3301 Two year estimate of overall survival in COMBI-v, a randomized, open-label, phase III study comparing the combination of dabrafenib (D) and trametinib (T) with vemurafenib (Vem) as first-line therapy in patients (pts) with unresectable or metastatic BRAF V600E/K mutation-positive cutaneous melanoma

Novel Anti-Melanoma Compounds Are Efficacious in A375 Cell Line Xenograft Melanoma Model in Nude Mice

Despite the successes of immunotherapy, melanoma remains one of the deadliest cancers, therefore, the need for innovation remains high. We previously reported anti-melanoma compounds that work by downregulating spliceosomal proteins hnRNPH1 and H2. In a separate study, we reported that these compounds were non-toxic to Balb/C mice at 50 mg/kg suggesting their utility in in vivo studies. In the present study, we aimed to assess the efficacy of these compounds by testing them in A375 cell-line xenograft in nude athymic mice. Animals were randomized into four groups (n = 12/group): 10 mg/kg vemurafenib, and 25 mg/kg 2155-14 and 2155-18 thrice a week for 15 days along with a control group. The results revealed that both 2155-14 and 2155-18 significantly decreased the growth of A375 tumors, which was comparable to vemurafenib. These results were confirmed by tumor volume, weight, and histopathological examination. In conclusion, these results demonstrate the therapeutic potential of targeting spliceosomal proteins hnRNPH1 and H2.

Melanoma: A Historical Walk-through from Palliative Treatment to Modern-day Practice

"Melanoma is one of the most common types of malignancy in the world, and one known to carry a very poor prognosis until recent years. This review aims to outline the events in the history of the disease and the impact made by the discoveries along the way, as well as the modern-day consensus by referencing the updated literature regarding the present approach and future directions. In the last two decades, several studies and research have brought significant improvement in the diagnosis and clinical management of melanomas. The development of sentinel lymph node biopsy has brought major changes to the surgical approach to the disease, and modern therapies based on recently developed knowledge changed the death sentence this diagnosis once meant to a manageable condition despite its aggressiveness, keeping in mind that early diagnosis and safe margin excision remain the best and most optimistic course of treatment. "

Immune Checkpoint Inhibitors and RAS-ERK Pathway-Targeted Drugs as Combined Therapy for the Treatment of Melanoma

Metastatic melanoma is a highly immunogenic tumor with very poor survival rates due to immune system escape-mechanisms. Immune checkpoint inhibitors (ICIs) targeting the cytotoxic T-lymphocyte-associated protein 4 (CTLA4) and the programmed death-1 (PD1) receptors, are being used to impede immune evasion. This immunotherapy entails an increment in the overall survival rates. However, melanoma cells respond with evasive molecular mechanisms. ERK cascade inhibitors are also used in metastatic melanoma treatment, with the RAF activity blockade being the main therapeutic approach for such purpose, and in combination with MEK inhibitors improves many parameters of clinical efficacy. Despite their efficacy in inhibiting ERK signaling, the rewiring of the melanoma cell-signaling results in disease relapse, constituting the reinstatement of ERK activation, which is a common cause of some resistance mechanisms. Recent studies revealed that the combination of RAS-ERK pathway inhibitors and ICI therapy present promising advantages for metastatic melanoma treatment. Here, we present a recompilation of the combined therapies clinically evaluated in patients.

Okuläre Nebenwirkungen bei adjuvanten Melanomtherapien

Das Maligne Melanom hat in den letzten Jahren eine deutliche Erweiterung des Behandlungsspektrums erfahren. Neue adjuvante und palliative Therapiekonzepte mittels BRAF-/MEK- und Checkpoint-Inhibitoren erzielen zudem eine deutliche Verbesserung der Behandlungsergebnisse. Durch den vermehrten Medikamenteneinsatz mit neuen Wirkmechanismen kommt es gleichzeitig zur Häufung von bis dato eher seltenen und untypischen Nebenwirkungen. Wir berichten über zwei Patienten mit okulären Nebenwirkungen bei adjuvanter Therapie bei Malignem Melanom.

Eine biokuläre Glaskörperblutung nach adjuvanter Therapie mit BRAF-/MEK-Inhibitoren kann mittels mehrerer ophthalmologischer Operationen behandelt werden. Ein dadurch hocheingeschränkter Visus verbessert sich so auf einen regelrechten Visus.

Unser zweiter Patient hat durch eine adjuvante Therapie mit einem Checkpoint-Inhibitor eine medikamenteninduzierte komplette Abduzenzparese entwickelt. Diese ist unter einer Prednisolonstoßtherapie komplett reversibel.

Eine adäquate Risiko-Nutzen-Analyse für jeden Patienten ist besonders bei der adjuvanten Therapie notwendig.

Comparison Between First Line Target Therapy and Immunotherapy in Different Prognostic Categories of BRAF Mutant Metastatic Melanoma Patients: An Italian Melanoma Intergroup Study

Background

BRAF and MEK inhibitors target therapies (TT) and AntiPD1 immunotherapies (IT) are available first-line treatments for BRAF v600 mutant metastatic melanoma patients. ECOG PS (E), baseline LDH (L), and baseline number of metastatic sites (N) are well-known clinical prognostic markers that identify different prognostic categories of patients. Direct comparison between first-line TT and IT in different prognostic categories could help in first line treatment decision.

Methods

This is a retrospective analysis conducted in 14 Italian centers on about 454 metastatic melanoma patients, divided in 3 groups: group A—patients with E = 0, L within normal range, and N less than 3; group B—patients not included in group A or C; group C—patients with E > 0, L over the normal range, and N more than 3. For each prognostic group, we compared TT and IT in terms of progression free survival (PFS), overall survival (OS), and disease control rate (DCR).

Results

In group A, results in 140 TT and 36 IT-treated patients were, respectively, median PFS 35.5 vs 11.6 months (HR (95% CI) 1.949 (1.180–3.217) p value 0.009); median OS not reached vs 55 months (HR (95% CI) 1.195 (0.602–2.373) p value 0.610); DCR 99% vs 75% p value <0.001). In group B, results in 196 TT and 38 IT-treated patients were, respectively, median PFS 11.5 vs 5 months (HR 1.535 (1.036–2.275) p value 0.033); median OS 19 vs 20 months (HR 0.886 (0.546–1.437) p value 0.623); DCR 85% vs 47% p value <0.001). In group C, results in 41 TT and 3 IT-treated patients were, respectively, median PFS 6.4 vs 1.8 months (HR 4.860 (1.399–16) p value 0.013); median OS 9 vs 5 months (HR 3.443 (0.991–11.9) p value 0.052); DCR 66% vs 33% p value 0.612).

Conclusions

In good prognosis, group A—TT showed statistically significant better PFS than IT, also in a long-term period, suggesting that TT can be a good first line option for this patient category. It is only in group B that we observed a crossing of the survival curves after the 3rd year of observation in favor of IT. Few patients were enrolled in group C, so few conclusions can be made on it.

First line treatment of BRAF mutated advanced melanoma: Does one size fit all?

