Overview
11 DESCRIPTION 11.1 Chemical Characteristics Fluorodopa F 18 Injection is a radioactive diagnostic agent used in PET imaging. The active ingredient 6-[ 18 F] Fluoro-L-3, 4-dihydroxyphenylalanine has the molecular formula of C 9 H 10 FNO 4 with a molecular weight of 214.18, and has the following chemical structure: Fluorodopa F 18 Injection is a sterile, pyrogen-free, clear, colorless solution.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action In dopaminergic nerve terminals in the brain, Fluorodopa (FDOPA) F 18 is decarboxylated by amino acid decarboxylase to Fluorodopamine (FDA) F 18 and stored in presynaptic vesicles in the brain. The accumulation of F 18 FDA in the striatum is visually detected in the PET scan. 12.2 Pharmacodynamics Optimal PET imaging is achieved between 75 to 90 minutes after administration of Fluorodopa F 18 Injection based on its pharmacokinetics. The relationship between Fluorodopa F 18 dose and plasma concentration is not fully characterized. 12.3 Pharmacokinetics Distribution Following the intravenous administration, Fluorodopa F 18 is cleared from the blood with a biologic half-life of about 1 to 3 hours.
Indications
- 1 INDICATIONS AND USAGE Fluorodopa F 18 Injection is indicated for use in positron emission tomography (PET) to visualize dopaminergic nerve terminals in the striatum for the evaluation of adult patients with suspected Parkinsonian syndromes (PS). Fluorodopa F 18 PET is an adjunct to other diagnostic evaluations. Fluorodopa F 18 Injection is a radioactive diagnostic agent indicated for use in positron emission tomography (PET) to visualize dopaminergic nerve terminals in the striatum for the evaluation of adult patients with suspected Parkinsonian syndromes (PS).
Common Doses
- 150 mg
Dosage
2 DOSAGE AND ADMINISTRATION • The recommended adult dose is 185 megabecquerels (MBq) [5 millicuries (mCi)] by intravenous injection infused over 1 minute. ( 2.2 ) • Use aseptic techniques and radiation shielding to maintain sterility during all operations involved in the manipulation and administration of Fluorodopa F 18 Injection. ( 2.1 , 2.2 ) • Instruct patients to void immediately before imaging and start imaging at approximately 80 minutes post administration (with a 9 second CT scan for attenuation correction) followed by 3D PET scan from 80 to 100 minutes post administration. ( 2.
Contraindications
- 4 CONTRAINDICATIONS None None
Side Effects
- 6 ADVERSE REACTIONS Injection site pain occurred with administration based on a review of the published literature. ( 6.2 ) To report SUSPECTED ADVERSE REACTIONS, contact The Feinstein Institutes for Medical Research at 516-562-1052 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
Interactions
- 7 DRUG INTERACTIONS Aromatic L-amino acid decarboxylase (AADC) inhibitors Prior to Fluorodopa F 18 Injection administration, use of AADC inhibitors (e.g. carbidopa, benserazide etc.) may increase Fluorodopa F 18 bioavailability to the brain by inhibiting peripheral decarboxylase activity and restricting peripheral Fluorodopa F 18 metabolism [see Dosage and Administration ( 2.3 )] . Dopamine agonists, dopamine reuptake inhibitors, dopamine releasing agents (DRAs), peripheral catechol-O-methyltransferase (COMT) inhibitors, and monoamine oxidase (MAO) inhibitors Therapy for Parkinson’s syndromes...