ADAPTABLE

Full Title: Aspirin Dosing: A Patient-Centric Trial Assessing Benefits and Long-term Effectiveness
PI: Matthew Roe, MD, MSH
PI Institution: Duke University
OneFlorida Site PI: David Anderson, M.D.
Site PI Institution: University of Florida
Citizen Scientist: William Larson
Citizen Scientist: Nadine Zemon
Study Staff: Brittney Roth

Funding Agency: PCORI

Abstract: Aspirin is a mainstay therapy for patients with atherosclerotic cardiovascular
disease (ASCVD). Aspirin reduces adverse outcomes such as myocardial infarction and stroke
in patients with previous cardiovascular (CV) events and/or atherosclerosis. However, despite
dozens of clinical trials, the optimal dose of aspirin that is most effective in reducing ischemic
events, balanced by the potential for adverse events (e.g. bleeding) has not been determined in
direct comparative-effectiveness trials.

The ADAPTABLE study compares the effectiveness of two, once-daily doses of aspirin (81 mg
versus 325 mg) in a secondary-prevention trial of patients with ASCVD. The trial uses a novel
format that repurposes the use of EHR data that have been standardized per a common format.
The trial uses a web-based communication system among trial investigators and enrolled
patients, with support of health systems interested in optimal patient care.

Specific Aims: The primary aim is to compare adverse outcomes between high-risk patients
with a history of MI or documented atherosclerotic cardiovascular disease assigned to either
low or high dose aspirin. Adverse outcomes are defined as the first occurrence among all-cause
mortality, hospitalization for nonfatal MI, or hospitalization for nonfatal stroke.

The secondary aim is to compare the effects of these aspirin doses in selected, prospectively
defined, subgroups (ie. sex, age, race and chronic conditions).

The third aim is to develop, refine, and evaluate the infrastructure for PCORnet to conduct
multiple comparative-effectiveness trials in the future.

Design: Prospective, Randomized, Open label intervention trial with Blinded Evaluation (PROBE
design) of adverse outcomes the will recruit 20,000 participants over 2 years and follow them
for 2.5 years.