Divalproex Sodium

Description

11 DESCRIPTION Divalproex sodium is a stable co-ordination compound comprised of sodium valproate and valproic acid in a 1:1 molar relationship. Chemically it is designated as sodium hydrogen bis(2-propylpentanoate). Divalproex sodium has the following structure: Divalproex sodium USP occurs as a white crystalline powder with a characteristic odor. Divalproex sodium delayed-release tablets, USP are for oral administration. Divalproex sodium delayed-release tablets, USP are supplied in three dosage strengths containing divalproex sodium USP equivalent to 125 mg, 250 mg, or 500 mg of valproic acid. Inactive Ingredients Divalproex sodium delayed-release tablets, USP: silicon dioxide, microcrystalline cellulose, croscarmellose sodium, povidone (Kollidon 30), hydroxypropyl cellulose low substituted, talc, methacrylic acid and ethyl acrylate copolymer dispersion, and diethyl phthalate. In addition, 125 mg tablets are coated with opadry clear 04K59023 and opadry II complete film coating system 86G540000 pink. Opadry clear 04K59023 contains hypromellose and triacetin, opadry II complete film coating system 86G540000 pink contains polyvinyl alcohol, talc, titanium dioxide, macrogol/PEG 3350, FD&C Red #40, lecithin (soya), and vanillin. 250 mg tablets are coated with opadry clear 04K59023 and opadry II 86G53866 orange. Opadry clear 04K59023 contains hypromellose and triacetin, opadry II 86G53866 orange contains polyvinyl alcohol, talc, titanium dioxide, macrogol/PEG 3350, lecithin (soya), vanillin, FD&C Yellow #6, and iron oxide yellow. 500 mg tablets are coated with opadry clear 04K59023 and opadry II 86G84795 pink. Opadry clear 04K59023 contains hypromellose and triacetin, opadry II 86G84795 pink contains polyvinyl alcohol, talc, titanium dioxide, macrogol/PEG 3350, lecithin (soya), FD&C Red #40, vanillin, and FD&C Blue #2. The tablets are printed with opacode black S-1-17823 containing shellac glaze in ethanol, isopropyl alcohol, iron oxide black, N-butyl alcohol,...

What Is Divalproex Sodium Used For?

1 INDICATIONS AND USAGE Divalproex sodium is an anti-epileptic drug indicated for: Treatment of manic episodes associated with bipolar disorder (1.1) Monotherapy and adjunctive therapy of complex partial seizures and simple and complex absence seizures; adjunctive therapy in patients with multiple seizure types that include absence seizures (1.2) Prophylaxis of migraine headaches (1.3) 1.1 Mania Divalproex sodium delayed-release tablets are a valproate and are indicated for the treatment of the manic episodes associated with bipolar disorder. A manic episode is a distinct period of abnormally and persistently elevated, expansive, or irritable mood. Typical symptoms of mania include pressure of speech, motor hyperactivity, reduced need for sleep, flight of ideas, grandiosity, poor judgment, aggressiveness, and possible hostility. The efficacy of divalproex sodium delayed-release tablets was established in 3-week trials with patients meeting DSM-III-R criteria for bipolar disorder who were hospitalized for acute mania [see Clinical Studies (14.1) ] . The safety and effectiveness of divalproex sodium delayed-release tablets for long-term use in mania, i.e., more than 3 weeks, has not been demonstrated in controlled clinical trials. Therefore, healthcare providers who elect to use divalproex sodium delayed-release tablets for extended periods should continually reevaluate the long-term usefulness of the drug for the individual patient. 1.2 Epilepsy Divalproex sodium delayed-release tablets are indicated as monotherapy and adjunctive therapy in the treatment of patients with complex partial seizures that occur either in isolation or in association with other types of seizures. Divalproex sodium delayed-release tablets are also indicated for use as sole and adjunctive therapy in the treatment of simple and complex absence seizures, and adjunctively in patients with multiple seizure types that include absence seizures. Simple absence is defined as very brief clouding of the sensorium or loss of consciousness accompanied by certain generalized epileptic discharges without other detectable clinical signs. Complex absence is the term used when other signs are also present. 1.3 Migraine Divalproex sodium delayed-release tablets are indicated for prophylaxis of migraine headaches. There is no evidence that divalproex sodium delayed-release tablets are useful in the acute treatment of migraine headaches. 1.4 Important Limitations Because of the risk to the fetus of decreased IQ, neurodevelopmental disorders, neural tube defects, and other major congenital malformations, which may occur very early in pregnancy, valproate should not be used to treat women with epilepsy or bipolar disorder who are pregnant or who plan to become pregnant unless other medications have failed to provide adequate symptom control or are otherwise unacceptable. Valproate should not be administered to a woman of childbearing potential unless other medications have failed to provide...

