaction is not well studied. We assessed fecal microbiota profiles, dietary habits, and commercially available probiotic supplement use in melanoma patients and performed parallel preclinical studies. Higher dietary fiber was associated with significantly improved progression-free survival in 128 patients on ICB, with the most pronounced benefit observed in patients with sufficient dietary fiber intake and no probiotic use. Findings were recapitulated in preclinical models, which demonstrated impaired treatment response to anti–programmed cell death 1 (anti–PD-1)–based therapy in mice receiving a low-fiber diet or probiotics, with a lower frequency of interferon-γ–positive cytotoxic T cells in the tumor microenvironment. Together, these data have clinical implications for patients receiving ICB for cancer.

Phase I/II trial of a long peptide vaccine (LPV7) plus toll-like receptor (TLR) agonists with or without incomplete Freund's adjuvant (IFA) for resected high-risk melanoma

BACKGROUND

We performed a clinical trial to evaluate safety and immunogenicity of a novel long peptide vaccine administered in combinations of incomplete Freund's adjuvant (IFA) and agonists for TLR3 (polyICLC) and TLR7/8 (resiquimod). We hypothesized that T cell responses to minimal epitope peptides (MEPs) within the long peptides would be enhanced compared with prior vaccines with MEP themselves and that T cell responses would be enhanced with TLR agonists, compared with IFA alone.

METHODS

Participants with resected stage IIB-IV melanoma were vaccinated with seven long melanoma peptides (LPV7) from tyrosinase, gp100, MAGE-A1, MAGE-A10, and NY-ESO-1, each containing a known MEP for CD8+ T cells, plus a tetanus helper peptide (Tet) restricted by Class II MHC. Enrollment was guided by an adaptive design to one of seven adjuvant combinations. Vaccines were administered at weeks 1, 2, 3, 6, 9, 12 at rotating injection sites. T cell and IgG antibody (Ab) responses were measured with IFN-gamma ELIspot assay ex vivo and ELISA, respectively.

RESULTS

Fifty eligible participants were assigned to seven study groups, with highest enrollment on arm E (LPV7+Tet+IFA+polyICLC). There was one dose-limiting toxicity (DLT) in Group E (grade 3 injection site reaction, 6% DLT rate). All other treatment-related adverse events were grades 1-2. The CD8+ T cell immune response rate (IRR) to MEPs was 18%, less than in prior studies using MEP vaccines in IFA. The CD8+ T cell IRR trended higher for IFA-containing adjuvants (24%) than adjuvants containing only TLR agonists (6%). Overall T cell IRR to full-length LPV7 was 30%; CD4+ T cell IRR to Tet was 40%, and serum Ab IRR to LPV7 was 84%. These IRRs also trended higher for IFA-containing adjuvants (36% vs 18%, 48% vs 24%, and 97% vs 60%, respectively).

CONCLUSIONS

The LPV7 vaccine is safe with each of seven adjuvant strategies and induced T cell responses to CD8 MEPs ex vivo in a subset of patients but did not enhance IRRs compared with prior vaccines using short peptides. Immunogenicity was supported more by IFA than by TLR agonists alone and may be enhanced by polyICLC plus IFA.

TRIAL REGISTRATION NUMBER

NCT02126579.

Gut microbiota signatures are associated with toxicity to combined CTLA-4 and PD-1 blockade

Treatment with combined immune checkpoint blockade (CICB) targeting CTLA-4 and PD-1 is associated with clinical benefit across tumor types, but also a high rate of immune-related adverse events. Insights into biomarkers and mechanisms of response and toxicity to CICB are needed. To address this, we profiled the blood, tumor and gut microbiome of 77 patients with advanced melanoma treated with CICB, with a high rate of any ≥grade 3 immune-related adverse events (49%) with parallel studies in pre-clinical models. Tumor-associated immune and genomic biomarkers of response to CICB were similar to those identified for ICB monotherapy, and toxicity from CICB was associated with a more diverse peripheral T-cell repertoire. Profiling of gut microbiota demonstrated a significantly higher abundance of Bacteroides intestinalis in patients with toxicity, with upregulation of mucosal IL-1β in patient samples of colitis and in pre-clinical models. Together, these data offer potential new therapeutic angles for targeting toxicity to CICB.

Immunotherapy combined with high- and low-dose radiation to all sites leads to complete clearance of disease in a patient with metastatic vaginal melanoma

A 73-year-old woman with metastatic vaginal mucosal melanoma that had progressed on ipilimumab and nivolumab experienced clinical and radiographic complete response to dual checkpoint inhibitor immunotherapy given in combination with high-dose plus low-dose radiation. General characteristics and treatment options in this disease are highlighted.

