**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Eric Webster
University of Tennessee Graduate School of Medicine
Knoxville, TN

**Main Body of the Abstract**
Background: Nuclear imaging is a promising method for the early detection of systemic amyloidosis. Peptide p5+14 is capable of binding all types of amyloid and can accept many radionuclides for PET or SPECT imaging. Peptide p5+14 has been successfully radiolabeled with iodine-124 and technetium-99m and evaluated clinically. Fluorine-18 is the most widely used PET radionuclide. Here we describe synthesis of a fluorine-18-labeled p5+14 and initial characterization of the reagent.
Methods: The silicon-fluoride-acceptor isotopic exchange method was used to radiolabel peptide p5+14 with fluorine-18. After drying, F-18 (<51 mCi) was dissolved in DMSO before addition of peptide precursor. After purification of the product, radiochemical purity and stability were measured. Binding to amyloid extracts was assessed, and the biodistribution of 18F-p5+14 was evaluated in mice using PET/CT imaging and biodistribution.
Results: The synthesis yield was 45±4%, and the product was radiochemically stable for >5 hours.  The binding of 18F-p5+14 to synthetic rVl6WIL amyloid-like fibrils was 96.2% with 87.2% binding to human AL amyloid extracts. In AA mice, accumulation of 18F-peptide was observed in the liver and spleen using PET imaging at 1 h post injection. The peptide was eliminated by hepatobiliary clearance with a prominent gall bladder seen in the images. No free F-18 was observed in bone.
Conclusion: Efficient radiofluorination of p5+14 can be achieved using isotopic exchange chemistry. The bioactivity of 18F-p5+14 mimics that of other pan amyloid probes labeled with I-124 or Tc-99m and offers another alternative for the specific detection of amyloid by PET/CT imaging.



**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Eric Webster
University of Tennessee Graduate School of Medicine
Knoxville, TN

**Main Body of the Abstract**
**Background:** Nuclear imaging is a promising method for the early detection of systemic amyloidosis. Peptide p5+14 is capable of binding all types of amyloid and can accept many radionuclides for PET or SPECT imaging. Peptide p5+14 has been successfully radiolabeled with iodine-124 and technetium-99m and evaluated clinically. Fluorine-18 is the most widely used PET radionuclide. Here we describe synthesis of a fluorine-18-labeled p5+14 and initial characterization of the reagent.
**Methods:** The silicon-fluoride-acceptor isotopic exchange method was used to radiolabel peptide p5+14 with fluorine-18. After drying, F-18 (<51 mCi) was dissolved in DMSO before addition of peptide precursor. After purification of the product, radiochemical purity and stability were measured. Binding to amyloid extracts was assessed, and the biodistribution of ^18^F-p5+14 was evaluated in mice using PET/CT imaging and biodistribution.
**Results:** The synthesis yield was 45±4%, and the product was radiochemically stable for >5 hours.  The binding of ^18^F-p5+14 to synthetic rVl6WIL amyloid-like fibrils was 96.2% with 87.2% binding to human AL amyloid extracts. In AA mice, accumulation of ^18^F-peptide was observed in the liver and spleen using PET imaging at 1 h post injection. The peptide was eliminated by hepatobiliary clearance with a prominent gall bladder seen in the images. No free F-18 was observed in bone.
**Conclusion:** Efficient radiofluorination of p5+14 can be achieved using isotopic exchange chemistry. The bioactivity of ^18^F-p5+14 mimics that of other pan amyloid probes labeled with I-124 or Tc-99m and offers another alternative for the specific detection of amyloid by PET/CT imaging.



Early Development and Pre-Clinical Evaluation of a Fluorine-18 Labeled Peptide, p5+14, for the Detection of Amyloid Cardiomyopathy by PET/CT Imaging PB114 (#298)

We invite you to attend the XIX International Symposium on Amyloidosis to be held in Rochester, MN.

This symposium is organized as a hybrid meeting (with the focus on in-person) held from Sunday, May 26 through Thursday, May 30, 2024.

Together with the ISA Board and members of Mayo Clinic, a very attractive scientific hybrid program is being planned. The program will cover a variety of types of systemic amyloidosis: ATTR (hereditary and wild-type), AL (light-chain), AA and less frequent forms. There will be key lectures, specific symposia including those company sponsored, oral presentations and poster sessions of accepted abstracts.

COURSE DESCRIPTION
This program will provide a comprehensive review of state-of-the-art education in systemic amyloidosis: basic science, pathophysiology, diagnosis, current and emerging treatments. Scientific presentations will include competitive oral and poster abstracts. The rapid evolution of scientific discovery and expanding treatment options has created tremendous interest in the field and this meeting will fill and important gap in educating scientists and clinicians.