Advanced BRAF-mutant Melanoma Research Articles

Treatment resistance to melanoma therapeutics on a single cell level

Therapy targeting the BRAF-MEK cascade created a treatment revolution for patients with BRAF mutant advanced melanoma. Unfortunately, 80% patients treated will progress by 5 years follow-up. Thus, it is imperative we study mechanisms of melanoma progression and therapeutic resistance. We created a scRNA (single cell RNA) atlas of 128,230 cells from 18 tumors across the treatment spectrum, discovering melanoma cells clustered strongly by transcriptome profiles of patients of origins. Our cell-level investigation revealed gains of 1q and 7q as likely early clonal events in metastatic melanomas. By comparing patient tumors and their derivative cell lines, we observed that PD1 responsive tumor fraction disappears when cells are propagated in vitro. We further established three anti-BRAF-MEK treatment resistant cell lines using three BRAF mutant tumors. ALDOA and PGK1 were found to be highly expressed in treatment resistant cell populations and metformin was effective in targeting the resistant cells. Our study suggests that the investigation of patient tumors and their derivative lines is essential for understanding disease progression, treatment response and resistance.

Combined therapy of dabrafenib and an anti-HER2 antibody–drug conjugate for advanced BRAF-mutant melanoma

BackgroundMelanoma is the most lethal skin cancer characterized by its high metastatic potential. In the past decade, targeted and immunotherapy have brought revolutionary survival benefits to patients with advanced and metastatic melanoma, but these treatment responses are also heterogeneous and/or do not achieve durable responses. Therefore, novel therapeutic strategies for improving outcomes remain an unmet clinical need. The aim of this study was to evaluate the therapeutic potential and underlying molecular mechanisms of RC48, a novel HER2-target antibody drug conjugate, either alone or in combination with dabrafenib, a V600-mutant BRAF inhibitor, for the treatment of advanced BRAF-mutant cutaneous melanoma.MethodsWe evaluated the therapeutic efficacy of RC48, alone or in combination with dabrafenib, in BRAF-mutant cutaneous melanoma cell lines and cell-derived xenograft (CDX) models. We also conducted signaling pathways analysis and global mRNA sequencing to explore mechanisms underlying the synergistic effect of the combination therapy.ResultsOur results revealed the expression of membrane-localized HER2 in melanoma cells. RC48 effectively targeted and inhibited the growth of HER2-positive human melanoma cell lines and corresponding CDX models. When used RC48 and dabrafenib synergically induced tumor regression together in human BRAF-mutant melanoma cell lines and CDX models. Mechanically, our results demonstrated that the combination therapy induced apoptosis and cell cycle arrest while suppressing cell motility in vitro. Furthermore, global RNA sequencing analysis demonstrated that the combination treatment led to the downregulation of several key signaling pathways, including the PI3K-AKT pathway, MAPK pathway, AMPK pathway, and FOXO pathway.ConclusionThese findings establish a preclinical foundation for the combined use of an anti-HER2 drug conjugate and a BRAF inhibitor in the treatment of BRAF-mutant cutaneous melanoma.

Targeted therapy or immunotherapy in BRAF-mutated metastatic melanoma: a Spanish center's decade of experience.

Targeted therapies and immunotherapy are currently considered the mainstay first-line treatment for advanced BRAF-mutated melanoma. However, the impact of treatment (targeted therapy and immunotherapy) and the prognostic factors are still not clear. Medical records of 140 patients diagnosed with advanced melanoma between 2011 and 2021 were retrospectively reviewed to extract demographic, BRAF status, treatment, performance status, and survival data. ORR, PFS, and OS were compared between patients diagnosed with advanced melanoma and treated with first-line IT or BRAF/MEKi. The prognostic factors were assessed using Cox regression models. In all patients and those treated with immunotherapy, we did not find any effect of BRAF status on ORR, PFS, or OS. In patients with BRAF-mutated melanoma, ORR was 43.8% vs. 70% (P=0.04), PFS was 19.2 vs. 11.5 months (p=0.22), and OS was 33.4 vs. 16.4 months for the immunotherapy and targeted therapy groups, respectively (P=0.04). ECOG, presence of brain metastases, and high LDH level from initiation of first-line treatment were all associated with differences in PFS and OS. Patients with advanced BRAF-mutated melanoma treated with first-line immunotherapy had a significantly longer PFS and OS than those treated with first-line BRAF/MEKi; however, first-line BRAF/MEKi treatment had a significantly higher ORR than first-line immunotherapy.

