POLARIS: A phase 2 trial of encorafenib plus binimetinib evaluating high-dose and standard-dose regimens in patients with BRAF V600-mutant melanoma with brain metastasis.

Background: POLARIS (phase 2 [ph2]; NCT03911869) evaluated encorafenib (BRAF inhibitor) in combination with binimetinib (MEK1/2 inhibitor) in BRAF/MEK inhibitor-naïve patients with BRAF V600-mutant melanoma with asymptomatic brain metastases. Methods: The safety lead-in (SLI) assessed tolerability for high-dose encorafenib 300 mg twice daily (BID) plus binimetinib 45 mg BID. If the high dose was tolerable in ph2, patients would be randomized to receive high or standard dose (encorafenib 450 mg once daily [QD] plus binimetinib 45 mg BID). Otherwise, standard dose was evaluated as the recommended ph2 dose (RP2D). Patients who tolerated standard dosing during Cycle 1 could be dose escalated to encorafenib 600 mg QD plus binimetinib 45 mg BID in Cycle 2. Safety, efficacy, and pharmacokinetics were examined. Results: RP2D was standard encorafenib dosing, as >33% of evaluable SLI patients (3/9) had dose-limiting toxicities. Overall, of 13 safety-evaluable patients (10 SLI, 3 ph2), 9 had prior immunotherapy. There were 9 treatment-related adverse events in the SLI and 3 in ph2. Of the SLI efficacy-evaluable patients (n = 10), 1 achieved complete response and 5 achieved partial responses (PR); the brain metastasis response rate (BMRR) was 60% (95% CI: 26.2, 87.8). In ph2, 2 of 3 patients achieved PR (BMRR, 67% [95% CI: 9.4, 99.2]). Repeated encorafenib 300 mg BID dosing did not increase steady-state exposure compared with historical 450 mg QD data. Conclusions: Despite small patient numbers due to early trial termination, BMRR appeared similar between the SLI and ph2, and the ph2 safety profile appeared consistent with previous reports of standard-dose encorafenib in combination with binimetinib.

The side effect registry immuno-oncology (SERIO) - A tool for systematic analysis of immunotherapy-induced side effects.

BACKGROUND: Immunotherapies such as immune checkpoint inhibitors (ICI) are effective in multiple tumor entities but induce a plethora of side effects. Comprehensive real-world analyses are essential to identify new signals, characterize diagnostic features, enable risk assessment, determine pathomechanisms, assess effectiveness of side effect management and compare tumor outcomes. METHODS: The international online `Side-Effect Registry Immuno-Oncology´ (SERIO; www.serio-registry.org) collects rare, complex, and severe immunotherapy-induced side effects across all tumor entities with a strong focus on ICI-induced immune-related adverse events (irAE). The relational database management system (RDMS) contains structured data on patient and tumor characteristics, type of immunotherapy, treatment of side effects, and outcome of tumor and irAE. Data are captured within 25 organ modules including new modules for immune effector cell-associated neurotoxicity syndrome (ICANS) for CAR-T-cell therapies and cytokine release syndrome (CRS) for bispecific antibodies. Information on biological samples is gathered. RESULTS: A total of 1398 irAE cases have been documented by 58 centers from 13 countries in patients with 17 tumor types. IrAEs were induced by nine different immunotherapies including tebentafusp and CAR-T cell therapies, and resulted, among others, in neurological (7.6%), pulmonary (4.0%), and cardiac toxicities (2.9%). 50.0% of all irAEs were graded severe or life-threatening and 23.0% of patients received second-line therapy for steroid-refractory or steroid-dependent irAE. SERIO has contributed to 44 original publications on topics ranging from irMyocarditis to irEncephalitis to long-term persistent sequelae of immunotherapy. CONCLUSIONS: A reliable evidence base is crucial for decision-making in rare, complex or therapy-refractory irAE. SERIO can help optimize side effect management and thereby reduce morbidity and mortality induced by immunotherapy.

Validation of epidermal AMBRA1 and loricrin (AMBLor) as a prognostic biomarker for nonulcerated American Joint Committee on Cancer stage I/II cutaneous melanoma.

