Sildenafil

1 INDICATIONS AND USAGE VIAGRA is indicated for the treatment of erectile dysfunction. VIAGRA is a phosphodiesterase-5 (PDE5) inhibitor indicated for the treatment of erectile dysfunction (ED)

2 DOSAGE AND ADMINISTRATION • For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity • Based on effectiveness and toleration, may increase to a maximum of 100 mg or decrease to 25 mg • Maximum recommended dosing frequency is once per day

2.1Dosage Information For

most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity. The maximum recommended dosing frequency is once per day. Based on effectiveness and toleration, the dose may be increased to a maximum recommended dose of 100 mg or decreased to 25 mg.

2.2Use with Food

VIAGRA may be taken with or without food.

2.3Dosage Adjustments in Specific Situations

VIAGRA was shown to potentiate the hypotensive effects of nitrates and its administration in patients who use nitric oxide donors such as organic nitrates or organic nitrites in any form is therefore contraindicated . When VIAGRA is co-administered with an alpha-blocker, patients should be stable on alpha-blocker therapy prior to initiating VIAGRA treatment and VIAGRA should be initiated at 25 mg .

2.4Dosage Adjustments Due to Drug Interactions

Ritonavir The recommended dose for ritonavir-treated patients is 25 mg prior to sexual activity and the recommended maximum dose is 25 mg within a 48 hour period because concomitant administration increased the blood levels of sildenafil by 11-fold . CYP3A4 Inhibitors Consider a starting dose of 25 mg in patients treated with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, or saquinavir) or erythromycin. Clinical data have shown that co-administration with saquinavir or erythromycin increased plasma levels of sildenafil by about 3 fold .

2.5Dosage Adjustments in Special Populations Consider

a starting dose of 25 mg in patients > 65 years, patients with hepatic impairment (e.g., cirrhosis), and patients with severe renal impairment (creatinine clearance <30 mL/minute) because administration of VIAGRA in these patients resulted in higher plasma levels of sildenafil .

5 WARNINGS AND PRECAUTIONS • Patients should not use VIAGRA if sexual activity is inadvisable due to cardiovascular status • Patients should seek emergency treatment if an erection lasts >4 hours. Use VIAGRA with caution in patients predisposed to priapism • Patients should stop VIAGRA and seek medical care if a sudden loss of vision occurs in one or both eyes, which could be a sign of non arteritic anterior ischemic optic neuropathy (NAION). VIAGRA should be used with caution, and only when the anticipated benefits outweigh the risks, in patients with a history of NAION. Patients with a “crowded” optic disc may also be at an increased risk of NAION. • Patients should stop VIAGRA and seek prompt medical attention in the event of sudden decrease or loss of hearing • Caution is advised when VIAGRA is co-administered with alpha-blockers or anti-hypertensives. Concomitant use may lead to hypotension • Decreased blood pressure, syncope, and prolonged erection may occur at higher sildenafil exposures. In patients taking strong CYP inhibitors, such as ritonavir, sildenafil exposure is increased. Decrease in VIAGRA dosage is recommended ( 2.4 , 5.6 )

5.1Cardiovascular There

is a potential for cardiac risk of sexual activity in patients with preexisting cardiovascular disease. Therefore, treatments for erectile dysfunction, including VIAGRA, should not be generally used in men for whom sexual activity is inadvisable because of their underlying cardiovascular status. The evaluation of erectile dysfunction should include a determination of potential underlying causes and the identification of appropriate treatment following a complete medical assessment.