Nivolumab treatment in a patient with BRAF mutant advanced melanoma and liver failure with encephalopathy.

We report the case of a patient with melanoma and liver failure with encephalopathy, successfully treated with nivolumab without major side effects and encouraging prolonged disease control. In June 2022, metastatic lesions appeared in the liver associated with melanoma progression under treatment. Liver biopsy was non-diagnostic. The patient developed fever, abdominal distension, and jaundice. Liver function tests (LFTs) began to deteriorate. Hepatic encephalopathy developed in accordance with the worsening liver functions in the patient. Upper abdominal MRI with primovist showed multiple, progressive, metastatic lesions in the liver and mild to moderate dilatation of the intrahepatic biliary tract. Patient was evaluated as acute cholangitis associated with the compression of the biliary tract by progressive liver metastases. In December 2022, the patient was started antibiotherapy for cholangitis and Nivolumab (240 mg flat dose, every 2 weeks) therapy. After the first dose, both LFT and constitutional symptoms began to improve. Subsequently, LFTs almost completely returned to normal, clinical response was achieved. Multiple metastatic lesions in the liver regressed in the radiological evaluation performed at the third month of nivolumab treatment. With partial response, nivolumab treatment is continued. In this case is reported patient with hepatic encephalopathy due to an advanced refractory melanome successfully, and safely, treated with programed cell death-1 (PD-1) inhibitors. Clinical trials to explore the benefits of these immunotherapies in the hepatic failure population with advanced solid tumors should be supported.

The Impact of Drug-Drug Interactions on the Toxicity Profile of Combined Treatment with BRAF and MEK Inhibitors in Patients with BRAF-Mutated Metastatic Melanoma.

BRAF and MEK inhibition is a successful strategy in managing BRAF-mutant melanoma, even if the treatment-related toxicity is substantial. We analyzed the role of drug-drug interactions (DDI) on the toxicity profile of anti-BRAF/anti-MEK therapy. In this multicenter, observational, and retrospective study, DDIs were assessed using Drug-PIN software (V 2/23). The association between the Drug-PIN continuous score or the Drug-PIN traffic light and the occurrence of treatment-related toxicities and oncological outcomes was evaluated. In total, 177 patients with advanced BRAF-mutated melanoma undergoing BRAF/MEK targeted therapy were included. All grade toxicity was registered in 79% of patients. Cardiovascular toxicities occurred in 31 patients (17.5%). Further, 94 (55.9%) patients had comorbidities requiring specific pharmacological treatments. The median Drug-PIN score significantly increased when the target combination was added to the patient's home therapy (p-value < 0.0001). Cardiovascular toxicity was significantly associated with the Drug-PIN score (p-value = 0.048). The Drug-PIN traffic light (p = 0.00821) and the Drug-PIN score (p = 0.0291) were seen to be significant predictors of cardiotoxicity. Patients with low-grade vs. high-grade interactions showed a better prognosis regarding overall survival (OS) (p = 0.0045) and progression-free survival (PFS) (p = 0.012). The survival analysis of the subgroup of patients with cardiological toxicity demonstrated that patients with low-grade vs. high-grade DDIs had better outcomes in terms of OS (p = 0.0012) and a trend toward significance in PFS (p = 0.068). DDIs emerged as a critical issue for the risk of treatment-related cardiovascular toxicity. Our findings support the utility of DDI assessment in melanoma patients treated with BRAF/MEK inhibitors.

COMBI-r: A Prospective, Non-Interventional Study of Dabrafenib Plus Trametinib in Unselected Patients with Unresectable or Metastatic BRAF V600-Mutant Melanoma.