Dosage and Administration

2 DOSAGE AND ADMINISTRATION Divalproex sodium delayed-release tablets are intended for oral administration. Divalproex sodium delayed-release tablets should be swallowed whole and should not be crushed or chewed. Patients should be informed to take divalproex sodium delayed-release tablets every day as prescribed. If a dose is missed it should be taken as soon as possible, unless it is almost time for the next dose. If a dose is skipped, the patient should not double the next dose. Divalproex sodium delayed-release tablets are administered orally in divided doses. Divalproex sodium delayed-release tablets should be swallowed whole and should not be crushed or chewed (2.1, 2.2) . Mania: Initial dose is 750 mg daily, increasing as rapidly as possible to achieve therapeutic response or desired plasma level (2.1) . The maximum recommended dosage is 60 mg/kg/day (2.1, 2.2) . Complex Partial Seizures: Start at 10 to 15 mg/kg/day, increasing at 1 week intervals by 5 to 10 mg/kg/day to achieve optimal clinical response; if response is not satisfactory, check valproate plasma level; see full prescribing information for conversion to monotherapy (2.2) . The maximum recommended dosage is 60 mg/kg/day (2.1, 2.2) . Absence Seizures: Start at 15 mg/kg/day, increasing at 1 week intervals by 5 to 10 mg/kg/day until seizure control or limiting side effects (2.2) . The maximum recommended dosage is 60 mg/kg/day (2.1, 2.2) . Migraine: The recommended starting dose is 250 mg twice daily, thereafter increasing to a maximum of 1,000 mg/day as needed (2.3) . 2.1 Mania Divalproex sodium delayed-release tablets are administered orally. The recommended initial dose is 750 mg daily in divided doses. The dose should be increased as rapidly as possible to achieve the lowest therapeutic dose which produces the desired clinical effect or the desired range of plasma concentrations. In placebo-controlled clinical trials of acute mania, patients were dosed to a clinical response with a trough plasma concentration between 50 and 125 mcg/mL. Maximum concentrations were generally achieved within 14 days. The maximum recommended dosage is 60 mg/kg/day. There is no body of evidence available from controlled trials to guide a clinician in the longer term management of a patient who improves during divalproex sodium delayed-release tablets treatment of an acute manic episode. While it is generally agreed that pharmacological treatment beyond an acute response in mania is desirable, both for maintenance of the initial response and for prevention of new manic episodes, there are no data to support the benefits of divalproex sodium delayed-release tablets in such longer-term treatment. Although there are no efficacy data that specifically address longer-term antimanic treatment with divalproex sodium delayed-release tablets, the safety of divalproex sodium delayed-release tablets in long-term use is supported by data from record reviews involving approximately 360 patients treated with...

