Real-world evidence (RWE) to show improved time to progression among resected pancreatic cancer (RPC) patients receiving adjuvant chemotherapy (adjch).

Abstract

242 Background: Two recent clinical trials (IMPRESS and APACT) suggest the overall survival (OS) of patients with resected pancreatic cancer (RPC) is far longer than previously believed. Improvements in patient selection, intra/post-operative surgical care adjch are suggested as explanations for the improved OS. RWE of time to progression (TTP) from surgery were calculated to assess if the results of these trials are generalizable. Methods: RPC patients (ICD-9=157.x, excluding 157.4; CPT=48140, 48146, 48150, 48152-5) diagnosed between 03/2012-06/2015 were selected from the Inovalon More2 administrative claims database. Adjch was defined as initiating chemotherapy within 90 days of surgery. TTP was the time from surgery until the first claim for metastatic disease (ICD-9 =196.0-.3, .5-.6, 197.0-.8, 198.0-.8) using the Kaplan-Meier method. Patients without a metastatic diagnosis during their follow-up were censored at 12 months to adjust for underreporting of metastatic disease codes in claims. Results: 1,014 RPC patients selected. Mean follow-up time was 12.9 months (SD = 10.8). Mean age at diagnosis was 62.7 years (SD = 13.0) and 39.7% (n=403) had commercial insurance, 40.9% (n=415) Medicare and 18.5% (n=188) Medicaid. Of all RPC patients, 54.4% (n=552) received any chemotherapy of which 59.8% (n=330) was adjch; 37.4% (n=379) were diagnosed with metastatic disease at the time of or following resection. The rate of progression events was 40.5% (n=277) without adjch and 30.9% (n=102) with adjch (p<0.01). Among all resected patients, median TTP was 15.7 months (95% CI: 13.8-26.0) with 93.7% (n=355) of progression events by 12 months. Median TTP was 20.4 months (95% CI: 15.5-NR) in patients receiving adjch vs 17.7 months (95% CI: 17.7-31.5) without adjch (p=<0.0001). Conclusions: This analysis demonstrated a 2.7 month longer TTP for patients who received adjch compared to those who did not (p<0.0001). The median TTP in both adjch and non-adjch groups was longer than the observed in the ESPAC-1 trial for adjch patients TTP (15.3 months) and OS (20.1 months). These data support a new baseline for efficacy in adjch trials and are in line with more recent RCT estimates.