BACKGROUND: Combined expression of the autophagy-regulatory protein AMBRA1 (activating molecule in Beclin1-regulated autophagy) and the terminal differentiation marker loricrin in the peritumoral epidermis of stage I melanomas can identify tumour subsets at low risk of -metastasis. OBJECTIVES: To validate the combined expression of peritumoral AMBRA1 and loricrin (AMBLor) as a prognostic biomarker able to identify both stage I and II melanomas at low risk of tumour recurrence. METHODS: Automated immunohistochemistry was used to analyse peritumoral AMBRA1 and loricrin expression in geographically distinct discovery (n = 540) and validation (n = 300) cohorts of nonulcerated American Joint Committee on Cancer (AJCC) stage I and II melanomas. AMBLor status was correlated with clinical outcomes in the discovery and validation cohorts separately and combined. RESULTS: Analysis of AMBLor in the discovery cohort revealed a recurrence-free survival (RFS) rate of 95.5% in the AMBLor low-risk group vs. 81.7% in the AMBLor at-risk group (multivariate log-rank, P < 0.001) and a negative predictive value (NPV) of 96.0%. In the validation cohort, AMBLor analysis revealed a RFS rate of 97.6% in the AMBLor low-risk group vs. 78.3% in the at-risk group (multivariate log-rank, P < 0.001) and a NPV of 97.6%. In a multivariate model considering AMBLor, Breslow thickness, age and sex, analysis of the combined discovery and validation cohorts showed that the estimated effect of AMBLor was statistically significant, with a hazard ratio of 3.469 (95% confidence interval 1.403-8.580, P = 0.007) and an overall NPV of 96.5%. CONCLUSIONS: These data provide further evidence validating AMBLor as a prognostic biomarker to identify nonulcerated AJCC stage I and II melanoma tumours at low risk of disease recurrence.

A tailored approach to horizon scanning for cancer medicines.

BACKGROUND: Horizon scanning (HS) is the systematic identification of emerging therapies to inform policy and decision-makers. We developed an agile and tailored HS methodology that combined multi-criteria decision analysis weighting and Delphi rounds. As secondary objectives, we aimed to identify new medicines in melanoma, non-small cell lung cancer and colorectal cancer most likely to impact the Australian government's pharmaceutical budget by 2025 and to compare clinician and consumer priorities in cancer medicine reimbursement. METHOD: Three cancer-specific clinician panels (total n = 27) and a consumer panel (n = 7) were formed. Six prioritisation criteria were developed with consumer input. Criteria weightings were elicited using the Analytic Hierarchy Process (AHP). Candidate medicines were identified and filtered from a primary database and validated against secondary and tertiary sources. Clinician panels participated in a three-round Delphi survey to identify and score the top five medicines in each cancer type. RESULTS: The AHP and Delphi process was completed in eight weeks. Prioritisation criteria focused on toxicity, quality of life (QoL), cost savings, strength of evidence, survival, and unmet need. In both curative and non-curative settings, consumers prioritised toxicity and QoL over survival gains, whereas clinicians prioritised survival. HS results project the ongoing prevalence of high-cost medicines. Since completion in October 2021, the HS has identified 70 % of relevant medicines submitted for Pharmaceutical Benefit Advisory Committee assessment and 60% of the medicines that received a positive recommendation. CONCLUSION: Tested in the Australian context, our method appears to be an efficient and flexible approach to HS that can be tailored to address specific disease types by using elicited weights to prioritise according to incremental value from both a consumer and clinical perspective. POLICY SUMMARY: Since HS is of global interest, our example provides a reproducible blueprint for adaptation to other healthcare settings that integrates consumer input and priorities.

Prospective Comparison of T1-SPACE and MPRAGE for the Identification of Intrinsic T1 Hyperintensity in Patients with Intracranial Melanoma Metastases.

BACKGROUND AND PURPOSE: Volumetric TSE (3D-TSE) techniques are increasingly replacing volumetric magnetization-prepared gradient recalled-echo (3D-GRE) sequences due to improved metastasis detection. In addition to providing a baseline for assessing postcontrast enhancement, precontrast T1WI also identifies intrinsic T1 hyperintensity, for example, reflecting melanin or blood products. The ability of precontrast 3D-TSE to demonstrate intrinsic T1 hyperintensity is not clear from the literature; thus, this study compares precontrast 3D-TSE and 3D-GRE sequences for identifying intrinsic T1 hyperintensity in patients with metastatic melanoma. MATERIALS AND METHODS: Patients with metastatic melanoma and previously reported intrinsic T1 hyperintensity were identified. MRIs were performed at 3T including both 3D-GRE (MPRAGE) and 3D-TSE T1 sampling perfection with application-optimized contrasts by using different flip angle evolution (T1-SPACE) sequences precontrast. Axial 1-mm slices of both T1WI sequences were independently reviewed by 2 neuroradiologists, comparing the conspicuity of each lesion between the 2 sequences according to a 5-point scale and assessing whether the intrinsic T1 hyperintensity was attributable to melanin, blood products, or both. RESULTS: Twenty examinations were performed, with a total of 214 lesions demonstrating intrinsic T1 hyperintensity. Both readers found that intrinsic T1 hyperintensity was less conspicuous with T1-SPACE compared with MPRAGE for most lesions assessed (81.8%, averaged across both readers), including for lesions with intrinsic T1 hyperintensity attributable to melanin and blood products. Intrinsic T1 hyperintensity was rarely more conspicuous on T1-SPACE (1.4%). CONCLUSIONS: Precontrast intrinsic T1 hyperintensity is more conspicuous with MPRAGE than T1-SPACE. In patients with metastatic melanoma, 3D-GRE should be preferred as the precontrast T1WI sequence when both 3D-TSE and 3D-GRE are performed postcontrast and when not administering IV contrast.

