An observational study of patients with advanced melanoma receiving pembrolizumab in a real-world U.S. community oncology practice.

Abstract

Listen

Translate article

e21015 Background: PD-1 monoclonal antibodies are promising immunotherapies approved for treatment of patients (pts) with advanced melanoma. As the first US FDA approved PD-1 antibody, pembrolizumab (pembro) has demonstrated efficacy and safety in clinical trial settings. However, patterns of real world utilization and pt outcomes associated with pembro are limited. Methods: Adult pts with advanced melanoma who initiated pembro between 9/1/ 2014-3/31/2016 were identified retrospectively fromelectronic health records (EHR) of McKesson Specialty Health and followed through 9/ 30/2016. Pts in clinical trials were excluded. Demographic, disease, treatment characteristics and reasons for treatment discontinuation of pembro were abstracted from structured data elements of the EHR with further supplementation of unstructured data within the patient chart (progress notes, radiology scan reports). Overall survival (OS) and physician-reported progression free survival (PFS) from pembro initiation were analyzed using Kaplan Meier analysis. Results: 182 pts, with a median follow-up of 9.9 mos (range = 0.0-25.0), were included. Median age at pembro initiation was 66.0 yrs; 30.8% had an elevated lactate dehydrogenase (LDH); 23.6% had brain metastases and 65.4% had an ECOG performance status of 0 or 1. The most common reason for pembro discontinuation was progression (45.5%) followed by treatment-related toxicity (24.4%). In the overall population, median PFS from pembro initiation was 4.2 mos (95% CI = 3.2-5.3). Median OS was 19.4 mos (14.0-NR) with 12 and 24-month survival probabilities of 61.4% (95% CI = 53.4-68.5) and 43.9% (95% CI = 31.1-55.9). In multivariable analyses, characteristics predictive of worse survival included receipt of pembro at a later line of therapy (HR = 3.36, p = 0.0013 for 3L+), presence of brain metastases (HR = 2.67, p = 0.0007) and elevated LDH (HR = 4.10, p < 0.0001). Conclusions: The study results are consistent with those from pembro clinical trials (KeyNote001) and are in support of the effectiveness of pembro in real world treatment of advanced melanoma. Presence of brain metastases, elevated LDH, and use of pembro 3L+ were associated with worse survival outcome.