In the last decade, immunotherapy and target therapy have revolutionized the prognosis of patients with BRAF-V600 mutation-positive metastatic melanoma. To date, three different combinations of BRAF/MEK inhibitors have been approved for this population, showing comparable efficacy and unique toxicity profiles. Several immune-checkpoint inhibitors, including pembrolizumab, nivolumab and the combination of nivolumab plus ipilimumab, are also available options for untreated metastatic melanoma patients. A novel approach has emerged by combining immune-checkpoint inhibitors and targeted agents, based on preclinical hints of synergy, prompting clinical results from large randomized trials. Specifically, the triplet of atezolizumab, vemurafenib and cobimetinib has been recently approved by FDA for patients with untreated BRAF-mutant metastatic melanoma. With a wide variety of available treatment options in this setting, it is paramount to establish criteria to select the most effective and safe frontline tailored approaches, for each patient. Results from ongoing studies are awaited, to maximise the benefits in survival outcomes and quality of life for patients, balancing adverse events and clinical benefit. The purpose of this review is to summarize the current landscape of standard and experimental treatment strategies for the first line treatment of patients with BRAF-mutated advanced melanoma and discuss the best patient-centered tailored strategies in the first-line setting.

Cost-Effectiveness Analysis of Dabrafenib Plus Trametinib and Vemurafenib as First-Line Treatment in Patients with BRAF V600 Mutation-Positive Unresectable or Metastatic Melanoma in China

Objective: To evaluate the cost-effectiveness of dabrafenib plus trametinib combination therapy versus vemurafenib as first-line treatment in patients with BRAF V600 mutation-positive unresectable or metastatic melanoma from a healthcare system perspective in China. Methods: This study employed a partitioned survival model with three health states (progression-free survival, post-progression survival and dead) to parameterize the data derived from Combi-v trial and extrapolated to 30 years. Health states’ utilities were measured by EQ-5D-3L, also sourced from the Combi-v trial. Costs including drug acquisition costs, disease management costs and adverse event costs were based on the Chinese Drug Bidding Database and physician survey in China. The primary outcomes of the model were lifetime costs, life-years (LYs), quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratio (ICER). Deterministic and probabilistic sensitivity analyses were conducted, respectively. Result: Dabrafenib plus trametinib is projected to increase a patient’s life expectancy by 0.95 life-years over vemurafenib (3.03 vs. 2.08) and 1.09 QALY gains (2.48 vs. 1.39) with an incremental cost of $3833. The incremental cost-effectiveness ratio (ICER) was $3511 per QALY. In the probabilistic sensitivity analyses, at a threshold of $33,357 per QALY (three times the gross domestic product (GDP) per capita in China in 2020), the probability of dabrafenib plus trametinib being cost-effective was 90%. In the deterministic sensitivity analyses, the results were most sensitive to the dabrafenib plus trametinib drug costs, vemurafenib drug costs and discount rate of cost. Conclusion: Dabrafenib plus trametinib therapy yields more clinical benefits than vemurafenib. Using a threshold of $33,357 per QALY, dabrafenib plus trametinib is very cost-effective as compared with vemurafenib in China.

Decreased survival in patients treated by chemotherapy after targeted therapy compared to immunotherapy in metastatic melanoma

Background

Cytotoxic chemotherapy (CC) is currently used in metastatic melanoma after patients have developed resistance to immune checkpoint inhibitors (ICI) and/or Mitogen‐Activated Protein Kinase inhibitors (MAPKi). We sought to evaluate if a previous treatment by ICI or MAPKi influences clinical outcomes in patients treated by CC in metastatic melanoma.

Methods

Eighty‐eight patients with a metastatic melanoma, treated by CC after a previous treatment by ICI or MAPKi between January 2009 and October 2019, were retrospectively analyzed. Progression‐Free‐Survival (PFS), Overall Survival (OS), Overall Response Rate (ORR), and Disease Control Rate (DCR) were evaluated in patients treated by CC according to their prior treatment by ICI or MAPKi.

Results

Patients treated by CC after ICI tended to have a better median PFS (2.81 months (2.39–5.30) versus 2.40 months (0.91–2.75), p = 0.023), median OS (6.03 months (3.54–11.54) versus 4.44 months (1.54–8.59), p = 0.27), DCR (26.0% vs. 10.5%, p = 0.121) and ORR (22.0% vs. 7.9% p = 0.134) than those previously treated by MAPKi.

Conclusions

A prior treatment by an MAPKi may be associated with a worse response to CC than ICI, and further investigations should be performed to confirm if there is a clinical benefit to propose CC in this setting.

Adaptive Therapy for Metastatic Melanoma: Predictions from Patient Calibrated Mathematical Models

Adaptive therapy is an evolution-based treatment approach that aims to maintain tumor volume by employing minimum effective drug doses or timed drug holidays. For successful adaptive therapy outcomes, it is critical to find the optimal timing of treatment switch points in a patient-specific manner. Here we develop a combination of mathematical models that examine interactions between drug-sensitive and resistant cells to facilitate melanoma adaptive therapy dosing and switch time points. The first model assumes genetically fixed drug-sensitive and -resistant popul tions that compete for limited resources. The second model considers phenotypic switching between drug-sensitive and -resistant cells. We calibrated each model to fit melanoma patient biomarker changes over time and predicted patient-specific adaptive therapy schedules. Overall, the models predict that adaptive therapy would have delayed time to progression by 6-25 months compared to continuous therapy with dose rates of 6-74% relative to continuous therapy. We identified predictive factors driving the clinical time gained by adaptive therapy, such as the number of initial sensitive cells, competitive effect, switching rate from resistant to sensitive cells, and sensitive cell growth rate. This study highlights that there is a range of potential patient-specific benefits of adaptive therapy and identifies parameters that modulate this benefit.

First-line immunotherapy versus targeted therapy in patients with BRAF-mutant advanced melanoma: a real-world analysis

Aim: To compare effectiveness of nivolumab + ipilimumab (NIVO + IPI) versus BRAF + MEK inhibitors (BRAFi + MEKi) in patients with BRAF-mutant advanced melanoma in the real-world setting. Materials & methods: This study used the Flatiron Health electronic medical record database. Results: After adjusting for differences in baseline characteristics, NIVO + IPI was associated with a 32% reduction in risk of death versus BRAFi + MEKi. At a mean follow-up of 15-16 months, 64% of NIVO + IPI patients and 43% of BRAFi + MEKi patients were alive; subsequent therapy was administered to 33 and 41% of patients, respectively. After first-line NIVO + IPI, 20% of patients died before subsequent therapy, whereas 32% died after first-line BRAFi + MEKi. Conclusion: In this real-world study, patients treated with first-line NIVO + IPI showed significant survival benefit versus those receiving first-line BRAFi + MEKi.

The MAP kinase signal transduction pathway: promising therapeutic targets used in the treatment of melanoma

INTRODUCTION

Mitogen-activated protein kinase (MAPK) signal transduction pathway inhibition through the use of agents binding to signal cascade kinases BRAF and MEK has become a key treatment strategy of patients with BRAF-mutant, unresectable melanoma.

AREAS COVERED

Detailed analysis is undertaken of the current data, presenting the efficacy and safety of recently developed therapies targeting BRAF and MEK inhibition in the setting of unresectable melanoma. MAPK signal transduction, translational findings, current phase I, II and III clinical trials, and ongoing studies are explored, including use of MAPK pathway inhibition in the neoadjuvant and adjuvant settings as well as in combination with immunotherapy and other therapies.

