Targeted DNA Sequencing of Cutaneous Melanoma Identifies Prognostic and Predictive Alterations

BACKGROUND

Cutaneous melanoma (CM) can be molecularly classified into four groups: BRAF mutant, NRAS mutant, NF1 mutant and triple wild-type (TWT) tumors lacking any of these three alterations. In the era of immune checkpoint inhibition (ICI) and targeted molecular therapy, the clinical significance of these groups remains unclear. Here, we integrate targeted DNA sequencing with comprehensive clinical follow-up in CM patients.

METHODS

This was a retrospective cohort study that assessed clinical and molecular features from patients with localized or metastatic CM who underwent targeted next-generation sequencing as part of routine clinical care. A total of 254 patients with CM who had a CLIA-certified targeted sequencing assay performed on their tumor tissue were included.

RESULTS

Of the 254 patients with cutaneous melanoma, 77 were BRAF mutant (30.3%), 77 were NRAS mutant (30.3%), 47 were NF1 mutant (18.5%), 33 were TWT (13.0%) and the remaining 20 (7.9%) carried mutations in multiple driver genes (BRAF/NRAS/NF1 co-mutated). The majority of this co-mutation group carried mutations in NF1 (n = 19 or 90%) with co-occurring mutations in BRAF or NRAS, often with a weaker oncogenic variant. Consistently, NF1 mutant tumors harbored numerous significantly co-altered genes compared to BRAF or NRAS mutant tumors. The majority of TWT tumors (n = 29, 87.9%) harbor a pathogenic mutation within a known Ras/MAPK signaling pathway component. Of the 154 cases with available TMB data, the median TMB was 20 (range 0.7-266 mutations/Mb). A total of 14 cases (9.1%) were classified as having a low TMB (≤5 mutations/Mb), 64 of 154 (41.6%) had an intermediate TMB (>5 and ≤20 mutations/Mb), 40 of 154 (26.0%) had a high TMB (>20 and ≤50 mutations/Mb) and 36 of 154 (23.4%) were classified as having a very high TMB (>50 mutations/Mb). NRAS mutant melanoma demonstrated significantly decreased overall survival on multivariable analysis (HR for death 2.95, 95% CI 1.13-7.69, p = 0.027, log-rank test) compared with other TCGA molecular subgroups. Of the 116 patients in our cohort with available treatment data, 36 received a combination of dual ICI with anti-CTLA4 and anti-PD1 inhibition as first-line therapy. Elevated TMB was associated with significantly longer progression-free survival following dual-agent ICI (HR 0.26, 95% CI 0.07-0.90, p = 0.033, log-rank test).

CONCLUSIONS

NRAS mutation in CMs correlated with significantly worse overall survival. Elevated TMB was associated with increased progression-free survival for patients treated with a combination of dual ICI, supporting the potential utility of TMB as a predictive biomarker for ICI response in melanoma.

The therapeutically actionable long non-coding RNA 'T-RECS' is essential to cancer cells' survival in NRAS/MAPK-driven melanoma

Finding effective therapeutic targets to treat NRAS-mutated melanoma remains a challenge. Long non-coding RNAs (lncRNAs) recently emerged as essential regulators of tumorigenesis. Using a discovery approach combining experimental models and unbiased computational analysis complemented by validation in patient biospecimens, we identified a nuclear-enriched lncRNA (AC004540.4) that is upregulated in NRAS/MAPK-dependent melanoma, and that we named T-RECS. Considering potential innovative treatment strategies, we designed antisense oligonucleotides (ASOs) to target T-RECS. T-RECS ASOs reduced the growth of melanoma cells and induced apoptotic cell death, while having minimal impact on normal primary melanocytes. Mechanistically, treatment with T-RECS ASOs downregulated the activity of pro-survival kinases and reduced the protein stability of hnRNPA2/B1, a pro-oncogenic regulator of MAPK signaling. Using patient- and cell line- derived tumor xenograft mouse models, we demonstrated that systemic treatment with T-RECS ASOs significantly suppressed the growth of melanoma tumors, with no noticeable toxicity. ASO-mediated T-RECS inhibition represents a promising RNA-targeting approach to improve the outcome of MAPK pathway-activated melanoma.

The therapeutically actionable long non-coding RNA 'T-RECS' is essential to cancer cells' survival in NRAS/MAPK-driven melanoma

Finding effective therapeutic targets to treat NRAS-mutated melanoma remains a challenge. Long non-coding RNAs (lncRNAs) recently emerged as essential regulators of tumorigenesis. Using a discovery approach combining experimental models and unbiased computational analysis complemented by validation in patient biospecimens, we identified a nuclear-enriched lncRNA (AC004540.4) that is upregulated in NRAS/MAPK-dependent melanoma, and that we named T-RECS. Considering potential innovative treatment strategies, we designed antisense oligonucleotides (ASOs) to target T-RECS. T-RECS ASOs reduced the growth of melanoma cells and induced apoptotic cell death, while having minimal impacton normal primary melanocytes. Mechanistically, treatment with T-RECS ASOs downregulated the activity of pro-survival kinases and reduced the protein stability of hnRNPA2/B1, a pro-oncogenic regulator of MAPK signaling. Using patient- and cell line- derived tumor xenograft mouse models, we demonstrated that systemic treatment with T-RECS ASOs significantly suppressed the growth of melanoma tumors, with no noticeable toxicity. ASO-mediated T-RECS inhibition represents a promising RNA-targeting approach to improve the outcome of MAPK pathway-activated melanoma.

Pulsed Electric Fields in Oncology: A Snapshot of Current Clinical Practices and Research Directions from the 4th World Congress of Electroporation

The 4th World Congress of Electroporation (Copenhagen, 9-13 October 2022) provided a unique opportunity to convene leading experts in pulsed electric fields (PEF). PEF-based therapies harness electric fields to produce therapeutically useful effects on cancers and represent a valuable option for a variety of patients. As such, irreversible electroporation (IRE), gene electrotransfer (GET), electrochemotherapy (ECT), calcium electroporation (Ca-EP), and tumour-treating fields (TTF) are on the rise. Still, their full therapeutic potential remains underappreciated, and the field faces fragmentation, as shown by parallel maturation and differences in the stages of development and regulatory approval worldwide. This narrative review provides a glimpse of PEF-based techniques, including key mechanisms, clinical indications, and advances in therapy; finally, it offers insights into current research directions. By highlighting a common ground, the authors aim to break silos, strengthen cross-functional collaboration, and pave the way to novel possibilities for intervention. Intriguingly, beyond their peculiar mechanism of action, PEF-based therapies share technical interconnections and multifaceted biological effects (e.g., vascular, immunological) worth exploiting in combinatorial strategies.

Resistance to Immune Checkpoint Blockade: IFNγ or MHC-I?

Resistance to immune checkpoint blockade (ICB), a subject of increasing interest and relevance in the current cancer treatment landscape, is likely induced by several different and incompletely understood mechanisms, including host T-cell dysfunction/exhaustion, T-cell exclusion from the tumor microenvironment, and tumor-specific changes that dampen the antitumor immune response. In this issue, Kawase and colleagues examine tumor-specific changes that might contribute to anti-PD-1 resistance with a particular focus on reduced MHC class I expression as a potential mechanism of innate and acquired resistance to ICB. See related article by Kawase et al. (1).

Initial Evidence for the Efficacy of Naporafenib in Combination With Trametinib in NRAS-Mutant Melanoma: Results From the Expansion Arm of a Phase Ib, Open-Label Study

PURPOSE

No approved targeted therapy for the treatment of patients with neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS)-mutant melanoma is currently available.

PATIENTS AND METHODS

In this phase Ib escalation/expansion study (ClinicalTrials.gov identifier: NCT02974725), the safety, tolerability, and preliminary antitumor activity of naporafenib (LXH254), a BRAF/CRAF protein kinases inhibitor, were explored in combination with trametinib in patients with advanced/metastatic KRAS- or BRAF-mutant non-small-cell lung cancer (escalation arm) or NRAS-mutant melanoma (escalation and expansion arms).

RESULTS

Thirty-six and 30 patients were enrolled in escalation and expansion, respectively. During escalation, six patients reported grade ≥3 dose-limiting toxicities, including dermatitis acneiform (n = 2), maculopapular rash (n = 2), increased lipase (n = 1), and Stevens-Johnson syndrome (n = 1). The recommended doses for expansion were naporafenib 200 mg twice a day plus trametinib 1 mg once daily and naporafenib 400 mg twice a day plus trametinib 0.5 mg once daily. During expansion, all 30 patients experienced a treatment-related adverse event, the most common being rash (80%, n = 24), blood creatine phosphokinase increased, diarrhea, and nausea (30%, n = 9 each). In expansion, the objective response rate, median duration of response, and median progression-free survival were 46.7% (95% CI, 21.3 to 73.4; 7 of 15 patients), 3.75 (95% CI, 1.97 to not estimable [NE]) months, and 5.52 months, respectively, in patients treated with naporafenib 200 mg twice a day plus trametinib 1 mg once daily, and 13.3% (95% CI, 1.7 to 40.5; 2 of 15 patients), 3.75 (95% CI, 2.04 to NE) months, and 4.21 months, respectively, in patients treated with naporafenib 400 mg twice a day plus trametinib 0.5 mg once daily.

CONCLUSION

Naporafenib plus trametinib showed promising preliminary antitumor activity in patients with NRAS-mutant melanoma. Prophylactic strategies aimed to lower the incidence of skin-related events are under investigation.

Retrospective study of the incidence of sarcoidosis-like reaction in patients treated with immunotherapy

AIM

To assess the frequency of radiographically evident drug-induced sarcoidosis-like reaction (DISR) in patients treated with anti-cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) therapy, anti-programmed cell death protein 1 (PD-1) therapy, or a combination of both in a single centre.

MATERIALS AND METHODS

The images and medical records of 457 patients with metastatic melanoma or head and neck cancer treated with either anti-CTLA-4 therapy, anti-PD-1 therapy, or a combination of both at University of California medical centre were reviewed retrospectively and the incidence of radiological manifestations of DISR was assessed among these treatment groups.

RESULTS

Radiological manifestations of DISR were found in 19/457 patients (4.1%). The mean interval from the initiation of immunotherapy to development of DISR was 5.5 months (range 2.3-13.5 months). Mean interval from radiological detection of DISR to imaging evidence of resolution was 5.8 months (range 1.6-18.3 months). Three patients out of 81 (3.7%), 11/297 (3.7%), and 5/79 (6.3%) developed sarcoidosis-like reaction after treatment with anti-CTLA-4 antibody, anti-PD-1 antibody, and a combination of both, respectively. Most patients with DISR were asymptomatic and did not require systemic therapy. Most patients did not demonstrate concomitant increased maximum standardised uptake value (SUVmax) in other organs on their integrated 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)/computed tomography (CT).

CONCLUSIONS

In the present retrospective study of patients treated with immune checkpoint inhibitors (ICIs), DISR occurred in approximately 3.7% of patients treated with either anti-CTLA-4 or anti-PD-1 antibody and 6.3% of patients treated with a combination of both.

Melanoma risk during immunomodulating treatment

Immunosuppressive therapy is standard for the treatment of inflammatory diseases and for minimizing rejection in transplant patients. However, immunosuppressant drugs are associated with an increased risk of certain cancers. In particular, melanoma is an immunogenic tumor and as such, is strongly influenced by the immune system. We performed this literature review to summarize the effects of commonly used immunomodulating agents on melanoma development, recurrence and progression. We outline the mechanism of action of each drug and discuss the available evidence on its influence on melanoma. Based on existing literature, we recommend avoiding the following agents in patients with a history of invasive melanoma: cyclosporine, sirolimus, natalizumab, IL-6 inhibitors, cyclophosphamide, methotrexate and the tumor necrosis factor-alpha inhibitors infliximab and etanercept. If there are no viable alternative agents, we recommend for these patients to see a dermatologist every 6 months for a thorough skin examination.

