Tadalafil

12.1 Mechanism of Action Penile erection during sexual stimulation is caused by increased penile blood flow resulting from the relaxation of penile arteries and corpus cavernosal smooth muscle. This response is mediated by the release of nitric oxide (NO) from nerve terminals and endothelial cells, which stimulates the synthesis of cGMP in smooth muscle cells. Cyclic GMP causes smooth muscle relaxation and increased blood flow into the corpus cavernosum. The inhibition of phosphodiesterase type 5 (PDE5) enhances erectile function by increasing the amount of cGMP. Tadalafil inhibits PDE5. Because sexual stimulation is required to initiate the local release of nitric oxide, the inhibition of PDE5 by tadalafil has no effect in the absence of sexual stimulation. The effect of PDE5 inhibition on cGMP concentration in the corpus cavernosum and pulmonary arteries is also observed in the smooth muscle of the prostate, the bladder and their vascular supply. The mechanism for reducing BPH symptoms has not been established. Studies in vitro have demonstrated that tadalafil is a selective inhibitor of PDE5. PDE5 is found in the smooth muscle of the corpus cavernosum, prostate, and bladder as well as in vascular and visceral smooth muscle, skeletal muscle, urethra, platelets, kidney, lung, cerebellum, heart, liver, testis, seminal vesicle, and pancreas. In vitro studies have shown that the effect of tadalafil is more potent on PDE5 than on other phosphodiesterases. These studies have shown that tadalafil is >10,000-fold more potent for PDE5 than for PDE1, PDE2, PDE4, and PDE7 enzymes, which are found in the heart, brain, blood vessels, liver, leukocytes, skeletal muscle, and other organs. Tadalafil is >10,000-fold more potent for PDE5 than for PDE3, an enzyme found in the heart and blood vessels. Additionally, tadalafil is 700-fold more potent for PDE5 than for PDE6, which is found in the retina and is responsible for phototransduction. Tadalafil is >9,000-fold more potent for P

1 INDICATIONS AND USAGE Tadalafil is a phosphodiesterase 5 (PDE5) inhibitor indicated for the treatment of: erectile dysfunction (ED) ( 1.1 ) the signs and symptoms of benign prostatic hyperplasia (BPH) ( 1.2 ) ED and the signs and symptoms of BPH (ED/BPH) ( 1.3 ) If tadalafil is used with finasteride to initiate BPH treatment, such use is recommended for up to 26 weeks ( 1.4 ). 1.1 Erectile Dysfunction Tadalafil tablets are indicated for the treatment of erectile dysfunction (ED). 1.2 Benign Prostatic Hyperplasia Tadalafil tablets are indicated for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH). 1.3 Erectile Dysfunction and Benign Prostatic Hyperplasia Tadalafil tablets are indicated for the treatment of ED and the signs and symptoms of BPH (ED/BPH). 1.4 Limitation of Use If tadalafil tablets are used with finasteride to initiate BPH treatment, such use is recommended for up to 26 weeks because the incremental benefit of tadalafil tablets decreases from 4 weeks until 26 weeks, and the incremental benefit of tadalafil tablets beyond 26 weeks is unknown [see Clinical Studies ( 14.3 )] .

2 DOSAGE AND ADMINISTRATION Do not split tadalafil tablets; entire dose should be taken. Tadalafil tablets for use as needed: ED: Starting dose: 10 mg as needed prior to sexual activity. Increase to 20 mg or decrease to 5 mg based upon efficacy/tolerability. Improves erectile function compared to placebo up to 36 hours post dose. Not to be taken more than once per day ( 2.1 ). Tadalafil tablets for once daily use: ED: 2.5 mg taken once daily, without regard to timing of sexual activity. May increase to 5 mg based upon efficacy and tolerability ( 2.2 ). BPH: 5 mg, taken at approximately the same time every day ( 2.3 ) ED and BPH: 5 mg, taken at approximately the same time every day ( 2.3 , 2.4 ) Tadalafil tablets may be taken without regard to food ( 2.5 ). 2.1 Tadalafil Tablets for Use as Needed for Erectile Dysfunction The recommended starting dose of tadalafil tablets for use as needed in most patients is 10 mg, taken prior to anticipated sexual activity. The dose may be increased to 20 mg or decreased to 5 mg, based on individual efficacy and tolerability. The maximum recommended dosing frequency is once per day in most patients. Tadalafil tablets for use as needed were shown to improve erectile function compared to placebo up to 36 hours following dosing. Therefore, when advising patients on optimal use of tadalafil tablets, this should be taken into consideration. 