VIAGRA has systemic vasodilatory properties that resulted in transient decreases in supine blood pressure in healthy volunteers (mean maximum decrease of 8.4/5.5 mmHg), . While this normally would be expected to be of little consequence in most patients, prior to prescribing VIAGRA, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects, especially in combination with sexual activity. Use with caution in patients with the following underlying conditions which can be particularly sensitive to the actions of vasodilators including VIAGRA – those with left ventricular outflow obstruction (e.g., aortic stenosis, idiopathic hypertrophic subaortic stenosis) and those with severely impaired autonomic control of blood pressure. There are no controlled clinical data on the safety or efficacy of VIAGRA in the following groups; if prescribed, this should be done with caution. • Patients who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; • Patients with resting hypotension (BP <90/50 mmHg) or hypertension (BP >170/110 mmHg); • Patients with cardiac failure or coronary artery disease causing unstable angina.

5.2Prolonged Erection and Priapism Prolonged

erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of VIAGRA. In the event of an erection that persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result. VIAGRA should be used with caution in patients with anatomical deformation of the penis (such as angulation, cavernosal fibrosis or Peyronie’s disease), or in patients who have conditions which may predispose them to priapism (such as sickle cell anemia, multiple myeloma, or leukemia).

However, there are no controlled clinical data on the safety or efficacy of VIAGRA in patients with sickle cell or related anemias.

5.3Effects on the Eye Physicians

should advise patients to stop use of all phosphodiesterase type 5 (PDE5) inhibitors, including VIAGRA, and seek medical attention in the event of a sudden loss of vision in one or both eyes. Such an event may be a sign of non-arteritic anterior ischemic optic neuropathy (NAION), a rare condition and a cause of decreased vision including permanent loss of vision, that has been reported rarely post-marketing in temporal association with the use of all PDE5 inhibitors. Based on published literature, the annual incidence of NAION is 2.5-11.8 cases per 100,000 in males aged ≥ 50.

An observational case-crossover study evaluated the risk of NAION when PDE5 inhibitor use, as a class, occurred immediately before NAION onset (within 5 half-lives), compared to PDE5 inhibitor use in a prior time period. The results suggest an approximate 2-fold increase in the risk of NAION, with a risk estimate of 2.15 (95% CI 1.06, 4.34). A similar study reported a consistent result, with a risk estimate of 2.27 (95% CI 0.99, 5.20).

Other risk factors for NAION, such as the presence of “crowded” optic disc, may have contributed to the occurrence of NAION in these studies. Neither the rare post-marketing reports, nor the association of PDE5 inhibitor use and NAION in the observational studies, substantiate a causal relationship between PDE5 inhibitor use and NAION . Physicians should consider whether their patients with underlying NAION risk factors could be adversely affected by use of PDE5 inhibitors. Individuals who have already experienced NAION are at increased risk of NAION recurrence.

Therefore, PDE5 inhibitors, including VIAGRA, should be used with caution in these patients and only when the anticipated benefits outweigh the risks. Individuals with “crowded” optic disc are also considered at greater risk for NAION compared to the general population, however, evidence is insufficient to support screening of prospective users of PDE5 inhibitors, including VIAGRA, for this uncommon condition. There are no controlled clinical data on the safety or efficacy of VIAGRA in patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases); if prescribed, this should be done with caution.

5.4Hearing Loss Physicians

should advise patients to stop taking PDE5 inhibitors, including VIAGRA, and seek prompt medical attention in the event of sudden decrease or loss of hearing. These events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to the intake of PDE5 inhibitors, including VIAGRA. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors .

5.5Hypotension

when Co-administered with Alpha-blockers or Anti-hypertensives Alpha-blockers Caution is advised when PDE5 inhibitors are co-administered with alpha-blockers. PDE5 inhibitors, including VIAGRA, 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 occur.

In some patients, concomitant use of these two drug classes can lower blood pressure significantly leading to symptomatic hypotension (e.g., dizziness, lightheadedness, fainting). Consideration should be given to the following: • Patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors. Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor. • In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest dose . • In those patients already taking an optimized dose of a PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose.

Stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure when taking a PDE5 inhibitor. • Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs. Anti-hypertensives VIAGRA has systemic vasodilatory properties and may further lower blood pressure in patients taking anti-hypertensive medications. In a separate drug interaction study, when amlodipine, 5 mg or 10 mg, and VIAGRA, 100 mg were orally administered concomitantly to hypertensive patients mean additional blood pressure reduction of 8 mmHg systolic and 7 mmHg diastolic were noted .