Combined BRAF/MEK-inhibition constitutes a relevant treatment option for BRAF-mutated advanced melanoma. The prospective, non-interventional COMBI-r study assessed the effectiveness and tolerability of the BRAF-inhibitor dabrafenib combined with the MEK-inhibitor trametinib in patients with advanced melanoma under routine clinical conditions. Progression-free survival (PFS) was the primary objective, and secondary objectives included overall survival (OS), disease control rate, duration of therapy, and the frequency and severity of adverse events. This study enrolled 472 patients at 55 German sites. The median PFS was 8.3 months (95%CI 7.1-9.3) and the median OS was 18.3 months (14.9-21.3), both tending to be longer in pre-treated patients. In the 147 patients with CNS metastases, PFS was similar in those requiring corticosteroids (probably representing symptomatic patients, 5.6 months (3.9-7.2)) compared with those not requiring corticosteroids (5.9 months (4.8-6.9)); however, OS was shorter in patients with brain metastases who received corticosteroids (7.8 (6.3-11.6)) compared to those who did not (11.9 months (9.6-19.5)). The integrated subjective assessment of tumor growth dynamics proved helpful to predict outcome: investigators' upfront categorization correlated well with time-to-event outcomes. Taken together, COMBI-r mirrored PFS outcomes from other prospective, observational studies and confirmed efficacy and safety findings from the pivotal phase III COMBI-d/-v and COMBI-mb trials.

Inmunoterapia vs. terapia diana en el paciente con melanoma avanzado y mutación BRAF V600, ¿por cuál comenzar?

Systemic treatment with immunotherapy or targeted therapy can significantly improve survival in patients with advanced (metastatic or high-risk) melanoma. Fifty percent of patients with melanoma have a BRAF mutation. Decisions on optimal sequencing of systemic treatments should take into account drug- and tumor-related factors and patient characteristics. Although the combination of ipilimumab and nivolumab is associated with the best survival outcomes, it is associated with significant toxicity. Targeted therapy may be a more favorable option in certain clinical situations. We review the literature on immunotherapy and targeted therapy in melanoma and present an algorithm for guiding decision-making on their use as first-line systemic treatments for advanced BRAF-mutated melanoma.

A single-arm, phase II study of autophagy modulation using hydroxychloroquine in addition to encorafenib and cetuximab or panitumumab in metastatic BRAF-mutated colorectal cancer refractory to standard therapy.

TPS262 Background: BRAF mutations drive 5-10% of colon cancers. BRAF + EGFR inhibition with encorafenib + cetuximab is standard second-line therapy, per the BEACON trial, but responses are short-lived. Autophagy induction is implicated as a mechanism for this acquired resistance to therapy. Preclinical models have shown that BRAF inhibition leads to increased ATF4 phosphorylation and an overreliance on oxidative phosphorylation, both markers of autophagy induction. Use of hydroxychloroquine (HCQ), an antimalarial agent with anti-autophagy activity, reduces such markers and improves the cellular metabolic profile. This was confirmed clinically in the BAMM trial, a phase I/II study in which patients with advanced BRAF-mutated melanoma received dabrafenib, trametinib and HCQ (Mehnert JM et al, Clin Cancer Res 2022). This study asks a similar question in advanced, BRAF-mutated colon cancer, of whether autophagy inhibition overcomes acquired resistance to BRAF inhibition. Methods: This is a Phase II, single-arm, open-label study to be conducted at Robert H. Lurie Cancer Center of Northwestern University, Chicago, IL. The study was approved by the Northwestern University Institutional Review Board on 9/22/22 (IRB #: STU00217727); clinicaltrials.gov listing is pending. Key eligibility criteria: BRAF-mutated, stage IV colon cancer, with at least one line of therapy; ECOG PS 0/1, preserved organ function, and measurable disease at baseline. Key exclusion criteria: prior treatment with BRAF/MEK inhibitors; history of acute/chronic pancreatitis, psoriasis, or porphyria. Patients will receive standard of care encorafenib 300 mg daily and cetuximab IV weekly (panitumumab IV q 2 weeks can be used per investigator discretion). After a 14-day lead-in, HCQ 400 mg BID will be added. Each cycle is 28 days. CT scans will be done every 2 cycles, and blood will be taken every 2 weeks during the first 2 cycles for metabolomics analysis. The trial utilizes a Simon 2-stage admissible design. 14 patients will be enrolled in stage 1; if 4 or more responses are observed, the trial will continue to Stage 2 in which an additional 24 patients will be enrolled for a total sample size of 38 patients. The primary endpoint is objective response rate (ORR). Secondary endpoints are safety/efficacy, progression-free survival, overall survival and duration of response/stable disease. The exploratory endpoint is changes in markers of autophagy over time. The null hypothesis is an ORR of 20% (per the BEACON trial), and the alternative hypothesis is an ORR of 40%. This is the first trial exploring autophagy modulation in advanced, BRAF-mutated colon cancer. This study aims to show that autophagy inhibition with HCQ circumvents acquired resistance to BRAF + EGFR inhibition in advanced colon cancer.