Designing a wholly online, multidisciplinary Master of Cancer Sciences degree.

BACKGROUND: Improving oncology-specific knowledge and skills of healthcare professionals is critical for improving the outcomes of people with cancer. Many current postgraduate education offerings may be inaccessible to busy professionals, contain minimal consumer input or do not focus on the multidisciplinary nature of cancer care. In response to these needs, a Master of Cancer Sciences degree was developed. Our aim is to describe the development of the Master of Cancer Sciences. METHODS: We describe the development of the Master of Cancer Sciences, including its theoretical and its pedagogical underpinnings. RESULTS: Our approach to curriculum design was guided by Kern's Six-Step Approach to Medical Curriculum and underpinned by the Seven Principles of Online Learning. These approaches were further underpinned by the Cognitive Theory of Multimedia Learning which informed our approach to audio and visual information design. The pedagogy is interactive, experiential, interprofessional and importantly, includes consumers as educators. In practice, learning activities include peer feedback, multidisciplinary team meeting simulations, group work and clinical role plays. The online environment was visually shaped through infographics, high-quality educational videos and gamification. CONCLUSION: We have designed a Master of Cancer Sciences that is one of the first wholly online, cancer-specific Masters' programs. Its industry-led curriculum using evidence-based pedagogical choices utilises a range of novel digital formats and integrates the consumer perspective to provide a holistic overview of the field. Quantitative and qualitative evaluation of learning outcomes is ongoing.

Health-related quality of life in patients with melanoma brain metastases treated with immunotherapy.

Aims: To describe the health-related quality of life (HRQoL) of melanoma brain metastasis (MBM) patients throughout the first 18 weeks of ipilimumab-nivolumab or nivolumab treatment. Materials & methods: HRQoL data (European Organisation for Research and Treatment of Cancer's Core Quality of Life Questionnaire, additional Brain Neoplasm Module, and EuroQol 5-Dimension 5-Level Questionnaire) were collected as a secondary outcome of the Anti-PD1 Brain Collaboration phase II trial. Mixed linear modeling assessed changes over time, whereas the Kaplan-Meier method was used to determine median time to first deterioration. Results: Asymptomatic MBM patients treated with ipilimumab-nivolumab (n = 33) or nivolumab (n = 24) maintained baseline HRQoL. MBM patients with symptoms or leptomeningeal/progressive disease treated with nivolumab (n = 14) reported a statistically significant trend toward improvement. Conclusion: MBM patients treated with either ipilimumab-nivolumab or nivolumab did not report a significant deterioration in HRQoL within 18 weeks of treatment initiation. Clinical trial registration: NCT02374242 (ClinicalTrials.gov).

Historically, people whose melanoma had spread to the brain (known as brain metastases) lived only 4­6 months after diagnosis, with less than 15% alive at 12 months. However, the development of immunotherapies such as nivolumab and ipilimumab to treat advanced melanoma has resulted in more than 50% of patients being alive 5 years after diagnosis. With the effectiveness of these immunotherapies demonstrated in clinical trials, we wanted to examine the impact of these treatments on the health-related quality of life of people with melanoma brain metastases. Using data from a clinical trial evaluating the effectiveness of immunotherapies in people diagnosed with melanoma brain metastases, this study investigated the impact of nivolumab and nivolumab combined with ipilimumab on quality of life. We found that neither nivolumab alone nor nivolumab combined with ipilimumab had a negative effect on quality of life. In summary, this study provides further support for the use of these immunotherapies as first-line treatment for melanoma brain metastases.

Neoadjuvant Immunotherapy in Melanoma: The Paradigm Shift.

