Correlation between baseline characteristics and clinical outcome of patients with advanced melanoma treated with pembrolizumab (PEMBRO)

Background

The PD-1 blocking mAb pembrolizumab (PEMBRO) is approved for the treatment of patients (pts) with advanced melanoma. Correlation between baseline characteristics and outcome of pts treated outside of a prospective clinical trial has not been established.

Methods

Using Kaplan-Meier statistics, log-rank testing and multivariate Cox-regression analysis, correlations were investigated between baseline variables and PFS and OS in pts with advanced melanoma who received PEMBRO outside a clinical trial. An independent confirmatory cohort (CC) of pts from the Netherlands and Spain served to confirm correlations found in an exploratory Belgian cohort (EC). Additional data from 180 Scandinavian pts are being collected.

Results

All pts in the EC (N = 123) and CC (N = 165) received at least one administration of PEMBRO (2 mg/kg q3wks). Baseline characteristics of the total cohort (TC) (N = 288) were: median age 60y (range 27-93); 49% Male; 61% performance score (PS) 0; primary site: 80% skin, 15% UKN, 4% mucosal; 49% BRAF V600mut; 76% AJCC stage IV-M1c; 29% brain metastases; 82% pretreated; 48% CRP >ULN; 33% LDH >ULN; 16% absolute lymphocyte count (ALC)  1.5ULN, CRP > 5xULN or ALC  1.5ULN with a typical “lower PFS plateau" beyond 30 wks. All pts with a baseline ALC  1.5xULN and CRP > 5xULN as independent unfavorable prognostic factors for PFS/OS.

Conclusions

While confirming encouraging survival outcome of advanced melanoma patients treated with PEMBRO outside a clinical trial setting, significant correlations were found between baseline PS, ALC, LDH, CRP and survival.

Clinical trial identification

NCT02673970

Legal entity responsible for the study

UZ Brussel

Funding

UZ Brussel, NKI AVL

Disclosure

J.V. van Thienen: advisory role Bristol-Myers-Squibb and MSD. J.B.A.G. Haanen: advisory role: MSD, Pfizer, Bristol-Myers-Squibb, Novartis, Neon Therapeutics and Roche/Genentech. Research grant: MSD, BMS, GSK. C. Blank: advisory role: MSD, Pfizer, Bristol-Myers-Squibb, Novartis, GSK, Roche/Genentech, Lilly. Research grant: Novartis. B. Neyns: Personal compensation: Roche, Bristol-Myers Squibb, Merck Sharp & Dohme, Novartis, AstraZeneca, CryoStorage for public speaking, consultancy and participation in advisory board meetings. All other authors have declared no conflicts of interest.