Dosimetry, biodistribution, and safety of flurpiridaz F 18 in healthy subjects undergoing rest and exercise or pharmacological stress PET myocardial perfusion imaging

Abstract

The objectives of this study were to evaluate radiation dosimetry, biodistribution, human safety, and tolerability of ¹⁸F-labeled flurpiridaz (Flurpiridaz) in normal subjects undergoing rest and separate-day exercise or adenosine pharmacological stress PET imaging.

Methods: 12 normal subjects were injected with 58.5 to 121 MBq (1.58 to 3.27 mCi) of Flurpiridaz intravenously at rest on Day 1 and 57 to 171 MBq (1.54 to 4.61 mCi) during stress on Day 2. Sequential whole-body imaging was performed for 5 hours. Blood samples were collected for up to 8 hours.

Results: The heart wall received the largest mean absorbed dose with both exercise and adenosine stresses. The mean effective dose was 0.054 rem/mCi (0.015 mSv/MBq) with exercise and 0.069 rem/mCi (0.019 mSv/MBq) with adenosine pharmacological stress. The maximum dose that may be administered without exceeding 1 rem (10 mSv) effective dose was 19 mCi (685 MBq) for exercise and 15 mCi (539 MBq) for adenosine pharmacological stress. There were no drug-related adverse events, and the tracer was well tolerated in all subjects.

Conclusion: Based on radiation dosimetry, biodistribution, and safety observations, ¹⁸F-labeled flurpiridaz is found suitable for clinical PET myocardial perfusion imaging in conjunction with either exercise or pharmacological stress testing.

Keywords: Flurpiridaz; dosimetry and biodistribution; exercise cardiac PET imaging; myocardial perfusion PET imaging; safety.