Side Effects (Adverse Reactions)

6 ADVERSE REACTIONS The following serious adverse reactions are described below and elsewhere in the labeling: Hepatic Failure [see Warnings and Precautions (5.1) ] Birth Defects [see Warnings and Precautions (5.2) ] Decreased IQ Following in Utero Exposure [see Warnings and Precautions (5.3) ] Pancreatitis [see Warnings and Precautions (5.5) ] Hyperammonemic Encephalopathy [see Warnings and Precautions (5.6 , 5.9 , 5.10) ] Suicidal Behavior and Ideation [see Warnings and Precautions (5.7) ] Bleeding and Other Hematopoietic Disorders [see Warnings and Precautions (5.8) ] Hypothermia [see Warnings and Precautions (5.11) ] Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)/Multiorgan Hypersensitivity Reactions [see Warnings and Precautions (5.12) ] Serious Dermatologic Reactions [see Warnings and Precautions (5.13) ] Angioedema [see Warnings and Precautions (5.14) ] Somnolence in the Elderly [see Warnings and Precautions (5.16) ] Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice. Most common adverse reactions (reported ≥15% for any indication) are abdominal pain, alopecia, asthenia, diarrhea, diplopia, dizziness, headache, infection, insomnia, nausea, somnolence, thrombocytopenia, tremor, vomiting ( 6.1 , 6.2 , 6.3 ). The safety and tolerability of valproate in pediatric patients were shown to be comparable to those in adults (8.4) . To report SUSPECTED ADVERSE REACTIONS, contact Rising Pharma Holdings, Inc. at 1-844-874-7464 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Mania The incidence of treatment-emergent events has been ascertained based on combined data from two three week placebo-controlled clinical trials of divalproex sodium delayed-release tablets in the treatment of manic episodes associated with bipolar disorder. The adverse reactions were usually mild or moderate in intensity, but sometimes were serious enough to interrupt treatment. In clinical trials, the rates of premature termination due to intolerance were not statistically different between placebo, divalproex sodium delayed-release tablets, and lithium carbonate. A total of 4%, 8% and 11% of patients discontinued therapy due to intolerance in the placebo, divalproex sodium delayed-release tablets, and lithium carbonate groups, respectively. Table 2 summarizes those adverse reactions reported for patients in these trials where the incidence rate in the divalproex sodium delayed-release tablets-treated group was greater than 5% and greater than the placebo incidence, or where the incidence in the divalproex sodium delayed-release tablets-treated group was statistically significantly greater than the placebo group. Vomiting was the only reaction that was reported by significantly (p ≤ 0.05) more patients receiving divalproex sodium delayed-release tablets compared to placebo. Table 2. Adverse Reactions Reported by > 5% of Divalproex Sodium Delayed-Release Tablets-Treated Patients During Placebo-Controlled Trials of Acute Mania 1 Adverse Reaction Divalproex Sodium Delayed-Release Tablets (n = 89) % Placebo (n = 97) % 1 The following adverse reactions occurred at an equal or greater incidence for placebo than for divalproex sodium delayed-release tablets: back pain, headache, constipation, diarrhea, tremor, and pharyngitis. Nausea 22 15 Somnolence 19 12 Dizziness 12 4 Vomiting 12 3 Accidental Injury 11 5 Asthenia 10 7 Abdominal Pain 9 8 Dyspepsia 9 8 Rash 6 3 The following additional adverse reactions were reported by greater than 1% but not more than 5% of the 89 divalproex sodium delayed-release tablets-treated patients in controlled clinical trials: Body as a Whole: Chest pain, chills, chills and fever, fever, neck pain, neck rigidity. Cardiovascular System : Hypertension, hypotension, palpitations, postural hypotension,...