The efficacy of anti-programmed cell death protein 1 therapy among patients with metastatic acral and metastatic mucosal melanoma

Background

Anti‐programmed cell death protein 1 (PD‐1) antibodies are a standard treatment for metastatic melanoma patients. However, the understanding of the efficacy of anti‐PD‐1 for acral melanoma (AM) and mucosal melanoma (MM) is limited as these subtypes are relatively rare compared to cutaneous melanoma (CM).

Methods

This single institution, retrospective cohort study included patients with advanced AM and MM who underwent anti‐PD‐1 therapy for metastatic melanoma between 2012 and 2018. Objective responses were determined using the investigator‐assessed Response Evaluation Criteria in Solid Tumors version 1.1. Progression‐free survival (PFS) and overall survival (OS) were assessed using the Kaplan–Meier method. A Cox regression analysis was performed to identify the factors associated with survival outcomes.

Results

Ninety‐seven patients were identified, 38 (39%) with AM and 59 (61%) with MM. The objective response rates (ORRs) were 21.0% and 15.2% in patients with AM and MM, respectively. The median PFS and OS were 3.6 and 25.7 months for AM patients, and 3.0 and 20.1 months for MM patients, respectively. Elevated serum lactate dehydrogenase (LDH) (AM: hazard ratio [HR], 0.22; 95% confidence interval [CI], 0.06–0.87; p = 0.03, MM: HR, 0.20; 95% CI, 0.08–0.53; p = 0.001) was significantly associated with shorter OS for both subtypes.

Conclusions

The ORR, PFS, and OS with anti‐PD‐1 therapy were poor in patients with AM and MM compared to those previously reported clinical trials for nonacral CM. High serum LDH was associated with significantly shorter OS.

Influence of injection technique, drug formulation and tumor microenvironment on intratumoral immunotherapy delivery and efficacy

BACKGROUND

Intratumoral delivery of immunotherapeutics represents a compelling solution to directly address local barriers to tumor immunity. However, we have previously shown that off-target delivery is a substantial problem during intratumoral injections; this can lead to diminished drug efficacy and systemic toxicities. We have identified three variables that influence intratumoral drug delivery: injection technique, drug formulation and tumor microenvironment. The purpose of this study was to characterize the impact of modifications in each variable on intratumoral drug delivery and immunotherapy efficacy.

METHODS

Intratumoral injections were performed in a hybrid image-guided intervention suite with ultrasound, fluoroscopy and CT scanning capabilities in both rat and mouse syngeneic tumor models. Intratumoral drug distribution was quantified by CT volumetric imaging. The influence of varying needle design and hydrogel-based drug delivery on the immune response to a stimulator of interferon genes (STING) agonist was evaluated using flow cytometry and single cell RNA sequencing. We also evaluated the influence of tumor stiffness on drug injection distribution.

RESULTS

Variations in needle design, specifically with the use of a multiside hole needle, led to approximately threefold improvements in intratumoral drug deposition relative to conventional end-hole needles. Likewise, delivery of a STING agonist through a multiside hole needle led to significantly increased expression of type I interferon-associated genes and 'inflammatory' dendritic cell gene signatures relative to end-hole STING agonist delivery. A multidomain peptide-based hydrogel embedded with a STING agonist led to substantial improvements in intratumoral deposition; however, the hydrogel was noted to generate a strong immune response against itself within the target tumor. Evaluation of tumor stroma on intratumoral drug delivery revealed that there was a greater than twofold improvement in intratumoral distribution in soft tumors (B16 melanoma) compared with firm tumors (MC38 colorectal).

CONCLUSIONS

Injection technique, drug formulation and tumor stiffness play key roles in the accurate delivery of intratumoral immunotherapeutics.

Immune profiling of uveal melanoma identifies a potential signature associated with response to immunotherapy

Background

To date, no systemic therapy, including immunotherapy, exists to improve clinical outcomes in metastatic uveal melanoma (UM) patients. To understand the role of immune infiltrates in the genesis, metastasis, and response to treatment for UM, we systematically characterized immune profiles of UM primary and metastatic tumors, as well as samples from UM patients treated with immunotherapies.