Amplification of the CXCR3/CXCL9 axis via intratumoral electroporation of plasmid CXCL9 synergizes with plasmid IL-12 therapy to elicit robust anti-tumor immunity

Clinical studies have demonstrated that local expression of the cytokine IL-12 drives interferon-gamma expression and recruits T cells to the tumor microenvironment, ultimately yielding durable systemic T cell responses. Interrogation of longitudinal biomarker data from our late-stage melanoma trials identified a significant on-treatment increase of intratumoral CXCR3 transcripts that was restricted to responding patients, underscoring the clinical relevance of tumor-infiltrating CXCR3⁺ immune cells. In this study, we sought to understand if the addition of DNA-encodable CXCL9 could augment the anti-tumor immune responses driven by intratumoral IL-12. We show that localized IL-12 and CXCL9 treatment reshapes the tumor microenvironment to promote dendritic cell licensing and CD8⁺ T cell activation. Additionally, this combination treatment results in a significant abscopal anti-tumor response and provides a concomitant benefit to anti-PD-1 therapies. Collectively, these data demonstrate that a functional tumoral CXCR3/CXCL9 axis is critical for IL-12 anti-tumor efficacy. Furthermore, restoring or amplifying the CXCL9 gradient in the tumors via intratumoral electroporation of plasmid CXCL9 can not only result in efficient trafficking of cytotoxic CD8⁺ T cells into the tumor but can also reshape the microenvironment to promote systemic immune response.

Abstract CT197: Phase Ib study of LXH254 + trametinib (TMT) in patients (pts) with NRAS-mutant melanoma

Background: MAPK pathway dysregulation is a characteristic molecular abnormality of melanoma. NRAS mutations in melanoma lead to constitutive MAPK activation and subsequent MEK and ERK activation. Inhibiting the pathway with a combination of BRAF/CRAF and MEK inhibitors (LXH254 and TMT, respectively) has demonstrated synergistic activity in preclinical models of NRAS-mutant melanoma.

Methods: We report data from an open-label, Phase Ib study (NCT02974725), that tested LXH254 + TMT combination in a dose-escalation (ESC) part in pts with KRAS- or BRAF-mutant NSCLC or NRAS-mutant melanoma and in a dose-expansion (EXP) part in NRAS-mutant melanoma pts. In ESC, five dose levels were explored: LXH254 200 mg twice daily (BID) + TMT (1 mg or 0.5 mg) daily (QD); LXH254 400 mg BID + TMT (1 mg or 0.5 mg) QD; LXH254 400 mg BID + TMT 1 mg (QD, 2 wk on/2 wk off). Primary objectives were to evaluate safety and tolerability, and determine the recommended dose for expansion (RDE). Secondary objectives were to characterize pharmacokinetics and pharmacodynamics of LXH254 + TMT, and evaluate antitumor activity.

Results: As of Dec 9, 2021, 36 and 30 pts were enrolled in ESC and EXP, respectively; median age was 63.5 and 69 y, respectively. Pts in ESC and EXP received a median of 3 (range: 1-6) and 2 (range: 1-7) prior treatments, respectively, including IO (ESC: 88.9% pts; EXP: 96.7% pts). All pts from ESC and 24 pts from EXP discontinued, mainly due to progressive disease (61.1% and 60%, respectively); 6 pts were ongoing in EXP at data cut-off. In ESC, Grade ≥3 (G≥3) DLTs were reported in 6 pts: dermatitis acneiform (n=2), maculopapular rash (n=2), increased lipase (n=1), and Stevens-Johnson syndrome (n=1). The RDEs were LXH254 200 mg BID + TMT 1 mg QD and LXH254 400 mg BID + TMT 0.5 mg QD. Treatment-related adverse events (TRAEs) were reported in 34 pts (94.4%) in ESC and all pts in EXP. G≥3 TRAEs in ESC and EXP were experienced by 19 (52.8%) and 24 (80%) pts, respectively; the most common being rash or dermatitis acneiform (13.9% each) in ESC and rash (33.3%) in EXP. One fatal TRAE (hypovolemic shock) was reported in the LXH254 400 mg BID + TMT 0.5 mg QD group. The ORR in EXP was 46.7% (7 pts; 95% CI: 21.3-73.4) for LXH254 200 mg BID + TMT 1 mg QD and 13.3% (2 pts; 95% CI: 1.7-40.5) for LXH254 400 mg BID + TMT 0.5 mg QD; overall in EXP, 9 pts (30%) achieved PR and 13 pts (43.3%) reported SD. In EXP the median DOR was 3.8 months (95% CI: 2.6-7.4). Exposures of LXH254 (200 mg or 400 mg BID) + TMT (0.5 mg or 1 mg QD) vs LXH254 single agent were comparable, indicating no apparent LXH254-TMT interactions. Limited paired tumor biopsy data (n=8) showed substantial MAPK pathway inhibition (DUSP6).

Conclusions: LXH254 in combination with TMT has shown preliminary antitumor activity in the pretreated, NRAS-mutant melanoma population. A Phase II trial of LXH254 combinations in pts with pretreated BRAF- or NRAS-mutant melanoma is currently ongoing (NCT04417621).

Citation Format: Filippo de Braud, Christophe Dooms, Rebecca S. Heist, Celeste Lebbe, Martin Wermke, David Planchard, Dirk Schadendorf, Piotr Rutkowski, Jürgen Wolf, Paolo A. Ascierto, Ignacio Gil-Bazo, Shumei Kato, Maria Wolodarski, Meredith McKean, Eva Muñoz Couselo, Martin Sebastian, Armando Santoro, Vesselina Cooke, Luca Manganelli, Kitty Wan, Anil Gaur, Tanay S. Samant, Jaeyeon Kim, Giordano Caponigro, Xuân-Mai Couillebault, Michele Moschetta, Adil Daud. Phase Ib study of LXH254 + trametinib (TMT) in patients (pts) with NRAS-mutant melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT197.

383 Durable responses with intratumoral electroporation of plasmid interleukin 12 plus pembrolizumab in patients with advanced melanoma progressing on an anti-PD-1 antibody: updated data from keynote 695

Background

Electroporated plasmid interleukin-12 (pIL-12-EP; tavokinogene telseplasmid; TAVO) induces sustained intratumoral expression of IL-12, a cytokine that is integral for response to anti-PD-1 antibodies. Here, we present updated safety and response duration data from KEYNOTE 695, a Phase 2, multicenter, open-label trial of pIL-12-EP in combination with pembrolizumab in patients with stage III/IV melanoma immediately following confirmed progression on an anti-PD-1 antibody.

Methods

Patients with confirmed disease progression after ≥12 weeks‘ treatment with an anti-PD-1 antibody alone or in combination were eligible. Patients received intratumoral pIL-12-EP on days 1, 5 and 8 every 6 weeks and pembrolizumab 200 mg every 3 weeks. Responses were assessed by the investigator at 12-week intervals using RECIST v1.1; overall survival (OS) and duration of response (DoR) assessments were conducted using the Kaplan-Meier method.

Results

Of the first 56 patients treated, 50% had visceral disease (M1b-d), 80% had received 1–2 and 20% ≥3 prior lines of therapy, 27% had prior ipilimumab and 21% prior BRAF/MEK inhibitors. 61% of patients were primary refractory to anti-PD-1. 54 patients were efficacy evaluable, defined as patients who had at least one post-treatment scan. The investigator-assessed objective response rate (ORR) per RECIST was 27.8% (4 CR, 11 PR); ORR per iRECIST was 29.6%. In patients with M1b-d staging, ORR was 33.3% (n=9/27), and in those receiving prior ipilimumab, ORR was 33.3% (n=5/15). Seven patients had 100% reduction in target lesions, and regression was observed in non-injected lesions. The median DoR had not been reached. With a median follow up of 19.3 months, the median OS (95% CI) was 24.5 (14.4, NR) months (figure 1). The study is now fully enrolled. In 105 patients with safety data, there were no Grade 4/5 treatment-related adverse events (TRAEs) reported. Grade 3 TRAEs occurred in 5.7% and comprised cellulitis in two patients and arthralgia, pneumonitis, enteritis, keratoacanthoma, lichen planus and musculoskeletal chest pain in one patient each. The Grade 1/2 TRAEs in ≥10% patients were fatigue (27.6%), procedural pain (20.0%), diarrhea (17.1%), nausea (10.5%) and pruritus (10.5%). ORR by blinded independent central review has commenced and a global phase 3 trial is planned.

Abstract 383 Figure 1

Overall survival in patients treated with pIL-12-EP in combination with pembrolizumab. Dark grey bars: time on study treatment, light grey bars: end of treatment to death or censoring

Conclusions

Patients with anti-PD-1 therapy refractory advanced melanoma can achieve deep, durable responses in both injected and non-injected lesions with pIL-12-EP plus pembrolizumab. Intratumoral pIL-12-EP in combination with pembrolizumab was generally well tolerated, with minimal Grade 3 and no Grade 4/5 TRAEs.

Trial Registration

NCT03132675

Ethics Approval

The study was approved by a central IRB and/or local institutional IRB/Ethics Committee as required for each participating institution.

Consent

Written informed consent was obtained from the patients participating in the trial; the current abstract does not include information requiring additional consent

950 Final analysis: phase 1b study investigating intratumoral injection of toll-like receptor 9 agonist vidutolimod ± pembrolizumab in patients with PD-1 blockade–refractory melanoma

Background

There are limited therapeutic options for patients with progressive disease (PD) on or after PD-1–blocking antibody therapy. Vidutolimod (CMP-001) is a first-in-class, immunostimulatory virus-like particle containing a CpG-A Toll-like receptor 9 (TLR9) agonist. This phase 1b study evaluated the safety and clinical activity of intratumoral vidutolimod with and without pembrolizumab in patients with refractory melanoma.

Methods

This two-part, open-label, multicenter, phase 1b study (NCT02680184) enrolled adults with histologically confirmed metastatic or unresectable cutaneous melanoma who had stable disease after ≥12 weeks or PD on anti−PD-1 treatment, measurable disease per RECIST v1.1, ECOG PS 0/1, and ≥1 lesion accessible for intratumoral injection. Part 1 evaluated vidutolimod + pembrolizumab and Part 2 evaluated vidutolimod monotherapy. Key objectives included assessment of safety and clinical activity, and exploratory analyses were performed on available tumor biopsies using immunohistochemistry and RNAseq.

Results

At data cutoff (August 17, 2021), 159 patients had enrolled in Part 1 and 40 patients in Part 2. The median age was 64 years in Part 1 (range, 30-90) and 68 years in Part 2 (range, 30-89). Most patients had PD as their last response to prior anti–PD-1 therapy (Part 1, 93.1%; Part 2, 80.0%). Grade 3/4 treatment-related adverse events (TRAEs) occurred in 37.1% of patients treated with vidutolimod + pembrolizumab and in 22.5% of patients treated with vidutolimod monotherapy. No treatment-related deaths occurred. Based on the efficacy data presented in Table 1, vidutolimod polysorbate 20 (PS20) A was selected for further development as this formulation in combination with pembrolizumab had a best objective response rate (ORR; RECIST v1.1) of 23.5%, with a median duration of response (DOR) of 25.2 months. Vidutolimod monotherapy had an ORR of 20.0%, with a median DOR of 5.6 months. Exploratory translational analyses identified association of unique biomarkers with response among patients with T cell–inflamed versus non-T cell–inflamed tumors at baseline.

Abstract 950 Table 1

Safety and clinical activity of vidutolomod ± pembrolizumab

Conclusions

Promising clinical activity was observed with vidutolimod + pembrolizumab and vidutolimod monotherapy in patients with PD-1 blockade–refractory melanoma. A manageable safety profile was observed. The DOR with vidutolimod + pembrolizumab was substantially longer than with vidutolimod monotherapy. Clinical studies to confirm the efficacy of vidutolimod + PD-1 blockade in patients with previously untreated unresectable/metastatic melanoma (phase 2/3, NCT04695977) or PD-1 blockade–refractory melanoma (phase 2, NCT04698187) are ongoing.

Acknowledgements

This work was supported by Checkmate Pharmaceuticals. Medical writing assistance was provided by Steffen Biechele, PhD (ApotheCom, San Francisco, CA, USA), and funded by Checkmate Pharmaceuticals.

Trial Registration

NCT02680184

Ethics Approval

This study was approved by the WCG-WIRB; WIRB approval tracking number: 20152597.

523 Preliminary clinical experience with XmAb20717, a PD-1 x CTLA-4 bispecific antibody, in patients with advanced solid tumors

Background

XmAb20717 is a humanized bispecific monoclonal antibody that simultaneously targets PD-1 and CTLA-4. We report updated data on patients treated at the recommended expansion dose from an ongoing, multicenter, Phase 1, dose-escalation and -expansion study of intravenous XmAb20717 in patients with selected advanced solid tumors that progressed after treatment with all standard therapies or with no standard therapeutic options.