Cost-effectiveness of immune checkpoint inhibition and targeted treatment in combination as adjuvant treatment of patient with BRAF-mutant advanced melanoma

BackgroundImmune checkpoint inhibitors (ICIs) and targeted treatments have improved the health outcomes of patients with advanced melanoma. However, due to the high cost of novel therapies, it is crucial to evaluate their value by considering both effectiveness and cost. To compare the cost-effectiveness of these novel agents (atezolizumab-vemurafenib-cobimetinib, vemurafenib-plus-cobimetinib, dabrafenib-plus-trametinib, and encorafenib-plus-binimetinib) for first-line treatment of metastatic melanoma with the BRAFV600 mutation.MethodsA patient-level model was developed to project the health outcomes of 4 strategies for patients with advanced melanoma. We estimated transition probabilities from the IMspire150 (ClinicalTrials.gov, NCT02908672), COMBI-AD (NCT01682083), and COLUMBUS (NCT01909453) trials using a parametric survival model. All health outcomes, including direct cost, quality-adjusted life-years (QALYs) and the incremental cost-effectiveness ratio (ICER), were estimated from the US payer perspective. Lifetime cost, QALYs, life-years (LYs), and ICERs were calculated. Univariable and probabilistic sensitivity analyses were performed to test model robustness, along with multiple scenario analyses.ResultsOf the 4 competing strategies, atezolizumab-vemurafenib-cobimetinib produced the best health outcomes, and the vemurafenib-cobimetinib strategy was the least expensive option. Atezolizumab-vemurafenib-cobimetinib, dabrafenib-plus-trametinib, and vemurafenib-cobimetinib formed the cost-effective frontier, indicating that the ordered ICERs were $325,113/QALYs for dabrafenib-plus-trametinib vs. vemurafenib-cobimetinib strategies and $2,247,500/QALYs for atezolizumab-vemurafenib-cobimetinib vs. dabrafenib-plus-trametinib strategies. Encorafenib-plus-binimetinib was dominated by the other 3 competing strategies. The drug price and first-line utility significantly influenced the model utcomes.ConclusionsFor BRAF-mutant advanced melanoma, the vemurafenib-cobimetinib strategy could be considered the most cost-effective treatment at the willingness-to-pay threshold of $150,000.

Cost-Effectiveness Analysis of Sequential Treatment Strategies for Advanced Melanoma in Real Life in France

Nine drugs have been marketed for 10 years for the treatment of advanced melanoma (AM). With half of patients reaching a second line, the optimal sequence of treatments remains unclear. To inform policy-makers about their efficiency, we performed a cost-effectiveness analysis of sequential strategies in clinical practice in France, for BRAF-mutated and wild-type patients. A multistate model was developed to describe treatment sequences, associated costs, and health outcomes over 10 years. Sequences, clinical outcomes, utility scores, and economic data were extracted from the prospective Melbase cohort, collecting individual data in 1518 patients since 2013, from their AM diagnosis until their death. To adjust the differences in patients' characteristics among sequences, weighting by inverse probability was used. In the BRAF-mutated population, the MONO-targeted therapies (TT)-anti-PD1 sequence was the less expensive, whereas the anti-PD1-BI-TT sequence had an incremental cost-effectiveness ratio (ICER) of 180,441 EUR/QALY. Regarding the BRAF wild-type population, the three sequences constituted the cost-effective frontier, with ICERs ranging from 116 to 806,000 EUR/QALY. For BRAF-mutated patients, the sequence anti-PD1-BI-TT appeared to be the most efficient one in BRAF-mutated AM patients until 2018. Regarding the BRAF wild-type population until 2018, the sequence starting with IPI+NIVO appeared inefficient compared to anti-PD1, considering the extra cost for the QALY gained.

