Today’s cyclodextrin is a Freshly Approved HPBCD-Enabled Radioactive Drug Formulation.
GE HealthCare announced that the U.S. Food and Drug Administration (FDA) has granted approval of Flyrcado™ (flurpiridaz F 18) injection, a first of its kind positron emission tomography myocardial perfusion imaging (PET MPI) agent, for the detection of coronary artery disease (CAD).
FLYRCADO is a sterile, preservative-free, non-pyrogenic, clear, colorless to yellow radioactive solution. Each mL contains 190 MBq to 2,050 MBq (5 mCi to 55 mCi) of flurpiridaz F 18 at end of synthesis, up to 2.3 mcg flurpiridaz, and the following inactive ingredients: 45 mg hydroxypropyl-β-cyclodextrin (as a solubilizer and co-radiostabilizer), 35 mg L-(+)-ascorbic acid (as a radiostabilizer), 8.2 mg sodium hydroxide, and 55.2 mg anhydrous ethanol, in water for injection. The pH of the solution is between 5.5 and 8.
Deeper insight into the surprising radiostabilizer function is found in the corresponding patent application (WO2021078814A1 – Use of cyclodextrins as a radiostabilizer – Google Patents), however, the mechanism is undisclosed. My guess is that HPBCD prevents the loss of activity by hindering the adsorption of the radiolabeled drug onto the container wall.
