R33HL146835
Project Grant
Overview
Grant Description
The Limiting AAA with Metformin (LIMIT) trial - project summary
Abdominal Aortic Aneurysm (AAA) disease is a common cause of premature death in adult Americans. To date, no medical (e.g., non-surgical) therapies have proven effective at limiting AAA disease progression, or reducing the risk of AAA rupture or aneurysm-related sudden death.
The recognition that diabetic individuals are less likely to develop AAAs and when present in diabetics, AAAs enlarge less rapidly and rupture less frequently, introduces new possibilities for medical AAA disease management. Recent retrospective studies suggest that metformin, the world's most commonly prescribed oral hypoglycemic agent, may be associated with reduced rates of AAA enlargement. To date, however, the ability of metformin to suppress AAA disease has not been evaluated in a scientifically rigorous, prospective fashion.
Building off existing observational evidence and novel preliminary data, generated to support this proposal, it is our fundamental hypothesis that metformin therapy will safely suppress AAA disease progression in non-diabetic patients. To test this hypothesis, two specific aims are proposed.
The first aim will evaluate the tolerability and safety of metformin in non-diabetic patients with AAA disease. Tolerance will be assessed by the serial administration of quality of life surveys and tracking participant compliance and retention. Safety will be assessed by semi-annual examinations, review of the source medical record, supplementary hematologic and metabolic panel surveys as needed.
The second aim will test the ability of metformin XR (extended release) to reduce the average annual rate of enlargement of existing small to intermediate size AAAs by = 30% compared to placebo. For this aim, 480 participants will be randomized 1:1 to metformin or placebo. The primary endpoint will be the increase in mean maximal orthogonal AAA diameter through 24 months, as determined by computed tomographic aortography (CTA).
Successful completion of these aims will advance the understanding of AAA disease as well as the translational utility of metformin therapy to treat cardiovascular diseases in non-diabetic patients. These aims specifically address the NIH strategic vision goals of 1) understanding human biology, 2) reducing human disease, and 3) advancing translational research, as well as objectives of 1) understanding normal biologic function and resilience, 2) investigating newly discovered pathobiological mechanisms, and 3) developing and optimizing novel therapeutic strategies to prevent, treat and cure HLBS diseases.
Abdominal Aortic Aneurysm (AAA) disease is a common cause of premature death in adult Americans. To date, no medical (e.g., non-surgical) therapies have proven effective at limiting AAA disease progression, or reducing the risk of AAA rupture or aneurysm-related sudden death.
The recognition that diabetic individuals are less likely to develop AAAs and when present in diabetics, AAAs enlarge less rapidly and rupture less frequently, introduces new possibilities for medical AAA disease management. Recent retrospective studies suggest that metformin, the world's most commonly prescribed oral hypoglycemic agent, may be associated with reduced rates of AAA enlargement. To date, however, the ability of metformin to suppress AAA disease has not been evaluated in a scientifically rigorous, prospective fashion.
Building off existing observational evidence and novel preliminary data, generated to support this proposal, it is our fundamental hypothesis that metformin therapy will safely suppress AAA disease progression in non-diabetic patients. To test this hypothesis, two specific aims are proposed.
The first aim will evaluate the tolerability and safety of metformin in non-diabetic patients with AAA disease. Tolerance will be assessed by the serial administration of quality of life surveys and tracking participant compliance and retention. Safety will be assessed by semi-annual examinations, review of the source medical record, supplementary hematologic and metabolic panel surveys as needed.
The second aim will test the ability of metformin XR (extended release) to reduce the average annual rate of enlargement of existing small to intermediate size AAAs by = 30% compared to placebo. For this aim, 480 participants will be randomized 1:1 to metformin or placebo. The primary endpoint will be the increase in mean maximal orthogonal AAA diameter through 24 months, as determined by computed tomographic aortography (CTA).