Methods

A maximum tolerated dose was not reached in dose escalation. XmAb20717 10 mg/kg every 2 weeks (Q2W) was selected as the expansion dose, based on consistent T-cell proliferation in peripheral blood indicative of dual PD-1/CTLA-4 checkpoint blockade, and response to treatment (RECIST[1.1]).1 Parallel expansion cohorts included ~20 patients each with melanoma, renal cell carcinoma (RCC), non-small cell lung cancer (NSCLC), castration-resistant prostate cancer (CRPC), and a basket of tumor types without an FDA-approved checkpoint inhibitor (CI). Patients treated with 10 mg/kg in dose escalation were pooled with expansion cohorts for analysis of clinical activity and safety.

Results

As of 9 June 2021, 110 patients, ranging in age from 39 to 89 years and 66.4% male, were treated, and 5 were continuing treatment. Patients had received a median of 4 prior systemic treatment regimens, including CI therapy for 64.5%. The objective response rate was 13.0% (10/77 patients evaluable for efficacy), including 1 complete response (melanoma [confirmed]) and 9 partial responses (confirmed: 1 melanoma, 2 RCC, 2 CRPC, 1 ovarian cancer; unconfirmed: 1 melanoma, 2 NSCLC). The CRPC responders (2/7 with RECIST-measurable disease) had confirmed PSA decreases ≥ 50% from baseline (to 0.02 and 0.3 ng/mL); neither had progression on bone scans. All responders had prior CI exposure, except those with CRPC. Robust CD4 and CD8 T-cell activation was seen. Low baseline tumoral expression of myeloid recruitment genes, including IL-8, was associated with clinical benefit. Grade ≥ 3 immunotherapy-related adverse events in ≥ 3 patients included rash (16.4%), transaminase elevations (9.1%), hyperglycemia (4.5%), acute kidney injury (3.6%), amylase and lipase increased (2.7%), and lipase increased (2.7%).

Conclusions

Preliminary data indicate 10 mg/kg XmAb20717 Q2W was associated with complete and partial responses in multiple tumor types and was generally well-tolerated in these heavily pretreated patients with advanced cancer. Changes in T-cell populations in the periphery and tumor are consistent with robust dual checkpoint blockade. These findings support further development of XmAb20717 in advanced solid tumors, including metastatic prostate cancer.

Trial Registration

NCT03517488

References

Shum E, Daud A, Reilley M, et al. Preliminary safety, pharmacokinetics/pharmacodynamics, and antitumor activity of XmAb20717, a PD-1 x CTLA-4 bispecific antibody, in patients with advanced solid tumors. JITC 2020;8(3):A247-8.

Ethics Approval

The study was approved by each institution’s IRB.

Layilin Anchors Regulatory T Cells in Skin

Regulatory T cells (Tregs) reside in nonlymphoid tissues where they carry out unique functions. The molecular mechanisms responsible for Treg accumulation and maintenance in these tissues are relatively unknown. Using an unbiased discovery approach, we identified LAYN (layilin), a C-type lectin-like receptor, to be preferentially and highly expressed on a subset of activated Tregs in healthy and diseased human skin. Expression of layilin on Tregs was induced by TCR-mediated activation in the presence of IL-2 or TGF-β. Mice with a conditional deletion of layilin in Tregs had reduced accumulation of these cells in tumors. However, these animals somewhat paradoxically had enhanced immune regulation in the tumor microenvironment, resulting in increased tumor growth. Mechanistically, layilin expression on Tregs had a minimal effect on their activation and suppressive capacity in vitro. However, expression of this molecule resulted in a cumulative anchoring effect on Treg dynamic motility in vivo. Taken together, our results suggest a model whereby layilin facilitates Treg adhesion in skin and, in doing so, limits their suppressive capacity. These findings uncover a unique mechanism whereby reduced Treg motility acts to limit immune regulation in nonlymphoid organs and may help guide strategies to exploit this phenomenon for therapeutic benefit.

Long-term outcomes in patients with advanced melanoma who had initial stable disease with pembrolizumab in KEYNOTE-001 and KEYNOTE-006

Objective:

Patients with melanoma and early stable disease (SD) with pembrolizumab have unclear prognosis. We present post hoc analyses of long-term outcomes for patients with early SD, partial response (PR) or complete response (CR) with pembrolizumab.

Patients and methods:

Patients who received pembrolizumab in the KEYNOTE-001 and KEYNOTE-006 studies and had SD, PR or CR at weeks 12 or 24 were included.

Results:

Of 294 patients in the week 12 analysis, 107 (36.4%) had SD at week 12, of whom 7 (6.5%) had a best overall response of CR, 43 (40.2%) had PR and 57 (53.3%) had SD. Forty-eighte–month overall survival (OS) rates were 95.2%, 73.0% and 47.7%, respectively, for patients with CR, PR and SD at week 12. Similar results were observed in the 241 patients in the week 24 analysis. Forty-eight–month OS rates were 72.1% for patients with SD at week 12 followed by subsequent response and 75.0% for patients with PR at week 12 followed by no change in response or progression. Thirty-six–month and 48-month OS rates were 11.6% and not reached, respectively, for patients with SD at week 12 followed by progression before week 24.

Conclusions:

A substantial proportion of patients (46.7%) with early (week 12) SD with pembrolizumab achieved subsequent PR or CR. Patients with SD at week 12 and subsequent CR/PR had similar survival to those who maintained PR. In contrast, patients with SD at week 12 and subsequent progression had poor survival outcomes. These findings may guide treatment decisions for patients achieving early SD.

Trial registration:

Clinicaltrials.gov: NCT01295827 (KEYNOTE-001); NCT01866319 (KEYNOTE-006).

Should Sentinel Lymph Node Biopsy Status Guide Adjuvant Radiation Therapy in Patients With Merkel Cell Carcinoma?

Purpose

Radiation of the draining lymph node basin remains controversial for Merkel cell carcinoma, particularly in the era of sentinel lymph node biopsy (SLNB).

Methods and Materials

Based on a 20-year experience using SLNB-guided adjuvant radiation therapy (RT), we conducted a retrospective review of clinically node-negative patients testing 2 hypotheses: (1) whether nodal RT could be safely omitted in SLNB-negative Merkel cell carcinoma and (2) whether the excised primary site should always be radiated. Clinically node-positive patients were excluded.

Results

Among 57 clinically node-negative patients who underwent SLNB and wide local excision (WLE), 42 (74%) had a negative SLNB, and 15 (26%) had a positive SLNB. At a median follow-up of 43 months (range, 5-182), SLNB-negative patients irradiated to the primary site had improved 4-year disease-specific survival (100% vs 65%, P = .008), local recurrence-free survival (100% vs 76%, P = .009), and distant recurrence-free survival (100% vs 75%, P = .008), but not overall survival (87.5% vs 57.7%, P = .164) compared with SLNB-positive patients receiving comprehensive RT. Among SLNB-negative patients treated with WLE only, 67% (6/9) had a disease relapse, half of which were local relapses (33%).

Conclusions

In this single-institution retrospective review, after negative SLNB and WLE, RT given only to the primary site provided 100% disease control without a need for nodal RT. Among SLNB-negative patients who had WLE, omission of postoperative primary-site RT was associated with 67% cancer relapse, of which half was local.

Abstract CT032: CMP-001 demonstrates improved response in noninflamed anti-PD-1 refractory melanoma and response is associated with serum CXCL10

Background

In the treatment-naive setting, PD-1 blockade is associated with greater response in T cell-inflamed vs non-T cell-inflamed tumors. CMP-001 is a CpG-A oligonucleotide TLR9 agonist in a virus-like particle that is hypothesized to activate tumor-associated plasmacytoid dendritic cells (pDCs) to secrete type I interferons. Through this activity, CMP-001 may convert the tumor microenvironment to a Th1-like chemokine milieu (eg, increased CXCL10) and induce an antitumor CD8+ T-cell response. We have recently reported that intratumoral injection of CMP-001 + IV pembrolizumab (pembro) had an acceptable safety profile and can reverse PD-1 blockade resistance in patients (pts) with melanoma (Milhem et al, SITC 2019). Regression was observed in injected and uninjected lesions. Herein we report pharmacodynamic and translational data.

Methods

This 2-part, open-label, multicenter, phase 1b study (NCT02680184) enrolled pts with metastatic/unresectable melanoma and stable disease (SD) or progressive disease (PD) on/after anti−PD-1 therapy. In part 1 (3+3 dose-escalation and dose-expansion), pts received CMP-001 + pembro. In part 2, pts received CMP-001 monotherapy. Determination of safety and clinical activity were the study's main objectives. Prespecified pharmacodynamic and translational studies evaluated serum chemokines and evaluated tumor biopsies using RNA and/or whole exome sequencing and immunohistochemistry for PD-L1 (reported as H-score), CD8, and CD303 (pDC marker).

Results

As of September 30, 2020, 159 pts (part 1) and 40 pts (part 2) have been treated. A greater median fold increase of serum CXCL10 (a marker of innate immunity, n=40) was observed in responders (R) to CMP-001 + pembro (18.8x) vs nonresponders (NR) after treatment (9.9x in SD; 6.15x in PD; differences were not statistically significant). Preliminary analyses showed that interferon gene expression distinguished R vs NR. Tumor biopsy analyses (part 1, n=139; part 2, n=34) showed that pts with high PD-L1, high CD8+ T cells, or inflamed transcriptional signatures at baseline were less likely to respond to CMP-001 + pembro vs pts without inflammation markers at baseline. Baseline mean PD-L1 expression (H-score) was 8.1 in R (n=10) vs 21.8 in NR (n=49). Posttreatment biopsies generally showed increased PD-L1, CD8+ T cells, and inflamed transcriptional signatures in R vs NR. Neither tumor mutational burden nor baseline pDC density distinguished R vs NR.

Conclusions

In pts with anti-PD-1 refractory melanoma, intratumoral CMP-001 ± pembro appears to disproportionately induce antitumor responses in noninflamed tumors. Clinical response to CMP-001 ± pembro was associated with induction of markers of both innate and adaptive antitumor immunity.

Citation Format: Jason John Luke, Riyue Bao, John M. Kirkwood, Yousef Zakharia, Diwakar Davar, Elizabeth Buchbinder, Theresa Medina, Adil Daud, Antoni Ribas, Jiaxin Niu, Geoffrey Gibney, Kim Margolin, Anthony J. Olszanski, Inderjit Mehmi, Takami Sato, Montaser Shaheen, Aaron Morris, Dmitri Bobilev, Katie Campbell, George Weiner, James E. Wooldridge, Arthur M. Krieg, Mohammed Milhem. CMP-001 demonstrates improved response in noninflamed anti-PD-1 refractory melanoma and response is associated with serum CXCL10 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT032.

Trials in progress: A phase 1, open-label, dose-escalation, pharmacokinetic, safety and tolerability study of the selective TAM kinase inhibitor PF-07265807 in patients with advanced or metastatic solid tumors

TPS2671

Background: MERTK is a receptor tyrosine kinase from the tumor-associated macrophage kinase (TAMK) family that regulates key aspects of immune homeostasis and responses to infection. MERTK inhibition may lower the threshold for immune activation thereby promoting anti-tumor activity. Agents with some degree of MERTK inhibitory activity have been investigated in the clinic, but are limited by poor potency in patients (pts) and significant off-targets effects. PF-07265807 (ARRY-067) is a selective small-molecule inhibitor of the TAMKs MERTK and AXL. In preclinical models, PF-07265807 monotherapy shows antitumor activity that results in long-term cures and resistance to tumor re-challenge when combined with anti-programmed cell death protein 1/programmed death-ligand 1 (anti-PD-1/PD-L1) antibodies. This first-in-human study will evaluate the safety, tolerability, pharmacokinetics (PK) and preliminary anti-tumor activity of PF-07265807 in pts with selected advanced or metastatic solid tumors. This study will also explore the potential utility of PF-07265807 in combination with anti-PD-1/PD-L1 antibodies. Methods: This is a phase 1, open-label, multi-center, dose-escalation study (NCT04458259) to evaluate the safety, PK and tolerability of PF-07265807. Eligible participants will be adult pts with selected advanced or metastatic solid tumors who are intolerant or resistant to standard therapy. Other key eligibility criteria: measurable disease by RECIST 1.1 or non-measurable disease; Eastern Cooperative Oncology Group performance status 0–2; adequate bone marrow, renal and liver function; and resolved acute effects of any prior therapy. Successive cohorts of pts will receive escalating doses of PF-07265807 starting from 25 mg QD. Each cycle will be 21 days in duration (14 days on/7 days off). Study drug treatment will continue until disease progression or unacceptable toxicity, whichever occurs first. For dose escalation, a Bayesian logistic regression model will be used to model the relationship of dose-limiting toxicities (DLTs) to PF-07265807 dose. This model, along with escalation with overdose control, will guide the dose escalation of PF-07265807 after the completion of the DLT observation period (first two cycles of treatment, i.e. 42 days) of each cohort, until determination of the maximum tolerated dose/recommended phase 2 dose (MTD/RP2D). After the MTD/RP2D is identified, the safety and efficacy of combined PF-07265807 and anti-PD1/PD-L1 treatment will be explored. Primary endpoints: incidence of DLTs, treatment-emergent adverse events and laboratory abnormalities. Secondary endpoints: PK parameters of PF-07265807, objective response rate and duration of response. The study began enrolling pts in September 2020 and is still recruiting. Clinical trial information: NCT04458259.

