dutasteride 0.5 MG Oral Capsule [Avodart]

INDICATIONS AND USAGE Dutasteride capsules is a 5 alpha-reductase inhibitor indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate to: ( 1.1 ) improve symptoms, reduce the risk of acute urinary retention, and reduce the risk of the need for BPH-related surgery. Dutasteride capsules in combination with the alpha-adrenergic antagonist, tamsulosin, is indicated for the treatment of symptomatic BPH in men with an enlarged prostate. (1.2) Limitations of Use: Dutasteride capsules is not approved for the prevention of prostate cancer. (1.3) 1.1 Monotherapy Dutasteride capsules are indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate to: improve symptoms, reduce the risk of acute urinary retention (AUR), and reduce the risk of the need for BPH-related surgery. 1.2 Combination with Alpha-adrenergic Antagonist Dutasteride capsules in combination with the alpha-adrenergic antagonist, tamsulosin, is indicated for the treatment of symptomatic BPH in men with an enlarged prostate. 1.3 Limitations of Use Dutasteride capsules are not approved for the prevention of prostate cancer.

DOSAGE AND ADMINISTRATION The capsules should be swallowed whole and not chewed or opened, as contact with the capsule contents may result in irritation of the oropharyngeal mucosa. Dutasteride capsules may be administered with or without food. Monotherapy: 0.5 mg once daily. ( 2.1 ) Combination with tamsulosin: 0.5 mg once daily and tamsulosin 0.4 mg once daily. ( 2.2 ) Dosing considerations: Swallow whole. May take with or without food. ( 2 ) 2.1 Monotherapy The recommended dose of dutasteride is 1 capsule (0.5 mg) taken once daily. 2.2 Combination with Alpha-adrenergic Antagonist The recommended dose of dutasteride is 1 capsule (0.5 mg) taken once daily and tamsulosin 0.4 mg taken once daily.

WARNINGS AND PRECAUTIONS Orthostatic hypotension and/or syncope can occur. Advise patients of symptoms related to postural hypotension and to avoid situations where injury could result if syncope occurs. ( 5.1 ) Do not use dutasteride and tamsulosin hydrochloride capsules with other alpha-adrenergic antagonists, as this may increase the risk of hypotension. ( 5.2 ) Dutasteride and tamsulosin hydrochloride capsules reduce serum prostate-specific antigen (PSA) concentration by approximately 50%. However, any confirmed increase in PSA while on dutasteride and tamsulosin hydrochloride capsules may signal the presence of prostate cancer and should be evaluated, even if those values are still within the normal range for untreated men. ( 5.3 ) Do not use dutasteride and tamsulosin hydrochloride capsules with strong inhibitors of cytochrome P450 (CYP) 3A4 (e.g., ketoconazole). Use caution in combination with moderate CYP3A4 inhibitors (e.g., erythromycin) or strong (e.g., paroxetine) or moderate CYP2D6 inhibitors, a combination of both CYP3A4 and CYP2D6 inhibitors, or known poor metabolizers of CYP2D6. Concomitant use with known inhibitors can cause a marked increase in drug exposure. ( 5.2 , 7.1 , 12.3 ) Exercise caution with concomitant use of phosphodiesterase-5 (PDE-5) inhibitors, as this may increase the risk of hypotension. ( 5.2 ) Drugs that contain dutasteride, including dutasteride and tamsulosin hydrochloride capsules, may increase the risk of high-grade prostate cancer. ( 5.4 , 6.1 ) Prior to initiating treatment with dutasteride and tamsulosin hydrochloride capsules, consideration should be given to other urological conditions that may cause similar symptoms. ( 5.5 ) Females who are pregnant or may be pregnant should not handle dutasteride and tamsulosin hydrochloride capsules due to potential risk to a male fetus. ( 5.6 , 8.1 ) Advise patients about the possibility and seriousness of priapism. ( 5.7 ) Patients should not donate blood until 6 months after their last dose of dutasteride and tamsulosin hydrochloride capsules. ( 5.8 ) Intraoperative Floppy Iris Syndrome has been observed during cataract and glaucoma surgery after alpha-adrenergic antagonist exposure. Advise patients considering cataract or glaucoma surgery to tell their ophthalmologist that they take or have taken dutasteride and tamsulosin hydrochloride capsules. ( 5.9 ) Exercise caution with concomitant use of warfarin. ( 5.2 , 7.2 , 12.3 ) 5.1 Orthostatic Hypotension As with other alpha-adrenergic antagonists, orthostatic hypotension (postural hypotension, dizziness, and vertigo) may occur in patients treated with tamsulosin-containing products, including dutasteride and tamsulosin hydrochloride capsules, and can result in syncope. Patients starting treatment with dutasteride and tamsulosin hydrochloride capsules should be cautioned to avoid situations where syncope could result in an injury [see Adverse Reactions ( 6.1 ) ] . 