5.6Adverse Reactions with the Concomitant Use of Ritonavir

The concomitant administration of the protease inhibitor ritonavir substantially increases serum concentrations of sildenafil (11-fold increase in AUC). If VIAGRA is prescribed to patients taking ritonavir, caution should be used. Data from subjects exposed to high systemic levels of sildenafil are limited.

Decreased blood pressure, syncope, and prolonged erection were reported in some healthy volunteers exposed to high doses of sildenafil (200-800 mg). To decrease the chance of adverse reactions in patients taking ritonavir, a decrease in sildenafil dosage is recommended .

5.7Combination with Other PDE5 Inhibitors or Other

Erectile Dysfunction Therapies The safety and efficacy of combinations of VIAGRA with other PDE5 Inhibitors, including REVATIO or other pulmonary arterial hypertension (PAH) treatments containing sildenafil, or other treatments for erectile dysfunction have not been studied. Such combinations may further lower blood pressure. Therefore, the use of such combinations is not recommended.

5.8Effects on Bleeding There

have been postmarketing reports of bleeding events in patients who have taken VIAGRA. A causal relationship between VIAGRA and these events has not been established. In humans, VIAGRA has no effect on bleeding time when taken alone or with aspirin. However, in vitro studies with human platelets indicate that sildenafil potentiates the antiaggregatory effect of sodium nitroprusside (a nitric oxide donor).

In addition, the combination of heparin and VIAGRA had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans. The safety of VIAGRA is unknown in patients with bleeding disorders and patients with active peptic ulceration.

5.9Counseling Patients About Sexually Transmitted

Diseases The use of VIAGRA offers no protection against sexually transmitted diseases. Counseling of patients about the protective measures necessary to guard against sexually transmitted diseases, including the Human Immunodeficiency Virus (HIV), may be considered.

4 CONTRAINDICATIONS • Administration of VIAGRA to patients using nitric oxide donors, such as organic nitrates or organic nitrites in any form. VIAGRA was shown to potentiate the hypotensive effect of nitrates ( 4.1 , 7.1 , 12.2 ) • Known hypersensitivity to sildenafil or any component of tablet • Administration with guanylate cyclase (GC) stimulators, such as riociguat

4.1Nitrates Consistent with

its known effects on the nitric oxide/cGMP pathway , VIAGRA was shown to potentiate the hypotensive effects of nitrates, and its administration to patients who are using nitric oxide donors such as organic nitrates or organic nitrites in any form either regularly and/or intermittently is therefore contraindicated. After patients have taken VIAGRA, it is unknown when nitrates, if necessary, can be safely administered. Although plasma levels of sildenafil at 24 hours post dose are much lower than at peak concentration, it is unknown whether nitrates can be safely co-administered at this time point .

4.2Hypersensitivity Reactions

VIAGRA is contraindicated in patients with a known hypersensitivity to sildenafil, as contained in VIAGRA and REVATIO, or any component of the tablet. Hypersensitivity reactions have been reported, including rash and urticaria .

4.3Concomitant Guanylate Cyclase

(GC) Stimulators Do not use VIAGRA in patients who are using a GC stimulator, such as riociguat. PDE5 inhibitors, including VIAGRA, may potentiate the hypotensive effects of GC stimulators.

8.1Pregnancy Risk Summary

VIAGRA is not indicated for use in females. There are no data with the use of VIAGRA in pregnant women to inform any drug-associated risks for adverse developmental outcomes. Animal reproduction studies conducted with sildenafil did not show adverse developmental outcomes when administered during organogenesis in rats and rabbits at oral doses up to 16 and 32 times, respectively, the maximum recommended human dose (MRHD) of 100 mg/day on a mg/m 2 basis . Data Animal Data No evidence of teratogenicity, embryotoxicity or fetotoxicity was observed in rats and rabbits which received oral doses up to 200 mg/kg/day during organogenesis.