Clinical stage III melanoma, defined as resectable RECIST measurable nodal disease with or without in-transit metastases, represents approximately 15% of new melanoma diagnoses every year with additional cases presenting as recurrent nodal disease following previous treatment of a primary melanoma. The standard of care for patients with resectable clinical stage III melanoma is surgical resection, consisting of therapeutic lymph node dissection and/or resection of in-transit disease and consideration of adjuvant systemic therapy and occasionally adjuvant radiation. These patients have high rates of regional recurrence and progression to metastatic disease postsurgery, highlighting the need for better treatment options. With the success of immune checkpoint inhibitors in both the adjuvant and metastatic settings, the use of these agents in the neoadjuvant setting has been an emerging area of research interest. In this chapter, we will discuss the rationale for neoadjuvant immunotherapy; review impactful clinical trials; and define response monitoring, surgical considerations, emerging therapies, and unanswered questions for neoadjuvant therapy as a recent paradigm shift in the management of clinical stage III melanoma.

Efficacy and toxicity of adjuvant radiotherapy in recurrent melanoma after adjuvant immunotherapy.

BACKGROUND: In patients with stage III melanoma, despite surgical resection and adjuvant systemic therapy, locoregional recurrences still occur. The randomized, phase III Trans-Tasman Radiation Oncology Group (TROG) 02.01 trial demonstrated that adjuvant radiotherapy (RT) after complete lymphadenectomy (CLND) halves the incidence of melanoma recurrence within local nodal basins without improving overall survival or quality of life. However, the study was conducted prior to the current era of adjuvant systemic therapies and when CLND was the standard approach for microscopic nodal disease. As such, there is currently no data on the role of adjuvant RT in patients with melanoma who recur during or after adjuvant immunotherapy, including those that may or may not have undergone prior CLND. In this study, we aimed to answer this question. METHODS: Patients with resected stage III melanoma who received adjuvant anti-programmed cell death protein-1 (PD-1) (±ipilimumab) immunotherapy with a subsequent locoregional (lymph node and/or in-transit metastases) recurrence were retrospectively identified. Multivariable logistic and Cox regression analyses were conducted. Primary outcome was rate of subsequent locoregional recurrence; secondary outcomes were locoregional recurrence-free survival (lr-RFS2) and overall RFS (RFS2) to second recurrence. RESULTS: In total, 71 patients were identified: 42 (59%) men, 30 (42%) BRAF V600E mutant, 43 (61%) stage IIIC at diagnosis. Median time to first recurrence was 7 months (1-44), 24 (34%) received adjuvant RT and 47 (66%) did not. Thirty-three patients (46%) developed a second recurrence at a median of 5 months (1-22). The rate of locoregional relapse at second recurrence was lower in those who received adjuvant RT (8%, 2/24) compared with those who did not (36%, 17/47, p=0.01). Adjuvant RT at first recurrence was associated with an improved lr-RFS2 (HR 0.16, p=0.015), with a trend towards an improved RFS2 (HR 0.54, p=0.072) and no effect on risk of distant recurrence or overall survival. CONCLUSION: This is the first study to investigate the role of adjuvant RT in patients with melanoma with locoregional disease recurrence during or after adjuvant anti-PD-1-based immunotherapy. Adjuvant RT was associated with improved lr-RFS2, but not risk of distant recurrence, demonstrating a likely benefit in locoregional disease control in the modern era. Further prospective studies are required to validate these results.

The therapeutic potential of targeting minimal residual disease in melanoma.

BACKGROUND: Cutaneous melanoma is a lethal form of skin cancer with morbidity and mortality rates highest amongst European, North American and Australasian populations. The developments of targeted therapies (TTs) directed at the oncogene BRAF and its downstream mediator MEK, and immune checkpoint inhibitors (ICI), have revolutionized the treatment of metastatic melanoma, improving patient outcomes. However, both TT and ICI have their limitations. Although TTs are associated with high initial response rates, these are typically short-lived due to resistance. Conversely, although ICIs provide more durable responses, they have lower initial response rates. Due to these distinct yet complementary response profiles, it has been proposed that sequencing ICI with TT could lead to a high frequency of durable responses whilst circumventing the toxicity associated with combined ICI + TT treatment. However, several questions remain unanswered, including the mechanisms underpinning this synergy and the optimal sequencing strategy. The key to determining this is to uncover the biology of each phase of the therapeutic response. AIMS AND METHODS: In this review, we show that melanoma responds to TT and ICI in three phases: early response, minimal residual disease (MRD) and disease progression. We explore the effects of ICI and TT on melanoma cells and the tumour immune microenvironment, with a particular focus on MRD which is predicted to underpin the development of acquired resistance in the third phase of response. CONCLUSION: In doing so, we provide a new framework which may inform novel therapeutic approaches for melanoma, including optimal sequencing strategies and agents that target MRD, thereby ultimately improving clinical outcomes for patients.

