WARNINGS AND PRECAUTIONS
Nephrogenic Systemic Fibrosis (NSF)
Gadolinium-based contrast agents increase the risk for nephrogenic systemic fibrosis (NSF) in patients with acute or chronic severe renal insufficiency (glomerular filtration rate < 30 mL/min/1.73 m2) and in patients with acute renal insufficiency of any severity due to the hepato-renal syndrome or in the perioperative liver transplantation period. In these patients, avoid use of gadolinium-based contrast agents unless the diagnostic information is essential and not available with non-contrast enhanced MRI. For patients receiving hemodialysis, physicians may consider the prompt initiation of hemodialysis following the administration of a gadolinium-based contrast agent in order to enhance the contrast agent's elimination. The usefulness of hemodialysis in the prevention of NSF is unknown.
Among the factors that may increase the risk for NSF are repeated or higher than recommended doses of a gadolinium-based contrast agent and the degree of renal function impairment at the time of exposure.
Post-marketing reports have identified the development of NSF following single and multiple administrations of gadolinium-based contrast agents. These reports have not always identified a specific agent. Where a specific agent was identified, the most commonly reported agent was gadodiamide (OmniscanTM), followed by gadopentetate dimeglumine (Magnevist®) and gadoversetamide (OptiMARK®). NSF has also developed following sequential administrations of gadodiamide with gadobenate dimeglumine (MultiHance®) or gadoteridol (ProHance®). The number of post-marketing reports is subject to change over time and may not reflect the true proportion of cases associated with any specific gadolinium-based contrast agent.
The extent of risk for NSF following exposure to any specific gadolinium-based contrast agent is unknown and may vary among the agents. Published reports are limited and predominantly estimate NSF risks with gadodiamide. In one retrospective study of 370 patients with severe renal insufficiency who received gadodiamide, the estimated risk for development of NSF was 4% (J Am Soc Nephrol 2006; 17:2359). The risk, if any, for the development of NSF among patients with mild to moderate renal insufficiency or normal renal function is unknown.
Screen all patients for renal dysfunction by obtaining a history and/or laboratory tests. When administering a gadolinium-based contrast agent, do not exceed the recommended dose and allow a sufficient period of time for elimination of the agent prior to any readministration. (See
DOSAGE AND ADMINISTRATION).
Anaphylactoid and anaphylactic reactions with cardiovascular, respiratory and/or cutaneous manifestations rarely resulting in death have occurred. If such a reaction occurs, stop MAGNEVIST Injection and immediately begin appropriate therapy, including resuscitation.
Observe closely patients with a history of drug reactions, allergy or other hypersensitivity disorders, during and up to several hours after MAGNEVIST Injection.
Acute renal failure
In patients with renal insufficiency, acute renal failure requiring dialysis or worsening renal function have occurred, mostly within 48 hrs of MAGNEVIST Injection. The risk of these events is higher with increasing dose of contrast. Use the lowest possible dose and evaluate renal function in patients with renal insufficiency.
MAGNEVIST is cleared by glomerular filtration and is dialyzable.
Injection site reactions
Skin and soft tissue necrosis, thrombosis, fasciitis, and compartment syndrome requiring surgical intervention (e.g. compartment release or amputation) have occurred very rarely at the site of contrast injection or the dosed limb. Total volume and rate of MAGNEVIST Injection, extravasation of contrast agent, and patient susceptibility might contribute to these reactions. Phlebitis and thrombophlebitis may be observed generally within 24 hours after MAGNEVIST Injection and resolve with supportive treatment. Determine the patency and integrity of the intravenous line before administration of MAGNEVIST Injection. Assessment of the dosed limb for the development of injection site reactions is recommended.
Interference with Visualization of lesions visible with non-contrast MRI
As with any paramagnetic contrast agent, MAGNEVIST Injection might impair the visualization of lesions seen on non-contrast MRI. Therefore, caution should be exercised when MAGNEVIST MRI scans are interpreted without a companion non-contrast MRI scan.
