Sildenafil, the active drug in the commonly used erectile dysfunction drug Viagra, has been approved to treat pulmonary hypertension in US.
The new formulation with brand name Revatio has been approved by US FDA to treat pulmonary hypertension.
Revatio is the only FDA-approved phosphodiesterase-5 (PDE5) inhibitor available in both tablet and intravenous formulations.
Revatio is indicated for the treatment of adult patients with pulmonary arterial hypertension to improve exercise ability and delay clinical worsening. The delay in clinical worsening was demonstrated when Revatio was added to background epoprostenol therapy.
However, the efficacy of Revatio has not been adequately evaluated in patients taking bosentan concurrently.
Revatio injection is for the continued treatment of patients with pulmonary arterial hypertension who are currently prescribed Revatio Tablets but who are temporarily unable to take oral medication.
Pulmonary arterial hypertension is characterized by continuous high blood pressure in the pulmonary arteries, often leading to heart failure and premature death. This is a rare, progressive disease that affects an estimated 100,000 men and women worldwide. This incurable disease pulmonary arterial hypertension can occur with no known underlying cause, or it can occur in association with other disorders.
Maintaining medical therapy can delay clinical worsening for patients. However, in some cases, oral medication may not be an option for a period of time. While oral treatment can often be re-introduced at a later stage, the ability to maintain treatment during periods when the patient is unable to take an oral formulation is important to preserving health in patients with pulmonary arterial hypertension.
Revatio tablets were approved by US FDA in June 2005 and by the European Medicines Agency (EMEA) in November 2005. The American College of Chest Physicians recommends Revatio for adult pulmonary arterial hypertension patients in functional class II and III in its clinical practice guidelines for the treatment of pulmonary arterial hypertension.
Revatio injection will be supplied in a single-use vial. The recommended dose of Revatio injection is 10 mg (corresponding to 12.5 mL) administered as an intravenous bolus injection three times a day. Revatio is also available as a 20 mg tablet taken three times a day.
Revatio is not recommended, if patients have ever had blockage of veins in their lungs, which is called pulmonary veno-occlusive disease.
Revatio is also not recommended for patients taking ritonavir or antifungal medicines, such as ketoconazole and itraconazole.
If patients are taking Revatio with bosentan or medicines like barbiturates, carbamazepine, phenytoin, efavirenz, nevirapine, rifampin or rifabutin, their doctor may adjust their dose.
Taking vitamin K antagonists (like Coumadin or warfarin) with Revatio may increase risk of nosebleeds. Patients should tell their doctor if they take such medicines.
The safety of Revatio is not known in patients with bleeding problems and those with stomach ulcers.
Sudden decrease or loss of hearing has been reported in people taking PDE5 inhibitors, including Revatio.
The most common side effects of Revatio are nosebleeds, headache, upset stomach, flushing, and trouble sleeping.