: Doripenem DRPM is a relatively new drug belonging to the carbapenem antibiotic group. We hypothesized that the pharmacological characteristics of DRPM could make it useful in the treatment of severe acute pancreatitis SAP . We investigated the usefulness of continuous regional arterial infusion CRAI with DRPM and protease inhibitors for SAP. Two hundred and forty-two patients with SAP were admitted to Showa University Hospital between November 2002 and June 2013. Of these, 53 patients were treated with CRAI with carbapenem antibiotics and nafamostat mesilate NM , a serine protease inhibitor, via the celiac and superior mesenteric arteries. Clinical outcomes were evaluated retrospectively in 34 patients treated with DRPM and 19 patients undergoing non-DRPM therapy meropenem n 11, imipenem n 6 ; biapenem n 2 . The median time to commencement of oral intake was significantly shorter in the DRPM than non-DRPM group 9 vs 14 hospital days, respectively ; P 0.01 . In addition, the rate of walled-off necrosis in the DRPM group tended to be lower than in the non-DRPM group 37.5 vs 64.7 , respectively, P 0.069 . The results of the present study suggest that CRAI with DRPM and NM for SAP could have equivalent therapeutic effects to CRAI with other carbapenem antibiotics and NM.