Methods

Relevant immune markers (CD3, CD8, FoxP3, CD68, PD-1, and PD-L1) were analyzed by immunohistochemistry on 27 primary and 31 metastatic tumors from 47 patients with UM. Immune gene expression profiling was conducted by NanoString analysis on pre-treatment and post-treatment tumors from patients (n=6) receiving immune checkpoint blockade or 4-1BB and OX40 dual costimulation. The immune signature of UM tumors responding to immunotherapy was further characterized by Ingenuity Pathways Analysis and validated in The Cancer Genome Atlas data set.

Results

Both primary and metastatic UM tumors showed detectable infiltrating lymphocytes. Compared with primary tumors, treatment-naïve metastatic UM showed significantly higher levels of CD3+, CD8+, FoxP3+ T cells, and CD68+ macrophages. Notably, levels of PD-1+ infiltrates and PD-L1+ tumor cells were low to absent in primary and metastatic UM tumors. No metastatic organ-specific differences were seen in immune infiltrates. Our NanoString analysis revealed significant differences in a set of immune markers between responders and non-responders. A group of genes relevant to the interferon-γ signature was differentially up-expressed in the pre-treatment tumors of responders. Among these genes, suppressor of cytokine signaling 1 was identified as a marker potentially contributing to the response to immunotherapy. A panel of genes that encoded pro-inflammatory cytokines and molecules were expressed significantly higher in pre-treatment tumors of non-responders compared with responders.

Conclusion

Our study provides critical insight into immune profiles of UM primary and metastatic tumors, which suggests a baseline tumor immune signature predictive of response and resistance to immunotherapy in UM.

Nivolumab and Ipilimumab in Metastatic Uveal Melanoma: Results From a Single-Arm Phase II Study

PURPOSE

Metastatic uveal melanoma has poor overall survival (OS) and no approved systemic therapy options. Studies of single-agent immunotherapy regimens have shown minimal benefit. There is the potential for improved responses with the use of combination immunotherapy.

PATIENTS AND METHODS

We conducted a phase II study of nivolumab with ipilimumab in patients with metastatic uveal melanoma. Any number of prior treatments was permitted. Patients received nivolumab 1 mg/kg and ipilimumab 3 mg/kg for four cycles, followed by nivolumab maintenance therapy for up to 2 years. The primary outcome of the study was overall response rate (ORR) as determined by RECIST 1.1 criteria. Progression-free survival (PFS), OS, and adverse events were also assessed.

RESULTS

Thirty-five patients were enrolled, and 33 patients were evaluable for efficacy. The ORR was 18%, including one confirmed complete response and five confirmed partial responses. The median PFS was 5.5 months (95% CI, 3.4 to 9.5 months), and the median OS was 19.1 months (95% CI, 9.6 months to NR). Forty percent of patients experienced a grade 3-4 treatment-related adverse event.

CONCLUSION

The combination regimen of nivolumab plus ipilimumab demonstrates activity in metastatic uveal melanoma, with deep and sustained confirmed responses.

Dose-escalation study of vemurafenib with sorafenib or crizotinib in patients with BRAF-mutated advanced cancers

BACKGROUND

BRAF inhibitors are effective in melanoma and other cancers with BRAF mutations; however, patients ultimately develop therapeutic resistance through the activation of alternative signaling pathways such as RAF/RAS or MET. The authors hypothesized that combining the BRAF inhibitor vemurafenib with either the multikinase inhibitor sorafenib or the MET inhibitor crizotinib could overcome therapeutic resistance.

METHODS

Patients with advanced cancers and BRAF mutations were enrolled in a dose-escalation study (3 + 3 design) to determine the maximum tolerated dose (MTD) and the dose-limiting toxicities (DLTs) of vemurafenib with sorafenib (VS) or vemurafenib with crizotinib (VC).

RESULTS

In total, 38 patients (VS, n = 24; VC, n = 14) were enrolled, and melanoma was the most represented tumor type (VS, 38%; VC, 64%). In the VS arm, vemurafenib 720 mg twice daily and sorafenib 400 mg am/200 mg pm were identified as the MTDs, DLTs included grade 3 rash (n = 2) and grade 3 hypertension, and partial responses were reported in 5 patients (21%), including 2 with ovarian cancer who had received previous treatment with BRAF, MEK, or ERK inhibitors. In the VC arm, vemurafenib 720 mg twice daily and crizotinib 250 mg daily were identified as the MTDs, DLTs included grade 3 rash (n = 2), and partial responses were reported in 4 patients (29%; melanoma, n = 3; lung adenocarcinoma, n = 1) who had received previous treatment with BRAF, MEK, and/or ERK inhibitors. Optional longitudinal collection of plasma to assess dynamic changes in circulating tumor DNA demonstrated the elimination of BRAF-mutant DNA from plasma during therapy (P = .005).

