Bicalutamide

Description

11. DESCRIPTION Bicalutamide tablets, USP contain 50 mg of bicalutamide, a non-steroidal androgen receptor inhibitor with no other known endocrine activity. The chemical name is propanamide, N [4 cyano-3-(trifluoromethyl)phenyl]-3-[(4-fluorophenyl)sulfonyl]-2-hydroxy-2-methyl-,(+-). The structural and empirical formulas are: Bicalutamide has a molecular weight of 430.37. The pKa is approximately 12. Bicalutamide is a fine white to off-white powder which is practically insoluble in water at 37°C (5 mg per 1000 mL), slightly soluble in chloroform and absolute ethanol, sparingly soluble in methanol, and soluble in acetone and tetrahydrofuran. Bicalutamide is a racemate with its antiandrogenic activity being almost exclusively exhibited by the R-enantiomer of bicalutamide; the S-enantiomer is essentially inactive. The inactive ingredients of bicalutamide tablets, USP are lactose monohydrate, magnesium stearate, hypromellose E5, polyethylene glycol 400, povidone K 30, sodium starch glycolate, and titanium dioxide. Bicalutamide tablets, USP 50 mg meets USP Dissolution Test 2. chem

What Is Bicalutamide Used For?

1. INDICATIONS AND USAGE Bicalutamide tablets 50 mg daily is indicated for use in combination therapy with a luteinizing hormone-releasing hormone (LHRH) analog for the treatment of Stage D 2 metastatic carcinoma of the prostate. Bicalutamide tablets 150 mg daily is not approved for use alone or with other treatments [see Clinical Studies (14.2) ]. Bicalutamide tablets 50 mg is an androgen receptor inhibitor indicated for use in combination therapy with a luteinizing hormone-releasing hormone (LHRH) analog for the treatment of Stage D 2 metastatic carcinoma of the prostate. ( 1 ) Bicalutamide tablets 150 mg daily is not approved for use alone or with other treatments. ( 1 )

Dosage and Administration

2. DOSAGE AND ADMINISTRATION The recommended dose for bicalutamide therapy in combination with an LHRH analog is one 50 mg tablet once daily (morning or evening). ( 2 ) 2.1. Recommended Dose and Schedule The recommended dose for bicalutamide tablets therapy in combination with an LHRH analog is one 50 mg tablet once daily (morning or evening), with or without food. It is recommended that bicalutamide tablets be taken at the same time each day. Treatment with bicalutamide tablets should be started at the same time as treatment with an LHRH analog. If a dose of bicalutamide is missed, take the next dose at the scheduled time. Do not take the missed dose and do not double the next dose. 2.2. Dosage Adjustment in Renal Impairment No dosage adjustment is necessary for patients with renal impairment [see Use in Specific Populations (8.7) ] . 2.3. Dosage Adjustment in Hepatic Impairment No dosage adjustment is necessary for patients with mild to moderate hepatic impairment. In patients with severe liver impairment (n=4), although there was a 76% increase in the half-life (5.9 and 10.4 days for normal and impaired patients, respectively) of the active enantiomer of bicalutamide, no dosage adjustment is necessary [see Use in Specific Populations (8.6) ] .

Side Effects (Adverse Reactions)

