Real-world use of liposomal irinotecan-based regimens among patients (pts) with metastatic pancreatic adenocarcinoma (mPDAC) in the United States (U.S.).

Abstract

e16740 Background: The goals of randomized control trials (RCTs) are to make causal inferences and precise treatment comparisons, not to describe large heterogeneous pt populations. RWE allows population-based healthcare decision makers to assess and manage therapeutic and economic options for their pts, including those who would and would not have met inclusion/exclusion criteria of a given RCT and are instead managed under usual care, irrespective of clinical trial protocols. In the pivotal phase 3 trial, NAPOLI-1, 117 pts were treated with liposomal irinotecan + 5-fluorouracil/folinic acid, median age 63 years; 66% were treated first- (1L) or second line (2L), and 91% had performance score ECOG 0 or 1. Pts in the trial had overall survival (OS) of 6.2 months (mos), time to treatment failure (TTF) 2.3 mos, and 27% experienced grades 3-4 neutropenia. The present study describes the patient characteristics and outcomes of pts with mPDAC treated with liposomal irinotecan in the US. Methods: This retrospective observational study used data from Flatiron Health EHR-derived de-identified database from over 280 cancer clinics. Patient characteristics, OS, TTF, and rates of neutropenia during treatment (tx) were assessed in adult pts diagnosed with mPDAC who received liposomal irinotecan based tx between November 1, 2015 and October 31, 2019. Results: 600 pts with mPDAC treated with a liposomal irinotecan based regimen were identified. Of these, 56% were initially diagnosed with stage IV disease, 53% were male, 21% had undergone a previous Whipple procedure, and 61% initiated liposomal irinotecan in the 1L or 2L metastatic setting. Median age at tx initiation was 68 (IQR: 62 – 75) years. 92% of pts were treated in the community setting. Among pts with available ECOG (n = 440), 77.5% were score 0-1. Grade 3/4 neutropenia was observed in 11% (n = 66). Overall, median OS was 5.0 mos [95%CI: 4.2–5.6]. mOS among pts treated in 1L (n = 88), 2L (n = 280), and third line plus (3L+, n = 232) were 6.9 mos [5.3–9.2], 5.4 mos [4.6–6.4], and 4.0 mos [3.4–4.5], respectively. Overall, median TTF was 1.9 mos [1.6–2.1]. TTF by line was 3.5 mos [2.3–4.8] in 1L, 2.1 mos [1.7–2.8] in 2L, and 1.4 mos [1.2–1.6] in 3L. Conclusions: This real-world cohort of pts with mPDAC were older, had worse performance status, and had more prior lines compared to the pivotal trial for liposomal irinotecan. Median OS, TTF, and neutropenia were similar to those previously reported. As expected, pts receiving liposomal irinotecan in earlier lines had higher median OS and TTF.