Phase II study of binimetinib with imatinib in patients with unresectable KIT-mutant melanoma

TPS9594

Background: Immune checkpoint inhibitors (ICI) have transformed treatment for patients (pts) with advanced melanoma, as have BRAF/MEK inhibitors for pts with BRAF V600-mutant melanoma. However, pts with acral or mucosal melanomas are in particular need of more options given a lower objective response rate (ORR) to ICI, and lower incidence of BRAF V600 driver mutation. Such BRAF mutations are found in only 5-10% of acral/mucosal melanomas, while KIT mutations/amplifications are found in 10-20%. Even when present, a KIT alteration does not guarantee response to KIT inhibition, with only about one-third responding as previously shown in 3 phase II studies. A significant number of KIT-mutant melanomas have been shown to demonstrate NF1 or SPRED1 loss, with recent preclinical work showing that such alterations are associated with the loss of negative suppression of RAS, resulting in RAS activation and MEK dependence. We hypothesize that NF1 or SPRED1 loss cooperates with KIT mutations to drive melanomagenesis and resistance to KIT inhibition, and propose to target this vulnerability with a combination approach to targeted therapy. This phase II study will be the first to evaluate the efficacy and safety of binimetinib plus imatinib in pts with KIT-mutant melanoma. Methods: This is an investigator-initiated phase II study of binimetinib in combination with imatinib in pts with BRAF V600 WT, KIT-mutant unresectable melanoma who have progressed on or who are ineligible for ICI (NCT04598009). Pts will be ≥18 yo with performance status ECOG 0-2, and have unresectable Stage IIIB/C/D or Stage IV melanoma that is BRAF V600 WT and KIT-mutant by CLIA-certified testing platform. Pts will have progressed on prior ICI or other standard-of-care (SOC) therapies, or be ineligible for or unable to tolerate SOC therapies. Pts with brain metastasis will be eligible if clinically stable and determination made that no CNS-specific treatment is required prior to study start. Pts previously treated with a MEK inhibitor will be excluded. A Simon 2-stage Minimax design will be used; the null hypothesis that the true response rate is 0.1 will be tested against a one-sided alternative. 15 pts will be accrued in the first stage. If there are £1 responses, the study will be stopped. Otherwise, 10 additional pts will be accrued for a total of 25. The null hypothesis that the true response rate is 0.1 will be rejected if ≥6 responses are observed. This yields a type I error rate of 0.05 and power of 0.8017 when the true response rate is 0.3.Primary endpoint: ORR (RECIST). Secondary endpoints: duration of response, progression-free survival, overall survival, clinical benefit rate (CR, PR, or SD ≥16 weeks), safety profile (CTCAE). Exploratory objectives to include investigations of association between clinical response and baseline NF1 and SPRED1 status, and of pathologic correlates of acquired resistance. Study began enrolling pts in December 2020 and is ongoing. Clinical trial information: NCT04598009.

Three-year survival, correlates and salvage therapies in patients receiving first-line pembrolizumab for advanced Merkel cell carcinoma

Background

Merkel cell carcinoma (MCC) is an aggressive skin cancer associated with poor survival. Programmed cell death-1 (PD-1) pathway inhibitors have shown high rates of durable tumor regression compared with chemotherapy for MCC. The current study was undertaken to assess baseline and on-treatment factors associated with MCC regression and 3-year survival, and to explore the effects of salvage therapies in patients experiencing initial non-response or tumor progression after response or stable disease following first-line pembrolizumab therapy on Cancer Immunotherapy Trials Network-09/KEYNOTE-017.

Methods

In this multicenter phase II trial, 50 patients with advanced unresectable MCC received pembrolizumab 2 mg/kg every 3 weeks for ≤2 years. Patients were followed for a median of 31.8 months.

Results

Overall response rate to pembrolizumab was 58% (complete response 30%+partial response 28%; 95% CI 43.2 to 71.8). Among 29 responders, the median response duration was not reached (NR) at 3 years (range 1.0+ to 51.8+ months). Median progression-free survival (PFS) was 16.8 months (95% CI 4.6 to 43.4) and the 3-year PFS was 39.1%. Median OS was NR; the 3-year OS was 59.4% for all patients and 89.5% for responders. Baseline Eastern Cooperative Oncology Group performance status of 0, greater per cent tumor reduction, completion of 2 years of treatment and low neutrophil-to-lymphocyte ratio were associated with response and longer survival. Among patients with initial disease progression or those who developed progression after response or stable disease, some had extended survival with subsequent treatments including chemotherapies and immunotherapies.

Conclusions

This study represents the longest available follow-up from any first-line anti-programmed death-(ligand) 1 (anti-PD-(L)1) therapy in MCC, confirming durable PFS and OS in a proportion of patients. After initial tumor progression or relapse following response, some patients receiving salvage therapies survived. Improving the management of anti-PD-(L)1-refractory MCC remains a challenge and a high priority.

Trial registration number

NCT02267603.

Evaluation of efficiency and quality of the multi-disciplinary team handover process in a mother and baby inpatient setting

Introduction

At Coombe Wood Mother and Baby unit (MBU) there are daily multi-disciplinary team (MDT) handover meetings and a weekly MDT ward round attended by 7-8 team members. There are concerns that the handover is too time consuming, utilising time which could be spent on other clinical duties, and concerns regarding the relevance of information that is handed over.

Objectives

To perform a service evaluation to determine the efficiency and quality of MDT handover meetings in an MBU setting.

Methods

Data was collected from September to October 2020. A checklist was designed listing information felt to be relevant to handover and contained the following data points – ‘current situation’, ‘mental health’, ‘level of observations’, ‘risk’, ‘physical health’, ‘baby care’, ‘baby supervision levels’ and ‘tasks and responsibilities’. The start and stop times of each MDT handover meeting were noted and a record was made as to whether these topics were discussed.

Results

Mean meeting duration was 32.2 minutes (range: 13 – 45 minutes) and amounted to 2.68 hours spent in MDT handover over a 5-day working week. This equates to 21.4 person-hours (based on 8 staff) a week. 928 data points were generated. 50.7% (468) data points were recorded and commonly omitted data points were – ‘tasks and responsibilities’, ‘risk’, ‘level of observations’ and ‘physical health’. On all occasions, ‘current situation’, ‘mental health’ and ‘baby care’ were handed over.

Conclusions

The results of this service evaluation provide compelling evidence for a wider improvement project. Involving MDT staff in designing interventions will make handover meetings more meaningful.

Association of BRAF V600E/K Mutation Status and Prior BRAF/MEK Inhibition With Pembrolizumab Outcomes in Advanced Melanoma: Pooled Analysis of 3 Clinical Trials

Importance

The optimal sequencing of immune checkpoint inhibitors and targeted therapy for BRAF V600E/K-mutant melanoma is not well established.

Objective

To assess the association of BRAF wild-type (WT) or BRAF V600E/K-mutant status and BRAF inhibitor (BRAFi) with or without MEK inhibitor (MEKi) therapy with response to pembrolizumab.

Design, Setting, and Participants

This study is a post hoc subgroup analysis of pooled data from 3 multinational, multisite studies: KEYNOTE-001 (data cutoff September 1, 2017), KEYNOTE-002 (data cutoff May 30, 2018), and KEYNOTE-006 (data cutoff December 4, 2017). Patients included in this analysis were adults with advanced melanoma and known BRAF V600E/K tumor status who had received pembrolizumab.

Interventions

Patients received pembrolizumab in dosages of 2 mg/kg every 3 weeks, 10 mg/kg every 2 weeks, or 10 mg/kg every 3 weeks.

Main Outcomes and Measures

End points were objective response rate (ORR) and progression-free survival (PFS) assessed by Response Evaluation Criteria in Solid Tumors, version 1.1, and overall survival (OS). Objective response rates, 4-year PFS, and OS rates were compared in the following patient subgroups: BRAF WT vs BRAF V600E/K-mutant melanoma and BRAF V600E/K-mutant melanoma with vs without previous treatment with BRAFi with or without MEKi therapy.

Results

The overall study population (N = 1558) included 944 men (60.6%) and 614 women (39.4%). The mean (SD) age was 60.0 years (14.0). The ORR was 38.3% (596/1558), 4-year PFS rate was 22.0%, and 4-year OS rate was 36.9%. For patients with BRAF WT (n = 1124) and BRAF V600E/K-mutant melanoma (n = 434), ORR was 39.8% (n = 447) and 34.3% (n = 149), 4-year PFS rate was 22.9% and 19.8%, and 4-year OS rate was 37.5% and 35.1%, respectively. Patients with BRAF V600E/K-mutant melanoma who had (n = 271) vs had not (n = 163) previously received BRAFi with or without MEKi therapy had baseline characteristics with worse prognosis; ORR was 28.4% (n = 77) and 44.2% (n = 72), 4-year PFS rate was 15.2% and 27.8%, and 4-year OS rate was 26.9% and 49.3%, respectively.

Conclusions and Relevance

Results of this subgroup analysis support the use of pembrolizumab for treatment of advanced melanoma regardless of BRAF V600E/K mutation status or receipt of prior BRAFi with or without MEKi therapy.

The State of Melanoma: Emergent Challenges and Opportunities

Five years ago, the Melanoma Research Foundation (MRF) conducted an assessment of the challenges and opportunities facing the melanoma research community and patients with melanoma. Since then, remarkable progress has been made on both the basic and clinical research fronts. However, the incidence, recurrence, and death rates for melanoma remain unacceptably high and significant challenges remain. Hence, the MRF Scientific Advisory Council and Breakthrough Consortium, a group that includes clinicians and scientists, reconvened to facilitate intensive discussions on thematic areas essential to melanoma researchers and patients alike, prevention, detection, diagnosis, metastatic dormancy and progression, response and resistance to targeted and immune-based therapy, and the clinical consequences of COVID-19 for patients with melanoma and providers. These extensive discussions helped to crystalize our understanding of the challenges and opportunities facing the broader melanoma community today. In this report, we discuss the progress made since the last MRF assessment, comment on what remains to be overcome, and offer recommendations for the best path forward.

407 Preliminary safety, pharmacokinetics/pharmacodynamics, and antitumor activity of XmAb20717, a PD-1 x CTLA-4 bispecific antibody, in patients with advanced solid tumors

Background

XmAb20717 is a humanized bispecific monoclonal antibody that simultaneously targets PD-1 and CTLA-4. We report preliminary data from an ongoing, multicenter, Phase 1 study investigating the safety/tolerability, pharmacokinetics/pharmacodynamics, and clinical activity (RECIST 1.1) of XmAb20717 in patients with selected advanced solid tumors.

Methods

A 3+3 dose-escalation design was used to establish a maximum tolerated (MTD)/recommended dose for evaluation in parallel expansion cohorts, including melanoma, renal cell carcinoma, non-small cell lung cancer (NSCLC), prostate cancer, and a basket of tumor types without an FDA-approved checkpoint inhibitor (CI; n≤20 each). XmAb20717 was administered as an infusion on Days 1 and 15 of each 28-day cycle.