CONCLUSIONS

Vemurafenib combined with sorafenib or crizotinib was well tolerated with encouraging activity, including among patients who previously received treatment with BRAF, MEK, or ERK inhibitors.

The Latest on Uveal Melanoma Research and Clinical Trials: Updates from the Cure Ocular Melanoma (CURE OM) Science Meeting (2019)

Uveal melanoma is a rare cancer in adults, but its treatment is one of the clinical unmet needs in the melanoma field. Metastatic disease develops in approximately 50% of patients and is associated with poor survival due to the lack of effective treatment options. It provides a paradigm for cancers that show evidence of aberrant G protein-coupled receptor signaling, tumor dormancy, and liver-selective metastatic tropism and are associated with the loss of the BAP1 tumor suppressor. At the Melanoma Research Foundation CURE OM Science Meeting at the Society for Melanoma Research Meeting held in Utah on November 20, 2019, clinicians and researchers presented findings from their studies according to three themes within uveal melanoma: (i) ongoing clinical trials, (ii) molecular determinants, and (iii) novel targets that could be translated into clinical trials. This meeting underscored the high interest in the uveal melanoma research field and the unmet need for effective treatment strategies for late-stage disease. Findings from ongoing clinical trials are promising, and multiple studies show how novel combinatorial strategies increase response rates. Novel targets and tumor vulnerabilities identified bioinformatically or through high-throughput screens also reveal new opportunities to target uveal melanoma. The future directions pursued by the uveal melanoma research field will likely have an impact on other cancer types that harbor similar genetic alterations and/or show similar biological properties.

Abstract A09: Characteristics of uveal melanoma patients with central nervous system metastases

In contrast to cutaneous melanoma, central nervous system (CNS) metastasis from uveal melanoma are uncommon, occurring in less than 5% of uveal patients. There is no published literature describing the features or survival of this unique population. Here we describe the clinical characteristics and outcomes of uveal melanoma CNS metastasis patients. We performed an MD Anderson Cancer Center institutional database review from 1999–2017 for consecutive uveal melanoma patients with CNS metastasis. Excluding dural-based metastases, 19 patients were identified. Ethnic makeup was 84% White, 11% Hispanic, 5% other, and median age at diagnosis was 52.4 years. The gender distribution was 12 (63%) female and 7 (37%) male. Primary tumor location in the uveal tract was 26% choroid, 11% iridociliary, 5% chiliochoroidal, and 58% not otherwise specified. Seven of 19 (37%) patients were treated with enucleation; 63% received radiation therapy for primary uveal melanoma. Median interval from diagnosis of uveal melanoma to diagnosis of CNS metastasis was 5 years. Only 7 patients had molecular testing for mutations. Of these, all had G-alpha mutations: 4 (57%) with GNAQ, and 3 (43%) with GNA11 hotspot mutations in Q209. At the time of data cutoff, 14 of 19 (74%) patients were deceased. Additional clinical information regarding treatment for CNS metastasis, histopathologic evaluation, and overall survival will be presented at the meeting.

Citation Format: Sapna P. Patel, Patrick Hwu, Michael Davies, Michael Wong, Hussein Tawbi, Rodabe Amaria, Adi Diab, Dan Gombos, Isabella C. Glitza. Characteristics of uveal melanoma patients with central nervous system metastases [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A09.

Management of early melanoma recurrence despite adjuvant anti-PD-1 antibody therapy☆

BACKGROUND

Anti-programmed cell death protein 1 (PD-1) antibodies (PD1) prolong recurrence-free survival in high-risk resected melanoma; however, approximately 25%-30% of patients recur within 1 year. This study describes the pattern of recurrence, management and outcomes of patients who recur with adjuvant PD1 therapy.

PATIENTS AND METHODS

Consecutive patients from 16 centres who recurred having received adjuvant PD1 therapy for resected stage III/IV melanoma were studied. Recurrence characteristics, management and outcomes were examined; patients with mucosal melanoma were analysed separately.

