Finasteride

1 INDICATIONS AND USAGE Finasteride, is a 5α-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 Reduce the risk of the need for surgery including transurethral resection of the prostate (TURP) and prostatectomy. Finasteride administered in combination with the alpha-blocker doxazosin is indicated to reduce the risk of symptomatic progression of BPH (a confirmed ≥4 point increase in American Urological Association (AUA) symptom score) (1.2). Limitations of Use : Finasteride is not approved for the prevention of prostate cancer (1.3). 1.1 Monotherapy Finasteride tablets 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 - Reduce the risk of the need for surgery including transurethral resection of the prostate (TURP) and prostatectomy. 1.2 Combination with Alpha-Blocker Finasteride tablets administered in combination with the alpha-blocker doxazosin are indicated to reduce the risk of symptomatic progression of BPH (a confirmed ≥4 point increase in American Urological Association (AUA) symptom score). 1.3 Limitations of Use Finasteride tablets are not approved for the prevention of prostate cancer.

2 DOSAGE AND ADMINISTRATION Finasteride tablets may be administered with or without meals. Finasteride may be administered with or without meals (2). Monotherapy: One tablet (5 mg) taken once a day (2.1). Combination with Doxazosin: One tablet (5 mg) taken once a day in combination with the alpha-blocker doxazosin (2.2). 2.1 Monotherapy The recommended dose of finasteride tablets is one tablet (5 mg) taken once a day [see Clinical Studies (14.1) ]. 2.2 Combination with Alpha-Blocker The recommended dose of finasteride is one tablet (5 mg) taken once a day in combination with the alpha-blocker doxazosin [see Clinical Studies (14.2) ].

3 DOSAGE FORMS AND STRENGTHS Finasteride tablets are reddish brown colored, 7 mm round, biconvex, film coated tablets, marked “F1” on one side and plain on other side. 1 mg tablets (3).

4 CONTRAINDICATIONS Finasteride tablets are contraindicated in the following: Hypersensitivity to any component of this medication. Pregnancy. Finasteride use is contraindicated in females when they are or may potentially be pregnant. Because of the ability of Type II 5α-reductase inhibitors to inhibit the conversion of testosterone to 5α-dihydrotestosterone (DHT), finasteride may cause abnormalities of the external genitalia of a male fetus of a pregnant females who receives finasteride. If this drug is used during pregnancy, or if pregnancy occurs while taking this drug, the pregnant females should be apprised of the potential hazard to the male fetus. [ See also Warnings and Precautions (5.3) , Use in Specific Populations (8.1) , and How Supplied/Storage and Handling (16) ]. In female rats, low doses of finasteride administered during pregnancy have produced abnormalities of the external genitalia in male offspring. Hypersensitivity to any components of this product ( 4 ). Females who are or may potentially be pregnant ( 4 , 5.3 , 8.1 , 16 ).

6 ADVERSE REACTIONS The drug-related adverse reactions, reported in ≥1% in patients treated with finasteride and greater than in patients treated with placebo over a 4 year study are: impotence, decreased libido, decreased volume of ejaculate, breast enlargement, breast tenderness and rash (6.1). To report SUSPECTED ADVERSE REACTIONS, contact Dr. Reddy’s Laboratories Inc. at 1-888-375-3784 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 to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. 4-Year Placebo-Controlled Study (Long-Term Efficacy and Safety Study) In a long-term efficacy and safety study, 1524 patients treated with finasteride and 1516 patients treated with placebo were evaluated for safety over a period of 4 years. The most frequently reported adverse reactions were related to sexual function. 3.7% (57 patients) treated with finasteride and 2.1% (32 patients) treated with placebo discontinued therapy as a result of adverse reactions related to sexual function, which are the most frequently reported adverse reactions. Table 1 presents the only clinical adverse reactions considered possibly, probably or definitely drug related by the investigator, for which the incidence on finasteride was ≥1% and greater than placebo over the 4 years of the study. In years 2 to 4 of the study, there was no significant difference between treatment groups in the incidences of impotence, decreased libido and ejaculation disorder. Table 1: Drug-Related Adverse Experiences Year 1 (%) Years 2, 3 and 4* (%) Finasteride Placebo Finasteride Placebo Impotence 8.1 3.7 5.1 5.1 Decreased Libido 6.4 3.4 2.6 2.6 Decreased Volume of Ejaculate 3.7 0.8 1.5 0.5 Ejaculation Disorder 0.8 0.1 0.2 0.1 Breast Enlargement 0.5 0.1 1.8 1.1 Breast Tenderness 0.4 0.1 0.7 0.3 Rash 0.5 0.2 0.5 0.1 *Combined Years 2 to 4 N = 1524 and 1516, finasteride vs placebo, respectively Phase III Studies and 5-Year Open Extensions The adverse experience profile in the 1-year, placebo-controlled, Phase III studies, the 5 year open extensions, and PLESS were similar. The adverse experience profile in the 1-year, placebo-controlled, Phase III studies, the 5-year open extensions, and thelong-term efficacy and safety study were similar. Medical Therapy of Prostatic Symptoms (MTOPS) Study In the MTOPS study, 3047 men with symptomatic BPH were randomized to receive finasteride 5 mg/day (n=768), doxazosin 4 or 8 mg/day (n=756), the combination of finasteride 5 mg/day and doxazosin 4 or 8 mg/day (n=786), or placebo (n=737) for 4 to 6 years. [ See Clinical Studies (14.2) . ] The incidence rates of drug-related adverse experiences reported by ≥2% of patients in any treatment group in the MTOPS Study are listed in Table 2. The individual adverse effects which occurred more frequently in the combination group compared to either drug alone were: asthenia, postural hypotension, peripheral edema, dizziness, decreased libido, rhinitis, abnormal ejaculation, impotence and abnormal sexual function (see Table 2). Of these, the incidence of abnormal ejaculation in patients receiving combination therapy was comparable to the sum of the incidences of this adverse experience reported for the two monotherapies. Combination therapy with finasteride and doxazosin was associated with no new clinical adverse experience. Four patients in MTOPS reported the adverse experience breast cancer. Three of these patients were on finasteride only and one was on combination therapy. [See Long-Term Data.] The MTOPS Study was not specifically designed to make statistical comparisons between groups for reported adverse experiences. In addition, direct comparisons of safety data between the MTOPS study and previous studies of the single agents may not be appropriate base …