Results

As of 08Jul2020, 109 patients had been treated (table 1), and 30 were continuing treatment. In escalation, 6 dose levels (0.15–10.0 mg/kg) were evaluated (n=34); an MTD was not established. Expansion cohorts were initiated at 10 mg/kg (n=72), and a 15 mg/kg escalation cohort was added (n=3). T-cell proliferation was noted in peripheral blood at doses as low as 3 mg/kg and was highest at 10 mg/kg. At this dose, consistent proliferation of CD8+ and CD4+ T cells was observed, indicative of dual PD-1 and CTLA-4 checkpoint blockade (figure 1). Paired pre- and post-dosing biopsies showed increased intratumoral T-cell infiltration and IFN-response signatures following treatment. Grade 3/4 treatment-related adverse events (TRAEs) reported for ≥3 patients included rash (13%), transaminase elevations (7%), lipase increased (4% [2% with amylase increased]), and acute kidney injury (3%), all considered immune-related. There were 2 Grade 5 TRAEs: immune-mediated pancreatitis (in the presence of pancreatic metastases) and immune-mediated myocarditis (Grade 4) that contributed to respiratory failure. A complete response was reported as the best overall response for 1 patient (melanoma); partial responses were reported for 5 patients (2 melanoma, 2 NSCLC, 1 ovarian). The objective response rate was 13% overall and 21% at 10 mg/kg (6/46 and 6/29 evaluable patients, respectively). All responders had prior CI exposure. Responses were observed only at 10 mg/kg and, within the 10 mg/kg group, appeared to correlate with higher peak serum concentration and area under the curve.

Abstract 407 Table 1

Demographics and baseline characteristics

Abstract 407 Figure 1

Mean change from baseline in percentage of Ki67+ T–cell expression in peripheral blood during first two cycles of XmAb20717

Conclusions

XmAb20717 induced T-cell proliferation in peripheral blood consistent with dual-checkpoint blockade. Preliminary data indicate XmAb20717 was generally well-tolerated and associated with evidence of antitumor activity in CI-pretreated patients with various types of advanced solid tumors.

Trial Registration

NCT03517488

Ethics Approval

The study was approved by each institution’s IRB.

Regulatory T cell control of systemic immunity and immunotherapy response in liver metastasis

Patients with cancer with liver metastasis demonstrate significantly worse outcomes than those without liver metastasis when treated with anti-PD-1 immunotherapy. The mechanism of liver metastases-induced reduction in systemic antitumor immunity is unclear. Using a dual-tumor immunocompetent mouse model, we found that the immune response to tumor antigen presence within the liver led to the systemic suppression of antitumor immunity. The immune suppression was antigen specific and associated with the coordinated activation of regulatory T cells (T_regs) and modulation of intratumoral CD11b⁺ monocytes. The dysfunctional immune state could not be reversed by anti-PD-1 monotherapy unless T_reg cells were depleted (anti-CTLA-4) or destabilized (EZH2 inhibitor). Thus, this study provides a mechanistic understanding and rationale for adding T_reg and CD11b⁺ monocyte targeting agents in combination with anti-PD-1 to treat patients with cancer with liver metastasis.

Prognostic Gene Expression Profiling in Cutaneous Melanoma: Identifying the Knowledge Gaps and Assessing the Clinical Benefit

Importance

Use of prognostic gene expression profile (GEP) testing in cutaneous melanoma (CM) is rising despite a lack of endorsement as standard of care.

Objective

To develop guidelines within the national Melanoma Prevention Working Group (MPWG) on integration of GEP testing into the management of patients with CM, including (1) review of published data using GEP tests, (2) definition of acceptable performance criteria, (3) current recommendations for use of GEP testing in clinical practice, and (4) considerations for future studies.

Evidence Review

The MPWG members and other international melanoma specialists participated in 2 online surveys and then convened a summit meeting. Published data and meeting abstracts from 2015 to 2019 were reviewed.

Findings

The MPWG members are optimistic about the future use of prognostic GEP testing to improve risk stratification and enhance clinical decision-making but acknowledge that current utility is limited by test performance in patients with stage I disease. Published studies of GEP testing have not evaluated results in the context of all relevant clinicopathologic factors or as predictors of regional nodal metastasis to replace sentinel lymph node biopsy (SLNB). The performance of GEP tests has generally been reported for small groups of patients representing particular tumor stages or in aggregate form, such that stage-specific performance cannot be ascertained, and without survival outcomes compared with data from the American Joint Committee on Cancer 8th edition melanoma staging system international database. There are significant challenges to performing clinical trials incorporating GEP testing with SLNB and adjuvant therapy. The MPWG members favor conducting retrospective studies that evaluate multiple GEP testing platforms on fully annotated archived samples before embarking on costly prospective studies and recommend avoiding routine use of GEP testing to direct patient management until prospective studies support their clinical utility.

Conclusions and Relevance

More evidence is needed to support using GEP testing to inform recommendations regarding SLNB, intensity of follow-up or imaging surveillance, and postoperative adjuvant therapy. The MPWG recommends further research to assess the validity and clinical applicability of existing and emerging GEP tests. Decisions on performing GEP testing and patient management based on these results should only be made in the context of discussion of testing limitations with the patient or within a multidisciplinary group.

Abstract 1031: Liver metastasis mediated control of distant tumor-specific immunity and response to checkpoint immunotherapy

Background: PD-1 blockade achieves objective responses in 30-55% of melanoma patients, but there remain 45-70% of patients where it is ineffective, either as a single agent or in combination with anti-CTLA-4. We lack salvage strategies for this population and a mechanistic understanding of checkpoint inhibitor refractory melanoma. Previously, we reported that patients with liver metastasis have worse response rate and survival than those without liver metastasis despite treatment with checkpoint immunotherapy and cutaneous biopsy samples from patients with liver metastasis have significantly less activated tumor-infiltrating lymphocytes (TILs) than those with metastasis elsewhere. However, the mechanism of how liver metastasis influences the systemic antitumor immune response in this context is unclear. We hypothesize that tumor antigen-specific tolerance can be induced when metastatic cells invade the liver, resulting in reduced systemic antitumor immunity and immunotherapy resistance.

Results: In this study, we developed a syngeneic two-site tumor animal model in which tumor cells are injected simultaneously into a subcutaneous (SQ) site and into the liver or other organ sites of wild-type C57BL/6 mice to investigate the unique effects of the intrahepatic tumor on antitumor immunity at a distant site. We found that the presence of tumor or tumor antigen within the liver, as opposed to other organs, reduced systemic antitumor immunity and effector T cell function that is evident at the distant SQ site. Tetramer-based flow cytometry and single cell-RNAseq analysis were done on the TILs within the SQ site and the results suggest that tumor-specific CD8 T cells were preferentially dysfunctional but not sequestered by the liver or clonally deleted, with reduced expression of activation markers and effector cytokines (ICOS, CTLA-4, IFNγ, and TNFα). Collectively, the data suggest a liver and antigen-specific immunoregulatory process mediated by the coordinated activation of Foxp3+ regulatory T cells (with increased expression of CTLA-4 and ICOS) and significant changes in the non-T cell immune composition at the distant SQ site in the liver-tumor bearing mice. Genetic studies using a mouse strain expressing the diphtheria toxin receptor under the control of Foxp3 (Foxp3-DTR) with or without the systemic depletion of Tregs revealed that in the absence of Tregs, there was no difference in the distal immunity against the SQ tumor between mice with and without experimental liver metastasis. Finally, we found that this form of systemic antitumor effector T cell dysfunction was not reversed by anti-PD-1 monotherapy but rather by combination therapy with the deletion (anti-CTLA-4) or destabilization (EZH2 inhibitor) of Tregs, suggesting a distinct regulatory mechanism contributing to anti-PD-1 resistance in the setting of liver metastasis that could be overcome to achieve complete tumor regression at both sites.

Conclusion: Our results reveal a novel mechanism of checkpoint inhibitor resistance and suggest a strategy to improve the outcome of immunotherapy treatments for stage IV cancer patients with liver metastasis.

Citation Format: James C. Lee, Sadaf Mehdizadeh, Arabella Young, Jennifer Bridge, Ilgiz A. Mufazalov, Adil Daud, Jeffrey A. Bluestone. Liver metastasis mediated control of distant tumor-specific immunity and response to checkpoint immunotherapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1031.

Abstract CT013: SWOG S1320: Improved progression-free survival with continuous compared to intermittent dosing with dabrafenib and trametinib in patients with BRAF mutated melanoma

Background: BRAF and MEK inhibitors yield objective responses in the majority of BRAFV600E/K mutant melanoma patients, but acquired resistance limits response durations. Preclinical data suggests that intermittent dosing of these agents may delay acquired resistance by deselecting tumor cells that grow optimally in the presence of these agents. S1320 is a randomized phase 2 clinical trial designed to determine whether intermittent versus continuous dosing of dabrafenib and trametinib improves progression-free survival (PFS) in patients with advanced BRAFV600E/K melanoma.

Methods: All patients received continuous dabrafenib and trametinib for 8-weeks after which non-progressing patients were randomized to receive either continuous treatment or intermittent dosing of both drugs on a 3-week-off, 5-week-on schedule. Unscheduled treatment interruptions of both drugs for > 14 days were not permitted. Responses were assessed using RECIST v1.1 at 8-week intervals scheduled to coincide with on-treatment periods for patients on the intermittent dosing arm. Adverse events were assessed using CTCAE v4 monthly. The design assumed exponential PFS with a median of 9.4 months using continuous dosing, 206 eligible patients and 156 PFS events. It had 90% power with a two-sided α = 0.2 to detect a change to a median with an a priori hypothesis that intermittent dosing would improve the median PFS to 14.1 months using a Cox model stratified by the randomization stratification factors.

Results: 242 patients were treated and 206 patients without disease progression after 8 weeks were randomized, 105 to continuous and 101 to intermittent treatment. 70% of patients had not previously received immune checkpoint inhibitors. There were no significant differences between groups in terms of baseline patient characteristics. The median PFS was statistically significantly longer, 9.0 months from randomization, with continuous dosing vs. 5.5 months from randomization with intermittent dosing (p = 0.064). There was no difference in overall survival between groups (median OS = 29.2 months in both arms p = 0.93) at a median follow up of 2 years. 77% of patient treated continuously discontinued treatment due to disease progression vs. 84% treated intermittently (p = 0.34).

Conclusions: Continuous dosing with the BRAF and MEK inhibitors dabrafenib and trametinib yields superior PFS compared with intermittent dosing.

Support: NIH/NCI grants CA180888, CA180819, CA180820

Citation Format: Alain Algazi, Megan Othus, Adil Daud, Roger Lo, Janice Mehnert, Thach-Giao Truong, Robert Conry, Kari Kendra, Gary Doolittle, Joseph I. Clark, Michael Messino, Dennis F. Moore, Christopher Lao, Bryan A. Faller, Rangaswamy Govindarajan, Amy Harker-Murray, Luke Dreisbach, James Moon, Kenneth Grossman, Antoni Ribas. SWOG S1320: Improved progression-free survival with continuous compared to intermittent dosing with dabrafenib and trametinib in patients with BRAF mutated melanoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT013.

Exhausted T cell signature predicts immunotherapy response in ER-positive breast cancer

Responses to immunotherapy are uncommon in estrogen receptor (ER)-positive breast cancer and to date, lack predictive markers. This randomized phase II study defines safety and response rate of epigenetic priming in ER-positive breast cancer patients treated with checkpoint inhibitors as primary endpoints. Secondary and exploratory endpoints included PD-L1 modulation and T-cell immune-signatures. 34 patients received vorinostat, tamoxifen and pembrolizumab with no excessive toxicity after progression on a median of five prior metastatic regimens. Objective response was 4% and clinical benefit rate (CR + PR + SD > 6 m) was 19%. T-cell exhaustion (CD8⁺ PD-1⁺/CTLA-4⁺) and treatment-induced depletion of regulatory T-cells (CD4⁺ Foxp3⁺/CTLA-4⁺) was seen in tumor or blood in 5/5 patients with clinical benefit, but only in one non-responder. Tumor lymphocyte infiltration was 0.17%. Only two non-responders had PD-L1 expression >1%. This data defines a novel immune signature in PD-L1-negative ER-positive breast cancer patients who are more likely to benefit from immune-checkpoint and histone deacetylase inhibition (NCT02395627).