2.2 Tadalafil Tablets for Once Daily Use for Erectile Dysfunction The recommended starting dose of tadalafil tablets for once daily use is 2.5 mg, taken at approximately the same time every day, without regard to timing of sexual activity. The tadalafil tablets dose for once daily use may be increased to 5 mg, based on individual efficacy and tolerability. 2.3 Tadalafil Tablets for Once Daily Use for Benign Prostatic Hyperplasia The recommended dose of tadalafil tablets for once daily use is 5 mg, taken at approximately the same time every day. When therapy for BPH is initiated with tadalafil and finasteride, the recommended dose of tadalafil tablets for once daily use is 5 mg, taken at approximately the same time every day for up to 26 weeks. 2.4 Tadalafil Tablets for Once Daily Use for Erectile Dysfunction and Benign Prostatic Hyperplasia The recommended dose of tadalafil tablets for once daily use is 5 mg, taken at approximately the same time every day, without regard to timing of sexual activity. 2.5 Use with Food Tadalafil tablets may be taken without regard to food. 2.6 Use in Specific Populations Renal Impairment Tadalafil Tablets for Use as Needed Creatinine clearance 30 to 50 mL/min: A starting dose of 5 mg not more than once per day is recommended, and the maximum dose is 10 mg not more than once in every 48 hours. Creatinine clearance less than 30 mL/min or on hemodialysis: The maximum dose is 5 mg not more than once in every 72 hours [see Warnings and Precautions ( 5.7 ) and Use in Specific Populations ( 8.7 )] . Tadalafil Tablets for Once Daily Use Erectile Dysfunction Creatinine clearance less than 30 mL/min or on hemodialysis: Tadalafil tablets for once daily use is not recommended [see Warnings and Precautions ( 5.7 ) and Use in Specific Populations ( 8.7 )] . Benign Prostatic Hyperplasia and Erectile Dysfunction/Benign Prostatic Hyperplasia Creatinine clearance 30 to 50 mL/min: A starting dose of 2.5 mg is recommended. An increase to 5 mg may be considered based on individual response. Creatinine clearance less than 30 mL/min or on hemodialysis: Tadalafil tablets for once daily use is not recommended [see Warnings and Precautions ( 5.7 ) and Use in Specific Populations ( 8.7 )] . Hepatic Impairment Tadalafil tablets for Use as Needed Mild or moderate (Child Pugh Class A or B): The dose should not exceed 10 mg once per day. The use of tadalafil tablets once per day has not been extensively evaluated in patients with hepatic impairment and therefore, caution is advised. Severe (Child Pugh Class C): The use of tadalafil tablets is not recommended [see Warnings and Precautions ( 5.8 ) and Use in Specific Populations ( 8.6 )] . Tadalafil tablets for Once Daily Use Mild or moderate (Child Pugh Class A or B): Tadalafil tablets for once daily use has not been extensively evaluated in patients with hepatic impairment. Therefore, caution is advised if tadalafil tablets for once daily use is prescribed to these patients. Severe (Child Pugh Class C): The use of tadalafil tablet is not recommended [see Warnings and Precautions ( 5.8 ) and Use in Specific Populations ( 8.6 )] . 2.7 Concomitant Medications Nitrates Concomitant use of nitrates in any form is contraindicated [see Contraindications ( 4.1 )] . Alpha-Blockers ED —When tadalafil tablets are co-administered with an alpha-blocker in patients being treated for ED, patients should be stable on alpha-blocker therapy prior to initiating treatment, and tadalafil tablets should be initiated at the lowest recommended dose [see Warnings and Precautions ( 5.6 ), Drug Interactions ( 7.1 ), a

6 ADVERSE REACTIONS Most common adverse reactions (≥2%) include headache, dyspepsia, back pain, myalgia, nasal congestion, flushing, and pain in limb ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact VKT Pharma Pvt. Ltd at 1 844-387-1231 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 practice. Tadalafil was administered to over 9000 men during clinical trials worldwide. In trials of tadalafil tablets for once daily use, a total of 1434, 905, and 115 were treated for at least 6 months, 1 year, and 2 years, respectively. For tadalafil tablets for use as needed, over 1300 and 1000 subjects were treated for at least 6 months and 1 year, respectively. Tadalafil Tablets for Use as Needed for ED In eight primary placebo-controlled clinical studies of 12 weeks duration, mean age