7 DRUG INTERACTIONS 7.1 Cytochrome P450-Linked Drug Metabolizing Enzyme System No drug interactions of clinical importance have been identified. Finasteride does not appear to affect the cytochrome P450-linked drug-metabolizing enzyme system. Compounds that have been tested in man include antipyrine, digoxin, propranolol, theophylline, and warfarin and no clinically meaningful interactions were found. 7.2 Other Concomitant Therapy Although specific interaction studies were not performed, finasteride doses of 1 mg or more were concomitantly used in clinical studies with acetaminophen, acetylsalicylic acid, α-blockers, analgesics, angiotensin-converting enzyme (ACE) inhibitors, anticonvulsants, benzodiazepines, beta blockers, calcium-channel blockers, cardiac nitrates, diuretics, H antagonists, HMG-CoA reductase 2 inhibitors, prostaglandin synthetase inhibitors (also referred to as NSAIDs), and quinolone anti-infectives without evidence of clinically significant adverse interactions.

8 USE IN SPECIFIC POPULATIONS 8.1 Pregnancy Risk Summary Finasteride is contraindicated in pregnant females and not indicated for use in females. Based onanimal studies and the mechanism of action, Finasteride may cause abnormal development of external genitalia in a male fetus if administered to a pregnant female [ see Warnings and Precautions ( 5.3 ) andClinical Pharmacology ( 12.1 ) ]. In an embryo-fetal development study in rats, there was a dose-dependent increase in hypospadias that occurred in 3.6 to 100% of male offspring of pregnant rats administered oral finasteride during the period of major organogenesis at doses approximately 0.1 to 86 times the maximum recommended human dose (MRHD) of 5 mg/day (based on AUC at animal doses of 0.1 to 100 mg/kg/day). Decreased prostatic and seminal vesicular weights, delayed preputial separation and transient nipple development were also observed in male offspring at oral maternal doses approximately 0.03 times the MRHD (based on AUC at animal dose of 0.03 mg/kg/day), along with decreased anogenital distance in male offspring at oral maternal doses approximately 0.003 times the MRHD (based on AUC at animal dose of 0.003 mg/kg/day). Finasteride is a Type II 5α-reductase inhibitor that prevents conversion of testosterone to 5α-dihydrotestosterone (DHT), a hormone necessary for normal development of male genitalia. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the male fetus. Abnormal male genital development is an expected consequence when conversion of testosterone to 5α-dihydrotestosterone (DHT) is inhibited by 5α-reductase inhibitors. These outcomes are similar to those reported in male infants with genetic 5α-reductase deficiency. Females could be exposed to finasteride through contact with crushed or broken finasteride tablets or semen from a male partner taking finasteride. With regard to finasteride exposure through the skin, finasteride tablets are coated and will prevent skin contact with finasteride during normal handling if the tablets have not been crushed or broken. Females who are pregnant or may potentially be pregnant should not handle crushed or broken finasteride tablets because of possible exposure of a male fetus. With regard to potential finasteride exposure through semen, three studies have been conducted that measured finasteride concentrations in semen in men receiving finasteride 5 mg/day. In these studies the highest amount of finasteride in semen was estimated to be 50- to 100-fold less than the dose of finasteride (5 mcg) that had no effect on circulating DHT levels in men [ see Data and Clinical Pharmacology ( 12.3 ) ]. Data Human Data In 2 studies of healthy subjects (n=69) receiving finasteride 5 mg/day for 6 to 24 weeks, finasteride concentrations in semen ranged from undetectable (<0.1 ng/mL) to 10.54 ng/mL. In an earlier study using a less sensitive assay, finasteride concentrations in semen of 16 subjects receiving finasteride 5 mg/day ranged from undetectable (<1 ng/mL) to 21 ng/mL. Using the highest semen level measured and assuming 100% absorption would be up to 105 ng per day, which is 50- to 100-fold less than the dose of finasteride (5 mcg) that had no effect on circulating DHT levels in men [see Clinical Pharmacology (12.3)]. Animal Data In an embryo-fetal development study, pregnant rats received finasteride during the period of major organogenesis (gestation days 6 to 17). At maternal doses of oral finasteride approximately 0.1 to 86 times the maximum recommended human dose (MRHD) of 5 mg/day (based on AUC at animal doses of 0.1 to 100 mg/kg/day) there was a dose-dependent increase in hypospadias that occurred in 3.6 to 100% of male offspring. Exposure multiples were estimated using data from nonpregnant rats. Days 16 to 17 of gestation is a critical period in male fetal rats for differentiation of the external genitalia. At oral ma …