A Phase Ib/II Trial of Combined BRAF and EGFR Inhibition in BRAF V600E Positive Metastatic Colorectal Cancer and Other Cancers: The EVICT (Erlotinib and Vemurafenib In Combination Trial) Study.

PURPOSE: BRAF V600E mutant metastatic colorectal cancer represents a significant clinical problem, with combination approaches being developed clinically with oral BRAF inhibitors combined with EGFR-targeting antibodies. While compelling preclinical data have highlighted the effectiveness of combination therapy with vemurafenib and small-molecule EGFR inhibitors, gefitinib or erlotinib, in colorectal cancer, this therapeutic strategy has not been investigated in clinical studies. PATIENTS AND METHODS: We conducted a phase Ib/II dose-escalation/expansion trial investigating the safety/efficacy of the BRAF inhibitor vemurafenib and EGFR inhibitor erlotinib. RESULTS: Thirty-two patients with BRAF V600E positive metastatic colorectal cancer (mCRC) and 7 patients with other cancers were enrolled. No dose-limiting toxicities were observed in escalation, with vemurafenib 960 mg twice daily with erlotinib 150 mg daily selected as the recommended phase II dose. Among 31 evaluable patients with mCRC and 7 with other cancers, overall response rates were 32% [10/31, 16% (5/31) confirmed] and 43% (3/7), respectively, with clinical benefit rates of 65% and 100%. Early ctDNA dynamics were predictive of treatment efficacy, and serial ctDNA monitoring revealed distinct patterns of convergent genomic evolution associated with acquired treatment resistance, with frequent emergence of MAPK pathway alterations, including polyclonal KRAS, NRAS, and MAP2K1 mutations, and MET amplification. CONCLUSIONS: The Erlotinib and Vemurafenib In Combination Trial study demonstrated a safe and novel combination of two oral inhibitors targeting BRAF and EGFR. The dynamic assessment of serial ctDNA was a useful measure of underlying genomic changes in response to this combination and in understanding potential mechanisms of resistance.

Overall survival with first-line atezolizumab in combination with vemurafenib and cobimetinib in BRAFV600 mutation-positive advanced melanoma (IMspire150): second interim analysis of a multicentre, randomised, phase 3 study.