was 59 years (range 22 to 88) and the discontinuation rate due to adverse events in patients treated with tadalafil 10 or 20 mg was 3.1%, compared to 1.4% in placebo treated patients. When taken as recommended in the placebo-controlled clinical trials, the following adverse reactions were reported ( see Table 1) for tadalafil tablets for use as needed: Table 1: Treatment-Emergent Adverse Reactions Reported by ≥2% of Patients Treated with Tadalafil Tablets (10 or 20 mg) and More Frequent on Drug than Placebo in the Eight Primary Placebo Controlled Clinical Studies (Including a Study in Patients with Diabetes) for Tadalafil Tablets for Use as Needed for ED a The term flushing includes: facial flushing and flushing Adverse Reaction Placebo (N=476) Tadalafil 5 mg (N=151) Tadalafil 10 mg (N=394) Tadalafil 20 mg (N=635) Headache 5% 11% 11% 15% Dyspepsia 1% 4% 8% 10% Back pain 3% 3% 5% 6% Myalgia 1% 1% 4% 3% Nasal congestion 1% 2% 3% 3% Flushing a 1% 2% 3% 3% Pain in limb 1% 1% 3% 3% Tadalafil Tablets for Once Daily Use for ED In three placebo-controlled clinical trials of 12 or 24 weeks duration, mean age was 58 years (range 21 to 82) and the discontinuation rate due to adverse events in patients treated with tadalafil was 4.1%, compared to 2.8% in placebo-treated patients. The following adverse reactions were reported ( see Table 2) in clinical trials of 12 weeks duration: Table 2: Treatment-Emergent Adverse Reactions Reported by ≥2% of Patients Treated with Tadalafil Tablets for Once Daily Use (2.5 or 5 mg) and More Frequent on Drug than Placebo in the Three Primary Placebo-Controlled Phase 3 Studies of 12 weeks Treatment Duration (Including a Study in Patients with Diabetes) for Tadalafil Tablets for Once Daily Use for ED Adverse Reaction Placebo (N=248) Tadalafil 2.5 mg (N=196) Tadalafil 5 mg (N=304) Headache 5% 3% 6% Dyspepsia 2% 4% 5% Nasopharyngitis 4% 4% 3% Back pain 1% 3% 3% Upper respiratory tract infection 1% 3% 3% Flushing 1% 1% 3% Myalgia 1% 2% 2% Cough 0% 4% 2% Diarrhea 0% 1% 2% Nasal congestion 0% 2% 2% Pain in extremity 0% 1% 2% Urinary tract infection 0% 2% 0% Gastroesophageal reflux disease 0% 2% 1% Abdominal pain 0% 2% 1% The following adverse reactions were reported ( see Table 3) over 24 weeks treatment duration in one placebo-controlled clinical study: Table 3: Treatment-Emergent Adverse Reactions Reported by ≥2% of Patients Treated with Tadalafil Tablets for Once Daily Use (2.5 or 5 mg) and More Frequent on Drug than Placebo in One Placebo-Controlled Clinical Study of 24 Weeks Treatment Duration for Tadalafil Tablets for Once Daily Use for ED Adverse Reaction Placebo (N=94) Tadalafil 2.5 mg (N=96) Tadalafil 5 mg (N=97) Nasopharyngitis 5% 6% 6% Gastroenteritis 2% 3% 5% Back pain 3% 5% 2% Upper respiratory tract infection 0% 3% 4% Dyspepsia 1% 4% 1% Gastroesophageal reflux disease 0% 3% 2% Myalgia 2% 4% 1% Hypertension 0% 1% 3% Nasal congestion 0% 0% 4% Tadalafil Tablets for Once Daily Use for BPH and for ED and BPH In three placebo-controlled clinical trials of 12 weeks duration, two in patients with BPH and one in patients with ED and BPH, the mean age was 63 years (range 44 to 93) and the discontinuation rate due to adverse events in patients treated with tadalafil was 3.6% compared to 1.6% in placebo-treated patients. Adverse reactions leading to discontinuation reported by at least 2 patients treated with tadalafil included headache, upper abdominal pain, and myalgia. The following adverse reactions were reported ( see Table 4). Table 4: Treatment-Emergent Adverse Reactions Reported by ≥1% of Patients Treated with Tadalafil Tablets for Once Daily Use (5 mg) and More Frequent on Drug than Placebo in Three Placebo-Controlled Clinical Studies of 12 Weeks Treatment Duration, including Two Studies for Tadalafil Tablets for Once Daily Use for BPH and One Study for ED and BPH Adverse Reaction Placebo (N=576) Tadalafil 5 mg (N=581) Headache