Drug Interactions

7 DRUG INTERACTIONS Hepatic enzyme-inducing drugs (e.g., phenytoin, carbamazepine, phenobarbital, primidone, rifampin) can increase valproate clearance, while enzyme inhibitors (e.g., felbamate) can decrease valproate clearance. Therefore increased monitoring of valproate and concomitant drug concentrations and dosage adjustment are indicated whenever enzyme-inducing or inhibiting drugs are introduced or withdrawn (7.1) Aspirin, carbapenem antibiotics, estrogen-containing hormonal contraceptives, methotrexate: Monitoring of valproate concentrations is recommended ( 7.1 ) Co-administration of valproate can affect the pharmacokinetics of other drugs (e.g., diazepam, ethosuximide, lamotrigine, phenytoin) by inhibiting their metabolism or protein binding displacement (7.2) Patients stabilized on rufinamide should begin valproate therapy at a low dose, and titrate to clinically effective dose ( 7.2 ) Dosage adjustment of amitriptyline/nortriptyline, propofol, warfarin, and zidovudine may be necessary if used concomitantly with divalproex sodium delayed-release tablets (7.2) Topiramate: Hyperammonemia and encephalopathy (5.10, 7.3) Cannabidiol: ALT and/or AST elevation ( 7.4 ) 7.1 Effects of Co-Administered Drugs on Valproate Clearance Drugs that affect the level of expression of hepatic enzymes, particularly those that elevate levels of glucuronosyltransferases (such as ritonavir), may increase the clearance of valproate. For example, phenytoin, carbamazepine, and phenobarbital (or primidone) can double the clearance of valproate. Thus, patients on monotherapy will generally have longer half-lives and higher concentrations than patients receiving polytherapy with antiepilepsy drugs. In contrast, drugs that are inhibitors of cytochrome P450 isozymes, e.g., antidepressants, may be expected to have little effect on valproate clearance because cytochrome P450 microsomal mediated oxidation is a relatively minor secondary metabolic pathway compared to glucuronidation and beta-oxidation. Because of these changes in valproate clearance, monitoring of valproate and concomitant drug concentrations should be increased whenever enzyme inducing drugs are introduced or withdrawn. The following list provides information about the potential for an influence of several commonly prescribed medications on valproate pharmacokinetics. The list is not exhaustive nor could it be, since new interactions are continuously being reported. Drugs for which a potentially important interaction has been observed Aspirin A study involving the co-administration of aspirin at antipyretic doses (11 to 16 mg/kg) with valproate to pediatric patients (n=6) revealed a decrease in protein binding and an inhibition of metabolism of valproate. Valproate free fraction was increased 4-fold in the presence of aspirin compared to valproate alone. The β-oxidation pathway consisting of 2-E-valproic acid, 3-OH-valproic acid, and 3-keto valproic acid was decreased from 25% of total metabolites...

Contraindications

4 CONTRAINDICATIONS Divalproex sodium delayed-release tablets are contraindicated in patients: with hepatic disease or significant hepatic dysfunction [see Warnings and Precautions (5.1) ] . known to have mitochondrial disorders caused by mutations in mitochondrial DNA polymerase γ (POLG; e.g., Alpers-Huttenlocher Syndrome) and children under two years of age who are suspected of having a POLG-related disorder [see Warnings and Precautions (5.1) ]. with known hypersensitivity to divalproex sodium, sodium valproate, or valproic acid. Reactions have included multiorgan hypersensitivity, serious dermatologic reactions, and angioedema [see Warnings and Precautions (5.12 , 5.13 , 5.14) ] . with known urea cycle disorders [see Warnings and Precautions (5.6) ] . being treated for prophylaxis of migraine headaches who are pregnant or in women of childbearing potential who are not using effective contraception [see Warnings and Precautions (5.2 , 5.3 , 5.4 ) and Use in Specific Populations (8.1) ] . Hepatic disease or significant hepatic dysfunction ( 4 , 5.1 ) Known mitochondrial disorders caused by mutations in mitochondrial DNA polymerase γ (POLG) ( 4 , 5.1 ) Suspected POLG-related disorder in children under two years of age ( 4, 5.1 ) Known hypersensitivity to divalproex sodium, sodium valproate, or valproic acid ( 4 , 5.12 , 5.13 , 5.14 ) Urea cycle disorders ( 4 , 5.6) Prophylaxis of migraine headaches: Pregnant women, women of childbearing potential not using effective contraception ( 4 , 8.1 )

