Clinical trial NCT02475837: Vorapaxar Study for Maturation of AV Fistulae for Hemodialysis Access
Official title: A Double-blind, Randomized, Placebo Controlled Pilot Trial to Evaluate the Safety and Efficacy of Vorapaxar in Maturation of Arteriovenous Fistulae for Hemodialysis Access
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
Conditions: AV Fistula
Lead sponsor: Stanford University
Sponsor class: OTHER
Collaborators: name: Merck Sharp & Dohme LLC
First posted: 2015-06-19
Enrollment: 17
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: 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).

Detailed description: Objectives:

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).

Participation in this study will not affect standard care of patients with AV fistulae receiving hemodialysis. The only additional treatment is administration of the study drug or placebo and additional monitoring, including one additional ultrasound, for 6 months.

Eligibility criteria: Inclusion Criteria:

1. Age \>18
2. Receiving or planning to receive maintenance hemodialysis
3. Ability to sign informed consent
4. 3 mm venous diameter within recipient vein

Exclusion Criteria:

1. History of stroke, transient ischemic attack or intracranial hemorrhage
2. History of or high level of suspicion for, severe arterial insufficiency of the hand
3. Indication or ongoing therapy with other antiplatelet agents, other than aspirin 81 mg daily
4. Indication or ongoing therapy with anticoagulants, including warfarin, low molecular weight heparin, factor Xa inhibitors or direct thrombin and other inhibitors.

Primary outcomes:
measure: Time to AV Fistula Functional Maturation
timeFrame: up to 238 days
Secondary outcomes:
measure: Count of Participants With AV Fistula Use
timeFrame: up to 238 days
measure: Count Participants With AV Fistula Patency
timeFrame: 150-238 days
measure: Count of All Participants With Bleeding Events
timeFrame: up to 238 days
Other outcomes:
Locations:
city: Stanford
country: United States
facility: Stanford Univeristy
state: California
Study officials:
affiliation: Stanford University
name: Matthew W Mell, MD, MS
role: PRINCIPAL_INVESTIGATOR
affiliation: Stanford University
name: Kenneth W Mahaffey, MD
role: PRINCIPAL_INVESTIGATOR
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