7 DRUG INTERACTIONS Tadalafil tablets can potentiate the hypotensive effects of nitrates, alpha-blockers, antihypertensives or alcohol ( 7.1 ). CYP3A4 inhibitors (e.g. ketoconazole, ritonavir) increase tadalafil exposure ( 2.7 , 5.10 , 7.2 ) requiring dose adjustment: Tadalafil tablets for use as needed: no more than 10 mg every 72 hours Tadalafil tablets for once daily use: dose not to exceed 2.5 mg CYP3A4 inducers (e.g. rifampin) decrease tadalafil exposure ( 7.2 ). 7.1 Potential for Pharmacodynamic Interactions with Tadalafil Tablets Nitrates — Administration of tadalafil tablets to patients who are using any form of organic nitrate, is contraindicated. In clinical pharmacology studies, tadalafil was shown to potentiate the hypotensive effect of nitrates. In a patient who has taken tadalafil tablets, where nitrate administration is deemed medically necessary in a life-threatening situation, at least 48 hours should elapse after the last dose of tadalafil tablets before nitrate administration is considered. In such circumstances, nitrates should still only be administered under close medical supervision with appropriate hemodynamic monitoring [see Dosage and Administration ( 2.7 ), Contraindications ( 4.1 ), and Clinical Pharmacology ( 12.2 )] . Alpha-Blockers — Caution is advised when PDE5 inhibitors are coadministered with alpha-blockers. PDE5 inhibitors, including tadalafil, and alpha-adrenergic blocking agents are both vasodilators with blood-pressure-lowering effects. When vasodilators are used in combination, an additive effect on blood pressure may be anticipated. Clinical pharmacology studies have been conducted with coadministration of tadalafil with doxazosin, tamsulosin or alfuzosin. [see Dosage and Administration ( 2.7 ), Warnings and Precautions ( 5.6 ), and Clinical Pharmacology ( 12.2 )] . Antihypertensives — PDE5 inhibitors, including tadalafil, are mild systemic vasodilators. Clinical pharmacology studies were conducted to assess the effect of tadalafil on the potentiation of the blood-pressure-lowering effects of selected antihypertensive medications (amlodipine, angiotensin II receptor blockers, bendrofluazide, enalapril, and metoprolol). Small reductions in blood pressure occurred following coadministration of tadalafil with these agents compared with placebo. [see Warnings and Precautions ( 5.6 ) and Clinical Pharmacology ( 12.2 )] . Alcohol — Both alcohol and tadalafil, a PDE5 inhibitor, act as mild vasodilators. When mild vasodilators are taken in combination, blood-pressure-lowering effects of each individual compound may be increased. Substantial consumption of alcohol (e.g., 5 units or greater) in combination with tadalafil tablets can increase the potential for orthostatic signs and symptoms, including increase in heart rate, decrease in standing blood pressure, dizziness, and headache. Tadalafil did not affect alcohol plasma concentrations and alcohol did not affect tadalafil plasma concentrations. [see Warnings and Precautions ( 5.9 ) and Clinical Pharmacology ( 12.2 )] . 7.2 Potential for Other Drugs to Affect Tadalafil Tablets [See Dosage and Administration ( 2.7 ) and Warnings and Precautions ( 5.10 )] . Antacids — Simultaneous administration of an antacid (magnesium hydroxide/aluminum hydroxide) and tadalafil reduced the apparent rate of absorption of tadalafil without altering exposure (AUC) to tadalafil. H 2 Antagonists (e.g. Nizatidine) — An increase in gastric pH resulting from administration of nizatidine had no significant effect on pharmacokinetics. Cytochrome P450 Inhibitors — Tadalafil is a substrate of and predominantly metabolized by CYP3A4. Studies have shown that drugs that inhibit CYP3A4 can increase tadalafil exposure. CYP3A4 (e.g., Ketoconazole) — Ketoconazole (400 mg daily), a selective and potent inhibitor of CYP3A4, increased tadalafil 20 mg single-dose exposure (AUC) by 312% and C max by 22%, relative to the values for tadalafil 20 mg alone. Ketoconazole (200 mg daily) increased tadalafil 10-mg single-dose exposure (AUC) by 107% and C max by 15%, relative to the values for tadalafil 10 mg alone [see Dosage and Administration ( 2.7 )] . Although specific interactions have not been studied, other CYP3A4 inhibitors, such as erythromycin, itraconazole, and grapefruit juice, would likely increase tadalafil exposure. HIV Protease inhibitor — Ritonavir (500 mg or 600 mg twice daily at steady state), an inhibitor of CYP3A4, CYP2C9, CYP2C19, and CYP2D6, increased tadalafil 20-mg single-dose exposure (AUC) by 32% with a 30% reduction in C max , relative to the values for tadalafil 20 mg alone. Ritonavir (200 mg twice daily), increased tadalafil 20-mg single-dose exposure (AUC) by 124% with no change in C max , relative to the values for tadalafil 20 mg alone. Although specific interactions have not been studied, other HIV protease inhibitors would likely increase tadalafil exposure [see Dosage and Administration ( 2.7 )] . Cytochrome P450 Inducers — Studies have