12.1 Mechanism of Action Finasteride is a competitive and specific inhibitor of Type II 5α-reductase, an intracellular enzyme that converts the androgen testosterone into DHT. Two distinct isozymes are found in mice, rats, monkeys, and humans: Type I and II. Each of these isozymes is differentially expressed in tissues and developmental stages. In humans, Type I 5 α-reductase is predominant in the sebaceous glands of most regions of skin, including scalp, and liver. Type I 5 α-reductase is responsible for approximately onethird of circulating DHT. The Type II 5 α-reductase isozyme is primarily found in prostate, seminal vesicles, epididymides, and hair follicles as well as liver, and is responsible for two-thirds of circulating DHT. In humans, the mechanism of action of finasteride is based on its preferential inhibition of the Type II isozyme. Using native tissues (scalp and prostate), in vitro binding studies examining the potential of finasteride to inhibit either isozyme revealed a 100-fold selectivity for the human Type II 5 α-reductase over Type I isozyme (IC =500 and 4.2 nM for Type I and II, respectively). For both isozymes, the 50 inhibition by finasteride is accompanied by reduction of the inhibitor to dihydrofinasteride and adduct formation with NADP+. The turnover for the enzyme complex is slow (t approximately 30 days for the 1/2 Type II enzyme complex and 14 days for the Type I complex). Inhibition of Type II 5 α-reductase blocks the peripheral conversion of testosterone to DHT, resulting in significant decreases in serum and tissue DHT concentrations. In men with male pattern hair loss (androgenetic alopecia), the balding scalp contains miniaturized hair follicles and increased amounts of DHT compared with hairy scalp. Administration of finasteride decreases scalp and serum DHT concentrations in these men. The relative contributions of these reductions to the treatment effect of finasteride have not been defined. By this mechanism, finasteride appears to interrupt a key factor in the development of androgenetic alopecia in those patients genetically predisposed.

11 DESCRIPTION Finasteride tablets contain finasteride as the active ingredient. Finasteride, a synthetic 4-azasteroid compound, is a specific inhibitor of steroid Type II 5α-reductase, an intracellular enzyme that converts the androgen testosterone into 5α-dihydrotestosterone (DHT). The chemical name of finasteride is N-tert -Butyl-3-oxo-4-aza-5α-androst-1-ene-17β-carboxamide. The empirical formula of finasteride is C 23 H 36 N 2 O 2 and its molecular weight is 372.55. Its structural formula is: Finasteride is a white crystalline powder with a melting point near 250°C. It is freely soluble in chloroform and in lower alcohol solvents but is practically insoluble in water. Finasteride Tablets, USP are film-coated tablets for oral administration. Each tablet contains 1 mg of finasteride and the following inactive ingredients: lactose monohydrate, microcrystalline cellulose, pregelatinized starch, sodium starch glycolate, lauroylmacrogol 32 glycerides, magnesium stearate, Hypromellose, Titanium Dioxide, polyethylene glycol, Iron Oxide Red, and Iron Oxide Yellow. finasteride-stru1.jpg

10 OVERDOSAGE In clinical studies, single doses of finasteride up to 400 mg and multiple doses of finasteride up to 80 mg/day for three months did not result in adverse reactions. Until further experience is obtained, no specific treatment for an overdose with finasteride can be recommended. Significant lethality was observed in male and female mice at single oral doses of 1500 mg/m 2 (500 mg/kg) and in female and male rats at single oral doses of 2360 mg/m 2 (400 mg/kg) and 5900 mg/m 2 (1000 mg/kg), respectively.

16 HOW SUPPLIED/STORAGE AND HANDLING Finasteride tablets, USP 1 mg are available as reddish brown colored, 7 mm round, biconvex, film coated tablets, marked “F1” on one side and plain on other side. They are supplied as follows: 90's HDPE Container pack: NDC 71713-099-90 Storage and Handling Store at 20o to 25oC (68o to 77oF) [See USP Controlled Room Temperature]. Preserve in a tight, light resistant container Women should not handle crushed or broken finasteride Tablets when they are pregnant or may potentially be pregnant because of the possibility of absorption of finasteride and the subsequent potential risk to a male fetus. Finasteride Tablets, USP 1 mg are coated and will prevent contact with the active ingredient during normal handling, provided that the tablets are not broken or crushed [see Warnings and Precautions (5.1), Use in Specific Populations (8.1) and Patient Counseling Information (17.1)].