NephroScan™
Safety
Clinical safety
Hypersensitivity Reactions
Hypersensitivity reactions, including urticaria, rash, pruritus, and erythema have been reported with the use of technetium Tc 99m succimer injection in adults and pediatric patients. The time of onset of the reactions varied within 2 hours to several hours after the injection. Have appropriate instruments and medications necessary for immediate treatment of hypersensitivity reactions and monitor patients for reactions during and after administration [see Package Insert section 6].
Radiation Risks
Technetium Tc 99m succimer injection contributes to a patient’s overall long-term cumulative radiation exposure. Long-term cumulative radiation exposure is associated with an increased risk for cancer. Ensure safe handling to minimize radiation exposure to the patient and health care workers. Advise patients to hydrate before and after administration and to void frequently after administration [see Package Insert section 2.1 and 2.2].
Risk in Patients with Advanced Renal Failure
The use of technetium Tc 99m succimer injection in patients with severely reduced estimated glomerular filtration (eGFR) may have an effect on image interpretation as the kidneys may not absorb the technetium Tc 99m succimer and thus the Tc 99m succimer may distribute to organs or parts of the body other than the kidneys. It has been reported that satisfactory images may be obtained in some of these patients by delaying imaging between 6 hours to 24 hours [see Package Insert section 2.7].
ADVERSE REACTIONS
The following clinically significant adverse reactions are discussed elsewhere in the labeling:
• Hypersensitivity Reactions [see Package Insert section 5.1]
The following adverse reactions associated with the use of NEPHROSCAN were identified in clinical studies or postmarketing reports. Because some of these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Immune System Disorders: Hypersensitivity including urticaria, rash, pruritus, and erythema
General Disorders: syncope, fever, and nausea.
USE IN SPECIFIC POPULATIONS
Pregnancy
Risk Summary
Available data with technetium Tc 99m succimer use in pregnant women are insufficient to evaluate for a drug-associated risk of major birth defects and miscarriage. Animal reproduction studies with technetium Tc 99m succimer have not been conducted. Although all radiopharmaceuticals have the potential to cause fetal harm depending on the fetal stage of development and the magnitude of the radiation dose, the radiation exposure to the fetus from technetium Tc 99m succimer is expected to be low (less than 0.50 mGy) (see Data).
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defects, loss, or other adverse outcomes. In the U.S. general population the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies are 2% to 4% and 15% to 20%, respectively.
Data
Human Data
No adverse fetal effects of radiation risks have been identified for diagnostic procedures involving less than 50 mGy, which represents less than 10mGy fetal doses.
Lactation
Risk Summary
Technetium Tc 99m succimer is present in breast milk. There are no data on the effects of technetium Tc 99m succimer on the breastfed infant or the effects on milk production. NEPHROSCAN is used for imaging in infants with renal disease; exposure to technetium Tc 99m succimer via breast milk is expected to be lower. Based on clinical guidelines, exposure of technetium Tc 99m succimer to a breastfed infant may be minimized by advising a lactating woman to temporarily discontinue breastfeeding and to pump and discard breast milk for a minimum of at least 24 hours after administration of Technetium Tc 99m Succimer Injection. The developmental and health benefits of breastfeeding should be considered along with a mother’s clinical need for NEPHROSCAN, any potential adverse effects on the breastfed child from technetium Tc 99m succimer or from the underlying maternal condition.
Pediatric Use
NEPHROSCAN, after radiolabeling with technetium Tc 99m, is indicated for use as an aid in the scintigraphic evaluation of renal parenchymal disorders in pediatric patients, including term neonates. Use of NEPHROSCAN in this age group for this indication is supported by evidence from effectiveness established in adult studies and data from published pediatric studies supporting the safety and effectiveness of weight-based dosing of Technetium Tc 99m Succimer Injection in renal parenchymal imaging in pediatric patients including term neonates [see Package Insert section 2.3].
The recommended amount of radioactivity in pediatric patients, 1.85 MBq/kg (0.05 mCi/kg) with a range of 19 MBq to 74 MBq (0.5 mCi to 2 mCi), is based on published studies that used technetium Tc 99m succimer for the evaluation of acute pyelonephritis, renal scarring, and split renal function in pediatric patients [see Package Insert section 2.2].
Hypersensitivity reactions, including urticaria, rash, pruritus, and erythema have been reported with the use of technetium Tc 99m succimer in pediatric patients [see Package Insert sections 5.1 and 6].
Geriatric Use
Clinical studies of technetium Tc 99m succimer did not include sufficient numbers of subjects 65 years of age and over to determine whether they respond differently from younger patients. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious usually administering the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy.
This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with decreased renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
OVERDOSAGE
In the event of an overdose of technetium Tc 99m succimer, reduce the radiation absorbed dose to the patient where possible by increasing the elimination of the drug from the body using hydration and frequent bladder voiding. A diuretic might also be considered. If possible, an estimate of the radiation effective dose given to the patient should be made.