EXPERT OPINION

Inhibition of the MAPK pathway significantly improves response, progression-free survival, disease specific survival, and overall survival for patients with BRAF-mutant, unresectable melanoma. The concurrent administration of BRAF and MEK inhibiting agents improves response rate and outcomes and reduces serious adverse effects, including development of new cutaneous malignancies. Triplet therapy with BRAK/MEK combination and immunotherapy has shown in early results to increase duration of response and may be best used sequentially as opposed to concurrently to avoid treatment limiting toxicities. Current clinical trials will further define these therapies and their impact on treatment of melanoma.

Incorporating traditional and emerging biomarkers in the clinical management of metastatic colorectal cancer: an update

INTRODUCTION

Molecular profiling has led to significantly longer survival in metastatic colorectal cancer (mCRC) patients. Clinical guidelines recommend testing for KRAS/NRAS, BRAF and MSI status, and new biomarkers such as HER2 amplification and NTRK fusions have emerged more recently in refractory CRC, supported by overwhelming clinical relevance. These biomarkers can guide treatment management to improve clinical outcomes in these patients.

AREAS COVERED

Preclinical and clinical data over the last decade were reviewed for known and novel biomarkers with clinical implications in refractory CRC. Molecular alterations are described for classic and novel biomarkers, and data for completed and ongoing studies with targeted and immunotherapies are presented.

EXPERT OPINION

Use of targeted therapies based on biomarker testing in CRC has enabled impressive improvements in clinical outcomes in refractory patients. BRAF, MSI, NRAS and KRAS should be tested upfront in all patients given their indisputable therapeutic implications. Other molecular alterations such as HER2 and NTRK are emerging. Testing for these alterations may further improve outcomes for refractory CRC patients. Nonetheless, many key aspects remain to be defined including the optimal timing and technique for testing, the most adequate panel, and whether all patients should be tested for all alterations.

BRAF mutation and its inhibitors in sarcoma treatment

The mitogen‐activated protein kinase (MAPK) signaling pathway plays a significant role in mediating cellular physiological activities, such as proliferation, differentiation, apoptosis, and senescence. This signaling pathway is composed of several major proto‐oncogenes of RAS/RAF/MEK/ERK, among which the BRAF proto‐oncogene, as one of the three members of the RAF family, has a higher mutation rate than ARAF and CRAF and has attracted extensive attention. Regarding the BRAF mutation, approximately 95% of BRAF mutations belong to the BRAF V600E mutation, which can enhance the expression of the MAPK signaling pathway and is thus related to the occurrence and development of various malignant tumors and has been successfully identified as a therapeutic target. Moreover, drug resistance to BRAF inhibitor treatment also appears to be an important issue. Considering the successful use of BRAF inhibitors in melanoma, we provide a brief overview of the BRAF mutations, including their basic structures and activation mechanisms, and the new classification method for BRAF mutations. Most importantly, we summarize the results of BRAF inhibitor treatment in different sarcomas. To overcome drug resistance to BRAF inhibitor treatment, we also outline the different mechanisms of drug resistance to BRAF inhibitor treatment and introduce the combination strategy of BRAF inhibitors with other targeted therapies.

Real-world efficacy and safety data for dabrafenib and trametinib combination therapy in Japanese patients with BRAF V600 mutation-positive advanced melanoma

We conducted a retrospective investigation of the efficacy and safety of dabrafenib and trametinib combination therapy in Japanese patients with BRAF V600 mutation-positive advanced melanoma in real-world clinical practise. The study analyzed 50 patients who received dabrafenib and trametinib combination therapy for BRAF V600 mutation-positive advanced melanoma in our hospital (26 men and 24 women, aged 21-86 years, inclusive; median age, 53 years). The response rate was 72.3%, with complete response (CR) achieved in eight cases (17.0%), partial response in 26 (55.3%), stable disease in nine (19.1%) and progressive disease in four (8.5%). Median progression-free survival (PFS) was 12 months, and median overall survival (OS) was 23 months. Disease progression occurred in 29 of the 50 patients during the study period, and 25 patients died. Baseline lactate dehydrogenase and the number of organs with metastasis were important predictive factors for PFS and OS, and CR to combination therapy was a predictive factor for long-term remission. Adverse events occurred in 88% of cases; 16% were grade 3 or worse. The adverse events observed in 50% of more of patients were rash (56%) and pyrexia (52%). The efficacy of dabrafenib and trametinib combination therapy in Japanese patients was similar to that reported in global studies, and the same adverse events were generally reported; however, rash tended to occur more frequently in the patients in our study.

Efficacy, Safety, and Tolerability of Approved Combination BRAF and MEK Inhibitor Regimens for BRAF-Mutant Melanoma

No head-to-head studies exist comparing BRAF inhibitor/MEK inhibitor (BRAFi/MEKi) combination treatments for BRAF-mutant melanoma. A side-by-side analysis of randomized phase III trials is presented that evaluated dabrafenib/trametinib, vemurafenib/cobimetinib, and encorafenib/binimetinib. The baseline characteristics, efficacy, and safety were compared: COMBI-v (dabrafenib/trametinib versus vemurafenib); coBRIM (vemurafenib/cobimetinib versus vemurafenib); and COLUMBUS (encorafenib/binimetinib versus encorafenib and vemurafenib). Vemurafenib was the control arm in all studies. The data sources included literature databases, European public assessment reports, U.S. Food and Drug Administration review documents, and prescribing information. The baseline characteristics were similar, except for coBRIM, which had a higher proportion of patients with elevated lactate dehydrogenase (LDH) levels. The median progression-free survival (PFS) and overall response rate (ORR) were similar across the trials, although numerically higher values were observed with encorafenib/binimetinib. In contrast, the median overall survival (OS) was numerically longer with encorafenib/binimetinib (33.6 months) compared to dabrafenib/trametinib (25.6 months) and vemurafenib/cobimetinib (22.3 months). Among vemurafenib arms, PFS, ORR, and OS were similar, despite variations in the baseline LDH. Each combination displayed a unique safety profile, with higher incidences of pyrexia with dabrafenib/trametinib and photosensitivity reactions with vemurafenib/cobimetinib. This analysis of BRAFi/MEKi combinations for BRAF-mutant melanoma, while limited as not a direct head-to-head clinical trial, highlights the differences in tolerability and efficacy that may be useful for therapeutic decision making.

Binimetinib, Encorafenib, and Cetuximab Triplet Therapy for Patients With BRAF V600E-Mutant Metastatic Colorectal Cancer: Safety Lead-In Results From the Phase III BEACON Colorectal Cancer Study

PURPOSE

To determine the safety and preliminary efficacy of selective combination targeted therapy for BRAF V600E-mutant metastatic colorectal cancer (mCRC) in the safety lead-in phase of the open-label, randomized, three-arm, phase III BEACON Colorectal Cancer trial ( ClinicalTrials.gov identifier: NCT02928224; European Union Clinical Trials Register identifier: EudraCT2015-005805-35).

PATIENTS AND METHODS

Before initiation of the randomized portion of the BEACON Colorectal Cancer trial, 30 patients with BRAF V600E-mutant mCRC who had experienced treatment failure with one or two prior regimens were to be recruited to a safety lead-in of encorafenib 300 mg daily, binimetinib 45 mg twice daily, plus standard weekly cetuximab. The primary end point was safety, including the incidence of dose-limiting toxicities. Efficacy end points included overall response rate, progression-free survival, and overall survival.

