Tubes of PVA with or without 30µg GFPGER/g PVA were tested in an ex vivo shunt model. Platelet accumulation was quantified over 60min exposure to whole blood (n=2 for collagen-ePTFE and N=5–6 for other groups). (A) In the absence of antiplatelet drugs, ePTFE devices accumulated significantly more platelets than GFPGER devices (LME ANOVA F2, 11=12.755 p=0.001, post hoc: ePTFE vs. plain PVA, p=1.0, ePTFE vs. GFPGER p=0.0035, plain PVA vs. GFPGER p=0.0834). (B) Under ASA monotherapy, ePTFE devices accumulated significantly more platelets than either PVA device. (LME ANOVA F2,12=13.86 p=8×10−4, post hoc: ePTFE vs. plain PVA p=0.0008, ePTFE vs. GFPGER p=0.0013, plain PVA vs. GFPGER p=1.0). (C) Under DAPT, plain PVA devices accumulated significantly fewer platelets than ePTFE devices (RMA F2,11=3.24 p=0.079, post hoc: ePTFE vs. plain PVA p=0.0310, ePTFE vs. GFPGER p=0.261, plain PVA vs. GFPGER p=0.681).