First-line pembrolizumab versus dabrafenib/trametinib treatment for BRAF V600–mutant advanced melanoma

Limited data are available to assist the selection between immune checkpoint inhibitors and BRAF/mitogen-activated protein kinase kinase inhibitors as first-line treatment for patients with BRAF-mutant advanced malignant melanoma. To investigate the outcomes associated with first-line pembrolizumab or dabrafenib/trametinib treatment for advanced melanoma with activating BRAF V600 mutation. Data of patients with BRAF V600-mutant melanoma who were treated with first-line pembrolizumab (n=40) or dabrafenib/trametinib (n=32) were analyzed. Tumor response, progression-free survival, and overall survival were evaluated. Immune evasion accompanied with emerging resistance to BRAF/mitogen-activated protein kinase kinase inhibitors was assessed. A longer overall survival was observed after first-line pembrolizumab treatment than after first-line dabrafenib/trametinib treatment (hazard ratio=2.910, 95% CI: 1.552-5.459), although there were no significant differences in progression-free survival (P=.375) and response rate (P=.123). Emergence of resistance to dabrafenib/trametinib co-occurred with immune evasion, enabling melanoma cells to escape recognition and killing by Melan-A-specific CD8+ T cells. Analysis was conducted in a retrospective manner. Pembrolizumab may be recommended over BRAF/mitogen-activated protein kinase kinase inhibitors as the first-line treatment in patients with advanced BRAF V600-mutant melanoma.

Circulating miR-1246 and miR-485-3p as Promising Biomarkers of Clinical Response and Outcome in Melanoma Patients Treated with Targeted Therapy.

Simple SummarySeveral therapeutic options exist for patients with advanced BRAF-mutant melanoma. Biomarkers able to identify patients with refractory disease or with poor progression-free survival (PFS) and overall survival (OS) expectancy with respect to specific treatments might allow a more personalized therapeutic approach. Here, we profiled plasma miRNAs at baseline and at progression in patients treated with BRAF inhibitors (BRAFi) or BRAFi + MEKi. Selected miRNAs associated with response to therapy were subjected to validation by real-time quantitative RT-PCR. Receiver Operating Characteristics (ROC), Kaplan–Meier and univariate and multivariate Cox regression analyses were performed on miR-1246 and miR-485-3p baseline levels to assess their ability to discriminate between responding and non-responding patients and to determine their prognostic value for PFS and OS. Globally, our results suggest that circulating miR-1246 and miR-485-3p could be valuable biomarkers for identifying patients most likely to be resistant to targeted therapy or with a poor expectancy of PFS and OS. Prospective studies in a larger cohort of patients are warranted.Despite the significant improvements in advanced melanoma therapy, there is still a pressing need for biomarkers that can predict patient response and prognosis, and therefore support rational treatment decisions. Here, we investigated whether circulating miRNAs could be biomarkers of clinical outcomes in patients treated with targeted therapy. Using next-generation sequencing, we profiled plasma miRNAs at baseline and at progression in patients treated with BRAF inhibitors (BRAFi) or BRAFi + MEKi. Selected miRNAs associated with response to therapy were subjected to validation by real-time quantitative RT-PCR. Receiver Operating Characteristics (ROC), Kaplan–Meier and univariate and multivariate Cox regression analyses were performed on the validated miR-1246 and miR-485-3p baseline levels. The median baseline levels of miR-1246 and miR-485-3p were significantly higher and lower, respectively, in the group of patients not responding to therapy (NRs) as compared with the group of responding patients (Rs). In Rs, a trend toward an increase in miR-1246 and a decrease in miR-485-3p was observed at progression. Baseline miR-1246 level and the miR-1246/miR-485-3p ratio showed a good ability to discriminate between Rs and NRs. Poorer PFS and OS were observed in patients with unfavorable levels of at least one miRNA. In multivariate analysis, a low level of miR-485-3p and a high miR-1246/miR-485-3p ratio remained independent negative prognostic factors for PFS, while a high miR-1246/miR-485-3p ratio was associated with an increased risk of mortality, although statistical significance was not reached. Evaluation of miR-1246 and miR-485-3p baseline plasma levels might help clinicians to identify melanoma patients most likely to be unresponsive to targeted therapy or at higher risk for short-term PFS and mortality, thus improving their management.

Effectiveness of immunotherapy versus BRAF/MEK inhibitors in treatment-naïve BRAF-mutant advanced melanoma: A single institution retrospective analysis.