RESULTS

Among the 30 treated patients, dose-limiting toxicities occurred in five patients and included serous retinopathy (n = 2), reversible decreased left ventricular ejection fraction (n = 1), and cetuximab-related infusion reactions (n = 2). The most common grade 3 or 4 adverse events were fatigue (13%), anemia (10%), increased creatine phosphokinase (10%), increased AST (10%), and urinary tract infections (10%). In 29 patients with BRAF V600E-mutant tumors (one patient had a non-BRAF V600E-mutant tumor and was not included in the efficacy analysis), the confirmed overall response rate was 48% (95% CI, 29.4% to 67.5%), median progression-free survival was 8.0 months (95% CI, 5.6 to 9.3 months), and median overall survival was 15.3 months (95% CI, 9.6 months to not reached), with median duration of follow-up of 18.2 months (range, 16.6 to 19.8 months).

CONCLUSION

In the safety lead-in, the safety and tolerability of the encorafenib, binimetinib, and cetuximab regimen is manageable and acceptable for initiation of the randomized portion of the study. The observed efficacy is promising compared with available therapies and, if confirmed in the randomized portion of the trial, could establish this regimen as a new standard of care for previously treated BRAF V600E-mutant mCRC.

Dabrafenib, trametinib and pembrolizumab or placebo in BRAF-mutant melanoma

Blocking programmed death 1 (PD-1) may enhance the durability of anti-tumor responses that are induced by the combined inhibition of BRAF and MEK¹. Here we performed a randomized phase 2 trial ( NCT02130466 ), in which patients with treatment-naive BRAF^V600E/K-mutant, advanced melanoma received the BRAF inhibitor dabrafenib and the MEK inhibitor trametinib together with the PD-1-blocking antibody pembrolizumab (triplet; n = 60) or placebo (doublet; n = 60). The primary end point of progression-free survival was numerically improved in the triplet group-16.0 months-compared with 10.3 months in the doublet group (hazard ratio, 0.66; P = 0.043); however, the trial did not reach the planned benefit for a statistically significant improvement. Median duration of response was 18.7 months (95% confidence interval, 10.1-22.1) and 12.5 months (95% confidence interval, 6.0-14.1); 59.8 and 27.8% of responses were estimated to have lasted for more than 18 months for triplet and doublet treatment, respectively. Grade 3-5 treatment-related adverse events occurred in 58.3 and 26.7% of patients treated with triplet and doublet therapies, respectively, which were most commonly fever, increased transaminase levels and rash. One patient who received triplet therapy died of pneumonitis. In summary, triplet therapy with dabrafenib, trametinib and pembrolizumab conferred numerically longer progression-free survival and duration of response with a higher rate of grade 3/4 adverse events compared with the doublet therapy of dabrafenib, trametinib and placebo.

Using a Benefit-Risk Analysis Approach to Capture Regulatory Decision Making: Melanoma

Drug regulators seek to make decisions regarding drug approvals based on analysis of the relevant benefits and risks. In this work, 25 US Food and Drug Administration (FDA) decisions on melanoma drugs were identified and analyzed based on clinical trial results published between 1999 and 2017. In each case, the benefits and risks of the new drug in each clinical trial relative to a comparator (typically the control arm of the same clinical trial) were quantified. The benefits and risks were analyzed using a common scale to allow for direct comparison. A sensitivity analysis was conducted using vemurafenib to explore the magnitude of uncertainty in the quantitative assessments. The associated FDA decision outcomes of the new drugs were consistent with the benefits and risks quantified in this work.

Five-year outcomes from a phase 3 METRIC study in patients with BRAF V600 E/K-mutant advanced or metastatic melanoma

BACKGROUND

Primary findings from the METRIC (TMT212A2301) study demonstrated that trametinib improved progression-free survival (PFS) and overall survival (OS) compared with chemotherapy in patients with unresectable or metastatic cutaneous melanoma with a BRAF V600 E/K mutation. However, clinical data characterising the long-term use of these therapies in combination with BRAF inhibitors or as monotherapies are limited.

METHODS

In this open-label, phase 3 study, 322 patients with BRAF V600 E/K-mutant metastatic melanoma were randomised in a 2:1 ratio to receive trametinib (2 mg orally, once daily; n = 214) or chemotherapy (dacarbazine [1000 mg/m2] or paclitaxel [175 mg/m2] intravenously, every 3 weeks; n = 108). Patients who progressed on chemotherapy were allowed to cross over and receive trametinib. Five-year results of efficacy and safety analyses are reported.

RESULTS

The median PFS was 4.9 months in the trametinib arm versus 1.5 months in the chemotherapy arm (hazard ratio, 0.54; 95% confidence interval, 0.41-0.73). Landmark OS rates for trametinib versus chemotherapy arms at 1 year, 2 years and 5 years were 60.9% versus 49.6%, 32.0% versus 29.4% and 13.3% versus 17.0%, respectively. Most patients (n = 70 [65%]) from the chemotherapy arm crossed over to the trametinib arm early in their treatment. No unexpected adverse events were reported.

CONCLUSIONS

This 5-year follow-up of patients with BRAF V600 E/K-mutant metastatic melanoma on a targeted therapy demonstrates that long-term use of trametinib is possible with no new or unexpected adverse events. Some patients experienced long-term survival benefit with trametinib monotherapy (METRIC ClinicalTrials.gov number, NCT01245062.).

Patient preferences for treatment of metastatic melanoma

AIM

To investigate patient preferences for clinical attributes of first-line metastatic melanoma treatments.

MATERIALS & METHODS

A discrete-choice experiment and best-worst scaling exercise were used to assess relative preferences for treatment attributes.

RESULTS

The 200 survey respondents had distinct preferences. Avoiding a 30% risk of colitis or hormone gland problems and avoiding severe fever were more important to respondents than avoiding a 20% risk of extreme sun sensitivity (p < 0.05). Patients preferred taking pills to receiving intravenous infusions in a clinic. When attributes were combined, approximately 85% of respondents preferred a risk profile similar to targeted therapy over a profile similar to immunotherapy, holding efficacy constant.

CONCLUSION

Taking patient preferences into account can help patients get the full benefit from metastatic melanoma therapies.

Advanced stage melanoma therapies: Detailing the present and exploring the future

Metastatic melanoma therapies have proliferated over the last ten years. Prior to this, decades passed with only very few drugs available to offer our patients, and even then, those few drugs had minimal survival benefits. Many treatment options emerged over the last ten years with diverse mechanisms of action. Further, combination regimens have demonstrated superiority over monotherapy, especially for targeted agents. Each therapeutic combination possesses different advantages and side effect profiles. In this review, we outline the United States Food and Drug Administration-approved melanoma treatment agents and therapies currently in clinical development, focusing on combination approaches.

Overall survival in patients with BRAF-mutant melanoma receiving encorafenib plus binimetinib versus vemurafenib or encorafenib (COLUMBUS): a multicentre, open-label, randomised, phase 3 trial

BACKGROUND

Encorafenib plus binimetinib and encorafenib alone improved progression-free survival compared with vemurafenib in patients with BRAF^V600-mutant melanoma in the COLUMBUS trial. Here, we report the results of the secondary endpoint of overall survival.

