Edaravone Pfizer

Edaravone Pfizer is indicated for the treatment of amyotrophic lateral sclerosis (ALS).

Dosage Information

The recommended dosage of Edaravone Pfizer is an intravenous infusion of 60 mg administered over a 60-minute period according to the following schedule:

• An initial treatment cycle with daily dosing for 14 days, followed by a 14-day drug-free period
• Subsequent treatment cycles with daily dosing for 10 days out of 14-day periods, followed by 14-day drug-free periods.

Preparation And Administration Information

Edaravone Pfizer is for intravenous infusion only.

Preparation

Do not use if the oxygen indicator has turned blue or purple before opening the package. Once the overwrap package is opened, use within 24 hours.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

Administration

Administer each 60 mg dose of Edaravone Pfizer injection as two consecutive 30 mg intravenous infusion bags over a total of 60 minutes (infusion rate approximately 1 mg per minute [3.33 mL per minute]).

Promptly discontinue the infusion upon the first observation of any signs or symptoms consistent with a hypersensitivity reaction.

Other medications should not be injected into the infusion bag or mixed with Edaravone Pfizer.

Edaravone Pfizer is contraindicated in patients with a history of hypersensitivity to edaravone or any of the inactive ingredients of this product. Hypersensitivity reactions and anaphylactic reactions have occurred

WARNINGS

Included as part of the "PRECAUTIONS" Section

PRECAUTIONS

Hypersensitivity Reactions

Hypersensitivity reactions (redness, wheals, and erythema multiforme) and cases of anaphylaxis (urticaria, decreased blood pressure, and dyspnea) have been reported in spontaneous postmarketing reports with Edaravone Pfizer.

Patients should be monitored carefully for hypersensitivity reactions. If hypersensitivity reactions occur, discontinue Edaravone Pfizer, treat per standard of care, and monitor until the condition resolves.

Sulfite Allergic Reactions

Edaravone Pfizer contains sodium bisulfite, a sulfite that may cause allergic type reactions, including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown. Sulfite sensitivity occurs more frequently in asthmatic people.

Patient Counseling Information

Advise the patients to read the FDA-approved patient labeling (PATIENT INFORMATION).

Hypersensitivity Reactions

Advise patients to seek immediate medical care if they experience signs or symptoms of a hypersensitivity reaction.

Sulfite Allergic Reactions

Advise patients about potential for sulfite sensitivity. Inform patients that Edaravone Pfizer contains sodium bisulfite, which may cause allergic type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes, and to seek immediate medical care if they experience these signs or symptoms.

Pregnancy And Breastfeeding

Advise patients to notify their healthcare provider if they become pregnant or intend to become pregnant during Edaravone Pfizer therapy.

Advise patients to notify their healthcare provider if they intend breastfeed or are breastfeeding an infant.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment Of Fertility

Carcinogenesis

The carcinogenic potential of edaravone has not been adequately assessed.

Mutagenesis

Edaravone was negative in in vitro (bacterial reverse mutation and Chinese hamster lung chromosomal aberration) and in vivo (mouse micronucleus) assays.

Impairment Of Fertility

Intravenous administration of edaravone (0, 3, 20, or 200 mg/kg) prior to and throughout mating in males and females and continuing in females to gestation day 7 had no effect on fertility; however, disruption of the estrus cycle and mating behavior was observed at the highest dose tested. No effects on reproductive function were observed at the lower doses, which are up to 3 times the RHD of 60 mg, on a body surface area (mg/m²) basis.

Use In Specific Populations

Pregnancy

Risk Summary

There are no adequate data on the developmental risk associated with the use of Edaravone Pfizer in pregnant women. In animal studies, administration of edaravone to pregnant rats and rabbits resulted in adverse developmental effects (increased mortality, decreased growth, delayed sexual development, and altered behavior) at clinically relevant doses. Most of these effects occurred at doses that were also associated with maternal toxicity (see Animal Data).

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk for major birth defects and miscarriage in patients with ALS is unknown.

Data

Animal Data

In rats, intravenous administration of edaravone (0, 3, 30, or 300 mg/kg/day) throughout the period of organogenesis resulted in reduced fetal weight at all doses. In dams allowed to deliver naturally, offspring weight was reduced at the highest dose tested. Maternal toxicity was also observed at the highest dose tested. There were no adverse effects on reproductive function in the offspring. A no-effect dose for embryofetal developmental toxicity was not identified; the low dose is less than the recommended human dose of 60 mg, on a body surface area (mg/m²) basis.M

In rabbits, intravenous administration of edaravone (0, 3, 20, or 100 mg/kg/day) throughout the period of organogenesis resulted in embryofetal death at the highest dose tested, which was associated with maternal toxicity. The higher no-effect dose for embryofetal developmental toxicity is approximately 6 times the recommended human dose (RHD) on a body surface area (mg/m²) basis.