These doses represent, respectively, about 16 and 32 times the MRHD on a mg/m 2 basis in a 50 kg subject. In the rat pre- and postnatal development study, the no observed adverse effect dose was 30 mg/kg/day given for 36 days, about 2 times the MRHD on a mg/m 2 basis in a 50 kg subject.

The following are discussed in more detail in other sections of the labeling: • Cardiovascular • Prolonged Erection and Priapism • Effects on the Eye • Hearing Loss • Hypotension when Co-administered with Alpha-blockers or Anti-hypertensives • Adverse Reactions with the Concomitant Use of Ritonavir • Combination with other PDE5 Inhibitors or Other Erectile Dysfunction Therapies • Effects on Bleeding • Counseling Patients About Sexually Transmitted Diseases The most common adverse reactions reported in clinical trials (≥ 2%) are headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness, and rash. Most common adverse reactions (≥ 2%) include headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness and rash To report SUSPECTED ADVERSE REACTIONS, contact Viatris at 1-877-446-3679 (1-877-4-INFO-RX) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical 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. VIAGRA was administered to over 3700 patients (aged 19-87 years) during pre-marketing clinical trials worldwide. Over 550 patients were treated for longer than one year.

In placebo-controlled clinical studies, the discontinuation rate due to adverse reactions for VIAGRA (2.5%) was not significantly different from placebo (2.3%). In fixed-dose studies, the incidence of some adverse reactions increased with dose. The type of adverse reactions in flexible-dose studies, which reflect the recommended dosage regimen, was similar to that for fixed-dose studies.

At doses above the recommended dose range, adverse reactions were similar to those detailed in Table 1 below but generally were reported more frequently. Table 1. Adverse Reactions Reported by ≥2% of Patients Treated with VIAGRA and More Frequent than Placebo in Fixed-Dose Phase II/III Studies Adverse Reaction 25 mg (n=312) 50 mg (n=511) 100 mg (n=506) Placebo (n=607) Headache 16% 21% 28% 7% Flushing 10% 19% 18% 2% Dyspepsia 3% 9% 17% 2% Abnormal Vision Abnormal Vision: Mild to moderate in severity and transient, predominantly color tinge to vision, but also increased sensitivity to light, or blurred vision. 1% 2% 11% 1% Nasal Congestion 4% 4% 9% 2% Back Pain 3% 4% 4% 2% Myalgia 2% 2% 4% 1% Nausea 2% 3% 3% 1% Dizziness 3% 4% 3% 2% Rash 1% 2% 3% 1% When VIAGRA was taken as recommended (on an as-needed basis) in flexible-dose, placebo-controlled clinical trials of two to twenty-six weeks duration, patients took VIAGRA at least once weekly, and the following adverse reactions were reported: Table 2.

Adverse Reactions Reported by ≥2% of Patients Treated with VIAGRA and More Frequent than Placebo in Flexible-Dose Phase II/III Studies Adverse Reaction VIAGRA PLACEBO N=734 N=725 Headache 16% 4% Flushing 10% 1% Dyspepsia 7% 2% Nasal Congestion 4% 2% Abnormal Vision Abnormal Vision: Mild and transient, predominantly color tinge to vision, but also increased sensitivity to light or blurred vision. In these studies, only one patient discontinued due to abnormal vision. 3% 0% Back Pain 2% 2% Dizziness 2% 1% Rash 2% 1% The following events occurred in <2% of patients in controlled clinical trials; a causal relationship to VIAGRA is uncertain. Reported events include those with a plausible relation to drug use; omitted are minor events and reports too imprecise to be meaningful: Body as a Whole: face edema, photosensitivity reaction, shock, asthenia, pain, chills, accidental fall, abdominal pain, allergic reaction, chest pain, accidental injury.

