A phase IB/II randomized study of mFOLFIRINOX (mFFOX) + pegylated recombinant human hyaluronidase (PEGPH20) versus mFFOX alone in patients with good performance status metastatic pancreatic adenocarcinoma (mPC): SWOG S1313 (NCT #01959139).

208Background: PEGPH20 degrades hyaluronan (HA), a major component of the stroma, increases delivery of gemcitabine and prolongs survival in preclinical models. We evaluated the activity of PEGPH20 in combination with mFFOX in mPC , unselected for tumor HA. Methods: Pertinent eligibility: untreated mPC, PS of 0-1 and adequate organ function. Standard FFOX was modified to add prophylactic growth factor support and omit bolus 5FU. Due to increased thromboembolic (TE) events with PEGPH20, an amendment instituted LMWH prophylaxis in the PEGPH20 arm only. Following a dose finding cohort of mFFOX + PEGPH20, the Phase II study randomized patients (1:1) to the combination arm or mFFOX alone (n = 138). The primary endpoint was overall survival (OS), with a null median OS of 10 mo and an alternative of 15 mo (1-sided type 1 error 0.1, 80% power). Results: PEGPH20 at 3 mcg/kg, q2 weeks was more tolerable than twice weekly dosing. The randomized phase II study began May 2015. The planned interim futility analysis whe...