radium Ra 223 dichloride [IV]

Adult Dosing

Castration-resistant prostate cancer, symptomatic bone metastases and no known visceral metastatic disease

50 kBq (1.36 microcurie) per kg IV infused over 1 minute; repeat q4 wk x 6 cycles total

Note:

Volume to be administered should be calculated using the:

Patient’s body weight (kg)
Dosage level 50 kBq/kg body weight or 1.35 microcurie/kg body weight
Radioactivity concentration of the product (1,000 kBq/mL; 27 microcurie/mL) at the reference date
Decay correction factor to correct for physical decay of radium-223
Example: (Body wt in kg x 50 kBq/kg body weight)/(Decay factor x 1,000 kBq/mL)
Decay correction factor table listed in prescribing information and is based on the vial’s reference date

Pediatric Dosing

Safety and efficacy in pediatric patients have not been established

[Outline]

Adult Dosing
Pediatric Dosing

Indications ⬆ ⬇

Radioactive therapeutic agent indicated for the treatment of patients with castration-resistant prostate cancer, symptomatic bone metastases and no known visceral metastatic disease

Contraindications ⬆ ⬇

Hypersensitivity to any of the ingredients of the product
Pregnancy

Black Box Warnings ⬆ ⬇

Dosing Adjustment ⬆ ⬇

Renal Dose Adjustment

Renal impairment: No dose adjustments

Hepatic Dose Adjustment

Hepatic impairment: No dose adjustments

Warnings/Precautions ⬆ ⬇

Therapy may cause myelosuppression and bone marrow failure; perform hematologic evaluation at baseline and prior to every dose; discontinue if life-threatening complications occur despite supportive care for bone marrow failure
Deaths related to vascular hemorrhage in association with myelosuppression have been associated with the drug
Myelosuppression; notably thrombocytopenia, neutropenia, pancytopenia, and leukopenia; has been reported in patients
Hematologic evaluation of patients must be performed at baseline and prior to every dose. Before the first administration, the absolute neutrophil count (ANC) should be = > 1.5 x 10⁹/L, the platelet count = 100 x 10⁹/L and hemoglobin = > 10 g/dL
Safety and efficacy of concomitant chemotherapy have not been established; outside of a clinical trial, concomitant use with chemotherapy is not recommended due to the potential for additive myelosuppression
Because of potential effects on spermatogenesis associated with radiation, advise men who are sexually active to use condoms and their female partners of reproductive potential to use a highly effective contraceptive method during and for 6 months after completing treatment

Pregnancy/Breast Feeding ⬆ ⬇

Pregnancy Category:X; Therapy can cause fetal harm when administered to a pregnant woman based on its mechanism of action

Breastfeeding: Safety unknown; because of the potential for possible serious adverse reactions in nursing infants a decision should be made to discontinue breastfeeding, or to discontinue the drug taking into account the importance of the drug to the mother.

Adverse Reactions ⬆ ⬇

HEMA: Pancytopenia, anemia, lymphocytopenia, leukopenia, thrombocytopenia, neutropenia
GI: Nausea, diarrhea, vomiting, dehydration
GU: Renal failure and impairment
MISC: Peripheral edema, injection site erythema and pain

Clinical Pharmacology ⬆ ⬇

Alpha particle-emitting radiopharmaceutical; which mimics calcium and forms complexes with the bone mineral hydroxyapatite at areas of increased bone turnover, such as bone metastases; leading to a high frequency of double-strand DNA breaks in adjacent cells, resulting in an anti-tumor effect on bone metastases
Metabolism: Radium-223 is an isotope that decays and is not metabolized
Excretion: 63% excreted from body within 7 days after injection; Fecal excretion is the major elimination route; at 48 hr after injection, the cumulative fecal excretion was 13% (range 0 -34%), and the cumulative urine excretion was 2% (range 1 -5%)

Brands and Availability ⬆ ⬇