Effects of CTLA-4 Single Nucleotide Polymorphisms on Toxicity of Ipilimumab-Containing Regimens in Patients With Advanced Stage Melanoma.

Single nucleotide polymorphisms (SNPs) in the cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) gene, an inhibitor of T-cell priming, are associated with auto and alloimmunity. Studies implied a role for these SNPs as surrogate markers for immunotherapy-outcome in patients with melanoma. However, no predictive SNPs are defined to date. We analyzed different CTLA-4 SNPs in a large multicenter cohort of patients with ipilimumab-treated melanoma and investigated possible correlations with treatment-related outcomes. Archival blood and/or tumor tissue samples were collected from 361 patients with advanced-stage ipilimumab-treated (±nivolumab) in 6 Swiss and Dutch hospitals. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry based DNA genotyping was performed for 10 different CTLA-4 SNPs: 49A>G, CT60G>A, Jo27T>C, Jo30G>A, Jo31G>T, -658C>T, -1722T>C, -1661A>G, 318C>T, and C>T rs1863800. Associations between different allele genotypes and occurrence of grade ≥3 adverse events (AEs) and survival were tested using univariable logistic regressions or Cox proportional hazard models. 262/361 (73%) patients could be analyzed; 65% of those were males, the median age was 58 years, 39% showed a partial or complete response, and 65% had ≥1 AEs. A TT-genotype of -1722T>C SNP was significantly associated with a lower incidence of grade ≥3 AEs ( P = 0.049), whereas the GG-genotype of CT60G>A correlated with a higher incidence of grade ≥3 AEs ( P = 0.026). The TT-genotype of Jo27T>C SNP ( P = 0.056) and GG-genotype of Jo31G>T ( P = 0.046) were associated with overall survival. CTLA-4 SNPs might predict treatment-related outcomes in patients with melanoma receiving ipilimumab. Confirmatory studies are needed to fully exploit those findings as predictive biomarkers for ipilimumab AEs.

The features and management of acquired resistance to PD1-based therapy in metastatic melanoma.

BACKGROUND: Anti-PD-1 therapy (PD1) either alone or with anti-CTLA-4 (CTLA4), has high initial response rates, however 20% of patients (pts) with complete response (CR) and 30% with partial response (PR) within 12 months of treatment experience subsequent disease progression by 6 years. The nature and optimal management of this acquired resistance (AR) remains unknown. METHODS: Pts from 16 centres who responded to PD1-based therapy and who later progressed were examined. Demographics, disease characteristics and subsequent treatments were evaluated. RESULTS: 299 melanoma pts were identified, median age 64y, 44% BRAFV600m. 172 (58%) received PD1 alone, 114 (38%) PD1/CTLA4 and 13 (4%) PD1 and an investigational drug. 90 (30%) pts had CR, 209 (70%) PR. Median time to AR was 12.6 mo (95% CI, 11.3, 14.2). Most (N = 193, 65%) progressed in a single organ site, and in a solitary lesion (N = 151, 51%). The most frequent sites were lymph nodes (38%) and brain (25%). Management at AR included systemic therapy (ST, 45%), local therapy (LT) +ST (31%), LT alone (21%), or observation (3%). There was no statistical difference in PFS2 or OS based on management, however, PFS2 was numerically superior for pts treated with ST alone who progressed off PD1 therapy than those who progressed on PD1 (2-year PFS2 42% versus 25%, p = 0.249). mOS from AR was 38.0 months (95% CI, 29.5-NR); longer in single-site versus multi-site progression (2-year OS 70% vs 54%, p < 0·001). CONCLUSIONS: Acquired resistance to PD1 therapy in melanoma is largely oligometastatic, and pts may have a favorable survival outcome following salvage treatment.

Treatment reality of patients with BRAF-mutant advanced/metastatic melanoma in Switzerland in the era of choice.

Cutaneous melanoma represents a major cause of cancer death in Europe. Without adequate therapy, the 5-year survival rate is 15-20% in distant metastatic disease. Evaluating the status quo of treatment standards in advanced melanoma and rationale for therapy decisions in Switzerland between January 2016 and September 2018. In this retrospective, anonymized registry, data of male and female patients with unresectable advanced/metastatic BRAF-positive cutaneous melanoma treated in first-, second- and third-line with registered substances were analyzed using descriptive statistics. Forty-one patients (56.1% male) were included providing a total of 70 treatment lines (first-line: n = 41; second-line: n = 18; and third-line: n = 11). Within the patients presenting with stage III or IV melanoma, immunotherapy with checkpoint inhibitors was more frequently administered as first-line treatment than targeted therapy (TT) (70.7% vs. 29.3%). Across all lines, patients received TT in 47.1% (predominantly combined BRAF-MEK-inhibition) and immunotherapy in 52.9% of the cases (anti-PD-1 monotherapy in 62.2% and anti-PD-1/anti-CTLA-4 combinations in 37.8%). Most commonly, the treatment type was switched from TT to immunotherapy or vice versa upon disease progression. The most frequent rationales for prescribing either TT or immunotherapy were physician's preference (40.0%) or remission pressure (28.6%), respectively. Disease progression led to treatment discontinuation more frequently than undesired events. Patients in Switzerland with unresectable advanced or metastatic BRAF-mutant melanoma predominantly receive guideline-recommended treatments. IO was used as predominant front-line therapy, with TT/immunotherapy switch being the predominant treatment principle. Sequencing studies are underway to identify the optimal treatment regimen for those patients. 32: 366-372 Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.