RESULTS

Melanoma recurrence occurred in 147 (17%) of ∼850 patients treated with adjuvant PD1. In those with cutaneous melanoma (n = 136), median time to recurrence was 4.6 months (range 0.3-35.7); 104 (76%) recurred during (ON) adjuvant PD1 after a median 3.2 months and 32 (24%) following (OFF) treatment cessation after a median 12.5 months, including in 21 (15%) who ceased early for toxicity. Fifty-nine (43%) recurred with locoregional disease only and 77 (57%) with distant disease. Of those who recurred locally, 22/59 (37%) subsequently recurred distantly. Eighty-nine (65%) patients received systemic therapy after recurrence. Of those who recurred ON adjuvant PD1, none (0/6) responded to PD1 alone; 8/33 assessable patients (24%) responded to ipilimumab (alone or in combination with PD1) and 18/23 (78%) responded to BRAF/MEK inhibitors. Of those who recurred OFF adjuvant PD1, two out of five (40%) responded to PD1 monotherapy, two out of five (40%) responded to ipilimumab-based therapy and 9/10 (90%) responded to BRAF/MEK inhibitors.

CONCLUSIONS

Most patients who recur early despite adjuvant PD1 develop distant metastases. In those who recur ON adjuvant PD1, there is minimal activity of further PD1 monotherapy, but ipilimumab (alone or in combination with PD1) and BRAF/MEK inhibitors have clinical utility. Retreatment with PD1 may have activity in select patients who recur OFF PD1.

Cumulative Incidence and Predictors of CNS Metastasis for Patients With American Joint Committee on Cancer 8th Edition Stage III Melanoma

PURPOSE

Improved understanding of the incidence, risk factors, and timing of CNS metastasis is needed to inform surveillance strategies for patients with melanoma.

PATIENTS AND METHODS

Clinical data were extracted from the databases of 2 major melanoma centers in the United States and Australia for 1,918 patients with American Joint Committee on Cancer (AJCC) 8th edition stage III melanoma, diagnosed from 1998-2014, who had (negative) baseline CNS imaging within 4 months of diagnosis. The cumulative incidence of CNS metastasis was calculated in the presence of the competing risk of death, from stage III presentation and at benchmark time points 1, 2, and 5 years postdiagnosis.

RESULTS

At a median follow-up of 70.2 months, distant recurrence occurred in 711 patients (37.1%). The first site of distant metastasis was CNS only for 3.9% of patients, CNS and extracranial (EC) for 1.8%, and EC only for 31.4%. Overall, 16.7% of patients were diagnosed with CNS metastasis during follow-up. The cumulative incidence of CNS metastasis was 3.6% (95% CI, 2.9% to 4.6%) at 1 year, 9.6% (95% CI, 8.3% to 11.0%) at 2 years, and 15.8% (95% CI, 14.1% to 17.6%) at 5 years. The risk of CNS metastasis was significantly influenced by patient sex, age, AJCC stage, primary tumor site, and primary tumor mitotic rate in multivariable and conditional analyses. High primary tumor mitotic rate was significantly associated with increased risk of CNS metastasis at diagnosis and all subsequent time points examined.

CONCLUSION

Similar rates of CNS metastasis were observed in 2 large, geographically distinct cohorts of patients with stage III melanoma. The results highlight the importance of primary tumor mitotic rate. Furthermore, they provide a framework for developing evidence-based surveillance strategies and evaluating the impact of contemporary adjuvant therapies on the risk of CNS metastasis development.

Circulating Tumor Cells and Early Relapse in Node-positive Melanoma

PURPOSE

There is a need for sensitive, reproducible biomarkers for patients with stage III melanoma to guide clinical decision making. Circulating tumor cells (CTCs) can be detected in patients with melanoma; however, there are limited data regarding their significance in stage III disease. The aim of this study was to determine whether CTCs are associated with early relapse in stage III melanoma.

EXPERIMENTAL DESIGN

We prospectively assessed CTCs at first presentation in clinic (baseline) for 243 patients with stage III melanoma. CTCs were measured using the CellSearch System. Relapse-free survival (RFS) was compared between patients with one or more baseline CTC versus those with no CTCs. Log-rank test and Cox regression analysis were applied to establish associations of CTCs with RFS.

RESULTS

At least one baseline CTC was identified in 90 of 243 (37%) patients. Forty-five (19%), 67 (28%), 118 (49%), and 13 (5%) patients were stage IIIA, IIIB, IIIC, or IIID, respectively. CTC detection was not associated with substage, or primary tumor characteristics. Multivariable analysis demonstrated that the detection of ≥1 baseline CTC was significantly associated with decreased 6-month RFS [log-rank, P < 0.0001; HR, 3.62, 95% confidence interval (CI), 1.78-7.36; P < 0.0001] and 54-month RFS (log-rank, P = 0.01; HR, 1.69; 95% CI, 1.13-2.54; P = 0.01).