6. ADVERSE REACTIONS 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. Adverse reactions that occurred in more than 10% of patients receiving bicalutamide plus an LHRH-A were: hot flashes, pain (including general, back, pelvic and abdominal), asthenia, constipation, infection, nausea, peripheral edema, dyspnea, diarrhea, hematuria, nocturia and anemia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Accord Healthcare Inc. at 1-866-941-7875 or www.accordhealthcare.us or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1. Clinical Trials Experience In patients with advanced prostate cancer treated with bicalutamide in combination with an LHRH analog, the most frequent adverse reaction was hot flashes (53%). In the multi-center, double-blind, controlled clinical trial comparing bicalutamide 50 mg once daily with flutamide 250 mg three times a day, each in combination with an LHRH analog, the following adverse reactions with an incidence of 5% or greater, regardless of causality, have been reported. Table 1. Incidence of Adverse Reactions (≥ 5% in Either Treatment Group) Regardless of Causality Body System Adverse Reaction Treatment Group Number of Patients (%) Bicalutamide Plus LHRH Analog (n=401) Flutamide Plus LHRH Analog (n=407) Body as a Whole Pain (General) 142 (35) 127 (31) Back Pain 102 (25) 105 (26) Asthenia 89 (22) 87 (21) Pelvic Pain 85 (21) 70 (17) Infection 71(18) 57 (14) Abdominal Pain 46 (11) 46 (11) Chest Pain 34 (8) 34 (8) Headache 29 (7) 27 (7) Flu Syndrome 28 (7) 30 (7) Cardiovascular Hot Flashes 211 (53) 217 (53) Hypertension 34 (8) 29 (7) Digestive Constipation 87 (22) 69 (17) Nausea 62 (15) 58 (14) Diarrhea 49 (12) 107 (26) Increased Liver Enzyme Test 30 (7) 46 (11) Dyspepsia 30 (7) 23 (6) Flatulence 26 (6) 22 (5) Anorexia 25 (6) 29 (7) Vomiting 24 (6) 32 (8) Hemic and Lymphatic Anemia 45 (11) 53 (13) Metabolic and Nutritional Peripheral Edema 53 (13) 42 (10) Weight Loss 30 (7) 39 (10) Hyperglycemia 26 (6) 27 (7) Alkaline Phosphatase Increased 22 (5) 24 (6) Weight Gain 22 (5) 18 (4) Musculoskeletal Bone Pain 37 (9) 43 (11) Myasthenia 27 (7) 19 (5) Arthritis 21 (5) 29 (7) Pathological Fracture 17 (4) 32 (8) Nervous System Dizziness 41 (10) 35 (9) Paresthesia 31 (8) 40 (10) Insomnia 27 (7) 39 (10) Anxiety 20 (5) 9 (2) Depression 16 (4) 33 (8) Respiratory System Dyspnea 51 (13) 32 (8) Cough Increased 33 (8) 24 (6) Pharyngitis 32 (8) 23 (6) Bronchitis 24 (6) 22 (3) Pneumonia 18 (4) 19 (5) Rhinitis 15 (4) 22 (5) Skin and Appendages Rash 35 (9) 30 (7) Sweating 25 (6) 20 (5) Urogenital Nocturia 49 (12) 55 (14) Hematuria 48 (12) 26 (6) Urinary Tract Infection 35 (9) 36 (9) Gynecomastia 36 (9) 30 (7) Impotence 27 (7) 35 (9) Breast Pain 23 (6) 15 (4) Urinary Frequency 23 (6) 29 (7) Urinary Retention 20 (5) 14 (3) Urinary Impaired 19 (5) 15 (4) Urinary Incontinence 15 (4) 32 (8) Other adverse reactions (greater than or equal to 2%, but less than 5%) reported in the bicalutamide-LHRH analog treatment group are listed below by body system and are in order of decreasing frequency within each body system regardless of causality. Body as a Whole: Neoplasm; Neck Pain; Fever; Chills; Sepsis; Hernia; Cyst Cardiovascular: Angina Pectoris; Congestive Heart Failure; Myocardial Infarct; Heart Arrest; Coronary Artery Disorder; Syncope Digestive: Melena; Rectal Hemorrhage; Dry Mouth; Dysphagia; Gastrointestinal Disorder; Periodontal Abscess; Gastrointestinal Carcinoma Metabolic and Nutritional: Edema; BUN Increased; Creatinine Increased; Dehydration; Gout; Hypercholesteremia Musculoskeletal: Myalgia; Leg Cramps Nervous: Hypertonia; Confusion; Somnolence; Libido Decreased; Neuropathy; Nervousness Respiratory: Lung Disorder; Asthma; Epistaxis; Sinusitis Skin and Appendages: Dry Skin; Alopecia; Pruritus; Herpes Zoster;...