e21515 Background: Skin cancer is the most common type of cancer in the US. Melanoma constitutes about 1% of all skin cancers, but it accounts for most of skin cancer related deaths. In 2017, 85,000 new cases of melanoma were reported while 8000 people died. BRAF is the gene encoding for B-Raf protein; a serine/threonine-protein kinase involved in cell growth and survival. Activating mutations in BRAF are present in approximately 50% of melanomas. Therapeutics in melanoma have been rapidly evolving. Currently, advanced melanoma with a mutation in the BRAF gene has two different modalities for first-line treatment; immunotherapy which mediates checkpoint inhibition versus targeted therapy with BRAF + MEK inhibitors. The aim of our study was to compare effectiveness of immunotherapy versus BRAF/MEK inhibitors as first line treatment for metastatic BRAF-mutant advanced melanoma. Methods: A retrospective study of all patients aged ≥ 18 years, diagnosed with metastatic melanoma at our center between 1/1/2011 and 05/30/2021 was carried out. Patients who had BRAF negative melanoma or other active malignancies were excluded. Our primary endpoint was difference in overall survival and progression-free survival between two treatment groups. Secondary endpoint was to compare baseline characteristics associated with treatment options. Results: A total of 308 patients were diagnosed with advanced melanoma during the study period. N = 106 (34%) were found to have BRAF mutation. Of these, 88 (83%) received single-agent or combination immunotherapy while 18 (17%) received BRAF/MEK inhibitors. In immunotherapy group, 13 (14.7%) patients received combination immunotherapy while 75 (85%) got single agent treatment. 60 (56.6%) were males. Median age was 61 (89-21) years. Mean BMI at presentation was 29.5 ± 6.8 kg while mean LDH was 407 U/L. Mean age in immunotherapy and BRAF/MEK inhibitor group was 59.5 and 54.4 years, respectively. Differences between immunotherapy and BRAF/MEK inhibitors groups were observed in duration (months) between initiation of treatment and progression of disease (10.3 vs 7.23), death at time of last follow-up (21% vs 63%), remission at time of last follow up (37% vs 16%), and progression at time of last follow up (38% vs 16%). At the time of analysis, the mean follow-up was 28 ± 23.7 months in the immunotherapy group and 24 ± 23.3 months in the BRAF/MEK inhibitor group. Overall, at a mean follow up of 27.3 ± 23.5 months, no significant difference was found between the two treatment groups in unadjusted models in terms of overall survival (p 0.67) and progression free survival (p 0.16). Conclusions: Patients receiving first-line immunotherapy showed no significant survival benefit versus those receiving BRAF/MEK inhibitor therapy. This contrasts with other studies showing survival benefits in patients receiving immunotherapy as first line agent.

Real-world outcomes of Asian patients with advanced BRAF-mutant melanoma treated with first-line BRAF/MEK inhibitors, anti-PD-1 monotherapy, or combination of nivolumab plus ipilimumab: A multicenter retrospective study in Japan (B-CHECK-RWD study).

e21553 Background: The systemic treatment for advanced BRAF-mutant melanoma includes BRAF/MEK inhibitors (BRAF/MEKi), anti-PD-1 monotherapy (aPD1), and the combination of nivolumab plus ipilimumab (NIVO/IPI). Several studies have demonstrated favorable survival benefits for those treated with immunotherapy upfront. Most of these studies, however, were conducted among Caucasian-dominant cohorts; evidence for Asian patients is limited. Therefore, our objective was to assess the efficacy of first-line therapies for Asian patients in a real-world setting. Methods: We retrospectively collected the clinical data of Asian patients with advanced BRAF-mutant melanoma treated with first-line BRAF/MEKi, aPD1, or NIVO/IPI from 26 institutions in Japan. Clinical outcomes were determined by assessing the objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) by first-line therapies. Kaplan‐Meier curves and log‐rank tests, as well as multivariable Cox proportional hazard models were used to estimate survival probabilities. Results: We identified 316 Asian patients treated with first-line BRAF/MEKi (n = 224), aPD1 (n = 59), or NIVO/IPI (n = 33) between 2016 and 2021. At baseline, the median age of the patients in each treatment arm was 63, 62, and 54, respectively (p = 0.053). The ORR in the first-line therapy was 69%, 29%, and 27%, respectively (p &lt; 0.001). With a median follow-up of 18.9 months, the median PFS was 16.2, 5.6, and 6.4 months (p = 0.001); and the median OS was 36.9, 37.9 months, and not reached (p = 0.386), respectively. In a multivariable analysis, the predictive factors of short PFS were first-line therapy with aPD1 (HR, 2.44; 95%CI, 1.70-3.50, p &lt; 0.001) or NIVO/IPI (1.73; 1.06–2.83, p = 0.029), BRAF V600K (p = 0.031), ECOG PS ≥2 (p = 0.011), elevated lactate dehydrogenase (LDH) levels (p = 0.001), and M1a/M1c/M1d stages (p = 0.036/ &lt; 0.001/ &lt; 0.001, respectively). Predictive factors of short OS were BRAF V600K (p = 0.042), ECOG PS ≥2 (p = 0.001), elevated LDH levels (p &lt; 0.001), and M1c/M1d stages (both p &lt; 0.001). The OS did not differ significantly by first-line therapies between BRAF/MEKi, aPD1 (1.52; 0.98–2.34, p = 0.061), and NIVO/IPI (0.63; 0.31–1.27, p = 0.194). Conclusions: Although upfront NIVO/IPI showed the longest OS numerically, its superiority over BRAF/MEKi in Asian patients seems to be modest compared with Caucasian patients. Because upfront BRAF/MEKi showed an OS that was comparable with that of aPD1, BRAF/MEKi remains an active first-line therapy option, especially for those who are not amenable to take the high risk of immune-related toxicities.

