REVATIO

What it is

Sildenafil Wafer-ISPL is a sublingual wafer formulation of sildenafil citrate, available in strengths of 25 mg or 50 mg per wafer. The 25 mg wafers are light pink to pink oval discs, while the 50 mg wafers are light yellow to yellow oval discs. The wafers are administered sublingually.

Approved indications

— Treatment of erectile dysfunction in adult males.

Dosing overview

The recommended dose is 50 mg taken as needed approximately one hour before sexual activity. Based on efficacy and toleration, the dose may be increased to 100 mg or decreased to 25 mg, with a maximum recommended dose of 100 mg. The maximum recommended dosing frequency is once per day. The wafer should be kept under the tongue until it has dissolved, which takes an average of 2–3 minutes. No food or drink should be consumed until the wafer has dissolved, and the wafers should not be chewed, sucked or swallowed.

Key safety warnings

Nitrates and sildenafil must not be used concomitantly, as sildenafil potentiates the hypotensive effects of nitrates and their co-administration with glyceryl trinitrate, isosorbide salts, sodium nitroprusside, amyl nitrite, nicorandil or organic nitrates in any form is contraindicated. Patients should stop use of sildenafil and seek immediate medical attention in the event of sudden loss of vision in one or both eyes, as this may be a sign of non-arteritic anterior ischaemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision that has been reported rarely post-marketing in temporal association with the use of phosphodiesterase type 5 inhibitors. Prolonged erections greater than four hours and priapism have been reported infrequently since market approval; if an erection persists longer than four hours, the patient should seek immediate medical assistance, as untreated priapism may result in penile tissue damage and permanent loss of potency. As transient visual disturbances and dizziness have been reported in some patients taking sildenafil, particularly at the 100 mg dose, patients should be aware of how they react to sildenafil before driving or operating machinery.

Contraindications

Use of sildenafil is contraindicated in patients with known hypersensitivity to any component of the wafer. The co-administration of phosphodiesterase type 5 inhibitors, including sildenafil, with guanylate cyclase stimulators such as riociguat is contraindicated as it may potentially lead to symptomatic hypotension. Sildenafil is contraindicated in men for whom sexual intercourse is inadvisable due to cardiovascular risk factors, such as patients with severe cardiovascular disease including established cardiac failure and unstable angina pectoris. Sildenafil is not recommended in patients with male erectile dysfunction with a previous episode of non-arteritic anterior ischaemic optic neuropathy. The safety of sildenafil has not been studied in patients with severe hepatic impairment, hypotension (blood pressure <90/50 mmHg), hypertension (blood pressure >170/110 mmHg), recent history of stroke or myocardial infarction and known hereditary degenerative retinal disorders such as retinitis pigmentosa, and its use is therefore contraindicated in these populations until further information is available.

Regulatory history

Sildenafil Wafer-ISPL (Sildenafil Wafer-ISPL) received its first approval on 14 June 2018. The REVATIO brand includes ARTG registrations for a 20 mg tablet (first listed 2006-08-14) and a 10 mg/12.5 mL solution for injection (first listed 2011-09-23). An AusPAR was approved on 2011-09-16 for oral Revatio for the treatment of patients with pulmonary arterial hypertension classified as WHO functional classes II and III to improve exercise capacity.