Clinical Trials and Efficacy Data

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Continuing Education Activity

Population pharmacokinetic analysis of data from patients in clinical trials indicated an approximately 30% reduction in sildenafil clearance when it was co-administered with mild/moderate CYP3A inhibitors and an approximately 34% reductions in sildenafil clearance when co-administered with beta-blockers. Sildenafil exposure without concomitant medication is shown to be 5-fold the exposure at a dose of 20 mg three times a day. This concentration range covers the same increased sildenafil exposure observed in specifically-designed drug interaction studies with CYP3A inhibitors (except for potent inhibitors such as ketoconazole, itraconazole, and ritonavir). Concomitant administration of potent CYP3A inducers is expected to cause substantial decreases in plasma levels of sildenafil. The mean reduction of sildenafil (80 mg three times a day) bioavailability when administered with epoprostenol was 28%, resulting in about 22% lower mean average steady-state concentrations.

Dosage Modifications

Therefore, the slight decrease of sildenafil exposure in the presence of epoprostenol is not considered clinically relevant. No significant interactions were shown with tolbutamide (250 mg) or warfarin (40 mg), both of which are metabolized by CYP2C9. Sildenafil (50 mg) did not potentiate the hypotensive effect of alcohol in healthy volunteers with mean maximum blood alcohol levels of 0.08%. A randomized, double-blind, placebo-controlled study of sildenafil citrate (Study 1) was conducted in 277 patients with PAH (defined as a mean pulmonary artery pressure of greater than 25 mmHg at rest with a pulmonary capillary wedge pressure less than 15 mmHg). Patients were predominantly World Health Organization (WHO) functional classes II-III.

What is sildenafil used for?

Allowed background therapy included a combination of anticoagulants, digoxin, calcium channel blockers, diuretics, and oxygen. The use of prostacyclin analogues, endothelin receptor antagonists, and arginine supplementation were not permitted. Subjects who had failed to respond to bosentan were also excluded. Patients with left ventricular ejection fraction less than 45% or left ventricular shortening fraction less than 0.2 also were not studied. Patients were randomized to receive placebo (n=70) or sildenafil citrate 20 mg (n = 69), 40 mg (n = 67) or 80 mg (n = 71) TID for a period of 12 weeks. Nitroglycerin in any form including tablets,

patches, sprays, and ointments Nitroglycerin in any

Frequently asked questions

At baseline patients had PPH (80%) or PAH secondary to CTD (20%);WHO functional class I (1%), II (26%), III (67%), or IV (6%); and the mean age was 48 years, 80% were female, and 79% were Caucasian. There was a statistically significant greater increase from baseline in 6-minute walk distance at Week 16 (primary endpoint) for the sildenafil citrate group compared with the placebo group. The mean change from baseline at Week 16 (last observation carried forward) was 30 meters for the sildenafil citrate group compared with 4 meters for the placebo group giving an adjusted treatment difference of 26 meters (95% CI: 10.8, 41.2) (p = 0.0009). Patients on sildenafil citrate achieved a statistically significant reduction in mPAP compared to those on placebo. A mean placebo-corrected treatment effect of -3.9 mmHg was observed in favor of sildenafil citrate (95% CI: -5.7, -2.1) (p = 0.00003).

Mechanism of Action

Time to clinical worsening of PAH was defined as the time from randomization to the first occurrence of a clinical worsening event (death, lung transplantation, initiation of bosentan therapy, or clinical deterioration requiring a change in epoprostenol therapy). Table 4 displays the number of patients with clinical worsening events in sildenafil citrates Study 2. Kaplan-Meier estimates and a stratified log-rank test demonstrated that placebo-treated patients were 3 times more likely to experience a clinical worsening event than sildenafil citrate-treated patients and that sildenafil citrate-treated patients experienced a significant delay in time to clinical worsening versus placebo-treated patients (p = 0.0074). Kaplan-Meier plot of time to clinical worsening is presented in Figure 11. Improvements in WHO functional class for PAH were also demonstrated in subjects on sildenafil citrate compared to placebo.

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More than twice as many sildenafil citrate-treated patients (36%) as placebo-treated patients (14%) showed an improvement in at least one functional New York Heart Association (NYHA) class for PAH. A randomized, double-blind, parallel dose study (Study 3) was planned in 219 patients with PAH. This study was prematurely terminated with 129 subjects enrolled. Patients were required to have a mPAP greater than or equal to 25 mmHg and a PCWP less than or equal to 15 mmHg at rest via right heart catheterization within 12 weeks before randomization, and a baseline 6-minute walk test distance greater than or equal to 100 meters and less than or equal to 450 meters (mean 345 meters). Patients were randomized to 1 of 3 doses of sildenafil citrate: 1 mg, 5 mg, and 20 mg, three times a day. form including tablets, patches, sprays, and

• Sildenafil is unsuitable for individuals with severe liver disease.
• Patients should avoid alcohol consumption during treatment.
• Some side effects may resolve on their own within hours.
• Persistent side effects should prompt medical consultation.
• The drug does not cure ED but manages symptoms.
• Lifestyle changes can also improve erectile function.
• Follow your healthcare provider’s instructions precisely.

ointments Street drugs called “poppers” (amyl nitrate

• Sildenafil can enhance the effects of other blood pressure medications.
• The drug’s safety profile is well-studied with many clinical trials.
• Cardiovascular health is an important consideration when taking sildenafil.
• Long-term use requires monitoring for adverse reactions.
• Patient education helps reduce risks and optimize dosage.
• Generic sildenafil offers a cost-effective alternative to branded Viagra.
• Regular health assessments can ensure safe usage.

or nitrite) Street drugs called “poppers”

• Sildenafil citrate was first approved by the FDA in 1998.
• Its brand name is Viagra, but generic versions are available.
• The drug is available in tablets of various strengths, typically 25-100 mg.
• It can be prescribed for both men and in specific cases, women.
• Proper dosage varies based on health status and response.
• Use caution in patients with heart problems or low blood pressure.
• It is not a hormone or a testosterone booster.

