FDA Approves New Erectile Dysfunction Remedy
The Food and Drug Administration (FDA) yesterday approved the marketing of vardenafil hydrochloride oral tablets, or Levitra, for the treatment of erectile dysfunction in men.
Vardenafil is a vasodilator that exerts its chief effect by causing improved blood flow to the penis. The product is comarketed by Bayer Pharmaceuticals Corp. and GlaxoSmithKline. The companies have stated that vardenafil should be available in pharmacies within the next few weeks.
According to the product's labeling, the recommended starting dosage for most men is 10 mg taken with or without food one hour before sexual activity. The product should be used no more than once a day. Lower dosages are recommended for men concurrently treated with certain strong inhibitors of the cytochrome P-450 3A4 isoenzyme, such as ritonavir, indinavir, erythromycin, and ketoconazole.
The labeling recommends that men age 65 years or older consider starting vardenafil treatment at 5 mg per dose instead of the usual 10 mg.
Vardenafil must not be administered to men who take nitrates, nitric oxide donors, or alpha-blockers, because concurrent use of the products can lead to a dangerous drop in blood pressure. Men with a prolonged cardiac QT interval should not use vardenafil.
According to FDA, men who have suffered a myocardial infarction or stroke within the past six months should not take vardenafil. Other conditions not compatible with the drug include significantly low blood pressure, uncontrolled high blood pressure, unstable angina, severe liver disease, end-stage renal disease, and the ocular disorder retinitis pigmentosa.
In clinical trials, the most frequently cited adverse events among vardenafil users were headache, flushing, nasal congestion, and indigestion. The labeling notes that rare instances of priapism have been reported by men using vardenafil. Men are cautioned to seek medical treatment if an erection persists for more than four hours after the administration of vardenafil.
The product will be supplied in 30-count bottles of 2.5, 5, 10, or 20 mg of vardenafil and six-count packages of 10 or 20 mg vardenafil.
Vardenifil, a selective inihibitor of guanosine monophosphate-specific phosphodiesterase type 5, is the second drug in this class to receive FDA's approval for marketing as an erectile dysfunction remedy. Pfizer Inc.'s sildenafil citrate was approved in 1998.