CONCLUSIONS

≥1 CTC was independently associated with melanoma relapse, suggesting that CTC assessment may be useful to identify patients at risk for relapse who could derive benefit from adjuvant therapy.

Intracranial antitumor activity with encorafenib plus binimetinib in patients with melanoma brain metastases: A case series

Background

Sixty percent of patients with stage IV melanoma may develop brain metastases, which result in significantly increased morbidity and a poor overall prognosis. Phase 3 studies of melanoma usually exclude patients with untreated brain metastases; therefore, clinical data for intracranial responses to treatments are limited.

Methods

A multicenter, retrospective case series investigation of consecutive BRAF‐mutant patients with melanoma brain metastases (MBMs) treated with a combination of BRAF inhibitor encorafenib and MEK inhibitor binimetinib was conducted to evaluate the antitumor response. Assessments included the intracranial, extracranial, and global objective response rates (according to the modified Response Evaluation Criteria in Solid Tumors, version 1.1); the clinical benefit rate; the time to response; the duration of response; and safety.

Results

A total of 24 patients with stage IV BRAF‐mutant MBMs treated with encorafenib plus binimetinib in 3 centers in the United States were included. Patients had received a median of 2.5 prior lines of treatment, and 88% had prior treatment with BRAF/MEK inhibitors. The intracranial objective response rate was 33%, and the clinical benefit rate was 63%. The median time to a response was 6 weeks, and the median duration of response was 22 weeks. Among the 21 patients with MBMs and prior BRAF/MEK inhibitor treatment, the intracranial objective response rate was 24%, and the clinical benefit rate was 57%. Similar outcomes were observed for extracranial and global responses. The safety profile for encorafenib plus binimetinib was similar to that observed in patients with melanoma without brain metastases.

Conclusions

Combination therapy with encorafenib plus binimetinib elicited intracranial activity in patients with BRAF‐mutant MBMs, including patients previously treated with BRAF/MEK inhibitors. Further prospective studies are warranted and ongoing.

All clinical trials to date with encorafenib and binimetinib (US Food and Drug Administration–approved in June 2018 for BRAF‐mutated metastatic melanoma) have excluded untreated melanoma brain metastases. This case series provides the first clinical evidence of intracranial activity of the combination of encorafenib plus binimetinib in patients with BRAF‐mutant melanoma with active brain metastases. Intracranial clinical activity is observed for the first time in patients previously treated with BRAF/MEK inhibitors, a population that has not been previously investigated.

Voluntary exercise may activate components of pro-survival risk pathway in the rat heart and potentially modify cell proliferation in the myocardium

Although physical exercise is known to reduce size of infarction, incidence of ventricular arrhythmias, and to improve heart function, molecular mechanisms of this protection are not fully elucidated. We explored the hypothesis that voluntary running, similar to adaptive interventions, such as ischemic or remote preconditioning, may activate components of pro-survival (RISK) pathway and potentially modify cell proliferation. Sprague-Dawley adult male rats freely exercised for 23 days in cages equipped with running wheels, while sedentary controls were housed in standard cages. After 23 days, left ventricular (LV) myocardial tissue samples were collected for the detection of expression and activation of RISK proteins (WB). The day before, a marker of cell proliferation 5-bromo-2'-deoxyuridine (BrdU) was given to all animals to detect its incorporation into DNA of the LV cells (ELISA). Running increased phosphorylation (activation) of Akt, as well as the levels of PKC? and phospho-ERK1/2, whereas BrdU incorporation into DNA was unchanged. In contrast, exercise promoted pro-apoptotic signaling - enhanced Bax/Bcl-2 ratio and activation of GSK-3ß kinase. Results suggest that in the rat myocardium adapted to physical load, natural cardioprotective processes associated with physiological hypertrophy are stimulated, while cell proliferation is not modified. Up-regulation of pro-apoptotic markers indicates potential induction of cell death mechanisms that might lead to maladaptation in the long-term.

Therapy with high-dose Interleukin-2 (HD IL-2) in metastatic melanoma and renal cell carcinoma following PD1 or PDL1 inhibition

Background

Metastatic melanoma (mM) and renal cell carcinoma (mRCC) are often treated with anti-PD-1 based therapy, however not all patients respond and further therapies are needed. High dose interleukin-2 (HD IL-2) can lead to durable responses in a subset of mM and mRCC patients. The efficacy and toxicity of HD IL-2 therapy following anti-PD-1 or anti-PD-L1 therapy have not yet been explored.

Methods

Reports on mM and mRCC patients who had received HD IL-2 after PD-1 or PD-L1 inhibition were queried from the PROCLAIM^SM database. Patient characteristics, toxicity and efficacy were analyzed.