BACKGROUND: Primary analysis of the phase 3 IMspire150 study showed improved investigator-assessed progression-free survival with first-line atezolizumab, vemurafenib, and cobimetinib (atezolizumab group) versus placebo, vemurafenib, and cobimetinib (control group) in patients with BRAFV600 mutation-positive melanoma. With a median follow-up of 18·9 months (IQR 10·4-23·8) at the primary analysis, overall survival data were immature. Here, we report the results from the second, prespecified, interim overall survival analysis. METHODS: The multicentre, double-blind, placebo-controlled, randomised, phase 3 IMspire150 study was done at 108 academic and community hospitals in 20 countries. Patients aged 18 years or older with previously untreated unresectable stage IIIc or stage IV melanoma and an Eastern Cooperative Oncology Group performance status of 0 or 1 were eligible for inclusion. Patients were randomly assigned (1:1) to receive either atezolizumab (840 mg intravenously on day 1 and 15) or placebo plus vemurafenib (960 mg or 720 mg twice daily orally) and cobimetinib (60 mg once daily orally; 21 days on and 7 days off) in 28-day cycles. Atezolizumab and placebo were added to treatment regimens from cycle two onwards. Randomisation was done centrally (Durham, NC, USA) based on a permuted block randomisation scheme (block size of 4) using an interactive web-based response system and was stratified by geographical region and baseline lactate dehydrogenase concentration. Overall survival was analysed in the intention-to-treat population and safety was analysed in all patients who received at least one dose of study drug according to actual treatment received. The primary endpoint was investigator-assessed progression-free survival, which was previously reported. Here, we report the second, prespecified, interim overall survival analysis, which was planned after about 270 overall survival events had occurred. The trial is ongoing, but is no longer enrolling patients, and it is registered with ClinicalTrials.gov, NCT02908672. FINDINGS: Between Jan 13, 2017, and April 26, 2018, 514 patients (median age 54 years [IQR 43-63]; 299 [58%] men and 215 [42%] women) were enrolled in the trial and randomly assigned to the atezolizumab group (256 [50%] patients) or the control group (258 [50%] patients). At the data cutoff (Sept 8, 2021), 273 patients had died (126 in the atezolizumab group and 147 in the control group). Median follow-up was 29·1 months (IQR 10·1-45·4) for the atezolizumab group versus 22·8 months (10·6-44·1) for the control group. Median overall survival was 39·0 months (95% CI 29·9-not estimable) in the atezolizumab group versus 25·8 months (22·0-34·6) in the control group (HR 0·84 [95% CI 0·66-1·06]; p=0·14). The most common adverse events of any grade in the atezolizumab group were blood creatine phosphokinase increased (123 [53%] of 231 patients), diarrhoea (116 [50%]), and pyrexia (115 [50%]). The most common adverse events of any grade in the control group were diarrhoea (157 [56%] of 280 patients), blood creatine phosphokinase increased (135 [48%]), and rash (119 [43%]). The most common grade 3-4 adverse events were increased lipase (54 [23%] of 231 patients in the atezolizumab group vs 62 [22%] of 280 patients in the control group), increased blood creatine phosphokinase (51 [22%] vs 50 [18%]), and increased alanine aminotransferase (32 [14%] vs 26 [9%]). Serious adverse events were reported in 112 (48%) patients in the atezolizumab group and 117 (42%) patients in the control group. Grade 5 adverse events were reported in eight (3%) patients in the atezolizumab group versus six (2%) patients in the control group. Two grade 5 adverse events (hepatitis fulminant and hepatic failure) in the atezolizumab group were considered to be associated with the triplet combination, and one event in the control group (pulmonary haemorrhage) was considered to be associated with cobimetinib. INTERPRETATION: Additional follow-up of the IMspire150 trial showed that overall survival was not significantly improved with atezolizumab, vemurafenib, and cobimetinib compared with placebo, vemurafenib, and cobimetinib in patients with BRAFV600 mutation-positive advanced melanoma. Results of the final analysis are awaited to establish whether a significant improvement in overall survival can be achieved with long-term treatment with this triplet combination versus vemurafenib plus cobimetinib. FUNDING: F Hoffmann-La Roche.

Prospective comparison of volumetric post-contrast T1-Sampling Perfection with Application optimized Contrasts by using different flip angle Evolutions and Magnetization-Prepared Rapid Acquisition with Gradient Echo in patients with metastatic melanoma.

INTRODUCTION: Volumetric turbo spin echo (3D-TSE) T1-weighted imaging techniques such as T1-SPACE (Sampling Perfection with Application optimized Contrasts by using different flip angle Evolutions) improve detection of intracranial metastases (IM) compared to volumetric magnetisation-prepared gradient recalled echo techniques such as MPRAGE (Magnetization-Prepared Rapid Acquisition with Gradient Echo). However, incomplete vascular suppression can produce false positives when using 3D-TSE. Research into 3D-TSE has generally targeted patients with known or suspected IM, but the clinical implications of false positives are greater in patients with lower likelihood of IM. This study examined additional findings identified by T1-SPACE in patients with metastatic melanoma, targeting patients with a lower incidence of IM. METHODS: Patients with metastatic melanoma and an upcoming brain MRI booking were identified prospectively. Consent for adding post-contrast T1-SPACE to the MRI protocol (which included MPRAGE) was obtained. Imaging was initially assessed without T1-SPACE. Subsequently, T1-SPACE images were examined and additional findings identified were recorded, including their correlation with MPRAGE. RESULTS: One hundred examinations were performed, 24 having evidence of active IM. T1-SPACE allowed identification of additional lesions in five patients, including two with small solitary IM not identified when first assessing MPRAGE. In 18 examinations, T1-SPACE identified additional equivocal findings, confidently attributed to artefact (most commonly normal vessels) following correlation with MPRAGE. CONCLUSION: T1-SPACE improves detection of small lesions in patients without known IM, changing patient management. False positives are common but can be clarified with MPRAGE. Combining T1-SPACE and MPRAGE allows both sensitivity and specificity to be optimised.

Correlation of MRI signal characteristics of intracranial melanoma metastases with BRAF mutation status.