5.2 Drug-Drug Interactions Strong Inhibitors of Cytochrome P450 (CYP) 3A4 Tamsulosin-containing products, including dutasteride and tamsulosin hydrochloride capsules, should not be coadministered with strong CYP3A4 inhibitors (e.g., ketoconazole) as this can significantly increase tamsulosin exposure [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 )]. Moderate Inhibitors of CYP3A4, Inhibitors of CYP2D6, or a Combination of Both CYP3A4 and CYP2D6 Inhibitors Tamsulosin-containing products, including dutasteride and tamsulosin hydrochloride capsules, should be used with caution when coadministered with moderate inhibitors of CYP3A4 (e.g., erythromycin), strong (e.g., paroxetine) or moderate (e.g., terbinafine) inhibitors of CYP2D6, a combination of both CYP3A4 and CYP2D6 inhibitors, or in patients known to be poor metabolizers of CYP2D6, as there is a potential for significant increase in tamsulosin exposure [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 ) ] . Cimetidine Caution is advised when tamsulosin-containing products, including dutasteride and tamsulosin hydrochloride capsules, are coadministered with cimetidine [see Drug Interactions ( 7.1 ), Clinical Pharmacology ( 12.3 ) ] . Other Alpha-adrenergic Antagonists Tamsulosin-containing products, including dutasteride and tamsulosin hydrochloride capsules, should not be coadministered with other alpha-adrenergic antagonists because of the increased risk of symptomatic hypotension. Phosphodiesterase-5 (PDE-5) Inhibitors Caution is advised when alpha-adrenergic-antagonist-containing products, including dutasteride and tamsulosin hydrochloride capsules, are coadministered with PDE-5 inhibitors. Alpha-adrenergic antagonists and PDE-5 inhibitors are both vasodilators that can lower blood pressure. Concomitant use of these 2 drug classes can potentially cause symptomatic hypotension. Warfarin Caution should be exercised with concomitant administration of warfarin and tamsulosin-containing products, including dutasteride and tamsulosin hydrochloride capsules [see Drug Interactions ( 7.2 ), Clinical Pharmacology ( 12.3 ) ] . 5.3 Effects on Prostate-Specific Antigen (PSA) and the Use of PSA in Prostate Cancer Detection Coadministration of dutasteride with tamsulosin resulted in similar changes to serum PSA as with dutasteride monotherapy. In clinical trials, dutasteride reduced serum PSA concentration by approximately 50% within 3 to 6 months of treatment. This decrease was predictable over the entire range of PSA values in patients with symptomatic BPH, although it may vary in individuals. Dutasteride‑containing treatment, including dutasteride and tamsulosin hydrochloride capsules, may also cause decreases in serum PSA in the presence of prostate cancer. To interpret serial PSAs in men treated with a dutasteride-containing product, including dutasteride and tamsulosin hydrochloride capsules, a new baseline PSA should be established at least 3 months after starting treatment and PSA monitored periodically thereafter. Any confirmed increase from the lowest PSA value while on a dutasteride-containing treatment, including dutasteride and tamsulosin hydrochloride capsules, may signal the presence of prostate cancer and should be evaluated, even if PSA levels are still within the normal range for men not taking a 5-alpha-reductase inhibitor. Noncompliance with dutasteride and tamsulosin hydrochloride capsules may also affect PSA test results. To interpret an isolated PSA value in a man treated with dutasteride and tamsulosin hydrochloride capsules, for 3 months or more, the PSA value should be doubled for comparison with normal values in untreated men. The free-to-total PSA ratio (percent free PSA) remains constant, even under the influence of dutasteride. If clinicians elect to use percent free PSA as an aid in the detection of prostate cancer in men receiving dutasteride and tamsulosin hydrochloride capsules, no adjustment to its value appears necessary. 5.4 Increased Risk of High-Grade Prostate Cancer In men aged 50 to 75 years with a prior negative biopsy for prostate cancer and a baseline PSA between 2.5 ng/mL and 10.0 ng/mL taking dutasteride in the 4-year Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, there was an increased incidence of Gleason score 8 to 10 prostate cancer compared with men taking placebo (dutasteride 1.0% versus placebo 0.5%) [see Indications and Usage ( 1.2 ), Adverse Reactions ( 6.1 ) ] . In a 7-year placebo-controlled clinical trial with another 5-alpha-reductase inhibitor (finasteride 5 mg, PROSCAR), similar results for Gleason score 8 to 10 prostate cancer were observed (finasteride 1.8% versus placebo 1.1%). 5-alpha-reductase inhibitors may increase the risk of development of high-grade prostate cancer. Whether the effect of 5-alpha-reductase inhibitors to reduce prostate volume or trial‑related factors impacted the results of these trials has not been established. 5.5 Evaluation for Other Urological Diseases Prior to initiating treatment

CONTRAINDICATIONS Dutasteride is contraindicated for use in: • Pregnancy. In animal reproduction and developmental toxicity studies, dutasteride inhibited development of male fetus external genitalia. Therefore, dutasteride may cause fetal harm when administered to a pregnant woman. If dutasteride is used during pregnancy or if the patient becomes pregnant while taking dutasteride, the patient should be apprised of the potential hazard to the fetus [see Warnings and Precautions (5.4), Use in Specific Populations ( Error! Hyperlink reference not valid. )] . • Women of childbearing potential [see Warnings and Precautions ( 5.4 ), Use in Specific Populations ( Error! Hyperlink reference not valid. )] . • Pediatric patients [see Use in Specific Populations ( 8.4 )] . • Patients with previously demonstrated clinically significant hypersensitivity (e.g., serious skin reactions, angioedema) to dutasteride or other 5 alpha-reductase inhibitors [see Adverse Reactions ( 6.2 )] . • Pregnancy and women of childbearing potential. ( 4 , 5.4 , 8.1 ) • Pediatric patients. ( 4 ) • Patients with previously demonstrated, clinically significant hypersensitivity (e.g., serious skin reactions, angioedema) to dutasteride or other 5 alpha-reductase inhibitors. ( 4 )

CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Dutasteride inhibits the conversion of testosterone to DHT. DHT is the androgen primarily responsible for the initial development and subsequent enlargement of the prostate gland. Testosterone is converted to DHT by the enzyme 5 alpha-reductase, which exists as 2 isoforms, type 1 and type 2. The type 2 isoenzyme is primarily active in the reproductive tissues, while the type 1 isoenzyme is also responsible for testosterone conversion in the skin and liver. Dutasteride is a competitive and specific inhibitor of both type 1 and type 2 5 alpha-reductase isoenzymes, with which it forms a stable enzyme complex. Dissociation from this complex has been evaluated under in vitro and in vivo conditions and is extremely slow. Dutasteride does not bind to the human androgen receptor. 12.2 Pharmacodynamics Effect on 5 Alpha-Dihydrotestosterone and Testosterone The maximum effect of daily doses of dutasteride on the reduction of DHT is dose dependent and is observed within 1 to 2 weeks. After 1 and 2 weeks of daily dosing with dutasteride 0.5 mg, median serum DHT concentrations were reduced by 85% and 90%, respectively. In patients with BPH treated with dutasteride 0.5 mg/day for 4 years, the median decrease in serum DHT was 94% at 1 year, 93% at 2 years, and 95% at both 3 and 4 years. The median increase in serum testosterone was 19% at both 1 and 2 years, 26% at 3 years, and 22% at 4 years, but the mean and median levels remained within the physiologic range. In patients with BPH treated with 5 mg/day of dutasteride or placebo for up to 12 weeks prior to transurethral resection of the prostate, mean DHT concentrations in prostatic tissue were significantly lower in the dutasteride group compared with placebo (784 and 5,793 pg/g, respectively, P <0.001). Mean prostatic tissue concentrations of testosterone were significantly higher in the dutasteride group compared with placebo (2,073 and 93 pg/g, respectively, P <0.001). Adult males with genetically inherited type 2 5 alpha-reductase deficiency also have decreased DHT levels. These 5 alpha-reductase-deficient males have a small prostate gland throughout life and do not develop BPH. Except for the associated urogenital defects present at birth, no other clinical abnormalities related to 5 alpha-reductase deficiency have been observed in these individuals. Effects on Other Hormones In healthy volunteers, 52 weeks of treatment with dutasteride 0.5 mg/day (n = 26) resulted in no clinically significant change compared with placebo (n = 23) in sex hormone-binding globulin, estradiol, luteinizing hormone, follicle-stimulating hormone, thyroxine (free T4), and dehydroepiandrosterone. Statistically significant, baseline-adjusted mean increases compared with placebo were observed for total testosterone at 8 weeks (97.1 ng/dL, P <0.003) and thyroid-stimulating hormone at 52 weeks (0.4 mcIU/mL, P <0.05). The median percentage changes from baseline within the dutasteride group were 17.9% for testosterone at 8 weeks and 12.4% for thyroid-stimulating hormone at 52 weeks. After stopping dutasteride for 24 weeks, the mean levels of testosterone and thyroid-stimulating hormone had returned to baseline in the group of subjects with available data at the visit. In subjects with BPH treated with dutasteride in a large randomized, double-blind, placebo-controlled trial, there was a median percent increase in luteinizing hormone of 12% at 6 months and 19% at both 12 and 24 months. Other Effects Plasma lipid panel and bone mineral density were evaluated following 52 weeks of dutasteride 0.5 mg once daily in healthy volunteers. There was no change in bone mineral density as measured by dual energy x-ray absorptiometry compared with either placebo or baseline. In addition, the plasma lipid profile (i.e., total cholesterol, low density lipoproteins, high density lipoproteins, triglycerides) was unaffected by dutasteride. No clinically significant changes in adrenal hormone responses to adrenocorticotropic hormone (ACTH) stimulation were observed in a subset population (n = 13) of the 1-year healthy volunteer trial. 12.3 Pharmacokinetics Absorption Following administration of a single 0.5-mg dose of a capsule, time to peak serum concentrations (T max ) of dutasteride occurs within 2 to 3 hours. Absolute bioavailability in 5 healthy subjects is approximately 60% (range: 40% to 94%). When the drug is administered with food, the maximum serum concentrations were reduced by 10% to 15%. This reduction is of no clinical significance. Distribution Pharmacokinetic data following single and repeat oral doses show that dutasteride has a large volume of distribution (300 to 500 L). Dutasteride is highly bound to plasma albumin (99.0%) and alpha-1 acid glycoprotein (96.6%). In a trial of healthy subjects (n = 26) receiving dutasteride 0.5 mg/day for 12 months, semen dutasteride concentrations averaged 3.4 ng/mL (range: 0.4 to 14 ng/mL) at 12 months and, similar to serum, achieved steady-state concentrations at 6 months. On average, at 12 months 11.5% of serum dutasteride concentrations partitioned into semen. Metabolism and Elimination Dutasteride is extensively metabolized in humans. In vitro studies showed that dutasteride is metabolized by the CYP3A4 and CYP3A5 isoenzymes. Both of these isoenzymes produced the 4′-hydroxydutasteride, 6-hydroxydutasteride, and the 6,4′-dihydroxydutasteride metabolites. In addition, the 15-hydroxydutasteride metabolite was formed by CYP3A4. Dutasteride is not metabolized in vitro by human cytochrome P450 isoenzymes CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP2E1. In human serum following dosing to steady state, unchanged dutasteride, 3 major metabolites (4′-hydroxydutasteride, 1,2-dihydrodutasteride, and 6-hydroxydutasteride), and 2 minor metabolites (6,4′-dihydroxydutasteride and 15-hydroxydutasteride), as assessed by mass spectrometric response, have been detected. The absolute stereochemistry of the hydroxyl additions in the 6 and 15 positions is not known. In vitro , the 4′-hydroxydutasteride and 1,2-dihydrodutasteride metabolites are much less potent than dutasteride against both isoforms of human 5 alpha-reductase. The activity of 6β-hydroxydutasteride is comparable to that of dutasteride. Dutasteride and its metabolites were excreted mainly in feces. As a percent of dose, there was approximately 5% unchanged dutasteride (~1% to ~15%) and 40% as dutasteride-related metabolites (~2% to ~90%). Only trace amounts of unchanged dutasteride were found in urine (<1%). Therefore, on average, the dose unaccounted for approximated 55% (range: 5% to 97%). The terminal elimination half-life of dutasteride is approximately 5 weeks at steady state. The average steady-state serum dutasteride concentration was 40 ng/mL following 0.5 mg/day for 1 year. Following daily dosing, dutasteride serum concentrations achieve 65% of steady-state concentration after 1 month and approximately 90% after 3 months. Due to the long half-life of dutasteride, serum concentrations remain detectable (greater than 0.1 ng/mL) for up to 4 to 6 months after discontinuation of treatment. Specific Populations Pediatric Patients: Dutasteride pharmacokinetics have not been investigated in subjects younger than 18 years. Geriatric Patients: No dose adjustment is necessary in the elderly. The pharmacokinetics and pharmacodynamics of dutasteride were evaluated in 36 healthy male subjects aged between 24 and 87 years following administration of a single 5-mg dose of dutasteride. In this single-dose trial, dutasteride half-life increased with age (approximately 170 hours in men aged 20 to 49 years, approximately 260 hours in men aged 50 to 69 years, and approximately 300 hours in men older than 70 years). Of 2,167 men treated with dutasteride in the 3 pivotal trials, 60% were age 65 and over and 15% were age 75 and over. No overall differences in safety or efficacy were observed between these