Drug Interactions

7. DRUG INTERACTIONS Clinical studies have not shown any drug interactions between bicalutamide and LHRH analogs (goserelin or leuprolide). There is no evidence that bicalutamide induces hepatic enzymes. In vitro studies have shown that R-bicalutamide is an inhibitor of CYP 3A4 with lesser inhibitory effects on CYP 2C9, 2C19 and 2D6 activity. Clinical studies have shown that with co-administration of bicalutamide, mean midazolam (a CYP 3A4 substrate) levels may be increased 1.5-fold (for C max ) and 1.9-fold (for AUC). Hence, caution should be exercised when bicalutamide is co-administered with CYP 3A4 substrates. In vitro protein-binding studies have shown that bicalutamide can displace coumarin anticoagulants from binding sites. PT/INR should be closely monitored in patients concomitantly receiving coumarin anticoagulants and bicalutamide. Adjustment of the anticoagulant dose may be necessary. [see Warnings and Precautions (5.2) and Adverse reaction (6.2) ]

Contraindications

4. CONTRAINDICATIONS

Pregnancy and Breastfeeding

8.1. Pregnancy Risk Summary Bicalutamide is contraindicated for use in pregnant women because it can cause fetal harm. Bicalutamide is not indicated for use in females. There are no human data on the use of bicalutamide in pregnant women. In animal reproduction studies, oral administration of bicalutamide to pregnant rats during organogenesis caused abnormal development of reproductive organs in male fetuses at exposures approximately 0.7 to 2 times the human exposure at the recommended dose (see Data) . Data Animal Data In an embryo-fetal development study in pregnant rats dosed during the period of organogenesis from gestation days 6 to15, male fetuses had reduced anogenital distance at doses of 10 mg/kg/day and above (approximately 0.7 to 2 times the human exposure at the recommended dose). In a pre- and post-natal development study, female rats were dosed from gestation day 7 to 16 and allowed to litter and rear their offspring to weaning. Male offspring of rats receiving doses of 10 mg/kg/day (approximately 0.7 times the human exposure at the recommended dose) and above, were observed to have reduced anogenital distance. In a peri- and post-natal development study, female rats were dosed from gestation day 16 to lactation day 22 and allowed to litter and rear their offspring to weaning. Survival and weights of offspring during lactation were reduced for litters from maternal rats receiving doses of 250 mg/kg/day (approximately 2 times the human exposure at the recommended dose). Male offspring of rats receiving doses of 10 mg/kg/day (approximately 0.7 times the human exposure at the recommended dose) and above, were observed to have reduced anogenital distance, smaller secondary sex organs, cryptorchidism and hypospadias resulting in an inability to mate and impregnate their female partners. Female offspring of rats receiving doses of 10 mg/kg/day (approximately 0.7 times the human exposure at the recommended dose) and above had reduced pregnancy rates.

8.2. Lactation Risk Summary Bicalutamide is not indicated for use in pregnant women. There is no information available on the presence of bicalutamide in human milk, or on the effects on the breastfed infant or on milk production. Bicalutamide has been detected in rat milk. 8.3. Females and Males of Reproductive Potential Contraception Males Antiandrogen therapy may cause morphological changes in spermatozoa [see Nonclinical Toxicology (13.1) ]. Based on findings in animal reproduction studies and its mechanism of action, advise male patients with female partners of reproductive potential to use effective contraception during treatment and for 130 days after the final dose of bicalutamide [see Use in Specific Populations (8.1) and Clinical Pharmacology (12.1) ]. Infertility Males Based on animal studies, bicalutamide can lead to inhibition of spermatogenesis and may impair fertility in males of reproductive potential. The long-term effects of bicalutamide tablets on male fertility have not been studied. [see Error! Hyperlink reference not valid. ] .

Overdosage

10. OVERDOSAGE Long-term clinical trials have been conducted with dosages up to 200 mg of bicalutamide daily and these dosages have been well tolerated. A single dose of bicalutamide that results in symptoms of an overdose considered to be life threatening has not been established. There is no specific antidote; treatment of an overdose should be symptomatic. In the management of an overdose with bicalutamide, vomiting may be induced if the patient is alert. It should be remembered that, in this patient population, multiple drugs may have been taken. Dialysis is not likely to be helpful since bicalutamide is highly protein bound and is extensively metabolized. General supportive care, including frequent monitoring of vital signs and close observation of the patient, is indicated.

How Supplied

16. HOW SUPPLIED/STORAGE AND HANDLING Bicalutamide tablets, USP 50 mg are white to off-white, round, biconvex, film-coated tablets debossed "B 50" on one side and plain on other side and supplied in bottles of 30 tablets (NDC 71205-577-30), bottles of 60 tablets (NDC 71205-577-60, and bottles of 90 tablets (NDC 71205-577-90). 16.1. Storage and Handling “Store at 20° to 25°C (68 to 77°F). [See USP Controlled Room Temperature]”