The role of surgery (metastasectomy) in advanced BRAF positive melanoma during modern therapy.

e21512 Background: Improved overall survival in patients undergoing metаstasectomy for melanoma have been reported in several retrospective studies before era of modern therapy in melanoma. Rapid progress in BRAF and MEK targeted therapy (TT) and immunotherapy (IT) has led to significant improvements in objective response rates and survival rates in advanced melanoma patients. Unfortunately, part of patients have a resistance to modern therapy in one or more lesions. In 2019 Nelson DW et al published data when surgery followed by modern therapy in 47 matched pairs was associated with higher 5-year melanoma-specific survival (MSS) versus modern therapy alone (58.8% vs. 38.9%, p = 0.049). But data about modern therapy in BRAF + advanced melanoma with metastasectomy during therapy are limited. Methods: We conducted an observational retrospective chart review study and evaluated a subset of patients which underwent surgery (metastasectomy) with V600 BRAF-mutant advanced melanoma, who received therapy in a real-world setting in Russia. Survival analyses were performed using the Kaplan-Meier method, Log-rank, chi-square and Fisher exact tests were used for comparison between groups. Results: The observed population included 382 patients in Russia. The date of the first enrollment after all approvals was 8 October 2018, and the date of the last completed register was 27 April 2019. Among 382 patients, 107 (28%) patients received surgical treatment for advanced melanoma during modern therapy (removal of metastases from the brain, lungs, soft tissues and other organs). Surgery during first line therapy was performed in 60pts (56%), as second – in 25pts (23.4%) and third or higher line in 22pts (20.6%). Comparison of overall survival curves for all patients depending on the surgical treatment showed that the survival in the subgroup of patients with the presence of surgical treatment was higher than among patients who did not undergo metastasectomy: 24-months OS was 76.7 (95%CI, 65.6 – 84.6) and 53.7% (95%CI, 46.4-60.4), p = 0,0027). Conclusions: Our findings suggest that resection of distant metastases associated with improved overall survival despite all limitations in retrospective nature of the study. While modern systemic therapy have improved outcomes in advanced melanoma, metastasectomy remains associated with favorable survival. Surgery have to be a part of multidisciplinary care for patients with advanced melanoma.

Real-world treatment patterns and overall survivalin BRAF-mutant melanoma patients treated with immunotherapy or targeted therapy.

Aim: To assess overall survival (OS) in patients with advanced BRAF-mutant melanoma by first-line (1L) targeted therapy (TT) or checkpoint inhibitor (CPI) use, second-line (2L) TT or CPI use, and treatment sequence. Patients & methods: Advanced BRAF-mutant melanoma patients treated with 1L CPI or TT were selected from a real-world, electronic health record-derived database. Results: CPI was associated with improved survival after adjustment for potential confounders (hazard ratio, 0.75 [95% CI, 0.66-0.87]). Median OS was similar between 2L therapies and among likely treatment sequences. Conclusion: This real-world study demonstrated a survival benefit with 1L CPI versus TT. Analyses of 2L and treatment sequences were unable to detect or rule out clinically relevant differences in OS.

Real-World Evidence of Systemic Therapy Sequencing on Overall Survival for Patients with Metastatic BRAF-Mutated Cutaneous Melanoma.