METHODS

COLUMBUS was a two-part, randomised, open-label, phase 3 study done at 162 hospitals in 28 countries. Eligible patients were aged at least 18 years with histologically confirmed, locally advanced, unresectable, or metastatic cutaneous melanoma, or unknown primary melanoma, BRAF^V600E or BRAF^V600K mutation, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and were treatment naive or had progressed on or after first-line immunotherapy. In part 1 of the study, patients were randomly assigned (1:1:1) by use of interactive response technology to receive oral encorafenib 450 mg once daily plus oral binimetinib 45 mg twice daily (encorafenib plus binimetinib group), oral encorafenib 300 mg once daily (encorafenib group), or oral vemurafenib 960 mg twice daily (vemurafenib group). Randomisation was stratified by the American Joint Committee on Cancer stage, ECOG performance status, and BRAF mutation status. The primary outcome of the trial, progression-free survival with encorafenib plus binimetinib versus vemurafenib, was reported previously. Here we present the prespecified interim overall survival analysis. Efficacy analyses were by intent to treat. Safety was analysed in patients who received at least one dose of study drug. Part 2 of the study was initiated at the request of the US Food and Drug Administration to better understand the contribution of binimetinib to the combination therapy by comparing encorafenib 300 mg once daily plus binimetinib 45 mg twice daily with encorafenib 300 mg once daily alone. Results of part 2 will be published separately. This trial is ongoing and is registered with ClinicalTrials.gov, number NCT01909453, and EudraCT, number 2013-001176-38.

FINDINGS

Between Dec 30, 2013, and April 10, 2015, 577 of 1345 screened patients were randomly assigned to receive encorafenib plus binimetinib (n=192), encorafenib (n=194), or vemurafenib (n=191). Median follow-up for overall survival was 36·8 months (95% CI 35·9-37·5). Median overall survival was 33·6 months (95% CI 24·4-39·2) with encorafenib plus binimetinib and 16·9 months (14·0-24·5) with vemurafenib (hazard ratio 0·61 [95% CI 0·47-0·79]; two-sided p<0·0001). The most common grade 3 or 4 adverse events did not change substantially from the first report; those seen in more than 5% of patients treated with encorafenib plus binimetinib were increased γ-glutamyltransferase (18 [9%] of 192 patients), increased blood creatine phosphokinase (14 [7%]), and hypertension (12 [6%]); those seen with encorafenib alone were palmar-plantar erythrodysaesthesia syndrome (26 [14%] of 192 patients), myalgia (19 [10%]), and arthralgia (18 [9%]); and with vemurafenib the most common grade 3 or 4 adverse event was arthralgia (11 [6%] of 186 patients). One death in the combination treatment group was considered by the investigator to be possibly related to treatment.

INTERPRETATION

The combination of encorafenib plus binimetinib provided clinically meaningful efficacy with good tolerability as shown by improvements in both progression-free survival and overall survival compared with vemurafenib. These data suggest that the combination of encorafenib plus binimetinib is likely to become an important therapeutic option in patients with BRAF^V600-mutant melanoma.

FUNDING

Array BioPharma, Novartis.

Phase 1/2 study assessing the safety and efficacy of dabrafenib and trametinib combination therapy in Japanese patients with BRAF V600 mutation-positive advanced cutaneous melanoma

The combination of dabrafenib and trametinib demonstrated encouraging antitumor activity and tolerability, at initial analysis, in Japanese patients with BRAF V600 mutant advanced melanoma warranting further investigation. This study evaluated the safety and tolerability, pharmacokinetics (PK) and preliminary efficacy of dabrafenib 150 mg b.i.d. plus trametinib 2 mg q.d. in Japanese patients with BRAF V600E/K mutant solid tumors (phase 1) and melanoma (phase 2). Phase 1 was primarily intended to assess safety and tolerability as assessed by adverse events (AE), and the primary end-point in phase 2 was to assess confirmed overall response rate (ORR). The secondary end-points in phase 1 included PK, confirmed/unconfirmed ORR and duration of response (DOR). The secondary end-points in phase 2 were PK, unconfirmed ORR, DOR, safety and tolerability. A total of 12 cutaneous melanoma patients were enrolled in the study (six in phase 1 and six in phase 2) and received the combination therapy of dabrafenib and trametinib. Common AE (≥50.0%) included pyrexia (75%), increased aspartate aminotransferase (67%), peripheral edema (50%) and nasopharyngitis (50%). The investigator-assessed ORR was reported in five patients (83%) in phase 1 and was also reported in five patients (83%; 95% confidence interval, 35.9-99.6; P < 0.0001) in phase 2. Plasma concentrations of both dabrafenib and trametinib seemed to a reach steady state by week 3. Overall, efficacy and PK properties for the dabrafenib plus trametinib combination in Japanese patients were comparable with those seen in global studies.

PET/CT surveillance detects asymptomatic recurrences in stage IIIB and IIIC melanoma patients: a prospective cohort study

AJCC stage IIIB and IIIC melanoma patients are at risk for disease relapse or progression. The advent of effective systemic therapies has made curative treatment of progressive disease a possibility. As resection of oligometastatic disease can confer a survival benefit and as immunotherapy is possibly most effective in a low tumor load setting, there is a likely benefit to early detection of progression. The aim of this pilot study was to evaluate a PET/computed tomography (CT) surveillance schedule for resected stage IIIB and IIIC melanoma. From 1-2015, stage IIIB and IIIC melanoma patients at our institution underwent 6-monthly surveillance with PET/CT, together with 3-monthly S100B assessment. When symptoms or elevated S100B were detected, an additional PET/CT was performed. Descriptive statistics were used to evaluate outcomes for this surveillance schedule. Fifty-one patients were followed up, 27 patients developed a recurrence before surveillance imaging, five were detected by an elevated S100B, and one patient was not scanned according to protocol. Eighteen patients were included. Thirty-two scans were acquired. Eleven relapses were suspected on PET/CT. Ten scans were true positive, one case was false positive, and one case was false negative. All recurrences detected by PET/CT were asymptomatic at that time, with a normal range of S100B. The number of scans needed to find one asymptomatic relapse was 3.6. PET/CT surveillance imaging seems to be an effective strategy for detecting asymptomatic recurrence in stage IIIB and IIIC melanoma patients in the first year after complete surgical resection.

Targeted drug delivery to melanoma

Melanoma derived from melanocytes is the most aggressive genre of skin cancer. Although the considerable advancement in the study of human cancer biology and drug discovery, most advanced melanoma patients are inevitably unable to be cured. With the emergence of nanotechnology, the use of nano-carriers is widely expected to alter the landscape of melanoma treatment. In this review, we will discuss melanoma biology, current treatment options, mechanisms behind drug resistance, and nano-based solutions for effective anti-cancer therapy, followed by challenges and perspectives in both pre-clinical and clinical settings.