Results

A total of 57 patients (40 mM, 17 mRCC) were treated with high dose IL-2 after PD-1 or PD-L1 inhibition and had data recorded in the PROCLAIM database. The best overall response rate to HD IL-2 was 22.5% for mM (4 complete response (CR), 5 partial responses (PRs)) and 24% for mRCC (2 CRs, 2 PRs). The toxicity related to HD IL-2 observed in these patients was similar to that observed in patients treated with HD IL-2 without prior checkpoint blockade. One patient who had received prior PD-L1 blockade developed drug induced pneumonitis with HD IL-2 requiring steroid therapy.

Conclusion

In this retrospective analysis, HD IL-2 therapy displayed durable antitumor activity in mM and mRCC patients who progressed following treatment with PD-1 and PD-L1 inhibition. The toxicities were generally manageable and consistent with expectations from HD IL-2 but physicians should watch for immune related toxicities such as pneumonitis. This analysis supports the development of randomized prospective trials to assess the proper sequencing and combination of immune checkpoint blockade and cytokine therapy.

Electronic supplementary material

The online version of this article (10.1186/s40425-019-0522-3) contains supplementary material, which is available to authorized users.

Phase 1 study of the combination of vemurafenib, carboplatin, and paclitaxel in patients with BRAF-mutated melanoma and other advanced malignancies

BACKGROUND

BRAF inhibitors are effective against selected BRAFV600 -mutated tumors. Preclinical data suggest that BRAF inhibition in conjunction with chemotherapy has increased therapeutic activity.

METHODS

Patients with advanced cancers and BRAF mutations were enrolled into a dose-escalation study (3+3 design) to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs).

RESULTS

Nineteen patients with advanced cancers and BRAF mutations were enrolled and received vemurafenib (480-720 mg orally twice a day), carboplatin (area under the curve [AUC] 5-6 intravenously every 3 weeks), and paclitaxel (100-135 mg/m2 intravenously every 3 weeks). The MTD was not reached, and vemurafenib at 720 mg twice a day, carboplatin at AUC 5, and paclitaxel at 135 mg/m2 were the last safe dose levels. DLTs included a persistent grade 2 creatinine elevation (n = 1), grade 3 transaminitis (n = 1), and grade 4 thrombocytopenia (n = 1). Non-dose-limiting toxicities that were grade 3 or higher and occurred in more than 2 patients included grade 3/4 neutropenia (n = 5), grade 3/4 thrombocytopenia (n = 5), grade 3 fatigue (n = 4), and grade 3 anemia (n = 3). Of the 19 patients, 5 (26%; all with melanoma) had a partial response (PR; n = 4) or complete response (CR; n = 1); these responses were mostly durable and lasted 3.1 to 54.1 months. Of the 13 patients previously treated with BRAF and/or mitogen-activated protein kinase kinase (MEK) inhibitors, 4 (31%) had a CR (n = 1) or PR (n = 3). Patients not treated with prior platinum therapy had a higher response rate than those who did (45% vs 0%; P = .045).

CONCLUSIONS

The combination of vemurafenib, carboplatin, and paclitaxel is well tolerated and demonstrates encouraging activity, predominantly in patients with advanced melanoma and BRAFV600 mutations, regardless of prior treatment with BRAF and/or MEK inhibitors.

Case Report of Myeloid Sarcoma Masquerading as In-Transit Metastasis at a Previous Melanoma Site: Avoiding a Diagnostic Pitfall

Myeloid sarcoma is a rare extramedullary hematologic malignancy. Accurate and timely diagnosis may be challenging because myeloid sarcoma is known to mimic solid tumors, including hepatobiliary, nasopharyngeal, and breast carcinomas. We report a case of myeloid sarcoma that developed in the primary tumor lymphatic drainage field of a previously treated intermediate-thickness cutaneous melanoma, clinically and radiographically mimicking an in-transit metastasis, in a patient with myelodysplastic syndrome. The diagnosis of myeloid sarcoma was achieved after surgical excision of the mass and pathological examination that included extensive immunohistochemical studies. Awareness of such an unusual clinical presentation can help reduce diagnostic delay and ensure that adequate tissue is obtained for pathological examination and ancillary studies that are critical for accurate diagnosis and appropriate patient management.

