Novel PET Radiotracer Studied to Diagnose AAA and Predict Rupture

June 15, 2021—The Society of Nuclear Medicine and Molecular Imaging (SNMMI) announced findings demonstrating that a new positron emission tomography (PET) radiotracer can detect abdominal aortic aneurysms (AAAs) and potentially predict when they will rupture. The study was presented at the SNMMI 2021 annual meeting held virtually June 11-15.

According to SNMMI, the study demonstrated that by targeting a novel biomarker associated with AAA, the radiotracer is effective both in diagnosis and in providing information to assist in the development of AAA treatments.

As noted in the SNMMI press release, the investigators from Washington University School of Medicine in St. Louis, Missouri, identified chemokine receptor type 2 (CCR2) as a potential novel biomarker for AAA evaluation. They developed the novel PET tracer, 64Cu-DOTA-ECL1i, and it has been used to perform first-in-AAA patient imaging.

The investigators found that:

• 64Cu-DOTA-ECL1i PET was confirmed to be safe and effective for imaging CCR2 in AAA patients.
• 64Cu-DOTA-ECL1i was utilized to assess CCR2-targeted treatment in preclinical animal AAA rupture models.

In the models, 64Cu-DOTA-ECL1i imaging was highly suggestive of subsequent AAA rupture. Additionally, in a designated cohort of animals that received a CCR2 inhibitor as a form of therapy, the investigators were able to demonstrate the effective prevention of AAA rupture.

The study by Gyu Seong Heo, PhD, was presented at the SNMMI’s 2021 annual meeting as abstract 133 “Evaluation of CCR2 as a theranostic biomarker for abdominal aortic aneurysm.”

“Right now, clinical diagnosis of AAA relies on anatomic measurements of AAA diameter, which is a poor marker for the prediction of rupture,” commented Dr. Heo in the SNMMI press release. “Thus, there is an unmet clinical need for a novel molecular biomarker to determine the underlying processes that lead to aneurysm expansion and rupture and to serve as a therapeutic target for better management of AAA patients.”

Dr. Heo, who is a postdoctoral researcher at Washington University School of Medicine, continued, “Given the availability of CCR2 inhibitors for human uses, our work holds great potential to assess AAA vulnerability, screen AAA patients for CCR2-targeted treatment, and determine treatment response for optimal outcome.”