A Retrospective Analysis of Dabrafenib and/or Dabrafenib Plus Trametinib Combination in Patients with Metastatic Melanoma to Characterize Patients with Long-Term Benefit in the Individual Patient Program (DESCRIBE III)

Outcomes in patients with BRAFV600-mutated melanoma and brain metastases at baseline treated with dabrafenib plus trametinib

BACKGROUND

Brain metastases (BM) and lactate dehydrogenase (LDH) levels above the upper limit of normal (ULN) are associated with poor prognosis in patients with melanoma. Although treatment with the BRAF inhibitor dabrafenib and the MEK inhibitor trametinib have demonstrated long-term clinical benefit in patients with melanoma, data on their efficacy in patients with BM are limited.

METHODS

DESCRIBE Italy is an observational, retrospective, real-world study evaluating dabrafenib plus trametinib in 499 patients with BRAFV600-mutant stage III unresectable or stage IV melanoma from various sites across Italy. Here, we analyzed the clinical outcomes for the subgroup of patients receiving first-line treatment and presenting with BM at diagnosis and assessed the impact of predictive factors such as LDH levels and the presence of other metastases on median progression-free survival (mPFS).

RESULTS

Overall, 325 evaluable patients were on first-line therapy and are the focus of this analysis; of these, 76 patients (23.4%) had BM at baseline. mPFS was lower for patients with BM at baseline compared with overall patients (8.7 months vs 9.3 months, respectively). Patients with BM at diagnosis and LDH >ULN had a considerably shorter mPFS compared with patients with LDH ⩽ULN (5.3 months vs 9.9 months, respectively). mPFS was noticeably longer for patients with cerebral metastases only compared with patients with cerebral and other metastases (15.0 months vs 8.7 months, respectively).

CONCLUSIONS

Dabrafenib plus trametinib showed effectiveness in a real-world population of patients with advanced BRAFV600-mutated melanoma and BM at baseline, supporting its use in this population with poor outcomes.

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.

The Pattern of Progression to First-Line Treatment with Dabrafenib and Trametinib in Patients with Unresectable or Metastatic, BRAF-Mutated, Cutaneous Melanoma: Results of the Observational T-WIN Study

In patients with B-RAF-mutated cutaneous melanoma, targeted therapies are the treatment of choice to achieve a rapid response. In this multicentric, prospective, observational study, patients with B-RAF-mutated cutaneous melanoma who were treated with dabrafenib and trametinib were categorized in two cohorts (cohort A: limited disease (n = 104) and cohort B: bulky disease (n = 97)) according to lactate dehydrogenase levels. The primary endpoint was the progression pattern; the secondary endpoints were overall survival (OS), progression-free survival (PFS), and safety data. From baseline to time of progression, there was a progression from nodal to other sites of disease in cohort A and from skin and nodal to other sites in cohort B. In both the cohorts, the number of involved organs and metastases at each location decreased. The median OS was 32.4 months (95% CI: 20.1 months (not estimable)) for cohort A, and 10.5 months (95% CI: 8.3–14.4 months) for cohort B; median PFS was 12.4 months (95% CI: 10.9–17.0 months) for cohort A, and 8.1 months (95% CI: 6.3–9.4 months) for cohort B. No new safety signals were reported. This study describes the patterns of first-line treatment progression with dabrafenib and trametinib in Italian clinical practice. The effectiveness and safety data were consistent with previous trials and extended to a real-world heterogeneous population.

Safety of combining dabrafenib plus trametinib in elderly BRAF V600 mutation-positive advanced melanoma patients: real-world data analysis of Spanish patients (ELDERLYMEL)

Efficacy and safety of dabrafenib and trametinib in metastatic melanoma have been demonstrated in two-phase III and one-phase I/II clinical trials. However, patients at least 75 years old (y.o.) were largely underrepresented. Additionally, the safety profile of dabrafenib and trametinib based on age is unknown. ELDERLYMEL is a retrospective noninterventional multicenter study, describing the effectiveness and safety of at least 75 y.o. patients compared with less than 75 y.o. patients with advanced BRAF V600-mutated melanoma treated with dabrafenib plus trametinib or dabrafenib monotherapy. A total of 159 patients were included, 130 less than 75 y.o. and 29 at least 75 y.o. Clinical features were similar between the groups, except in the number of comorbidities, number of metastatic sites, Eastern Cooperative Oncology Group (ECOG) performance status, and BRAF V600-mutation type. Five patients per group received dabrafenib monotherapy. There were no differences in adverse events (AEs) rate or grade between the groups. However, AE profiles were different between the groups, being pyrexia infrequent in patients at least 75 y.o. (13.8% vs. 42.3%; P = 0.005). Dabrafenib and trametinib dose intensities were lower in at least 75 y.o. patients (P = 0.018 and P = 0.020), but there were no differences in effectiveness between the groups. Finally, in a multivariate analysis, sex (female) was the only variable independently associated with an increased risk of AE grade ≥3. Data from the ELDERLYMEL study demonstrate that dabrafenib plus trametinib is safe and effective in at least 75 y.o. patients with advanced BRAF V600-mutated melanoma without increasing toxicity. Additionally, we describe a different safety profile depending on age and sex.