Dabrafenib plus Trametinib: a Review in Advanced Melanoma with a BRAF (V600) Mutation

The BRAF inhibitor dabrafenib (Tafinlar(®)) and the MEK inhibitor trametinib (Mekinist(®)) are indicated, as monotherapy or in combination with each other, for the treatment of patients with unresectable or metastatic melanoma with a BRAF (V600) mutation. This article reviews the therapeutic efficacy and tolerability of combination treatment with dabrafenib and trametinib in this indication and summarizes relevant pharmacological data. Dabrafenib plus trametinib significantly prolonged progression-free survival (PFS) and overall survival (OS), improved objective response rates (ORRs) and preserved health-related quality of life (HR-QOL) to a greater extent than dabrafenib (in the double-blind COMBI-d study) and vemurafenib (in the open-label COMBI-v study) in two large, randomized, phase III studies in treatment-naïve patients with unresectable or metastatic melanoma with BRAF (V600E/K) mutation. Limited treatment benefit with the combination was also seen in patients who had progressed on prior BRAF inhibitor therapy, as indicated by ORRs of ≤ 15 % and stable disease in ≤ 50 % of patients in small phase I and II studies. Combination therapy did not increase overall toxicity relative to dabrafenib or vemurafenib monotherapy, with most adverse events (AEs) mild or moderate in severity and generally manageable. Fewer skin-related AEs (e.g. cutaneous malignancies, hyperkeratinosis and hand-foot syndrome) were reported with combination therapy than with dabrafenib or vemurafenib, probably because of reduced paradoxical activation of the MAPK pathway. Thus, dabrafenib plus trametinib provides an important treatment option for patients with BRAF (V600) mutation-positive unresectable or metastatic melanoma.

Metastatic melanoma moves on: translational science in the era of personalized medicine

Progress in understanding and treating metastatic melanoma is the result of decades of basic and translational research as well as the development of better in vitro tools for modeling the disease. Here, we review the latest therapeutic options for metastatic melanoma and the known genetic and non-genetic mechanisms of resistance to these therapies, as well as the in vitro toolbox that has provided the greatest insights into melanoma progression. These include next-generation sequencing technologies and more complex 2D and 3D cell culture models to functionally test the data generated by genomics approaches. The combination of hypothesis generating and hypothesis testing paradigms reviewed here will be the foundation for the next phase of metastatic melanoma therapies in the coming years.

The Treatment of Melanoma Brain Metastases

Melanoma is the malignancy with the highest rate of dissemination to the central nervous system once it metastasizes. Until recently, the prognosis of patients with melanoma brain metastases (MBM) was poor. In recent years, however, the prognosis has improved due to high-resolution imaging that facilitates early detection of small asymptomatic brain metastases and early intervention with local modalities such as stereotactic radiosurgery. More recently, a number of systemic therapies have been approved by the Food and Drug Administration for metastatic melanoma, resulting in improved survival for many MBM patients. Registration trials for these newer therapies excluded patients with untreated brain metastases, and a number of studies specifically tailored to this population of patients have been conducted or are underway. Herein, we review contemporary locoregional and systemic therapies and describe the unique challenges posed by treatment of brain metastases, such as radionecrosis, cerebral edema, and pseudoprogression. Since the number of systemic and combined modality clinical trials has increased, we expect that the treatment landscape for patients with melanoma brain metastasis will change dramatically. In addition to ongoing clinical trials, which show great promise, we conclude that our understanding of intracranial metastasis remains quite limited. In addition to inter-disciplinary, multi-modality studies, bench-side work to better understand the process of cerebrotropism is needed to fuel more drug development and further improve outcomes.

Dabrafenib plus trametinib in patients with BRAFV600-mutant melanoma brain metastases (COMBI-MB): a multicentre, multicohort, open-label, phase 2 trial

BACKGROUND

Dabrafenib plus trametinib improves clinical outcomes in BRAFV600-mutant metastatic melanoma without brain metastases; however, the activity of dabrafenib plus trametinib has not been studied in active melanoma brain metastases. Here, we report results from the phase 2 COMBI-MB trial. Our aim was to build on the current body of evidence of targeted therapy in melanoma brain metastases through an evaluation of dabrafenib plus trametinib in patients with BRAFV600-mutant melanoma brain metastases.

METHODS

This ongoing, multicentre, multicohort, open-label, phase 2 study evaluated oral dabrafenib (150 mg twice per day) plus oral trametinib (2 mg once per day) in four patient cohorts with melanoma brain metastases enrolled from 32 hospitals and institutions in Europe, North America, and Australia: (A) BRAFV600E-positive, asymptomatic melanoma brain metastases, with no previous local brain therapy, and an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1; (B) BRAFV600E-positive, asymptomatic melanoma brain metastases, with previous local brain therapy, and an ECOG performance status of 0 or 1; (C) BRAFV600D/K/R-positive, asymptomatic melanoma brain metastases, with or without previous local brain therapy, and an ECOG performance status of 0 or 1; and (D) BRAFV600D/E/K/R-positive, symptomatic melanoma brain metastases, with or without previous local brain therapy, and an ECOG performance status of 0, 1, or 2. The primary endpoint was investigator-assessed intracranial response in cohort A in the all-treated-patients population. Secondary endpoints included intracranial response in cohorts B, C, and D. This study is registered with ClinicalTrials.gov, number NCT02039947.

FINDINGS

Between Feb 28, 2014, and Aug 5, 2016, 125 patients were enrolled in the study: 76 patients in cohort A; 16 patients in cohort B; 16 patients in cohort C; and 17 patients in cohort D. At the data cutoff (Nov 28, 2016) after a median follow-up of 8·5 months (IQR 5·5-14·0), 44 (58%; 95% CI 46-69) of 76 patients in cohort A achieved an intracranial response. Intracranial response by investigator assessment was also achieved in nine (56%; 95% CI 30-80) of 16 patients in cohort B, seven (44%; 20-70) of 16 patients in cohort C, and ten (59%; 33-82) of 17 patients in cohort D. The most common serious adverse events related to study treatment were pyrexia for dabrafenib (eight [6%] of 125 patients) and decreased ejection fraction (five [4%]) for trametinib. The most common grade 3 or worse adverse events, regardless of study drug relationship, were pyrexia (four [3%] of 125) and headache (three [2%]).

INTERPRETATION

Dabrafenib plus trametinib was active with a manageable safety profile in this melanoma population that was consistent with previous dabrafenib plus trametinib studies in patients with BRAFV600-mutant melanoma without brain metastases, but the median duration of response was relatively short. These results provide evidence of clinical benefit with dabrafenib plus trametinib and support the need for additional research to further improve outcomes in patients with melanoma brain metastases.

FUNDING

Novartis.

Targeting BRAF-Mutant Non-Small Cell Lung Cancer: From Molecular Profiling to Rationally Designed Therapy

Non-small cell lung cancer (NSCLC) remains the leading cause of cancer-related deaths globally. However, the identification of oncogenic driver alterations involved in the initiation and maintenance of NSCLC, such as epidermal growth factor receptor mutations and anaplastic lymphoma kinase translocation, has led to the development of novel therapies that directly target mutant proteins and associated signaling pathways, resulting in improved clinical outcomes. As sequencing techniques have improved, the molecular heterogeneity of NSCLC has become apparent, leading to the identification of a number of potentially actionable oncogenic driver mutations. Of these, one of the most promising therapeutic targets is B-Raf proto-oncogene, serine/threonine kinase (BRAF). Mutations in BRAF, observed in 2%-4% of NSCLCs, typically lead to constitutive activation of the protein and, as a consequence, lead to activation of the mitogen-activated protein kinase signaling pathway. Direct inhibition of mutant BRAF and/or the downstream mitogen-activated protein kinase kinase (MEK) has led to prolonged survival in patients with BRAF-mutant metastatic melanoma. This comprehensive review will discuss the clinical characteristics and prognostic implications of BRAF-mutant NSCLC, the clinical development of BRAF and MEK inhibitors from melanoma to NSCLC, and practical considerations for clinicians involving BRAF mutation screening and the choice of targeted therapy.

