VESS15 - Navigating the Challenges for Hemodialysis Access Trials: Insights into Enrollment Barriers and Demographic Trends

Objectives: Despite an increasing number of hemodialysis access (HDA) clinical trials aimed at improving vascular access function and longevity, trial enrollment remains a challenge. This study aims to identify enrollment barriers in contemporary HDA trials and assess whether clinical trial populations reflect the real-world profile of dialysis access patients.

Methods: We performed a retrospective analysis of patients with advanced kidney disease undergoing surgical HDA creation at a quaternary healthcare system, between January 2015 and December 2024. For the clinical trial cohort, we included patients enrolled in six HDA randomized controlled trials. For the real-world cohort, we utilized our institutional Vascular Quality Initiative (VQI) database to capture patients receiving a new HDA. Primary analysis compared the demographic profile (age, sex, race, and ethnicity) of patients enrolled in HDA trials versus those treated in the real-world setting. In secondary analyses, we examined barriers limiting clinical trial enrollment.

Results: A total of 132 patients undergoing HDA creation were enrolled in clinical trials and 1,327 patients were treated in the control real-world practice. Mean age (SD) of patients enrolled in clinical trials was 63 (15) versus 64 (15) years for those treated in real-world practice (p=0.39) (Table I). A numerical trend toward lower number of women were enrolled in HDA clinical trials (38%) compared to real-world practice (46%), although this did not reach statistical significance (p=0.08). Racial minorities were significantly less likely to be enrolled in trials compared to the real-world practice (29% vs. 43%, respectively, p< 0.01). Among clinical trial patients, the most common reasons for screen failure were patient preference (30%) and anatomical exclusion (30%) (Fig 1). Patient preference reasons included those who withdrew consent because of reluctance to receive an investigational device/drug; patients having transportation barriers which prevented follow-up protocol adherence; and surgery date/location falling outside of the protocol requirements. Anatomical exclusion criteria included inadequate vein anatomy, intended access too deep, a 2-stage procedure required, and access configuration not within trial inclusion criteria (most commonly snuff-box fistula).

Conclusions: Compared to real-world dialysis access practice, racial minorities are underrepresented in HDA clinical trials at an academic center. Patient reluctance to receive an investigational product, transportation barriers limiting patient adherence to trial follow-up requirements, and strict anatomical inclusion criteria reflect important challenges in HDA trial enrollment. Further understanding this landscape may inform strategies to improve HDA trial design and ensure more inclusive clinical trial participation to reflect real-world practice.