e16217 Background: The vast majority of pancreatic ductal adenocarcinoma (PDAC) patients have unresectable disease at diagnosis, with only about 20% presenting with either resectable or borderline resectable tumors and who may receive adjuvant with or without neo-adjuvant treatment with surgery. This study seeks to characterize these treatment patterns in the real-world setting. Methods: This was a retrospective observational study to evaluate adjuvant treatment of PDAC patients, with or without neo-adjuvant treatment in the U.S. Patients with at least two medical claims with a primary diagnosis for PDAC between 2016 to 2019 were identified in the Truven MarketScan administrative claims database. A surgical resection within 3 months of any primary PDAC coded medical encounter was the index event, with patients required to be continuously enrolled for at least 3 months before and 6 months after the surgery. Patient demographics and treatment patterns (chemotherapy, radiotherapy, and chemoradiation) were evaluated over the pre-index (3 months) and post-index (3 and 6 months) observation windows. Neo-adjuvant and adjuvant treatment patterns were reported for the overall population and also stratified by age and sex. Results: 737 patients met the selection criteria with a majority (n=520, 71%) being <65 years old and 53% females (n=387). 65% (n=478) of patients received adjuvant chemotherapy during the 6-month post-index compared with 28% (n=207) receiving neo-adjuvant treatment. In the neo-adjuvant setting, patients were likely to receive leucovorin+fluorouracil+irinotecan+oxaliplatin (FOLFIRINOX; 43%, n=88) followed by gemcitabine+pacitaxel (18%, n=37), across all patients, as well as stratified by age or sex. Among patients that received adjuvant but did not receive neo-adjuvant treatment, patients were likely to receive gemcitabine monotherapy (35%, n=112) followed by gemcitabine+capecitabine (GEMCAP; 23%, n=72). Among adjuvant patients that had received neo-adjuvant treatment, the most common chemotherapy regimens were gemcitabine monotherapy (22%, n=35), GEMCAP (18%, n=29) and FOLFIRINOX (16%, n=26). For patients ≥ 65 years old, the most common adjuvant regimen was gemcitabine monotherapy (n=62, 29%) whereas for patients <65, the most common regimens were GEMCAP (25%, n=90) and gemcitabine monotherapy (16%, n=85). Gemcitabine monotherapy (41%; n=118 of 453) was the main adjuvant regimen for patients with index dates of 2016-2017 but for those with index dates of 2018-2019 the most common was FOLFIRINOX (34%; n=64 of 284) followed by GEMCAP (18%; n=35 of 284). Conclusions: The majority (70%) of patients that underwent PDAC resection surgery did not receive neo-adjuvant treatment and about a third of patients did not receive any adjuvant treatment. These results suggest an unmet need in the management of PDAC.