(amyl nitrate or nitrite) Ask your doctor

Route of administration

At baseline patients had PPH (74%) or secondary PAH (26%); WHO functional class II (57%), III (41%), or IV (2%); the mean age was 44 years; and 67% were female. The majority of subjects were Asian (67%), and 28% were Caucasian. Similar increases in walk distance (mean increase of 38 to 41 meters) were observed in the 5 and 20 mg dose groups. These increases were significantly better than those observed in the 1 mg dose group (Figure 12). A randomized, double-blind, placebo controlled study was conducted in 103 patients with PAH who were on bosentan therapy for a minimum of three months.

Raynaud's phenomenon

The PAH patients included those with primary PAH, and PAH associated with CTD. Patients were randomized to placebo or sildenafil (20 mg three times a day) in combination with bosentan (62.5 to 125 mg twice a day). The primary efficacy endpoint was the change from baseline at Week 12 in 6MWD. The results indicate that there is no significant difference in mean change from baseline on 6MWD observed between sildenafil 20 mg plus bosentan and bosentan alone. Sildenafil tablets, 20 mg, are supplied as white to off-white, round shaped film-coated tablets with debossing ‘AN 351’ on one side and plain on the other side, containing sildenafil citrate, USP equivalent to the nominally indicated amount of sildenafil.

Common Side Effects

Bottles of 90: NDC 68001-176-05 Bottles of 90: NDC 68001-176-05 Recommended Storage for Sildenafil Tablets: Store at controlled room temperature 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F). {{#ask: Page Name::Sildenafil ?Pill Name ?Drug Name ?Pill Ingred ?Pill Imprint ?Pill Dosage ?Pill Color ?Pill Shape ?Pill Size (mm) ?Pill Scoring ?NDC ?Drug Author format=template template=DrugPageImages mainlabel=- sort=Pill Name }} {{#ask: Label Page::Sildenafil ?Label Name format=template template=DrugLabelImages mainlabel=- sort=Label Page }} Read this Patient Information before you start taking sildenafil citrate and each time you get a refill. This information does not take the place of talking with your doctor about your medical condition or treatment. If you have any questions about sildenafil citrate, ask your doctor or pharmacist. Never take sildenafil citrate with any nitrate medicines. or pharmacist if you are not sure

What special dietary instructions should I follow?

They had either primary pulmonary hypertension (PPH) (63%), PAH associated with CTD (30%), or PAH following surgical repair of left-to-right congenital heart lesions (7%). The study population consisted of 25% men and 75% women with a mean age of 49 years (range: 18 to 81 years) and baseline 6-minute walk distance between 100 and 450 meters (mean 343). The primary efficacy endpoint was the change from baseline at week 12 (at least 4 hours after the last dose) in the 6-minute walk distance. Placebo-corrected mean increases in walk distance of 45 to 50 meters were observed with all doses of sildenafil citrate. These increases were significantly different from placebo, but the sildenafil citrate dose groups were not different from each other (see Figure 9), indicating no additional clinical benefit from doses higher than 20 mg TID.

Recreational use

The improvement in walk distance was apparent after 4 weeks of treatment and was maintained at week 8 and week 12. Figure 10 displays subgroup efficacy analyses in Study 1 for the change from baseline in 6-Minute Walk Distance at Week 12 including baseline walk distance, disease etiology, functional class, gender, age, and hemodynamic parameters. Key: PAH = pulmonary arterial hypertension; CTD = connective tissue disease; PH = pulmonary hypertension; PAP = pulmonary arterial pressure; PVRI = pulmonary vascular resistance index; TID = three times daily. Of the 277 treated patients, 259 entered a long-term, uncontrolled extension study. At the end of 1 year, 94% of these patients were still alive.

Azole Antifungals

Additionally, walk distance and functional class status appeared to be stable in patients taking sildenafil citrate. Without a control group, these data must be interpreted cautiously. A randomized, double-blind, placebo controlled study (Study 2) was conducted in 267 patients with PAH who were taking stable doses of intravenous epoprostenol. Patients had to have a mean pulmonary artery pressure (mPAP) greater than or equal to 25 mmHg and a pulmonary capillary wedge pressure (PCWP) less than or equal to 15 mmHg at rest via right heart catheterization within 21 days before randomization, and a baseline 6-minute walk test distance greater than or equal to 100 meters and less than or equal to 450 meters (mean 349 meters). Patients were randomized to placebo or sildenafil citrate (in a fixed titration starting from 20 mg, to 40 mg and then 80 mg, three times a day) and all patients continued intravenous epoprostenol therapy. if you are taking a nitrate medicine.