Patient counseling information
Patients scheduled to receive MAGNEVIST Injection should be instructed to inform their physician if they are pregnant, breast feed, or have a history of renal insufficiency, asthma or allergic respiratory disorders.
LABORATORY TEST FINDINGS
Transitory changes in serum iron, bilirubin and transaminase levels were observed in clinical trials.
MAGNEVIST Injection does not interfere with serum and plasma calcium measurements determined by colorimetric assays.
CARCINOGENESIS, MUTAGENESIS AND IMPAIRMENT OF FERTILITY
Long term animal studies have not been performed to evaluate the carcinogenic potential of gadopentetate dimeglumine.
A comprehensive battery of in vitro and in vivo studies in bacterial and mammalian systems suggest that gadopentetate dimeglumine is not mutagenic or clastogenic and does not induce unscheduled DNA repair in rat hepatocytes or cause cellular transformation of mouse embryo fibroblasts. However, the drug did show some evidence of mutagenic potential in vivo in the mouse dominant lethal assay at doses of 6 mmol/kg, but did not show any such potential in the mouse and dog micronucleus tests at intravenous doses of 9 mmol/kg and 2.5 mmol/kg, respectively.
When administered intra-peritoneally to male and female rats daily prior to mating, during mating and during embryonic development for up to 74 days (males) or 35 days (females), gadopentetate caused a decrease in number of corpora lutea at the 0.1 mmol/ kg dose level. After daily dosing with 2.5 mmol/kg suppression of food consumption and body weight gain (males and females) and a decrease in the weights of testes and epididymis were also observed.
In a separate experiment in rats, daily injections of gadopentetate dimeglumine over 16 days caused spermatogenic cell atrophy at a dose level of 5 mmol/kg but not at a dose level of 2.5 mmol/kg. This atrophy was not reversed within a 16-day observation period following the discontinuation of the drug.
PREGNANCY CATEGORY C.
Gadopentetate dimeglumine retarded fetal development slightly when given intravenously for 10 consecutive days to pregnant rats at daily doses of 0.25, 0.75, and 1.25 mmol/kg (2.5, 7.5 and 12.5 times the human dose based on body weight) and when given intravenously for 13 consecutive days to pregnant rabbits at daily doses of 0.75 and 1.25 mmol/kg (7.5 and 12.5 times the human dose respectively, based on body weight) but not at daily doses of 0.25 mmol/kg. No congenital anomalies were noted in rats or rabbits.
Adequate and well controlled studies were not conducted in pregnant women. MAGNEVIST Injection should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
MAGNEVIST is excreted in human milk. MAGNEVIST Injection was administered intravenously to 18 lactating women with normal renal function at a dose of 0.1 mmol/kg body weight. In these women, less than 0.04% of the administered gadolinium was excreted into the breast milk during the 24-hour period following dosing. Breast milk obtained during the 24 hours following dosing revealed the average cumulative amount of gadolinium excreted in breast milk was 0.57+/-0.71 micromol. The amount transferred from a 70 kg woman (receiving 0.1 mmol/kg body weight) to an infant by breast feeding over a period of 24 hrs translates into less than 3 micromol of gadolinium.
The overall duration of excretion of gadolinium into breast milk is unknown. The extent of the absorption of MAGNEVIST Injection in infants and its effect on the breast-fed child remains unknown. Caution should be exercised when MAGNEVIST Injection is administered to a nursing woman.
The use of MAGNEVIST in imaging the Central Nervous System, Extracranial/ Extraspinal tissues, and Body have been established in the pediatric population from the ages of 2 to 16 years on the basis of adequate and well controlled clinical trials in adults and safety studies in this pediatric population. (See
Safety and efficacy in the pediatric population under the age of 2 years have not been established. MAGNEVIST is eliminated primarily by the kidney. The pharmacokinetics of MAGNEVIST in neonates and infants with immature renal function have not been studied. (See
DOSAGE AND ADMINISTRATION)