Long-Term Outcomes of Targeted Therapy after First-Line Immunotherapy in BRAF-Mutated Advanced Cutaneous Melanoma Patients—Real-World Evidence

Background: Currently, limited data on targeted therapy and immunotherapy sequencing in patients with BRAF-mutant melanoma is available. Targeted therapy and immunotherapy are expected to be comparable in terms of overall survival (OS) when used as second-line therapies; therefore, understanding the characteristics of patients who completed sequential treatment is needed. Methods: The primary objective of this study was to analyze the efficacy of BRAFi/MEKi activity as second-line therapy in patients with advanced melanoma. We also aimed to describe the clinical characteristics of patients with advanced melanoma who were treated sequentially with immunotherapy and targeted therapy. We enrolled 97 patients treated between 1st December 2015 and 31st December 2020 with first-line immunotherapy with programmed cell death 1 (PD-1) checkpoint inhibitors; and for the second-line treatment with at least one cycle of BRAFi/MEKi therapy with follow-up through 31 January 2022. Results: Median OS since first-line treatment initiation was 19.9 months and 12.8 months since initiation of BRAFi/MEKi treatment. All BRAFi/MRKi combinations were similarly effective. Median progression free survival (PFS) was 7.5 months since initiation of any BRAFi/MEKi treatment. Conclusions: BRAFi/MEKi therapy is effective in the second-line in advanced and metastatic melanoma patients. For the first time, the efficacy of all BRAFi/MEKi combinations as second-line therapy is shown.

Retrospective Chart Review of Dabrafenib Plus Trametinib in Patients with Metastatic BRAF V600-Mutant Melanoma Treated in the Individual Patient Program (DESCRIBE Italy)

BACKGROUND

Real-world data on extended follow-up of patients with BRAF V600-mutant metastatic melanoma are limited. We investigated dabrafenib plus trametinib (dab + tram) outside of a clinical trial setting (Individual Patient Program; DESCRIBE Italy).

OBJECTIVE

To describe the baseline features, treatment patterns, efficacy, and safety outcomes in patients with BRAF V600-mutant unresectable or metastatic melanoma who had received dab + tram as part of the Managed Access Program (MAP) in Italy.

PATIENTS AND METHODS

An observational, retrospective chart review was conducted in Italian patients with BRAF V600-mutant unresectable stage III/IV melanoma receiving dab + tram as part of the MAP. Baseline features, treatment patterns, efficacy, and safety outcomes were evaluated.

RESULTS

Overall, 499 patients were included in this analysis. BRAF V600E mutation was seen in 81.4% of patients. Overall response rate achieved in 243 of the 390 evaluable patients was 62.3% (95% CI 57.5-67.1). Median progression-free survival (PFS) was 9.3 months (95% CI 8.6-10.6). Subgroup analyses revealed that patients with normal lactate dehydrogenase (LDH) and ≤ three metastatic sites without brain metastases at baseline had better outcomes. With normal LDH at baseline, median PFS for patients with one or two metastatic sites other than cerebral was 18 months. No new safety signals were observed. Treatment was permanently discontinued because of treatment-emergent adverse events (TEAEs) in 9.2% of patients, and pyrexia (27.3%) was the most common TEAE, with a lower incidence than that in the phase 3 studies of dab + tram.

CONCLUSION

Treatment of BRAF V600E-mutant metastatic melanoma with dab + tram in the real-world setting was effective and safe, including the unselected population with several patients having a high tumor burden - concordant with the results of the pivotal phase 3 studies of dab + tram.

Treatment of Advanced Metastatic Melanoma

The introduction in clinical practice of new drug compounds both targeted therapies anti-BRAF and checkpoint inhibitors have largely improved our potential to manage advanced metastatic melanoma patients. This has led to a significant improvement in terms of response rates and particularly in the overall survival (OS). The long-term results of trials with follow-up data of patients treated with targeted or immunotherapies reported median OS rates around 24 months, with 5-year survival rates around 35-40%. As to the drugs currently available and reimbursed by the Italian National Health System, 3 combinations of anti-BRAF/anti-MEK inhibitors are available (dabrafenib/trametinib, vemurafenib/cobimetinib and the most recently introduced encorafenib/binimetinib). As for checkpoint inhibitors, first line immunotherapy is represented by anti-PD1 blockers (nivolumab and pembrolizumab), whilst the anti-CTLA-4 ipilimumab can be used as second line immunotherapy. The decision-making factors that define the best treatment approach in stage IV patients with metastatic melanoma include the mutation pattern, performance status, high/low tumor load, brain metastases, progression pattern (low/fast), and availability of clinical trials. This review will analyze the current therapeutic tools adopted for the treatment of metastatic melanoma patients. It will then focus on the latest results obtained by novel treatments (checkpoint inhibitors and targeted therapies) which can be used in the clinical daily practice.