Phase II single-arm multi-center study of adjuvant ipilimumab in combination with nivolumab in subjects with high-risk ocular melanoma

TPS10089

Background: Treatment of primary ocular melanoma is often very effective, with local recurrence rates of < 5%. However, distant recurrence is as high as 50% depending on features of the primary tumor. These data emphasize the need for effective adjuvant therapy for patients with locally treated ocular melanoma. Several adjuvant treatments have been developed for patients with high-risk cutaneous melanoma, including ipilimumab and nivolumab monotherapies and an ongoing trial is exploring the nivolumab/ipilimumab combination (CA209-915), but patients with high-risk ocular melanomas have been excluded from these trials. As yet there is no approved adjuvant treatment for high-risk ocular melanoma patients. Methods: We are conducting a Phase II single-arm multi-center study of adjuvant ipilimumab in combination with nivolumab in subjects with high-risk ocular melanoma. This study aims to generate efficacy and safety data for adjuvant this regimen in patients with locally treated high-risk ocular melanoma with 3-year risk of relapse > 50%. The primary endpoint is 3-year relapse-free survival rate. Secondary endpoints are median relapse-free survival, median overall survival, 3-year overall survival rate and safety. All patients will receive nivolumab 240mg IV every 2 weeks plus ipilimumab 1mg/kg IV every 6 weeks. Subjects may receive up to 25 doses of nivolumab and 8 doses of ipilimumab. The accrual goal is 50 patients across all participating institutions. Subjects treated in this study will be matched with controls selected from a contemporaneously collected OM registry, “contemporaneous control” in order to better assess efficacy. Control subjects will be from institutions not participating in this trial, will otherwise meet the trial eligibility criteria and will be further matched with trial participants for various demographic and risk factors to the extent possible. The study is enrolling in 6 comprehensive cancer centers in the US. Clinical trial information: NCT3528408.

Prospective investigation of immunotherapy-induced fatigue by rest and stress echocardiography

e24060

Background: Immune checkpoint inhibitors (ICI) effect durable responses in cancer patients (pts). Myocarditis is rare but fatigue is commonly reported, and whether ICI-induced fatigue is due to subclinical cardiac toxicity is unknown. We hypothesized that pts on ICI develop changes on rest and stress echocardiogram (echo) that correlate with fatigue. Methods: A prospective observational study was performed to monitor cardiac function in pts receiving ICI. Our cohort consisted of pts (n = 10) with stage III/IV melanoma, ECOG 0-1, deemed safe to exercise, without unstable cardiac symptoms. ICI-naïve pts received anti-PD1 alone or in combination with anti-CTLA-4, in adjuvant or metastatic setting. Rest transthoracic echo and dynamic staged exercise stress echo testing was conducted at baseline (prior to ICI) and at 3 and 6 months (mo) following ICI. Various echo parameters at rest and stress were compared. irAEs were detailed and surveys administered at baseline and post-follow up. Results: 10 pts (9 men, mean age 56 yrs) completed baseline cardiac testing of whom 7 completed follow up testing at 6 mo (6 anti-PD1 monotherapy, 1 metastatic combination therapy). Of these 7 pts, 5 (71%) reported increased fatigue per CTCAE at 3 or 6 mo follow up and all 7 had irAEs (3 rash, 1 colitis, 1 diarrhea, 1 hypophysitis, 1 arthralgia, 1 xerostomia). Among resting echo parameters, left ventricular outflow tract velocity time integral (LVOT VTI) was significantly reduced at 6 mo compared to baseline (22.6 ± 3.4 vs 20.0 ± 2.5, p = 0.0047), albeit still within normal range. No other resting echo parameters changed. Among exercise echo parameters, there was no difference in METs achieved, time of exercise, blood pressure or heart rate between time points. Of note, of 7 subjects who completed 6 mo testing, 2 (29%) were unable to achieve previous peak stage of exercise during testing. Conclusions: Though no echo parameter significantly correlating with fatigue was reported, nearly one-third of a small cohort of pts were unable to achieve peak exercise 6 mo after starting ICI. This combined with the statistical reduction in LVOT VTI suggests functional limitation and warrants further study. Post-follow up surveys are pending and may further inform issues important in ICI survivorship. [Table: see text]

Long-term survival from pembrolizumab (pembro) completion and pembro retreatment: Phase III KEYNOTE-006 in advanced melanoma

10013

Background: 5-year follow-up of the phase 3 KEYNOTE-006 study (NCT01866319) showed pembro improved OS vs ipilimumab (ipi) in patients (pts) with advanced melanoma. 3-y OS rate from pembro completion for pts who completed 2 y of pembro was 93.8%. Results with 8 mo of additional follow-up are presented to inform clinical care. Methods: Eligible pts with ipi-naive advanced melanoma, ≤1 prior therapy for BRAF-mutant disease, and ECOG PS 0 or 1 were randomized to pembro 10 mg/kg Q2W or Q3W for ≤2 y or ipi 3 mg/kg Q3W for 4 doses. Pts discontinuing pembro with CR, PR, or SD after ≥94 weeks were considered pts with 2-y pembro. Pts who stopped pembro with SD, PR or CR could receive ≤12 mo of additional pembro (2nd course) upon disease progression if still eligible. ORR was assessed per immune-related response criteria by investigator review. OS was estimated using the Kaplan-Meier method. Pembro arm data were pooled. Post hoc ITT efficacy analyses are shown. Results: Median follow-up from randomization to data cutoff (Jul 31, 2019) was 66.7 mo in the pembro and 66.9 mo in the ipi arms. OS outcomes are shown in Table. For the 103 pts with 2-y pembro (30 CR, 63 PR, 10 SD), median follow-up from completion was 42.9 mo (95% CI, 39.9-46.3).Median DOR was not reached. 36-mo OS from pembro completion was 100% (95% CI, 100.0-100.0) for pts with CR, 94.8% (95% CI, 84.7-98.3) for pts with PR, and 66.7% (95% CI, 28.2-87.8) for pts with SD. 15 pts received 2nd-course pembro; BOR in 1st course was 6 CR, 6 PR, and 3 SD. Median time from end of 1st course to start of 2ndcourse was 24.5 mo (range, 4.9-41.4). Median follow-up in pts who received 2nd-course pembro was 25.3 mo (range, 3.5-39.4). Median duration of 2nd-course pembro was 8.3 mo (range, 1.4-12.6). BOR on 2ndcourse was 3 CR, 5 PR (ongoing responses, 7 pts), 3 SD (ongoing, 2 pts), and 2 PD (1 death); 2 pts pending. Conclusions: Pembro improves the long-term survival vs ipi in pts with advanced melanoma, with all pts who completed therapy in CR still alive at 5 years. Retreatment with pembro at progression in pts who stopped at SD or better can provide additional clinical benefit in a majority of pts. Clinical trial information: NCT01866319. [Table: see text]

Association of prior immune checkpoint blockade (ICB) with longer progression-free survival (PFS) in patients treated with intermittent versus continuous dabrafenib and trametinib: A post-hoc analysis of S1320

10039

Background: S1320 is a phase 2 randomized clinical trial presented at the 2020 AACR Annual Meeting in April demonstrating that continuous dosing of dabrafenib and trametinib yields longer PFS than intermittent dosing of these agents in patients with BRAFV600E/K melanoma. Here we look at the association between prior exposure to ICB and PFS in patients randomized to either intermittent or continuous dosing on S1320. Methods: Patients without disease progression after 8 weeks of dabrafenib and trametinib were randomized 1:1 to proceed with intermittent therapy (3-week-off, 5-week-on) or to stay on the continuous daily dosing schedule. The design called for 206 randomized patients with the primary outcome of PFS. Response assessments were made using RECIST v1.1 at 8-week intervals. A post-hoc analysis assessed differences in PFS in the pool of all randomized patients based on prior exposure to anti-PD1 antibodies, a randomization stratification factor. Kaplan-Meier estimates and multivariable Cox regression models (controlling for pre-randomization age, Zubrod performance status, LDH, unknown primary, M-Stage) were used to evaluate the association between this stratification factor and PFS. Results: Of 242 patients treated on study, 105 were randomized to continuous dosing, 101 to intermittent dosing, and 36 were not randomized due to disease progression at 8 weeks or other factors. 37% of the 242 enrolled and 37% of the 206 randomized patients had previously been treated with ICB. Among all randomized patients, there were no differences in baseline characteristics comparing patients with and without prior immune checkpoint inhibitor exposure: age median 62 vs 59, LDH elevation 37% vs 39%,, stage IVB/C 73% vs 64%, Zubrod performance status 0, 57% vs 58%. PFS was longer in patients with prior ICB exposure (hazard ratio = 0.60, 95% confidence interval 0.41,-0.98, median = 6 vs 9 months from randomization, 8 vs 11 months from starting treatment). There was no difference in the association between prior ICB exposure and PFS between arms (interaction p-value = 0.62). Conclusions: In patients without early progression on dabrafenib and trametinib, PFS was longer with prior to exposure to ICB . Although the groups had similar baseline characteristics and rates of randomization, these results could still be influenced by non-controlled factors influencing clinicians’ decisions to start a patient on immune versus targeted therapy. Clinical trial information: NCT02196181.

Regulatory T cell control of systemic tumor-specific immunity and response to checkpoint immunotherapy response in liver metastasis

A significant number of metastatic melanoma patients have disease progression despite checkpoint inhibitor therapy. We lack salvage strategies for this population and a mechanistic understanding of checkpoint inhibitor refractory disease. Previously, we reported that patients with liver metastasis have worse response rate and survival than those without liver metastasis despite treatment with checkpoint immunotherapy, but how liver metastasis can influence the antitumor immune response in this context is unclear. We hypothesize that tumor antigen-specific tolerance can be induced in the context of liver metastasis, resulting in therapy resistance.

In this study, we developed a syngeneic two-site tumor model in which tumor cells are injected simultaneously into a subcutaneous (SQ) site and into the liver or other organ sites of B6 mice to study the effects of the intrahepatic tumor on antitumor immunity at a distant site. We found that the presence of tumor or tumor antigen within the liver reduced systemic antigen-specific effector T cell function. Tetramer and sc-RNAseq studies suggest a liver and antigen-specific immunoregulatory process associated with the activation of regulatory T cells and the remodeling of innate immune cells. Importantly, this systemic dysfunctional immune state was not reversed by anti-PD-1 monotherapy but rather by deleting (anti-CTLA-4) or destabilizing (EZH2 inhibitor) intratumoral Tregs, suggesting a distinct regulatory mechanism contributing to anti-PD-1 resistance that could be overcome to achieve complete tumor regression at all sites.

Our results reveal a novel mechanism of checkpoint inhibitor resistance and suggest a strategy to improve the outcome for patients with liver metastasis.

O85 Durable responses in anti-PD-1 refractory melanoma following intratumoral injection of a toll-like receptor 9 (TLR9) agonist, CMP-001, in combination with pembrolizumab

Background

Intratumoral (IT) injection of CMP-001, a CpG-A TLR9 agonist packaged within a virus-like particle, is designed to activate tumor-associated plasmacytoid dendritic cells, inducing an interferon-rich tumor microenvironment and anti-tumor CD8+ T cell responses.

Methods

CMP-001-001 is an ongoing Phase 1b trial evaluating the safety and efficacy of CMP-001 in combination with pembrolizumab (Part 1; N = 144) or alone (Part 2; N = 23) in patients with advanced melanoma resistant to prior anti-PD-1 therapy (Tables 1). CMP-001 is administered IT into accessible lesion(s) either with, or without on-site saline dilution (table 1), and response assessed by RECIST v1.1. Monotherapy patients who progress can be rolled over onto combination therapy and continue on study. Baseline and on-therapy serum is analyzed for cytokines, and immunohistochemistry and RNA-Seq are performed on available tumor biopsies.

Abstract O85 Table 1

Advanced anti-PD-1 Refractory melanoma patient population by treatment allocation

Results

Adverse events (AEs) attributed to CMP-001 in combination with pembrolizumab or as monotherapy consisted predominately of transient low-Grade flu-like symptoms and injection site reactions: Grade 3+ related AEs were reported in 33% of patients treated with combination therapy and 22% of patients with monotherapy.

The Objective Response Rate (ORR) with undiluted CMP-001 in combination with pembrolizumab was 24% (18/75; 95% confidence interval: 15%-35% (table 1); on-site dilution of CMP-001 was associated with a substantial decrease in ORR to 12% (7/61; 95% confidence interval: 5%-22% (table 1). Three additional patients had a delayed partial response after an initial period of disease progression. Anti-tumor response was comparable between injected and uninjected lesions. The median duration of response to combination therapy has not been reached. The ORR to CMP-001 monotherapy was 22% (5/23; 95% confidence interval: 7%-44% (table 1); time from last anti-PD-1 therapy before CMP-001 was 1.5 to >20 months in responders; 3 of the patients responding to CMP-001 monotherapy achieved PR at the first evaluation, but progressed by the second evaluation.

