DOTATATE PETMRI AAA Study

Gallium-DOTATATE PET-MR Imaging to Detect Macrophages in Abdominal Aortic Aneurysms

Abdominal Aortic Aneurysm (AAA) screening and an aging population have increased the prevalence of AAA diagnoses. Small AAAs (<5.5cm) are monitored with ultrasound. Large AAAs may rupture and this is usually fatal. Surgery is considered at a crude size threshold of 5.5cm when the annual rupture risk reaches 5%. AAA size is the only predictor of growth and rupture available but growth is non-linear and some small AAAs rupture. Thus, only 1 in 20 patients treated at 5.5cm will have benefited from rupture prevention in the year following surgery, and others may miss out on life-saving surgery. This study will develop an imaging tool PETMRI with radiotracer Ga- DOTATATE with high clinical utility, to improve prediction of aneurysm growth and risk.

Study Overview

• Status: Recruiting
• Conditions: Abdominal Aortic Aneurysm
• Intervention / Treatment: Diagnostic test: Ga-DOTATATE PETMRI scan

Detailed Description

The prevalence of abdominal aortic aneurysm (AAA) in those over 65 years is 4-8% and rising. Currently, AAA size is the only metric to determine risk of growth/rupture; we are unable to image the underlying disease process. Using size alone is problematic. For small AAAs there is no consensus between surgical societies on appropriate surveillance intervals. AAA growth is non-linear and thus some small AAAs may rupture between screening intervals.

Macrophage mediated inflammation leads to weakening of the aortic wall. Our own laboratory work indicates macrophages correlate with AAA severity in mice. In humans, activated macrophages express SomatoSTatin Receptor 2 (SSTR2). For the first time ever, using a radiotracer probe specific for SSTR 2 (gallium-dotatate), we will detect activated macrophages in AAAs using Positron Emission Tomography- Magnetic Resonance Imaging (PET-MRI). Patients attending the University Health Network (UHN) Vascular clinic undergoing ultrasound surveillance of small AAAs of differing sizes will be imaged with Ga-Dotatate PET-MRI. We will correlate aneurysm size and anatomical information with in-vivo imaging of aortic macrophages detected with Ga-Dotatate, to determine the risk of aneurysm growth.

• Study Type: Interventional
• Enrollment (Anticipated): 55
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Iris Zhong; Phone Number: 4816 416-946-4501; Email: iris.zhong@uhn.ca

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G 2N2
      • Recruiting
      • University Health Network
      • Contact: Iris Zhong; Phone Number: 4816 416-946-4501; Email: iris.zhong@uhn.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Diagnosis of asymptomatic abdominal aortic aneurysm AAA >3cm in maximum diameter;
2. Minimum 2 years prior ultrasound or CT imaging of their AAA;
3. No prior treatment for AAA;
4. Age >50 years;
5. No contraindications to PET/MRI, such as claustrophobia;

Exclusion Criteria:

1. Pregnant females. All women of child-bearing potential must receive a negative urine pregnancy test prior to administration of 68Ga-DOTATATE;
2. Allergy and/or hypersensitivity to MRI contrast agents (gadolinium) or components of 68Ga-DOTATATE drug product (as listed in IB);
3. Presence of pacemaker or implanted cardioverter defibrillator (ICD);
4. History of alcohol or substance abuse.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Ga-DOTATATE PET/MRI scan; Patients with abdominal aortic aneurysm will undergo Ga-DOTATATE PET/MRI scan	Diagnostic test: Ga-DOTATATE PETMRI scan; Patients with AAA with minimum 2 years surveillance will have one time Ga-DOTATATE PETMRI scan

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
68-Ga DOTATATE uptake	Measuring AAA patient's 68-Ga DOTATATE uptake using PET/MRI as a marker of macrophage accumulation	within 6 months after obtaining consent

Collaborators and Investigators

• Sponsor: University Health Network, Toronto
• Investigators: Principal Investigator: Patrick Veit-Haibach, University Health Network, Toronto

Study record dates

Study Major Dates

• Study Start (Actual): February 15, 2021
• Primary Completion (Anticipated): December 31, 2023
• Study Completion (Anticipated): December 31, 2023

Study Registration Dates

• First Submitted: March 10, 2021
• First Submitted That Met QC Criteria: March 19, 2021
• First Posted (Actual): March 23, 2021

Study Record Updates

• Last Update Posted (Actual): March 23, 2021
• Last Update Submitted That Met QC Criteria: March 19, 2021
• Last Verified: March 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Aortic Diseases; Aneurysm; Aortic Aneurysm; Aortic Aneurysm, Abdominal
• Other Study ID Numbers: 20-5802

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No