BRAF V600 mutations (BRAF mut ) are associated with more pigmentation in primary melanomas, but data on melanin content of metastases are limited. This study compares signal characteristics of BRAF mut and BRAF-wildtype (BRAF wt ) intracranial melanoma metastases (IMM). MRI brain examinations at first diagnosis of IMM were identified, all performed at 3-Tesla including 1 mm volumetric pre- and postcontrast T1-weighted imaging and susceptibility-weighted imaging (SWI). Individual metastases were assessed by a neuroradiologist, stratified by size (≥10 mm, 'larger', vs. 2-9 mm, 'small'; up to 10 per group); presence of intrinsic T1-hyperintensity (T1H) and, if present, whether confidently attributable to melanin as opposed to haemorrhage; evidence of haemorrhage; presence of central necrosis. A total of 267 IMM in 73 patients were assessed (87 larger IMM, 180 small). The proportion of larger IMM was similar in both groups (31% BRAF mut and 36% BRAF wt ). In small IMM, MRI evidence of melanin was more common in BRAF mut patients (42% vs. 26%; P = 0.038). Haemorrhage was more common in larger IMM (51%, vs. 20% of small IMM; P < 0.0001), but did not differ based on BRAF status. Central necrosis was more common in larger IMM (44% vs. 7%; P < 0.0001) and in BRAF mut IMM (23% vs. 11%; P = 0.011). In the BRAF mut cohort, central necrosis was more common in patients without previous anti-BRAF therapy (33% vs. 7%; P = 0.0001). T1H attributable to melanin is only slightly more common in BRAF mut IMM than BRAF wt . Higher rates of central necrosis in BRAF mut patients without previous anti-BRAF therapy suggest that anti-BRAF therapy may affect the patterns of IMM growth.

Efficacy of anti-PD-1 and ipilimumab alone or in combination in acral melanoma.

BACKGROUND: Acral melanoma is a rare melanoma subtype with poor prognosis. Importantly, these patients were not identified as a specific subgroup in the landmark melanoma trials involving ipilimumab and the anti-programmed cell death protein-1 (PD-1) agents nivolumab and pembrolizumab. There is therefore an absence of prospective clinical trial evidence regarding the efficacy of checkpoint inhibitors (CPIs) in this population. Acral melanoma has lower tumor mutation burden (TMB) than other cutaneous sites, and primary site is associated with differences in TMB. However the impact of this on the effectiveness of immune CPIs is unknown. We examined the efficacy of CPIs in acral melanoma, including by primary site. METHODS: Patients with unresectable stage III/IV acral melanoma treated with CPI (anti-PD-1 and/or ipilimumab) were studied. Multivariable logistic and Cox regression analyses were conducted. Primary outcome was objective response rate (ORR); secondary outcomes were progression-free survival (PFS) and overall survival (OS). RESULTS: In total, 325 patients were included: 234 (72%) plantar, 69 (21%) subungual and 22 (7%) palmar primary sites. First CPI included: 184 (57%) anti-PD-1, 59 (18%) anti-PD-1/ipilimumab combination and 82 (25%) ipilimumab. ORR was significantly higher with initial anti-PD-1/ipilimumab compared with anti-PD-1 (43% vs 26%, HR 2.14, p=0.0004) and significantly lower with ipilimumab (15% vs 26%, HR 0.49, p=0.0016). Landmark PFS at 1 year was highest for anti-PD-1/ipilimumab at 34% (95% CI 24% to 49%), compared with 26% (95% CI 20% to 33%) with anti-PD-1 and 10% (95% CI 5% to 19%) with ipilimumab. Despite a trend for increased PFS, anti-PD-1/ipilimumab combination did not significantly improve PFS (HR 0.85, p=0.35) or OS over anti-PD-1 (HR 1.30, p=0.16), potentially due to subsequent therapies and high rates of acquired resistance. No outcome differences were found between primary sites. CONCLUSION: While the ORR to anti-PD-1/ipilimumab was significantly higher than anti-PD-1 and PFS numerically higher, in this retrospective cohort this benefit did not translate to improved OS. Future trials should specifically include patients with acral melanoma, to help determine the optimal management of this important melanoma subtype.

First-In-Human Phase I Study of the OX40 Agonist MOXR0916 in Patients with Advanced Solid Tumors.