Pregnancy and Breastfeeding

8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to antiepileptic drugs (AEDs), including divalproex sodium delayed-release tablets, during pregnancy. Encourage women who are taking divalproex sodium delayed-release tablets during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry by calling toll-free 1-888-233-2334 or visiting the website, http://www.aedpregnancyregistry.org/. This must be done by the patient herself. Risk Summary For use in prophylaxis of migraine headaches, valproate is contraindicated in women who are pregnant and in women of childbearing potential who are not using effective contraception [see Contraindications (4)] . For use in epilepsy or bipolar disorder, valproate should not be used to treat women who are pregnant or who plan to become pregnant unless other medications have failed to provide adequate symptom control or are otherwise unacceptable [see Boxed Warning and Warnings and Precautions (5.2 , 5.3)] . Women with epilepsy who become pregnant while taking valproate should not discontinue valproate abruptly, as this can precipitate status epilepticus with resulting maternal and fetal hypoxia and threat to life. Maternal valproate use during pregnancy for any indication increases the risk of congenital malformations, particularly neural tube defects including spina bifida, but also malformations involving other body systems (e.g., craniofacial defects including oral clefts, cardiovascular malformations, hypospadias, limb malformations). This risk is dose-dependent; however, a threshold dose below which no risk exists cannot be established. In utero exposure to valproate may also result in hearing impairment or hearing loss. Valproate polytherapy with other AEDs has been associated with an increased frequency of congenital malformations compared with AED monotherapy. The risk of major structural abnormalities is greatest...

8.3 Females and Males of Reproductive Potential Contraception Women of childbearing potential should use effective contraception while taking valproate [see Boxed Warning , Warnings and Precautions (5.4) , Drug Interactions (7) , and Use in Specific Populations (8.1) ] . This is especially important when valproate use is considered for a condition not usually associated with permanent injury or death such as prophylaxis of migraine headaches [see Contraindications (4) ] . Infertility There have been reports of male infertility coincident with valproate therapy [see Adverse Reactions (6.4) ] . In animal studies, oral administration of valproate at clinically relevant doses resulted in adverse reproductive effects in males [see Nonclinical Toxicology (13.1) ] .

Overdosage

10 OVERDOSAGE Overdosage with valproate may result in somnolence, heart block, deep coma, and hypernatremia. Fatalities have been reported; however patients have recovered from valproate levels as high as 2,120 mcg/mL. In overdose situations, the fraction of drug not bound to protein is high and hemodialysis or tandem hemodialysis plus hemoperfusion may result in significant removal of drug. The benefit of gastric lavage or emesis will vary with the time since ingestion. General supportive measures should be applied with particular attention to the maintenance of adequate urinary output. Naloxone has been reported to reverse the CNS depressant effects of valproate overdosage. Because naloxone could theoretically also reverse the antiepileptic effects of valproate, it should be used with caution in patients with epilepsy.

How Supplied

16 HOW SUPPLIED/STORAGE AND HANDLING Divalproex sodium delayed-release tablets, USP are supplied as: Divalproex Sodium Delayed-Release Tablets USP, 125 mg are pink-red colored, oval shaped enteric-coated tablets, imprinted with “D 84” on one side with black edible ink and plain on other side. Bottles of 100 NDC 57237-106-01 Bottles of 500 NDC 57237-106-05 Divalproex Sodium Delayed-Release Tablets USP, 250 mg are peach colored, oval shaped enteric-coated tablets, imprinted with “D 85”on one side with black edible ink and plain on other side. Bottles of 100 NDC 57237-047-01 Bottles of 500 NDC 57237-047-05 Divalproex Sodium Delayed-Release Tablets USP, 500 mg are pink colored, oval shaped enteric-coated tablets, imprinted with “D 86” on one side with black edible ink and plain on other side. Bottles of 100 NDC 57237-048-01 Bottles of 500 NDC 57237-048-05 Recommended Storage Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature].