Dutasteride

1 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.

2 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.

5 WARNINGS AND PRECAUTIONS Dutasteride capsules reduce serum prostate-specific antigen (PSA) concentration by approximately 50%. However, any confirmed increase in PSA while on dutasteride 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. ( 5.1 ) Dutasteride capsules may increase the risk of high-grade prostate cancer. ( 5.2 , 6.1 ) Prior to initiating treatment with dutasteride capsules, consideration should be given to other urological conditions that may cause similar symptoms. ( 5.3 ) Women who are pregnant or may be pregnant should not handle dutasteride capsules due to potential risk to a male fetus. ( 5.4 , 8.1 ) Patients should not donate blood until 6 months after their last dose of dutasteride capsules. (5.5) 5.1 Effects on Prostate-specific Antigen (PSA) and the Use of PSA in Prostate Cancer Detection 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 subjects with symptomatic BPH, although it may vary in individuals. dutasteride may also cause decreases in serum PSA in the presence of prostate cancer. To interpret serial PSAs in men taking dutasteride, a new PSA baseline 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 dutasteride 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 may also affect PSA test results. To interpret an isolated PSA value in a man treated with dutasteride 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, no adjustment to its value appears necessary. Coadministration of dutasteride and tamsulosin resulted in similar changes to serum PSA as dutasteride monotherapy. 5.2 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 8-10 prostate cancer compared with men taking placebo (dutasteride 1.0% versus placebo 0.5%) [see Indications and Usage (1.3) , 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 8-10 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. 5.3 Evaluation for Other Urological Diseases Prior to initiating treatment with dutasteride, consideration should be given to other urological conditions that may cause similar symptoms. In addition, BPH and prostate cancer may coexist. 5.4 Transdermal Exposure of Dutasteride in Pregnant Women—Risk to Male Fetus Dutasteride capsules should not be handled by women who are pregnant or may be pregnant. Dutasteride can be absorbed through the skin and could result in unintended fetal exposure and potential risk to a male fetus. If a pregnant woman comes in contact with leaking dutasteride capsules, the contact area should be washed immediately with soap and water [see Use in Specific Populations (8.1) ]. Dut…

4 CONTRAINDICATIONS Dutasteride capsules are contraindicated for use in: Pregnancy. Dutasteride use is contraindicated in women who are pregnant. 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. [see Warnings and Precautions (5.4) , Use in Specific Populations (8.1) ]. 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. Dutasteride use is contraindicated in women who are pregnant. ( 4 , 5.4 , 8.1 ) Patients with previously demonstrated, clinically significant hypersensitivity (e.g., serious skin reactions, angioedema) to dutasteride capsules or other 5 alpha-reductase inhibitors. ( 4 )

7 DRUG INTERACTIONS Use with caution in patients taking potent, chronic cytochrome P450 (CYP)3A4 enzyme inhibitors (e.g., ritonavir). ( 7 ) 7.1 Cytochrome P450 3A Inhibitors Dutasteride is extensively metabolized in humans by the CYP3A4 and CYP3A5 isoenzymes. The effect of potent CYP3A4 inhibitors on dutasteride has not been studied. Because of the potential for drug-drug interactions, use caution when prescribing dutasteride capsules to patients taking potent, chronic CYP3A4 enzyme inhibitors (e.g., ritonavir) [see Clinical Pharmacology (12.3) ]. 7.2 Alpha-adrenergic Antagonists The administration of dutasteride capsules in combination with tamsulosin or terazosin has no effect on the steady-state pharmacokinetics of either alpha-adrenergic antagonist. The effect of administration of tamsulosin or terazosin on dutasteride pharmacokinetic parameters has not been evaluated. 7.3 Calcium Channel Antagonists Coadministration of verapamil or diltiazem decreases dutasteride clearance and leads to increased exposure to dutasteride. The change in dutasteride exposure is not considered to be clinically significant. No dose adjustment is recommended [see Clinical Pharmacology (12.3) ]. 7.4 Cholestyramine Administration of a single 5-mg dose of dutasteride capsules followed 1 hour later by 12 g of cholestyramine does not affect the relative bioavailability of dutasteride [see Clinical Pharmacology (12.3) ]. 7.5 Digoxin Dutasteride capsules do not alter the steady-state pharmacokinetics of digoxin when administered concomitantly at a dose of 0.5 mg/day for 3 weeks [see Clinical Pharmacology (12.3) ]. 7.6 Warfarin Concomitant administration of dutasteride capsules 0.5 mg/day for 3 weeks with warfarin does not alter the steady-state pharmacokinetics of the S- or R-warfarin isomers or alter the effect of warfarin on prothrombin time [see Clinical Pharmacology (12.3) ].

8.1 Pregnancy Risk Summary Dutasteride is contraindicated for use in pregnancy because it may cause harm to the male fetus [see Contraindications (4) ]. Dutasteride is not indicated for use in women. Dutasteridem is a 5 alpha-reductase inhibitor that prevents conversion of testosterone to dihydrotestosterone (DHT), a hormone necessary for normal development of male genitalia. Abnormalities in the genitalia of male fetuses is an expected physiological consequence of inhibition of this conversion. These results are similar to observations in male infants with genetic 5 alpha-reductase deficiency. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. In animal reproduction studies, dutasteride inhibited normal development of external genitalia in male offspring when given to rats or rabbits during organogenesis at less than the maximum recommended human dose (MRHD) of 0.5 mg daily, in the absence of maternal toxicity. At 15 times the MRHD, prolonged pregnancy, decreased reproductive organ weights, and delayed puberty in male offspring were observed in rats, with no-effect levels less than the MRHD of 0.5 mg daily. Increased placental weights in rabbits were also observed, with no-effect levels less than the MRHD of 0.5 mg daily (see Data). Although dutasteride is secreted into human semen, the drug concentration in the human female partner is approximately 100 times less than concentrations producing abnormalities of male genitalia in animal studies (see Data). In monkeys dosed during organogenesis at blood concentrations comparable to or above levels to which a human female partner is estimated to be exposed, male offspring external genitalia was not adversely affected. No feminization occurred in male offspring of untreated female rats mated to treated male rats even though detectable blood levels of dutasteride were observed in the female rats [see Nonclinical Toxicology (13.1) ]. Data Human Data: The highest measured semen concentration of dutasteride in treated men was 14 ng/mL. Although dutasteride is detected in semen, assuming exposure of a 50-kg woman to 5 mL of semen and 100% absorption, the woman’s expected dutasteride blood concentration through semen would be about 0.0175 ng/mL. This concentration is approximately 100 times less than blood concentrations producing abnormalities of male genitalia in animal studies. Dutasteride is highly protein bound in human semen (greater than 96%), which may reduce the amount of dutasteride available for vaginal absorption. Animal Data: In an embryo-fetal development study in rats, oral administration of dutasteride at 10 times less than the MRHD of 0.5 mg daily (based on average blood levels in men) resulted in feminization of male genitalia in the fetus (decreased anogenital distance at 0.05 mg/kg/day, with a lack of a no-effect level) in the absence of maternal toxicity. In addition, nipple development, hypospadias, and distended preputial glands occurred in fetuses of dams treated at doses of 2.5 mg/kg/day or greater (approximately 15 times the MRHD). Reduced fetal body weight and associated delayed ossification in the presence of maternal toxicity (decreased body weight gain) were observed at maternal exposure approximately 15 times the MRHD (dose of 2.5 mg/kg/day or greater). An increase in stillborn pups was observed in dams treated at 30 mg/kg/day (approximately 111 times the MRHD), with a no-effect level of 12.5 mg/kg/day. In a rabbit embryo-fetal development study, doses 28 times the MRHD (doses of 30 mg/kg/day or greater), based on average blood levels in men, were administered orally on Gestation Days 7 to 29 (during organogenesis and the late period of external genitalia development). Histological evaluation of the genital papilla of fetuses revealed evidence of feminization of the male fetus as well as fused skull bones and increased placental …