Serum and tumor biopsy translational studies in the patients receiving combination therapy supported the proposed mechanism of TLR9 activation and identified a possible association between induction of serum CXCL10 and response.

Conclusions

IT CMP-001 alone and in combination with pembrolizumab appears well tolerated, can reverse resistance to anti-PD-1 therapy, and can produce deep and durable clinical responses in patients with advanced melanoma.

Ethics Approval

CMP-001-001 was centrally approved by the WCG-WIRB, WIRB approval tracking number 20152597.

Regulatory T cells use arginase 2 to enhance their metabolic fitness in tissues

Distinct subsets of Tregs reside in nonlymphoid tissues where they mediate unique functions. To interrogate the biology of tissue Tregs in human health and disease, we phenotypically and functionally compared healthy skin Tregs with those in peripheral blood, inflamed psoriatic skin, and metastatic melanoma. The mitochondrial enzyme, arginase 2 (ARG2), was preferentially expressed in Tregs in healthy skin, increased in Tregs in metastatic melanoma, and reduced in Tregs from psoriatic skin. ARG2 enhanced Treg suppressive capacity in vitro and conferred a selective advantage for accumulation in inflamed tissues in vivo. CRISPR-mediated deletion of this gene in primary human Tregs was sufficient to skew away from a tissue Treg transcriptional signature. Notably, the inhibition of ARG2 increased mTOR signaling, whereas the overexpression of this enzyme suppressed it. Taken together, our results suggest that Tregs express ARG2 in human tissues to both regulate inflammation and enhance their metabolic fitness.

Extended 5-Year Follow-up Results of a Phase Ib Study (BRIM7) of Vemurafenib and Cobimetinib in BRAF-Mutant Melanoma

PURPOSE

To report the 5-year overall survival (OS) landmark and the long-term safety profile of vemurafenib plus cobimetinib (BRAF plus MEK inhibition, respectively) in the BRIM7 study.

PATIENTS AND METHODS

This phase Ib, dose-finding, and expansion study evaluated combination treatment with vemurafenib and cobimetinib in two cohorts of patients with advanced BRAF ^V600-mutated melanoma: patients who were BRAF inhibitor (BRAFi)-naïve (n = 63) or patients who had progressed on prior treatment with BRAFi monotherapy [vemurafenib monotherapy-progressive disease (PD); n = 66]. Patients in the dose-escalation phase received vemurafenib at 720 or 960 mg twice daily in combination with cobimetinib at 60, 80, or 100 mg/d for 14 days on/14 days off, 21 days on/7 days off, or continuously. Two regimens were selected for expansion: vemurafenib (720 and 960 mg twice daily) and cobimetinib (60 mg/d 21/7).

RESULTS

Median OS was 31.8 months [95% confidence interval (CI), 24.5-not estimable] in the BRAFi-naïve cohort. The landmark OS rate plateaued at 39.2% at years 4 and 5 of follow-up. In the vemurafenib monotherapy-PD cohort, the median OS was 8.5 months (95% CI, 6.7-11.1), and the landmark OS rate plateaued at 14.0% from 3 years of follow-up. No increase was observed in the frequency and severity of adverse events with long-term follow-up. No new toxicities were detected, and there was no increase in the frequency of symptomatic MEK inhibitor class-effect adverse events.

CONCLUSIONS

A subset of patients with advanced BRAF ^V600-mutated melanoma treated with a combination regimen of vemurafenib and cobimetinib achieve favorable long-term outcomes.

An analysis of genetic heterogeneity in untreated cancers

Genetic intratumoural heterogeneity is a natural consequence of imperfect DNA replication. Any two randomly selected cells, whether normal or cancerous, are therefore genetically different. Here, we review the different forms of genetic heterogeneity in cancer and re-analyse the extent of genetic heterogeneity within seven types of untreated epithelial cancers, with particular regard to its clinical relevance. We find that the homogeneity of predicted functional mutations in driver genes is the rule rather than the exception. In primary tumours with multiple samples, 97% of driver-gene mutations in 38 patients were homogeneous. Moreover, among metastases from the same primary tumour, 100% of the driver mutations in 17 patients were homogeneous. With a single biopsy of a primary tumour in 14 patients, the likelihood of missing a functional driver-gene mutation that was present in all metastases was 2.6%. Furthermore, all functional driver-gene mutations detected in these 14 primary tumours were present among all their metastases. Finally, we found that individual metastatic lesions responded concordantly to targeted therapies in 91% of 44 patients. These analyses indicate that the cells within the primary tumours that gave rise to metastases are genetically homogeneous with respect to functional driver-gene mutations, and we suggest that future efforts to develop combination therapies have the potential to be curative.

Pembrolizumab versus ipilimumab in advanced melanoma (KEYNOTE-006): post-hoc 5-year results from an open-label, multicentre, randomised, controlled, phase 3 study

BACKGROUND

Pembrolizumab improved progression-free survival and overall survival versus ipilimumab in patients with advanced melanoma and is now a standard of care in the first-line setting. However, the optimal duration of anti-PD-1 administration is unknown. We present results from 5 years of follow-up of patients in KEYNOTE-006.

METHODS

KEYNOTE-006 was an open-label, multicentre, randomised, controlled, phase 3 study done at 87 academic institutions, hospitals, and cancer centres in 16 countries. Patients aged at least 18 years with Eastern Cooperative Oncology Group performance status of 0 or 1, ipilimumab-naive histologically confirmed advanced melanoma with known BRAF^V600 status and up to one previous systemic therapy were randomly assigned (1:1:1) to intravenous pembrolizumab 10 mg/kg every 2 weeks or every 3 weeks or four doses of intravenous ipilimumab 3 mg/kg every 3 weeks. Treatments were assigned using a centralised, computer-generated allocation schedule with blocked randomisation within strata. Exploratory combination of data from the two pembrolizumab dosing regimen groups was not protocol-specified. Pembrolizumab treatment continued for up to 24 months. Eligible patients who discontinued pembrolizumab with stable disease or better after receiving at least 24 months of pembrolizumab or discontinued with complete response after at least 6 months of pembrolizumab and then progressed could receive an additional 17 cycles of pembrolizumab. Co-primary endpoints were overall survival and progression-free survival. Efficacy was analysed in all randomly assigned patients, and safety was analysed in all randomly assigned patients who received at least one dose of study treatment. Exploratory assessment of efficacy and safety at 5 years' follow-up was not specified in the protocol. Data cutoff for this analysis was Dec 3, 2018. Recruitment is closed; the study is ongoing. This study is registered with ClinicalTrials.gov, number NCT01866319.

FINDINGS

Between Sept 18, 2013, and March 3, 2014, 834 patients were enrolled and randomly assigned to receive pembrolizumab (every 2 weeks, n=279; every 3 weeks, n=277), or ipilimumab (n=278). After a median follow-up of 57·7 months (IQR 56·7-59·2) in surviving patients, median overall survival was 32·7 months (95% CI 24·5-41·6) in the combined pembrolizumab groups and 15·9 months (13·3-22·0) in the ipilimumab group (hazard ratio [HR] 0·73, 95% CI 0·61-0·88, p=0·00049). Median progression-free survival was 8·4 months (95% CI 6·6-11·3) in the combined pembrolizumab groups versus 3·4 months (2·9-4·2) in the ipilimumab group (HR 0·57, 95% CI 0·48-0·67, p<0·0001). Grade 3-4 treatment-related adverse events occurred in 96 (17%) of 555 patients in the combined pembrolizumab groups and in 50 (20%) of 256 patients in the ipilimumab group; the most common of these events were colitis (11 [2%] vs 16 [6%]), diarrhoea (ten [2%] vs seven [3%]), and fatigue (four [<1%] vs three [1%]). Any-grade serious treatment-related adverse events occurred in 75 (14%) patients in the combined pembrolizumab groups and in 45 (18%) patients in the ipilimumab group. One patient assigned to pembrolizumab died from treatment-related sepsis.

INTERPRETATION

Pembrolizumab continued to show superiority over ipilimumab after almost 5 years of follow-up. These results provide further support for use of pembrolizumab in patients with advanced melanoma.

FUNDING

Merck Sharp & Dohme.

Abstract CT188: 5-year survival and other long-term outcomes from KEYNOTE-006 study of pembrolizumab (pembro) for ipilimumab (ipi)-naive advanced melanoma

Introduction: Pembro significantly improved OS vs ipi in advanced melanoma in the KEYNOTE-006 study (NCT01866319). We present outcomes from the 5-year follow-up of this study−the longest to date in a randomized phase 3 trial of pembro in advanced cancer. Long-term follow-up for pts completing 2 years of pembro and data for pts treated with a second course (2nd course) of pembro are also reported.

Methods: Eligible pts (N=834) were randomly assigned (1:1:1) to pembro 10 mg/kg Q2W or Q3W for up to 2 years or ipi 3 mg/kg Q3W for 4 doses. Eligible pts who completed pembro or stopped for CR and then progressed could receive an additional 12 mo of pembro if they met inclusion criteria. End points included OS and ORR per irRC by investigator review. Pembro completion was defined as discontinuation with CR, PR, or SD after ≥94 weeks of pembro. Results were pooled from the 2 pembro arms.

Results: At data cutoff (Dec 3, 2018), median follow-up of surviving pts was 57.7 mo (range, 0.03-62.1). Median OS (95% CI) was 32.7 mo (24.5-41.6) in the combined pembro arms (n=556) and 15.9 mo (13.3-22.0) in the ipi arm (n=278) (HR, 0.73). Five-year OS rates (95% CI) were estimated to be 38.7% (34.2-43.1) and 31.0% (25.3-36.9), respectively. For pts receiving first-line pembro, median OS (95% CI) was 38.7 mo (27.3-50.7) in the combined pembro arms (n=368) and 17.1 mo (13.8-26.2) in the ipi arm (n=181) (HR, 0.73); 5-year OS rates (95% CI) were estimated to be 43.2% (38.0-48.3) and 33.0% (25.8-40.3), respectively. A total of 103 (18.5%) pts completed 2 years of pembro; median survival follow-up from pembro completion was 34.5 mo; OS rate at 36 mo was 93.8%. Of the 103 pts, 76 were progression-free and 27 had PD. Median time from pembro end to progression was 16.8 mo (range, 0.99-33.9). Thirteen pts received 2nd course pembro; best overall response (BOR) in 1st course was 6 CR, 6 PR, and 1 SD. Median duration of 2nd-course pembro was 9.7 mo; BOR on 2nd course was 3 CR, 4 PR, 3 SD, and 1 PD (response assessment was pending for 2 pts). All 3 pts with 2nd-course CR and 2 of 4 with PR had ongoing response; the remaining 2 pts who had 2nd-course PR subsequently progressed. Four pts discontinued 2nd-course treatment before 12 mo (2 due to PD, 1 due to G2 interstitial pneumonia, and 1 due to physician decision). Six pts had grade1/2 TRAEs during 2nd-course pembro; there were no grade 3/4 TRAEs or deaths.

Conclusions: Pembro continued to show improved OS vs ipi in 5-year follow-up of pts with advanced melanoma with 43.2% estimated to be alive at 5 years versus 33.0% with ipi. Almost one-fifth of pts completed 2 years of pembro, and 93.8% are estimated to be alive 3 years after pembro completion. Second-course pembro treatment was generally well tolerated and provided additional antitumor activity. These results confirm that 2-year pembro is an effective treatment for pts with advanced melanoma.

Citation Format: Caroline Robert, Jacob Schachter, Georgina V. Long, Ana Arance, Jean-Jacques Grob, Laurent Mortier, Adil Daud, Matteo S. Carlino, Catriona McNeil, Michal Lotem, James Larkin, Paul Lorigan, Bart Neyns, Christian U. Blank, Omid Hamid, Teresa M. Petrella, James Anderson, Clemens Krepler, Scott J. Diede, Antoni Ribas. 5-year survival and other long-term outcomes from KEYNOTE-006 study of pembrolizumab (pembro) for ipilimumab (ipi)-naive advanced melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT188.