The effects on offspring of edaravone (0, 3, 20, or 200 mg/kg/day), administered by intravenous injection to rats from GD 17 throughout lactation, were assessed in two studies. In the first study, offspring mortality was observed at the high dose and increased activity was observed at the mid and high doses. In the second study, there was an increase in stillbirths, offspring mortality, and delayed physical development (vaginal opening) at the highest dose tested. Reproduction function in offspring was not affected in either study. Maternal toxicity was evident in both studies at all but the lowest dose tested. The no-effect dose for developmental toxicity (3 mg/kg/day) is less than the RHD on a mg/m² basis.

Lactation

Risk Summary

There are no data on the presence of edaravone in human milk, the effects on the breastfed infant, or the effects of the drug on milk production. Edaravone and its metabolites are excreted in the milk of lactating rats. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for Edaravone Pfizer and any potential adverse effects on the breastfed infant from Edaravone Pfizer or from the underlying maternal condition.

Pediatric Use

Safety and effectiveness of Edaravone Pfizer in pediatric patients have not been established.

Geriatric Use

Of the 184 patients with ALS who received Edaravone Pfizer in 3 placebo-controlled clinical trials, a total of 53 patients were 65 years of age and older, including 2 patients 75 years of age and older. No overall differences in safety or effectiveness were observed between these patients and younger patients, but greater sensitivity of some older individuals cannot be ruled out.

Renal Impairment

The effect of renal impairment on the pharmacokinetics of Edaravone Pfizer has not been studied. However, renal impairment is not expected to significantly affect the exposure to edaravone. No dose adjustment is needed in these patients.

Hepatic Impairment

The effect of hepatic impairment on the pharmacokinetics of Edaravone Pfizer has not been studied. No dose adjustment is needed for patients with mild or moderate hepatic impairment. No specific dosing recommendation can be provided for patients with severe hepatic impairment.

The following serious adverse reactions are described elsewhere in the labeling:

• Hypersensitivity Reactions
• Sulfite Allergic Reactions

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.

In randomized, placebo-controlled trials, 184 ALS patients were administered Edaravone Pfizer 60 mg in treatment cycles for 6 months. The population consisted of Japanese patients who had a median age of 60 years (range 29- 75) and were 59% male. Most (93%) of these patients were living independently at the time of screening.

Most Common Adverse Reactions Observed During Clinical Studies

Table 1 lists the adverse reactions that occurred in ≥2% of patients in the Edaravone Pfizer-treated group and that occurred at least 2% more frequently than in the placebo-treated group in randomized placebo-controlled ALS trials. The most common adverse reactions that occurred in ≥10% of Edaravone Pfizer-treated patients were contusion, gait disturbance, and headache.

Table 1: Adverse Reactions from Pooled Placebo-Controlled Trials^a that Occurred in ≥ 2% of Edaravone Pfizer-Treated Patients and ≥ 2% More Frequently than in Placebo Patients

Postmarketing Experience

The following adverse reactions have been identified during postapproval use of Edaravone Pfizer outside of the United States. Because these reactions are 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.

Skin And Subcutaneous Tissue Disorders

Hypersensitivity reactions and anaphylaxis.

No Information Provided

Edaravone Pfizer is administered by IV infusion. The maximum plasma concentration (Cmax) of edaravone was reached by the end of infusion. There was a trend of more than dose-proportional increase in area under the concentration-time curve (AUC) and Cmax of edaravone. With multiple-dose administration, edaravone does not accumulate in plasma.

Distribution

Edaravone is bound to human serum proteins (92%), mainly to albumin, with no concentration dependence in the range of 0.1 to 50 micromol/L.

Elimination

The mean terminal elimination half-life of edaravone is 4.5 to 6 hours. The half-lives of its metabolites are 2 to 2.8 hours.

Metabolism

Edaravone is metabolized to a sulfate conjugate and a glucuronide conjugate, which are not pharmacologically active. The glucuronide conjugation of edaravone involves multiple uridine diphosphate glucuronosyltransferase (UGT) isoforms (UGT1A6, UGT1A9, UGT2B7, and UGT2B17) in the liver and kidney. In human plasma, edaravone is mainly detected as the sulfate conjugate, which is presumed to be formed by sulfotransferases.

Excretion

In Japanese and Caucasian healthy volunteer studies, edaravone was excreted mainly in the urine as its glucuronide conjugate form (70-90% of the dose). Approximately 5-10% of the dose was recovered in the urine as sulfate conjugate, and only 1% of the dose or less was recovered in the urine as unchanged form. In vitro studies suggest that sulfate conjugate of edaravone is hydrolyzed back to edaravone, which is then converted to the glucuronide conjugate in the human kidney before excretion into the urine.