# First-in-Human Abdominal Aortic Aneurysms Trial with Tricaprin (F-HAAAT): Study Design and Protocol

## TL;DR

This study tests if tricaprin, a type of dietary fat, is safe and effective in slowing abdominal aortic aneurysm growth in humans.

## Contribution

The first-in-human clinical trial to evaluate tricaprin's safety and potential to reverse aneurysm progression in patients with small AAAs.

## Key findings

- The trial will assess safety through adverse event monitoring and cardiovascular outcomes.
- Efficacy will be evaluated using AAA diameter, volume, Agatston score, and CT wall characteristics.
- Results may reveal noninvasive methods to analyze aneurysm pathology and reverse remodeling.

## Abstract

Approximately 2%-12% of individuals aged > 65 years worldwide are estimated to have an abdominal aortic aneurysm (AAA), with a mortality rate exceeding 60% in rupture cases. The sole preventive intervention against rupture is timely surgery, which requires substantial medical resources, including postoperative complication management. Although numerous randomized clinical trials have been performed, no oral medication effectively treats AAA. Tricaprin, a medium-chain triglyceride with 3 capric acids, is used in dietary therapy for metabolic and neurological disorders. Our group recently reported that tricaprin, unlike other medium-chain triglycerides, showed reverse remodelliing of AAA in a rat model. Determining whether this basic finding could be translated to clinical practice is important. The First-in-Human Abdominal Aortic Aneurysms trial with Tricaprin (F-HAAAT) proposes the first-in-human AAA trial to confirm the safety of tricaprin use in patients with small AAA, exploring novel assessment methods to evaluate treatment efficacy. This single-centre, open-label, single-arm study will include 10 patients (aged 50–85 years) with small AAA (30–45 mm in diameter) receiving daily oral tricaprin (1.5–3.0 g/d) for 52 weeks. Primary endpoints include safety evaluation of tricaprin determined by monitoring all adverse events, particularly major adverse cardiovascular events, AAA-related adverse events, and other unpredictable events. Secondary endpoints include parameters to validate tricaprin efficacy by measuring AAA diameter, volume, and Agatston score, and analyzing computed tomography values of the aortic aneurysmal wall. Outcomes of the trial may provide insights into noninvasive methods for indirectly analyzing AAA pathologic characteristics and revealing aneurysmal reverse remodelliing (jRCTs051240036, Japan Registry of Clinical Trials).