6 ADVERSE REACTIONS The most common adverse reactions, reported in ≥1% of subjects treated with dutasteride capsules and more commonly than in subjects treated with placebo, are impotence, decreased libido, ejaculation disorders, and breast disorders. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Epic Pharma, LLC at 1-888-374-2791 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 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 with rates in the clinical trial of another drug and may not reflect the rates observed in practice. From clinical trials with Dutasteride as monotherapy or in combination with tamsulosin: The most common adverse reactions reported in subjects receiving dutasteride were impotence, decreased libido, breast disorders (including breast enlargement and tenderness), and ejaculation disorders. The most common adverse reactions reported in subjects receiving combination therapy (dutasteride plus tamsulosin) were impotence, decreased libido, breast disorders (including breast enlargement and tenderness), ejaculation disorders, and dizziness. Ejaculation disorders occurred significantly more in subjects receiving combination therapy (11%) compared with those receiving dutasteride (2%) or tamsulosin (4%) as monotherapy. Trial withdrawal due to adverse reactions occurred in 4% of subjects receiving dutasteride, and 3% of subjects receiving placebo in placebo-controlled trials with dutasteride. The most common adverse reaction leading to trial withdrawal was impotence (1%). In the clinical trial evaluating the combination therapy, trial withdrawal due to adverse reactions occurred in 6% of subjects receiving combination therapy (dutasteride plus tamsulosin) and 4% of subjects receiving dutasteride or tamsulosin as monotherapy. The most common adverse reaction in all treatment arms leading to trial withdrawal was erectile dysfunction (1% to 1.5%). Monotherapy Over 4,300 male subjects with BPH were randomly assigned to receive placebo or 0.5-mg daily doses of dutasteride in 3 identical 2-year, placebo-controlled, double-blind, Phase 3 treatment trials, each followed by a 2-year open-label extension. During the double-blind treatment period, 2,167 male subjects were exposed to dutasteride, including 1,772 exposed for 1 year and 1,510 exposed for 2 years. When including the open-label extensions, 1,009 male subjects were exposed to dutasteride for 3 years and 812 were exposed for 4 years. The population was aged 47 to 94 years (mean age: 66 years) and greater than 90% were white. Table 1 summarizes clinical adverse reactions reported in at least 1% of subjects receiving dutasteride and at a higher incidence than subjects receiving placebo. Table 1. Adverse Reactions Reported in ≥1% of Subjects over a 24-Month Period and More Frequently in the Group Receiving Dutasteride Capsules than the Placebo Group (Randomized, Double-blind, Placebo-Controlled Trials Pooled) by Time of Onset Adverse Reaction Adverse Reaction Time of Onset Months 0-6 Months 7-12 Months 13-18 Months 19-24 Dutasteride capsules (n) (n = 2,167) (n = 1,901) (n = 1,725) (n = 1,605) Placebo (n) (n = 2,158) (n = 1,922) (n = 1,714) (n = 1,555) Impotencea Dutasteride capsules 4.7% 1.4% 1.0% 0.8% Placebo 1.7% 1.5% 0.5% 0.9% Decreased libido a Dutasteride capsules 3.0% 0.7% 0.3% 0.3% Placebo 1.4% 0.6% 0.2% 0.1% Ejaculation disorders a Dutasteride capsules 1.4% 0.5% 0.5% 0.1% Placebo 0.5% 0.3% 0.1% 0.0% Breast disorders b Dutasteride capsules 0.5% 0.8% 1.1% 0.6% Placebo 0.2% 0.3% 0.3% 0.1% a These sexual adverse reactions are associated with dutasteride treatment (including monotherapy and combination with tamsulosin). These adverse reactions may persist after treatment discontinuation. The role of dutasteride in this persistence is unknown. b Includes breast tenderness and breast enlargement. Long-Term Treatme…