Vorapaxar Study for Maturation of AV Fistulae for Hemodialysis Access

The Objectives of this study are: 1. To determine if vorapaxar safely improves arteriovenous (AV) fistula functional maturation when administered during the maturation process compared with placebo. 2. To determine if vorapaxar safely improves AV fistula patency, allowing for secondary procedures to aid in fistula maturation compared with placebo. 3. To determine if vorapaxar safely facilitates successful cannulation of AV fistulas for hemodialysis compared with placebo. This is a randomized placebo-controlled double-blind pilot trial. Study procedures will be conducted at Stanford University Medical Center, and standard-of-care (SOC) procedures will be conducted at Stanford and it\'s affiliated hospitals (Veteran\'s Affairs Palo Alto Health Care System and the Stanford Vascular Surgery Clinic at Valley Medical Center). The investigators expect to enroll 128 patients. Patients will be assigned to treatment groups with a 1:1 randomization in blocks of 4 at the conclusion of the AV fistula creation. Patients will be stratified based on fistula location (lower arm versus upper arm).