Neoadjuvant immune checkpoint blockade in high-risk resectable melanoma

Preclinical studies suggest that treatment with neoadjuvant immune checkpoint blockade is associated with enhanced survival and antigen-specific T cell responses compared with adjuvant treatment¹; however, optimal regimens have not been defined. Here we report results from a randomized phase 2 study of neoadjuvant nivolumab versus combined ipilimumab with nivolumab in 23 patients with high-risk resectable melanoma ( NCT02519322 ). RECIST overall response rates (ORR), pathologic complete response rates (pCR), treatment-related adverse events (trAEs) and immune correlates of response were assessed. Treatment with combined ipilimumab and nivolumab yielded high response rates (RECIST ORR 73%, pCR 45%) but substantial toxicity (73% grade 3 trAEs), whereas treatment with nivolumab monotherapy yielded modest responses (ORR 25%, pCR 25%) and low toxicity (8% grade 3 trAEs). Immune correlates of response were identified, demonstrating higher lymphoid infiltrates in responders to both therapies and a more clonal and diverse T cell infiltrate in responders to nivolumab monotherapy. These results describe the feasibility of neoadjuvant immune checkpoint blockade in melanoma and emphasize the need for additional studies to optimize treatment regimens and to validate putative biomarkers.

Abstract 3640: Treatment strategies using anti-PD1/PD-L1 (anti-PD) and BRAF/MEK inhibitor (BRAFi) therapy: a retrospective study comparing sequential vs. concurrent administration in BRAF-mutated metastatic melanoma (BMMM)

Background: It is unclear whether anti-PD and BRAFi therapy should be administered sequentially or concurrently in patients (pts) with BMMM, although clinical trials using varying strategies are ongoing. We performed a retrospective, single-center analysis of BMMM pts who received anti-PD therapy either sequentially or concurrent with BRAFi therapy. Methods: A total of 457 metastatic melanoma pts (excluding uveal) were treated with anti-PD therapy at MD Anderson Cancer Center from 11/2009-12/2015. Of those, 148 pts had BMMM and were categorized into 4 treatment groups: BRAFi-naïve treated with anti-PD alone (group 1) N=39 (26%); BRAFi-naive treated with combination therapy (group 2) N=30 (20%); BRAFi-refractory treated with anti-PD alone (group 3) N=45 (31%); and BRAFi-refractory treated with combination therapy (group 4) N=34 (23%). Clinical outcomes were analyzed and tabulated for each group. Pretreatment tissue samples were obtained for correlative biomarker immunohistochemistry (IHC) analyses. Results: BMMM pts with elevated LDH are more likely to receive upfront combination therapy. BRAFi-refractory pts have a higher incidence of brain metastases than BRAFi-naïve pts. The clinical outcomes of overall responses, median PFS and OS are provided in the table. Preliminary biomarker IHC analyses in 11 pts showed PD-L1 expression on the tumor cells correlated with median PFS and OS : 15 mo and 22 mo, respectively in 7 pts with PD-L1 &gt;1%, vs. 6.5 mo and 12 mo in 4 pts with PD-L1 &lt;1%. Conclusions: Single-agent anti-PD therapy is an effective strategy in BMMM pts who are either BRAFi-naïve or refractory. Combination therapy of anti-PD and BRAFi in either BRAFi-naïve or refractory BMMM did not appear to improve clinical outcomes. Confirmation data are needed from ongoing prospective randomized clinical trials.

GroupLDH &gt; upper limit normal (%)Prior CNS metastases (%)Prior anti CLTA-4 exposure (%)Number of anti PD-1 doses (#)Overall Responses CRs + PRs (%)Median PFS (mo)Median OS (mo)Group 1 BRAFi-naïve; anti-PD alone23.72317.912.530.8 + 25.6= 56.41021Group 2 BRAFi-naïve; combination37.9206.710.523.3 + 43.3 = 66.6 812.5Group 3 BRAFi- refractory; anti-PD alone254073.31637.8 + 17.8= 55.6925Group 4 BRAFi- refractory; combination17.644.172.711.529.4 + 5.9 = 35.3519

Citation Format: Rodabe N. Amaria, Van A. Trinh, Jun Gu, Susan McIntyre, Carlos Torres Cabala, Rinata Simien, Adi Diab, Hussein A. Tawbi, Michael A. Davies, Michael K. Wong, Patrick Hwu, Isabella C. Glitza, Sapna P. Patel, Wen Jen Hwu. Treatment strategies using anti-PD1/PD-L1 (anti-PD) and BRAF/MEK inhibitor (BRAFi) therapy: a retrospective study comparing sequential vs. concurrent administration in BRAF-mutated metastatic melanoma (BMMM) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3640.