Late-onset adverse events of anti-PD1 therapy in melanoma patients: An observational study from MELBASE, a nationwide prospective cohort.

BACKGROUND: Late-onset adverse events (AEs) of anti-programmed cell death 1 (anti-PD1) antibodies have not been systematically described. OBJECTIVES: The purpose was to evaluate late-onset AEs in melanoma patients treated with anti-PD1 administered for at least 2 years in a real-life setting. METHODS: Patients were screened from MelBase, a French multicentric biobank dedicated to the prospective follow up of unresectable stage III or IV melanoma. The study included 119 patients who received anti-PD1 during at least 2 years from January 2013 to November 2019. Median follow up was 41.7 months (range, 25.2-57.5 months). Fifty-three patients received nivolumab and 66 patients received pembrolizumab. RESULTS: AEs occurred in 99 patients (83%) with a median time of 13.3 months (range, 0-53.9 months), including severe AEs (grade 3 or 4) in 30 patients (30%). Late-onset AEs, mostly grades 1 or 2, occurred in 51 (43%) patients and led to 5 (4%) hospitalizations, of which 4 were severe. Factors associated with late-onset AEs in multivariate analysis were early-onset AEs (within the first 2 years of treatment) and treatment duration (P = .02 and P = .03, respectively). CONCLUSIONS: Our data demonstrate the possibility of late-onset AEs occurring after 2 years of anti-PD1 therapy. Late-onset AEs appear frequently and were mostly mild or moderate. Early-onset AEs and prolonged anti-PD1 treatment may increase the risk of late-onset AEs.

Differential gradients of immunotherapy vs targeted therapy efficacy according to the sun-exposure pattern of the site of occurrence of primary melanoma: a multicenter prospective cohort study (MelBase).

Background: The tumor mutational burden (TMB) is high in melanomas owing to UV-induced oncogenesis. While a high TMB is a predictive biomarker of response to PD-1 inhibitors, it may be associated with the rise of resistant clones to targeted therapy over time. We hypothesized that survivals may depend on both the sun-exposure profile of the site of primary melanoma and the type of systemic treatment. Patients and methods: Patients were screened from MelBase, a multicenter biobank dedicated to the prospective follow-up of stage III/IV melanoma. All patients with a known cutaneous primary melanoma who received a 1st-line systemic treatment by immunotherapy or targeted therapy were included (2013-2019). Outcomes were progression-free survival (PFS) and overall survival (OS). Results: 973 patients received either anti PD-1(n=466), anti CTLA-4(n=143), a combination of both (n=118), or targeted therapies (n=246). Patients' characteristics at treatment initiation were: male (62%), median age of 62, AJCC stage IV (84%). Median follow-up was 15.5 months. The primary melanoma was located on chronically sun-exposed skin in 202 patients (G1: head neck), on intermittently sun-exposed skin in 699 patients (G2: trunk, arms, legs), and on sun-protected areas in 72 patients (G3: palms, soles). Median PFS was significantly higher in G1 under anti PD-1 treatment (8.7 months vs 3.3 and 3.4 months for G2 and G3, respectively) (p=0.011). PFS did not significantly differ in other groups. Similarly, median OS was significantly higher in G1 receiving 1st line anti PD-1 treatment (45.6 months vs 31.6 and 21.4 months for G2 and G3) (p=0.04), as opposed to 1st line targeted therapy (19.5 months vs 16.3 and 21.1 months for G1, G2 and G3 respectively). Conclusion: Our study confirms that immunotherapy with anti PD-1 is particularly recommended for melanomas originating from chronically sun-exposed areas, but this finding needs to be confirmed by further research.

Non-V600E/K BRAF Mutations in Metastatic Melanoma: Molecular Description, Frequency, and Effectiveness of Targeted Therapy in a Large National Cohort.

PURPOSE: Mitogen-activating protein kinase inhibitors (MAPKis) are largely used in V600E/K BRAF-mutated metastatic melanomas, but data regarding effectiveness of targeted therapy in patients with rare BRAF mutations and molecular description of these infrequent mutations are scarce. PATIENTS AND METHODS: A multicenter study was conducted on patients with metastatic melanoma harboring a well-identified mutation of BRAF and enrolled from March 2013 to June 2021 in the French nationwide prospective cohort MelBase. The molecular BRAF mutation pattern, response to MAPKis when applicable, and survival data were analyzed. RESULTS: Of 856 selected patients, 51 (6%) harbored a non-V600E/K BRAF mutation involving codons V600 (24 of 51, 47%; V600G 27.4%, V600R 15.6%), K601 (6 of 51, 11.7%), and L597 (4 of 51, 7.8%). An objective response to MAPKis either BRAF inhibitor (BRAFi) alone or combined with MEK inhibitor was achieved in 56% (353 of 631) of V600E/K, 58% (11 of 19) of non-E/K V600, and 22% (2 of 9) of non-V600 BRAF-mutated patients, with a median progression-free survival of 7.7, 7.8, and 2.8 months, respectively. Overall, objective response rate was higher with BRAFi + MEK inhibitor combination than with BRAFi in monotherapy for each subset. CONCLUSION: Rare BRAF mutations are not anecdotal in the metastatic melanoma population. Although data interpretation must remain careful owing to the limited size of some subsets of patients, non-E/K V600 BRAF mutations seem to confer a high sensitivity to targeted therapy, whereas MAPKis seem less effective in patients with non-V600 BRAF mutations. However, this strategy may be used as an alternative option in the case of immunotherapy failure in the latter population.