PTCH1 Mutation in a Patient With Metastatic Undifferentiated Carcinoma With Clear Cell Change

Clear cell basal cell carcinoma (BCC) is an unusual variant of BCC. Its pathogenesis, prognosis, and optimal management remain poorly described due to its rarity. This report presents a 51-year-old man with a history of excised BCC and cutaneous squamous cell carcinomas of the face, with multiple recurrent poorly differentiated carcinomas with clear cell changes of the shoulder for which further classification using conventional histologic means was not possible. His tumor tissue was sent to Foundation Medicine for testing, which revealed a high number of pathogenic genomic alterations, including a mutation inPTCH1. He was diagnosed with dedifferentiated BCC and started on vismodegib. He developed lung metastases while receiving vismodegib, and his disease continued to progress while he was undergoing treatment in a phase I clinical trial. Given the high number of pathogenic alterations suggestive of high tumor mutational burden, immunotherapy was considered and off-label authorization was obtained for treatment with a PD-1 antibody (pembrolizumab). He had a dramatic disease response after 4 infusions of pembrolizumab. Molecular testing was instrumental in determining the correct diagnosis and formulating appropriate treatment options for this patient. Molecular profiling of metastatic BCCs and its subtypes is essential to the development of effective targeted therapies and combination approaches.

Abstract 4217: Tumor mutational burden (TMB), T cell-inflamed gene expression profile (GEP) and PD-L1 are independently associated with response to pembrolizumab (Pembro) in patients with advanced melanoma in the KEYNOTE (KN)-006 study

Background: Biomarkers may aid in identifying pts who can benefit from checkpoint blockade therapies. Biomarkers of response to anti-PD-1 therapy include TMB and inflammatory biomarkers such as PD-L1 expression and T cell-inflamed GEP. Effects of TMB and GEP on clinical outcomes were evaluated for Pembro (anti-PD-1) and Ipi (anti-CTLA-4) monotherapies in the KN-006 study.

Methods: In this phase 3, controlled, open label study, 834 pts were randomized to receive Pembro 10 mg/kg every 2 or 3 wks or 4 doses of Ipi 3 mg/kg every 3 wks. Data were available for analysis of TMB (whole exome sequencing) in 216 pts (Pembro n=151 and Ipi n=65), for GEP (RNA, NanoString nCounter) in 641 pts (Pembro n=461 and Ipi n=180) and 134 pts had both TMB and GEP data available. All pts with TMB data and 458 pts with GEP data had PD-L1 expression data (PD-L1 IHC 22C3 pharmDx, MEL score). Statistical testing was prespecified prior to merging biomarker and clinical outcome data. Relationships between biomarkers and best overall response (BOR) were assessed by logistic regression and by area under the ROC (AUROC) curve; progression free survival (PFS) and overall survival (OS) by Cox proportional hazards regression. Prespecified cutoffs were -0.318 for GEP and 175 (mutations/exome) for TMB. Clinical data cutoff was Dec 04, 2017.

Results: TMB, GEP and PD-L1 MEL were significantly associated with BOR, PFS and OS in the Pembro arm (p&lt;0.050). Response rates to Pembro therapy were greater in pts who had high levels of both TMB ≥175 and GEP ≥-0.318 or TMB ≥175 and PD-L1 MEL ≥2 compared with those with low levels of these biomarkers (54% vs 14% and 51% vs 33%, respectively). TMB, GEP and PD-L1 MEL remained significantly associated with response to Pembro for BOR and PFS, and in general for OS, when assessed in joint models. TMB showed low correlations with GEP (0.14; p=0.057) and PD-L1 (0.22; p=0.001); GEP and PD-L1 were moderately correlated (0.60; p&lt;0.001). In Ipi-treated pts, TMB was not significantly associated with BOR (p=0.428) and trended toward significance for PFS (0.098) and OS (p=0.099); GEP was also not significantly associated with BOR (p=0.188) but was significantly associated with PFS (p=0.012) and OS (p&lt;0.001). AUROCs (95% CI) were 0.64 (0.55, 0.73) and 0.53 (0.35, 0.70) for TMB, and 0.64 (0.59, 0.7) and 0.56 (0.45, 0.67) for GEP with Pembro and Ipi. Note the observed TMB relationship with Ipi is based on an assessment of limited data in that arm and definitive conclusions cannot be made.

Conclusion: TMB and inflammatory biomarkers (GEP and PD-L1) showed statistically significant and independent associations with BOR, PFS and OS in Pembro-treated pts with advanced melanoma. Only GEP showed significant associations with PFS and OS for Ipi, potentially indicating a prognostic value.

Citation Format: Antoni Ribas, Caroline Robert, Jacob Schachter, Georgina V. Long, Ana Arance, Matteo S. Carlino, James Larkin, Andrea L. Webber, Jared Lunceford, Qing Zhao, Razvan Cristescu, Michael Nebozhyn, Chunsheng Zhang, Wendy Blumenschein, Clemens Krepler, Nageatte Ibrahim, Adil Daud, Jean-Jacques Grob. Tumor mutational burden (TMB), T cell-inflamed gene expression profile (GEP) and PD-L1 are independently associated with response to pembrolizumab (Pembro) in patients with advanced melanoma in the KEYNOTE (KN)-006 study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4217.

Response to PD-1 inhibition in early- and late-relapsing cutaneous melanoma

e21038

Background: Up to 45% of stage I-II melanomas will relapse within 5 years, and some relapses occur more than 10 years after surgical resection. Little is known about the differences in tumor characteristics, including immunogenicity, of early- vs. late-relapsing melanoma, or the implication of these differences in response to PD-1 inhibition. Methods: A retrospective cohort study was conducted to compare time from definitive treatment of localized melanoma to relapse with response to pembrolizumab. Patients with prior stage I-II melanoma who relapsed, and then treated with pembrolizumab, were included in the study. Time to relapse was compared with overall response rate. Results: Among the study population, 66 patients initially presented with early stage disease that relapsed within the study period. The median time to relapse was 5 years (range 0.5-33 years, interquartile range 7.25, Q1 = 2, Q2 = 9.25). 9 patients (14%) relapsed within 2 years of surgery; these patients had a higher overall response rate to pembrolizumab than late-relapsing patients with marginal significance (88% vs 50%, p = 0.056). The difference became less significant when patients who relapsed before or after 5 years (70% vs 47%, respectively, p = 0.20), and before or after 10 years (64% vs 45%, p = .31). Conclusions: Patients with early-relapsing melanoma had higher ORR to pembrolizumab than patients with late-relapsing disease, with early relapse defined as earlier than 2 years from definitive surgical intervention. Late relapsing tumors may harbor mechanisms of resistance to immune checkpoint inhibition.

Phase II single-arm multicenter study of adjuvant ipilimumab in combination with nivolumab in subjects with high-risk ocular melanoma

TPS9604

Background: Treatment of primary ocular melanoma is often very effective, with local recurrence rates of < 5%. However, distant recurrence is as high as 50% depending on features of the primary tumor. These data emphasize the need for effective adjuvant therapy for patients with locally treated ocular melanoma. Several adjuvant treatments have been developed for patients with high-risk cutaneous melanoma, including ipilimumab and nivolumab monotherapies and an ongoing trial is exploring the nivolumab/ipilimumab combination (CA209-915), but patients with high-risk ocular melanomas have been excluded from these trials. As yet there is no approved adjuvant treatment for high-risk ocular melanoma patients. Methods: We are conducting a Phase II single-arm multi-center study of adjuvant ipilimumab in combination with nivolumab in subjects with high-risk ocular melanoma. This study aims to generate efficacy and safety data for adjuvant this regimen in patients with locally treated high-risk ocular melanoma with 3-year risk of relapse > 50%. The primary endpoint is 3-year relapse-free survival rate. Secondary endpoints are median relapse-free survival, median overall survival, 3-year overall survival rate and safety. All patients will receive nivolumab 240mg IV every 2 weeks plus ipilimumab 1mg/kg IV every 6 weeks. Subjects may receive up to 25 doses of nivolumab and 8 doses of ipilimumab. The accrual goal is 50 patients across all participating institutions. Subjects treated in this study will be matched with controls selected from a contemporaneously collected OM registry, “contemporaneous control” in order to better assess efficacy. Control subjects will be from institutions not participating in this trial, will otherwise meet the trial eligibility criteria and will be further matched with trial participants for various demographic and risk factors to the extent possible. The study is enrolling in 6 comprehensive cancer centers in the US. Clinical trial information: NCT03528408.

Lenvatinib (len) plus pembrolizumab (pembro) in patients (pts) with advanced melanoma previously exposed to anti–PD-1/PD-L1 agents: Phase 2 LEAP-004 study

TPS9594

Background: Pembro, a PD-1 inhibitor, has shown effective antitumor activity, deep and durable responses, and survival benefit in treatment-naive pts and those with previously treated metastatic melanoma. Len, a potent inhibitor of VEGF receptors 1-3, FGF receptors 1-4, PDGF receptor α, RET, and KIT, combined with a PD-1 inhibitor showed antitumor activity superior to either agent alone in preclinical models of colorectal and lung cancer. Additionally, len plus pembro showed anti-tumor activity and was well-tolerated (24-wk ORR, 47.6%; TRAE: gr 3/4, 67%; gr 5, 0%) in pts with advanced melanoma previously treated with 0-2 therapies in the phase 1b/2 KEYNOTE-146 trial. The efficacy and safety of len plus pembro combination therapy will be evaluated in an open-label, phase 2 trial of pts with advanced melanoma that progressed on PD-1/PD-L1 inhibitor therapy (NCT03776136). Methods: Key inclusion criteria: age ≥18 years, histologically/cytologically confirmed unresectable stage III-IV melanoma that progressed (per iRECIST) within 12 weeks of last dose of an approved PD-1/PD-L1 inhibitor therapy (≥2 doses as monotherapy or combined with other therapies), measurable disease, ECOG PS 0/1, no active autoimmune disease, and adequate organ function. Pts must provide a baseline tumor sample. Pts will receive len 20 mg/day orally plus pembro 200 mg IV Q3W for approximately 2 years (35 doses of pembro), after which they may receive len alone until PD or unacceptable toxicity. Response will be assessed per RECIST v1.1 based on blinded independent central review (BICR) Q9W until week 54, Q12W until week 102, and Q24W thereafter. Pts with CR may discontinue treatment after ≥24 weeks of therapy; eligible pts may continue treatment beyond initial RECIST- or iRECIST-defined PD. AEs will be assessed throughout treatment and for 90 days (120 days for serious AEs) after last dose and graded per NCI CTCAE v4.0. Pts will be followed-up for survival status Q12W. The primary efficacy end point is ORR per modified RECIST v1.1 (BICR). Key secondary end points are PFS and DOR per modified RECIST v1.1 (BICR), OS, and safety; an exploratory biomarker analysis is planned. Clinical trial information: NCT03776136.

Prospective cardiac function monitoring in immunotherapy-treated patients

e14157

Background: Immune checkpoint inhibitors (ICI) demonstrate activity and long-term benefit in melanoma and other cancers. While certain immune-related toxicities have been well described, cardiac toxicities remain poorly characterized. We sought to characterize changes in cardiac function in advanced melanoma patients (pts) starting ICI treatment. Methods: A prospective, observational, single institution trial was performed to monitor cardiac function in pts receiving ICI. Eligible pts were adults with stage III/IV melanoma and ECOG 0-1, determined safe to exercise and without unstable cardiac symptoms. Pts received PD-1 monotherapy or combination ipilimumab/pembrolizumab. Rest and exercise stress cardiac testing (EKG, echocardiography) was conducted at baseline, at 3 months (mo), and at 6 mo. Patient-reported surveys were administered at baseline and at 6 mo. Results: Between Feb 2018 to Jan 2019, we prospectively identified 8 pts who completed baseline cardiac testing. As of Feb 2019, 6 pts completed 3-mo testing, and 4 completed 6-mo testing. Mean age was 57 years (range 34-68). 5 pts received pembrolizumab or nivolumab monotherapy, and 3 received ipilimumab/pembrolizumab. Resting LVOT-VTI decreased from 23.1±2.8 cm at baseline to 20.7±2.8cm at 6 mo (p = 0.047). Maximum HR at peak exercise decreased over time from 149.7±13 bpm at baseline to 114±20.5 bpm at 6 mo (p = 0.085) with concurrent decrease in maximum BP. Enrollment is ongoing. Conclusions: These data suggest measurable changes in left ventricular cardiac function at rest over time, in a prospective cohort of ICI-treated advanced melanoma pts. Further, we observe progressive loss of chronotropic and blood pressure response to exercise. These data have important implications for cancer survivorship in the era of immunotherapy. Updated data to be presented at the meeting include correlation with patient-reported symptoms. [Table: see text]