Successful completion of these aims will advance the understanding of AAA disease as well as the translational utility of metformin therapy to treat cardiovascular diseases in non-diabetic patients. These aims specifically address the NIH strategic vision goals of 1) understanding human biology, 2) reducing human disease, and 3) advancing translational research, as well as objectives of 1) understanding normal biologic function and resilience, 2) investigating newly discovered pathobiological mechanisms, and 3) developing and optimizing novel therapeutic strategies to prevent, treat and cure HLBS diseases.
Funding Goals
TO FOSTER HEART AND VASCULAR RESEARCH IN THE BASIC, TRANSLATIONAL, CLINICAL AND POPULATION SCIENCES, AND TO FOSTER TRAINING TO BUILD TALENTED YOUNG INVESTIGATORS IN THESE AREAS, FUNDED THROUGH COMPETITIVE RESEARCH TRAINING GRANTS. SMALL BUSINESS INNOVATION RESEARCH (SBIR) PROGRAM: TO STIMULATE TECHNOLOGICAL INNOVATION, USE SMALL BUSINESS TO MEET FEDERAL RESEARCH AND DEVELOPMENT NEEDS, FOSTER AND ENCOURAGE PARTICIPATION IN INNOVATION AND ENTREPRENEURSHIP BY SOCIALLY AND ECONOMICALLY DISADVANTAGED PERSONS, AND INCREASE PRIVATE-SECTOR COMMERCIALIZATION OF INNOVATIONS DERIVED FROM FEDERAL RESEARCH AND DEVELOPMENT FUNDING. SMALL BUSINESS TECHNOLOGY TRANSFER (STTR) PROGRAM: TO STIMULATE TECHNOLOGICAL INNOVATION, FOSTER TECHNOLOGY TRANSFER THROUGH COOPERATIVE R&D BETWEEN SMALL BUSINESSES AND RESEARCH INSTITUTIONS, AND INCREASE PRIVATE SECTOR COMMERCIALIZATION OF INNOVATIONS DERIVED FROM FEDERAL R&D.
Grant Program (CFDA)
Awarding / Funding Agency
Place of Performance
Stanford,
California
94305
United States
Geographic Scope
Single Zip Code
Related Opportunity
Analysis Notes
Amendment Since initial award the total obligations have increased 274% from $1,729,290 to $6,470,422.
The Leland Stanford Junior University was awarded
Metformin for Limiting AAA Disease Progression
Project Grant R33HL146835
worth $6,470,422
from National Heart Lung and Blood Institute in September 2020 with work to be completed primarily in Stanford California United States.
The grant
has a duration of 5 years 9 months and
was awarded through assistance program 93.837 Cardiovascular Diseases Research.
The Project Grant was awarded through grant opportunity Single-Site Investigator-Initiated Clinical Trials (R61/R33 Clinical Trial Required).
Status
(Ongoing)
Last Modified 9/5/25
Period of Performance
9/21/20
Start Date
6/30/26
End Date
Funding Split
$6.5M
Federal Obligation
$0.0
Non-Federal Obligation
$6.5M
Total Obligated
Activity Timeline
Subgrant Awards
Disclosed subgrants for R33HL146835
Transaction History
Modifications to R33HL146835
Additional Detail
Award ID FAIN
R33HL146835
SAI Number
R33HL146835-2076203534
Award ID URI
SAI UNAVAILABLE
Awardee Classifications
Public/State Controlled Institution Of Higher Education
Awarding Office
75NH00 NIH National Heart, Lung, and Blood Institute
Funding Office
75NH00 NIH National Heart, Lung, and Blood Institute
Awardee UEI
HJD6G4D6TJY5
Awardee CAGE
1KN27
Performance District
CA-16
Senators
Dianne Feinstein
Alejandro Padilla
Alejandro Padilla
Budget Funding
| Federal Account | Budget Subfunction | Object Class | Total | Percentage |
|---|---|---|---|---|
| National Heart, Lung, and Blood Institute, National Institutes of Health, Health and Human Services (075-0872) | Health research and training | Grants, subsidies, and contributions (41.0) | $3,572,088 | 100% |
Modified: 9/5/25