PURPOSE: OX40, a receptor transiently expressed by T cells upon antigen recognition, is associated with costimulation of effector T cells and impairment of regulatory T-cell function. This first-in-human study evaluated MOXR0916, a humanized effector-competent agonist IgG1 monoclonal anti-OX40 antibody. PATIENTS AND METHODS: Eligible patients with locally advanced or metastatic refractory solid tumors were treated with MOXR0916 intravenously once every 3 weeks (Q3W). A 3+3 dose-escalation stage (0.2-1,200 mg; n = 34) was followed by expansion cohorts at 300 mg (n = 138) for patients with melanoma, renal cell carcinoma, non-small cell lung carcinoma, urothelial carcinoma, and triple-negative breast cancer. RESULTS: MOXR0916 was well tolerated with no dose-limiting toxicities observed. An MTD was not reached. Most patients (95%) experienced at least one adverse event (AE); 56% of AEs, mostly grade 1-2, were related to MOXR0916. Most common treatment-related AEs included fatigue (17%), diarrhea (8%), myalgia (7%), nausea (6%), decreased appetite (6%), and infusion-related reaction (5%). Pharmacokinetic (PK) parameters were dose proportional between 80 and 1,200 mg and supported Q3W administration. The recommended expansion dose based on PK and OX40 receptor saturation was 300 mg Q3W. Immune activation and upregulation of PD-L1 was observed in a subset of paired tumor biopsies. One renal cell carcinoma patient experienced a confirmed partial response. Overall, 33% of patients achieved stable disease. CONCLUSIONS: Although objective responses were rarely observed with MOXR0916 monotherapy, the favorable safety profile and evidence of tumor immune activation in a subset of patients support further investigation in combination with complementary agents such as PD-1/PD-L1 antagonists.

Tissue-resident memory T cells from a metastatic vaginal melanoma patient are tumor-responsive T cells and increase after anti-PD-1 treatment.

BACKGROUND: Vaginal melanoma (VM) is a rare cancer and has a poor response to immune checkpoint blockade (ICB). CD8+Tissue Resident Memory (TRM) T cells proliferate in response to ICB and correlate with longer survival in metastatic cutaneous melanoma. However, their capacity to respond to VM and their neoantigens is not known. METHODS: Using longitudinal samples, we explored the evolution of VM mutations by whole-exome sequencing and RNAseq, we also defined the immune context using multiplex immunohistochemistry and nanostring pan cancer immune profile. Then using fresh single cell suspensions of the metastatic samples, we explored VM T cells via mass cytometry and single cell RNAseq and T cell receptor sequencing (TCRseq). Finally, we investigated TRM, pre-TRM and exhausted T cell function against melanoma neo-antigens and melanoma differentiation antigens in vitro. RESULTS: Primary VM was non-inflamed and devoid of CD8+ TRM cells. In contrast, both metastases showed proliferating CD8+ TRM were clustered at the tumor margin, with increased numbers in the second ICB-refractory metastasis. The first metastasis showed dense infiltration of CD8+ T cells, the second showed immune exclusion with loss of melanoma cell Major histocompatibility complex (MHC)-I expression associated with downregulation of antigen presentation pathway gene expression. CD8+ TRM from both metastases responded to autologous melanoma cells more robustly than all other CD8+ T cell subsets. In addition, CD8+ TRM shared TCR clones across metastases, suggesting a response to common antigens, which was supported by recognition of the same neoantigen by expanded tumor infiltrating lymphocytes. CONCLUSIONS: In this study, we identified TRM clusters in VM metastases from a patient, but not primary disease. We showed TRM location at the tumor margin, and their superior functional response to autologous tumor cells, predicted neoantigens and melanoma differentiation antigens. These CD8+ TRM exhibited the highest tumor-responsive potential and shared their TCR with tumor-infiltrating effector memory T cells. This suggests VM metastases from this patient retain strong antitumor T cell functional responses; however, this response is suppressed in vivo. The loss of VG MHC-I expression is a common immune escape mechanism which was not addressed by anti-PD-1 monotherapy; rather an additional targeted approach to upregulate MHC-I expression is required.

Clinical validation and implementation of droplet digital PCR for the detection of BRAF mutations from cell-free DNA.

Droplet digital PCR (ddPCR) has been demonstrated in many research studies to be a sensitive method in the analysis of circulating tumour DNA (ctDNA) for identifying mutations and tracking disease. The transition of ddPCR into the diagnostic setting requires a number of critical steps including the assessment of accuracy and precision and ultimately implementation into clinical use. Here we present the clinical validation of ddPCR for the detection of BRAF mutations (V600E and V600K) from plasma. We describe the performance characteristics assessed including the limit of blank, limit of detection, ruggedness, accuracy, precision and the effect of the matrix. Overall, each assay could achieve a limit of detection of 0.5% variant allele fraction and was highly accurate, with 100% concordance of results obtained from routine diagnostic testing of formalin fixed tumour samples or reference controls (n=36 for BRAF V600E and n=30 for BRAF V600K). Inter-laboratory reproducibility across 12 plasma samples for each assay was also assessed and results were 100% concordant. Overall, we report the successful validation and translation of a ddPCR assay into clinical routine practice.