IMPLICATIONS FOR PRACTICE

Personalized medicine has begun to provide substantial benefit to patients with oncogene-driven non-small cell lung cancer (NSCLC). However, treatment options for patients with oncogenic driver mutations lacking targeted treatment strategies remain limited. Direct inhibition of mutant B-Raf proto-oncogene, serine/threonine kinase (BRAF) and/or downstream mitogen-activated protein kinase kinase (MEK) has the potential to change the course of the disease for patients with BRAF-mutant NSCLC, as it has in BRAF-mutant melanoma. Optimization of screening strategies for rare mutations and the choice of appropriate agents on an individual basis will be key to providing timely and successful intervention.

Management of Treatment-Related Adverse Events with Agents Targeting the MAPK Pathway in Patients with Metastatic Melanoma

Tremendous progress has been made in the clinical landscape of advanced-stage BRAF V600-mutant melanoma treatment over the past 5 years. Targeted therapies that inhibit specific steps of the mitogen-activated protein kinase pathway have been shown to provide significant overall treatment benefit in patients with this difficult-to-treat disease. Combination therapy with BRAF and MEK inhibitors (dabrafenib plus trametinib or vemurafenib plus cobimetinib, respectively) has become standard of care. These agents are administered until disease progression or unacceptable toxicity occurs; thus, some patients may remain on maintenance therapy for an extended period of time, while toxicities may result in early discontinuation in other patients. Because the goal of treatment is to prolong survival with minimal impairment of quality of life, drug-related adverse events (AEs) require prompt management to ensure that patients derive the best possible benefit from therapy. Proper management depends on an understanding of which AEs are most likely BRAF or MEK inhibitor associated, thus providing a rationale for dose modification of the appropriate drug. Additionally, the unique safety profile of the chosen regimen may influence patient selection and monitoring. This review discusses the toxicity profiles of these agents, with a focus on the most commonly reported and serious AEs. Here, we offer practical guidance derived from our clinical experience for the optimal management of key drug-related AEs.

IMPLICATIONS FOR PRACTICE

Targeted therapy with BRAF plus MEK inhibitors has become the standard of care for patients with advanced-stage BRAF V600-mutant metastatic melanoma. To provide optimal therapeutic benefit to patients, clinicians need a keen understanding of the toxicity profiles of these drugs. Prompt identification and an understanding of which adverse events are most likely BRAF or MEK inhibitor associated provide a rationale for appropriate therapy adjustments. Practical recommendations derived from clinical experience are provided for management of key drug-related toxicities.

A systematic review and network meta-analysis of immunotherapy and targeted therapy for advanced melanoma

Immune and BRAF‐targeted therapies have changed the therapeutic scenario of advanced melanoma, turning the clinical decision‐making a challenging task. This Bayesian network meta‐analysis assesses the role of immunotherapies and targeted therapies for advanced melanoma. We retrieved randomized controlled trials testing immune, BRAF‐ or MEK‐targeted therapies for advanced melanoma from electronic databases. A Bayesian network model compared therapies using hazard ratio (HR) for overall survival (OS), progression‐free survival (PFS), and odds ratio (OR) for response rate (RR), along with 95% credible intervals (95% CrI), and probabilities of drugs outperforming others. We assessed the impact of PD‐L1 expression on immunotherapy efficacy. Sixteen studies evaluating eight therapies in 6849 patients were analyzed. For OS, BRAF‐MEK combination and PD‐1 single agent ranked similarly and outperformed all other treatments. For PFS, BRAF‐MEK combination surpassed all other options, including CTLA‐4‐PD‐1 dual blockade hazard ratio (HR: 0.56; 95% CrI: 0.33–0.97; probability better 96.2%), whereas BRAF single agent ranked close to CTLA‐4‐PD‐1 blockade. For RR, BRAF‐MEK combination was superior to all treatments including CTLA‐4‐PD‐1 (OR: 2.78; 1.18–6.30; probability better 97.1%). No OS data were available for CTLA‐4‐PD‐1 blockade at the time of systematic review, although PFS and RR results suggested that this combination could also bring meaningful benefit. PD‐L1 expression, as presently defined, failed to inform patient selection to PD‐1‐based immunotherapy. BRAF‐MEK combination seemed an optimal therapy for BRAF‐mutated patients, whereas PD‐1 inhibitors seemed optimal for BRAF wild‐type patients. Longer follow‐up is needed to ascertain the role of CTLA‐4‐PD‐1 blockade. Immunotherapy biomarkers remain as an unmet need.

Targeted agents and immunotherapies: optimizing outcomes in melanoma

Treatment options for patients with metastatic melanoma, and especially BRAF-mutant melanoma, have changed dramatically in the past 5 years, with the FDA approval of eight new therapeutic agents. During this period, the treatment paradigm for BRAF-mutant disease has evolved rapidly: the standard-of-care BRAF-targeted approach has shifted from single-agent BRAF inhibition to combination therapy with a BRAF and a MEK inhibitor. Concurrently, immunotherapy has transitioned from cytokine-based treatment to antibody-mediated blockade of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and, now, the programmed cell-death protein 1 (PD-1) immune checkpoints. These changes in the treatment landscape have dramatically improved patient outcomes, with the median overall survival of patients with advanced-stage melanoma increasing from approximately 9 months before 2011 to at least 2 years - and probably longer for those with BRAF-V600-mutant disease. Herein, we review the clinical trial data that established the standard-of-care treatment approaches for advanced-stage melanoma. Mechanisms of resistance and biomarkers of response to BRAF-targeted treatments and immunotherapies are discussed, and the contrasting clinical benefits and limitations of these therapies are explored. We summarize the state of the field and outline a rational approach to frontline-treatment selection for each individual patient with BRAF-mutant melanoma.

Combination Treatment of Patients with BRAF-Mutant Melanoma: A New Standard of Care

Raf-mitogen-activated protein kinase (Raf-MAPK) pathway inhibition with the BRAF inhibitors vemurafenib and dabrafenib, alone or in combination with a MEK inhibitor, has become a standard therapeutic approach in patients with BRAF-mutated metastatic melanoma. Both vemurafenib and dabrafenib have shown good safety and efficacy as monotherapy compared with chemotherapy. However, the duration of response is limited in the majority of patients treated with BRAF inhibitor monotherapy because of the development of acquired resistance. The addition of a MEK inhibitor can improve blockade of the MAPK pathway and may help to overcome resistance and thereby prolong efficacy, as well as reduce cutaneous toxicity. Combinations of BRAF inhibitors and MEK inhibitors (dabrafenib plus trametinib and vemurafenib plus cobimetinib) have been approved for the treatment of BRAF-mutant metastatic melanoma and may become a new standard of care. However, acquired resistance is still a significant concern with BRAF and MEK inhibitor combination therapy, and other strategies are being investigated, including the use of sequential and intermittent schedules. The combination of BRAF or MEK inhibitors with immunotherapy has been shown to hold considerable promise, with several combinations being evaluated in clinical trials. Preliminary results from clinical trials involving triple combination therapy with BRAF-MEK inhibitors and anti-PD-L1 antibodies appear promising and may indicate a new strategy to treat patients with BRAF-mutated metastatic melanoma. Biomarkers are needed to help identify patients with BRAFV600 mutations most likely to benefit from first-line BRAF/MEK inhibitor therapy rather than immunotherapy and vice versa.