Aim: To evaluate optimal systemic therapy sequencing (first-line targeted therapy (1L-TT) vs. first-line immunotherapy (1L-IO)) in patients with BRAF-mutated metastatic melanoma. Methods: Nation-wide prospective data of patients with newly diagnosed BRAF-mutated metastatic melanoma were retrieved from the Canadian Melanoma Research Network. Results: Our study included 79 and 107 patients in the 1L-IO and 1L-TT groups, respectively. There were more patients with ECOG 0–1 (91% vs. 72%, p = 0.023) in the 1L-IO group compared to the 1L-TT group. Multivariable Cox analysis suggested no OS differences between the two groups (HR 0.838, 95%CI 0.502–1.400, p = 0.500). However, patients who received 1L-TT then 2L-IO had the longest OS compared to 1L-IO without 2L therapy, 1L-IO then 2L-TT, and 1L-TT without 2L therapy (38.3 vs. 32.2 vs. 16.9 vs. 6.3 months, p < 0.001). For patients who received 2L therapy, those who received 2L-IO had a trend towards OS improvement compared with the 2L-TT group (21.7 vs. 8.9 months, p = 0.053). Conclusions: Our nation-wide prospective study failed to establish any optimal systemic therapy sequencing in advanced BRAF-mutant melanoma patients. Nevertheless, we provided evidence that immunotherapy has durable efficacy in advanced BRAF-mutant melanoma patients, regardless of treatment line, and that Canadian medical oncologists were selecting the appropriate treatment sequences in a real-world setting, based on patients’ clinical and tumour characteristics.

Oxidative Stress-Related Mechanisms in Melanoma and in the Acquired Resistance to Targeted Therapies.

Melanoma is a highly aggressive cancer with the poorest prognosis, representing the deadliest form of skin cancer. Activating mutations in BRAF are the most frequent genetic alterations, present in approximately 50% of all melanoma cases. The use of specific inhibitors towards mutant BRAF variants and MEK, a downstream signaling target of BRAF in the MAPK pathway, has significantly improved progression-free and overall survival in advanced melanoma patients carrying BRAF mutations. Nevertheless, despite these improvements, resistance still develops within the first year of therapy in around 50% of patients, which is a significant problem in managing BRAF-mutated advanced melanoma. Understanding these mechanisms is one of the mainstreams of the research on BRAFi/MEKi acquired resistance. Both genetic and epigenetic mechanisms have been described. Moreover, in recent years, oxidative stress has emerged as another major force involved in all the phases of melanoma development, from initiation to progression until the onsets of the metastatic phenotype and chemoresistance, and has thus become a target for therapy. In the present review, we discuss the current knowledge on oxidative stress and its signaling in melanoma, as well as the oxidative stress-related mechanisms in the acquired resistance to targeted therapies.

95P Long-term outcomes in patients with BRAF-mutant advanced melanoma: A real-world study

Approved first-line (1L) treatments for BRAF-mutant (BRAF-MT) advanced melanoma include nivolumab plus ipilimumab (NIVO + IPI), anti–PD-1 monotherapy, and BRAF plus MEK inhibitors (BRAFi + MEKi). Clinical trial data comparing these options are limited. A real-world study in patients (pts) with BRAF-MT melanoma showed 3-year overall survival (OS) of 58% and 27% with NIVO + IPI and BRAFi + MEKi, respectively (Pavlick AC, et al. EADO 2020). The longer-term follow-up is presented here.

Intermittent BRAF inhibition in advanced BRAF mutated melanoma results of a phase II randomized trial

Combination treatment with BRAF (BRAFi) plus MEK inhibitors (MEKi) has demonstrated survival benefit in patients with advanced melanoma harboring activating BRAF mutations. Previous preclinical studies suggested that an intermittent dosing of these drugs could delay the emergence of resistance. Contrary to expectations, the first published phase 2 randomized study comparing continuous versus intermittent schedule of dabrafenib (BRAFi) plus trametinib (MEKi) demonstrated a detrimental effect of the “on−off” schedule. Here we report confirmatory data from the Phase II randomized open-label clinical trial comparing the antitumoral activity of the standard schedule versus an intermittent combination of vemurafenib (BRAFi) plus cobimetinib (MEKi) in advanced BRAF mutant melanoma patients (NCT02583516). The trial did not meet its primary endpoint of progression free survival (PFS) improvement. Our results show that the antitumor activity of the experimental intermittent schedule of vemurafenib plus cobimetinib is not superior to the standard continuous schedule. Detection of BRAF mutation in cell free tumor DNA has prognostic value for survival and its dynamics has an excellent correlation with clinical response, but not with progression. NGS analysis demonstrated de novo mutations in resistant cases.