Impact of New Systemic Treatment and Radiotherapy in Melanoma Patients with Leptomeningeal Metastases.

IMPORTANCE: Few data are available on patients with leptomeningeal disease (LM) from melanoma treated with new systemic therapies. OBJECTIVE: To gain a better understanding of patients, disease characteristics, and therapeutic interventions in melanoma patients with LM in the era of new systemic treatment. DESIGN: Clinical characteristics, treatments, and survival of melanoma patients diagnosed with LM, isolated or associated with brain metastases, were collected. The Cox regression model assessed the influence of patient and melanoma characteristics on survival. SETTING: Monocentric, retrospective, real-life cohort of patients with LM from melanoma. PARTICIPANTS: All patients followed up at Saint-Louis University Hospital and diagnosed with LM between December 2013 and February 2020 were included. For each patient identified, a central review by dermato-oncologist and neuro-oncologist experts was performed to confirm the diagnosis of LM. EXPOSURE: Impact of new systemic therapies and radiotherapy. RESULTS: Among the 452 advanced melanoma patients followed at St Louis Hospital between 2013 and 2020, 41 patients with LM from melanoma were identified. Among them, 29 patients with a diagnosis of LM "confirmed" or "probable" after central neuro-oncologists reviewing were included. Nineteen patients had known melanoma brain metastases at LM diagnosis. Among the 27 patients treated with systemic therapy, 17 patients were treated with immunotherapy, 5 patients received targeted therapy, 1 was treated with chemotherapy, and 4 patients were treated with anti-PD-1 in combination with BRAF inhibitor. The median overall survival (OS) from LM diagnosis was 5.1 months. Median OS was 7.1 months for the 9 patients receiving systemic therapy combined with radiotherapy, and 3.2 months for the 20 patients not receiving combined radiotherapy. Elevated serum lactate dehydrogenase (LDH) (HR 1.44, 95% CI 1.09-1.90, p < 0.01) and presence of neurological symptoms at LM diagnosis (HR 2.96, 95% CI 1.25-6.99, p = 0.01) were associated with poor survival. At the time of data analysis, five patients were still alive with a median follow-up of 47.4 months and had persistent complete response. CONCLUSION: Targeted therapy and immunotherapy are promising new treatment options in LM from melanoma that can increase overall survival, and may induce long lasting remission in some patients.

Combined Therapy with Anti-PD1 and BRAF and/or MEK Inhibitor for Advanced Melanoma: A Multicenter Cohort Study.

Despite significant progress in melanoma survival, therapeutic options are still needed in case of progression under immune checkpoint inhibitors (ICI), and resistance to targeted therapies (TT) in BRAF-mutated melanomas. This study aimed to assess the safety of combined ICI and TT as a rescue line in real-life clinical practice. We conducted a study within the prospective French multicentric MelBase cohort, including patients treated with a combination of anti-PD1 (pembrolizumab/nivolumab) and BRAF inhibitor (BRAFi: dabrafenib/vemurafenib) and/or MEK inhibitors (MEKi: trametinib/cobimetinib) for BRAF mutated or wild-type advanced melanoma. Fifty-nine patients were included: 30% received the triple combination, 34% an anti-PD1 and BRAFi, and 36% an anti-PD1 and MEKi. Grade 3-4 adverse events occurred in 12% of patients. Permanent discontinuation or dose reduction of one of the treatments for toxicity was reported in 14% and 7% of patients, respectively. In the BRAF wild-type subgroup, treatment with MEKi and anti-PD1 induced a tumor control rate of 83% and median progression-free survival of 7.1 months. The combination of anti-PD1 and BRAFi and/or MEKi was a safe rescue line for advanced melanoma patients previously treated with ICI/TT. The benefit of these combinations, specifically anti-PD1 and MEKi in BRAF wild-type melanoma patients, needs to be prospectively studied.