Indirect treatment comparison of dabrafenib plus trametinib versus vemurafenib plus cobimetinib in previously untreated metastatic melanoma patients

Background

Metastatic melanoma is an aggressive form of skin cancer with a high mortality rate and the fastest growing global incidence rate of all malignancies. The introduction of BRAF/MEK inhibitor combinations has yielded significant increases in PFS and OS for melanoma. However, at present, no direct comparisons between different BRAF/MEK combinations have been conducted. In light of this, an indirect treatment comparison was performed between two BRAF/MEK inhibitor combination therapies for metastatic melanoma, dabrafenib plus trametinib and vemurafenib plus cobimetinib, in order to understand the relative efficacy and toxicity profiles of these therapies.

Methods

A systematic literature search identified two randomized trials as suitable for indirect comparison: the coBRIM trial of vemurafenib plus cobimetinib versus vemurafenib and the COMBI-v trial of dabrafenib plus trametinib versus vemurafenib. The comparison followed the method of Bucher et al. and analyzed both efficacy (overall survival [OS], progression-free survival [PFS], and overall response rate [ORR]) and safety outcomes (adverse events [AEs]).

Results

The indirect comparison revealed similar efficacy outcomes between both therapies, with no statistically significant difference between therapies for OS (hazard ratio [HR] 0.94, 95% confidence interval [CI] 0.68 − 1.30), PFS (HR 1.05, 95% CI 0.79 − 1.40), or ORR (risk ratio [RR] 0.90, 95% CI 0.74 − 1.10). Dabrafenib plus trametinib differed significantly from vemurafenib plus cobimetinib with regard to the incidence of treatment-related AE (RR 0.92, 95% CI 0.87 − 0.97), any AE grade ≥3 (RR 0.71, 95% CI 0.60 − 0.85) or dose interruption/modification (RR 0.77, 95% CI 0.60 − 0.99). Several categories of AEs occurred significantly more frequently with vemurafenib plus cobimetinib, while some occurred significantly more frequently with dabrafenib plus trametinib. For severe AEs (grade 3 or above), four occurred significantly more frequently with vemurafenib plus cobimetinib and no severe AE occurred significantly more frequently with dabrafenib plus trametinib.

Conclusions

This indirect treatment comparison suggested that dabrafenib plus trametinib had comparable efficacy to vemurafenib plus cobimetinib but was associated with reduced adverse events.

Phase II study of vemurafenib followed by ipilimumab in patients with previously untreated BRAF-mutated metastatic melanoma

BACKGROUND

Ipilimumab (IPI), an anti-CTLA-4 antibody, and vemurafenib (VEM), a BRAF inhibitor, have distinct mechanisms of action and shared toxicities (e.g., skin, gastrointestinal [GI] and hepatobiliary disorders) that may preclude concomitant administration. Concurrent administration of IPI and VEM previously showed significant dose-limiting hepatotoxicity in advanced melanoma. This single-arm, open-label, phase II study evaluated a sequencing strategy with these two agents in previously untreated patients with BRAF-mutated advanced melanoma.

METHODS

This study was divided into two parts. During Part 1 (VEM1-IPI), patients received VEM 960 mg twice daily for 6 weeks followed by IPI 10 mg/kg every 3 weeks for 4 doses (induction), then every 12 weeks (maintenance) beginning at week 24 until disease progression or unacceptable toxicity. During Part 2 (VEM2), patients who progressed after IPI received VEM at their previously tolerated dose. The primary objective was to estimate the incidence of grade 3/4 drug-related skin adverse events (AEs) during VEM1-IPI.

RESULTS

All patients who were initially treated with VEM (n = 46) received IPI induction therapy; 8 received IPI maintenance and 19 were treated during VEM2. During VEM1-IPI, the incidence of grade 3/4 drug-related AEs associated with the skin, GI tract, and hepatobiliary system was 32.6 %, 21.7 %, and 4.3 %, respectively. There were no drug-related deaths. At a median follow-up of 15.3 months, median overall survival was 18.5 months. Median progression-free survival was 4.5 months.

CONCLUSIONS

VEM (960 mg twice daily for 6 weeks) followed by IPI 10 mg/kg has a manageable safety profile. The benefits/risks of BRAF inhibitors followed by immunotherapy should be evaluated further in light of continuing developments in treatment options for metastatic melanoma.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01673854 (CA184-240) Registered 24 August 2012.

Improving patient outcomes to targeted therapies in melanoma

INTRODUCTION

The arrival of targeted therapies has led to significant improvements in clinical outcomes for patients with BRAFV600 mutated advanced melanoma over the past five years.

AREAS COVERED

In several clinical trials, BRAF and MEK inhibitors have shown improvement in progression free and overall survival, along with much higher tumor response rates in comparison to chemotherapy, with the combination of these drugs superior to monotherapy. These agents are also being tested in earlier-stage patients, in addition to alternative dosing regimens and in combinations with other therapeutics. Efforts are also ongoing to expand the success found with targeted therapies to other subtypes of melanoma, including NRAS and c-kit mutated melanomas, uveal melanomas, and BRAF/NRAS wild type melanomas. Expert Commentary: We aim to provide an overview of clinical outcomes with targeted therapies in melanoma patients.

Immunotherapies and novel combinations: the focus of advances in the treatment of melanoma

Since 2011, the approval of four different classes of novel drugs (the anti-CTLA-4 agent, ipilimumab; BRAF inhibitors [BRAFi]; MEK inhibitors [MEKi]; and the anti-PD-1 drug, pembrolizumab) has revolutionized the care of advanced melanoma, with the disease becoming a model for the development of new treatments for other types of cancer. Further advances in the treatment of melanoma represented some of the key highlights of the European Society of Medical Oncology (ESMO) 2014 congress. The first phase III trial of an anti-PD-1 agent to report the CA209-037 study included 405 patients with metastatic melanoma previously treated with ipilimumab who were randomized 2:1 to receive nivolumab 3 mg/kg every 2 weeks or investigator's choice chemotherapy. Nivolumab was associated with a higher response rate than chemotherapy and was well tolerated, with adverse events mostly low grade and manageable using recommended treatment algorithms. New data on other immunotherapies, namely ipilimumab and pembrolizumab, were also reported. In addition, outside of immunotherapy, combination approaches involving targeted agents were also a major focus of ESMO this year, with two major phase III studies of combined BRAF inhibition and MEK inhibition being reported. Overall, new clinical trial findings reported at ESMO further endorse the view that melanoma, given the continued development of novel, effective compounds, can accurately be described as the most "dynamic" field of oncology at present.