Cardiovascular: angina pectoris, AV block, migraine, syncope, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathy. Digestive: vomiting, glossitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, dry mouth, liver function tests abnormal, rectal hemorrhage, gingivitis. Hemic and Lymphatic: anemia and leukopenia.

Metabolic and Nutritional: thirst, edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremia. Musculoskeletal: arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitis. Nervous: ataxia, hypertonia, neuralgia, neuropathy, paresthesia, tremor, vertigo, depression, insomnia, somnolence, abnormal dreams, reflexes decreased, hypesthesia.

Respiratory: asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increased. Skin and Appendages: urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitis. Special Senses: sudden decrease or loss of hearing, mydriasis, conjunctivitis, photophobia, tinnitus, eye pain, ear pain, eye hemorrhage, cataract, dry eyes.

Urogenital: cystitis, nocturia, urinary frequency, breast enlargement, urinary incontinence, abnormal ejaculation, genital edema and anorgasmia. Analysis of the safety database from controlled clinical trials showed no apparent difference in adverse reactions in patients taking VIAGRA with and without anti-hypertensive medication. This analysis was performed retrospectively, and was not powered to detect any pre-specified difference in adverse reactions.

6.2Postmarketing Experience The

following adverse reactions have been identified during post approval use of VIAGRA. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. These events have been chosen for inclusion either due to their seriousness, reporting frequency, lack of clear alternative causation, or a combination of these factors. Cardiovascular and Cerebrovascular Serious cardiovascular, cerebrovascular, and vascular events, including myocardial infarction, sudden cardiac death, ventricular arrhythmia, cerebrovascular hemorrhage, transient ischemic attack, hypertension, subarachnoid and intracerebral hemorrhages, and pulmonary hemorrhage have been reported post-marketing in temporal association with the use of VIAGRA. Most, but not all, of these patients had preexisting cardiovascular risk factors.

Many of these events were reported to occur during or shortly after sexual activity, and a few were reported to occur shortly after the use of VIAGRA without sexual activity. Others were reported to have occurred hours to days after the use of VIAGRA and sexual activity. It is not possible to determine whether these events are related directly to VIAGRA, to sexual activity, to the patient’s underlying cardiovascular disease, to a combination of these factors, or to other factors . Hemic and Lymphatic: vaso-occlusive crisis: In a small, prematurely terminated study of REVATIO (sildenafil) in patients with pulmonary arterial hypertension (PAH) secondary to sickle cell disease, vaso-occlusive crises requiring hospitalization were more commonly reported in patients who received sildenafil than in those randomized to placebo.

The clinical relevance of this finding to men treated with VIAGRA for ED is not known. Nervous: seizure, seizure recurrence, anxiety, and transient global amnesia. Respiratory: epistaxis Special senses Hearing: Cases of sudden decrease or loss of hearing have been reported postmarketing in temporal association with the use of PDE5 inhibitors, including VIAGRA. In some of the cases, medical conditions and other factors were reported that may have also played a role in the otologic adverse events.

In many cases, medical follow-up information was limited. It is not possible to determine whether these reported events are related directly to the use of VIAGRA, to the patient’s underlying risk factors for hearing loss, a combination of these factors, or to other factors . Ocular: diplopia, temporary vision loss/decreased vision, ocular redness or bloodshot appearance, ocular burning, ocular swelling/pressure, increased intraocular pressure, retinal edema, retinal vascular disease or bleeding, and vitreous traction/detachment. Non-arteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision, has been reported rarely post-marketing in temporal association with the use of phosphodiesterase type 5 (PDE5) inhibitors, including VIAGRA. Most, but not all, of these patients had underlying anatomic or vascular risk factors for developing NAION, including but not necessarily limited to: low cup to disc ratio (“crowded disc”), age over 50, diabetes, hypertension, coronary artery disease, hyperlipidemia and smoking . Urogenital: prolonged erection, priapism , and hematuria.