Alteplase, a recombinant tissue plasminogen activator (TPA; Activase - Genentech), has been approved by the US Food and Drug Administration (FDA) for intravenous (IV) treatment of acute ischemic stroke. Several thrombolytic agents, including alteplase, were previously approved for use in acute myocardial infarction and acute massive pulmonary embolism (Medical Letter, 29:107, 1987; 32:15, 1990).

Sodium phenylbutyrate, an "orphan drug,"has recently been marketed for the treatment of patients with urea cycle disorders caused by a deficiency in one of the following hepatic enzymes: carbamyl phosphate synthetase (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase (AS). Urea cycle disorders are rare; they occur in one of every 10,000 births.

Reteplase (Retavase - Boehringer Mannheim), a recombinant protein derivative of human tissue plasminogen activator (t-PA), has been marketed in the USA for thrombolysis in patients with acute myocardial infarction.

Cabergoline (Dostinex - Pharmacia & Upjohn), an ergot alkaloid derivative recently marketed for treatment of hyperprolactinemia, is a selective D2 dopamine agonist that inhibits prolactin-secreting cells in the pituitary. Bromocriptine (Parlodel - Sandoz), the drug most commonly used for this condition, is also a D2 agonist, but affects D1 receptors as well.

Irbesartan (Avapro - Sanofi/Bristol-Myers Squibb) is the third angiotensin II receptor antagonist to become available in the USA for oral treatment of hypertension. Losartan (Cozaar) and valsartan (Diovan) were marketed earlier. Eprosartan (Teveten - SmithKline Beecham) has been approved by the FDA but not marketed.

The US Food and Drug Administration has ordered removal of phenylpropanolamine from over-the-counter cold remedies and weight loss aids. The FDA based its decision on a recent study showing an increased risk of hemorrhagic stroke in young women taking the drug.

The media recently reported that the FDA has threatened to withdraw Synthroid from the market, alarming many physicians and patients.

An unpublished 2-year randomized study (ENHANCE) on the effect of adding ezetimibe 10 mg to simvastatin 80 mg in 720 patients with heterozygous familial hypercholesterolemia has been in the news recently. About 80% of these patients had previously been treated with statins. The primary endpoint was the change in the intima-media thickness (IMT) of the carotid artery (baseline 0.68 and 0.69 mm); the IMT increased by 0.0111 mm with ezetimibe plus simvastatin and 0.0058 mm with simvastatin 80 mg alone (p=0.29). The ezetimibe- simvastatin combination lowered LDL-C by 58% compared to 41% lowering...

Colesevelam (Welchol - Daiichi Sankyo - Med Lett Drugs Ther 2000; 42:102), a bile-acid sequestrant used to lower LDL cholesterol, has been approved by the FDA as an adjunct to diet and exercise in the treatment of type 2 diabetes. In unpublished studies summarized in the package insert, patients with type 2 diabetes taking metformin (Glucophage, and others), a sulfonylurea or insulin (each as either monotherapy or in combination with other anti-diabetic agents) were given colesevelam 3800 mg per day or placebo; colesevelam significantly reduced glycosylated hemoglobin (A1c) by about 0.5% more...

The May 5, 2008 article (Med Lett Drugs Ther 2008; 50:34) on the approval of natalizumab (Tysabri) for treatment of Crohn's disease in the "Adverse Effects" section on page 35 included the statement: "post-marketing hepatotoxicity, sometimes fatal or requiring liver transplantation, has occurred." Actually, no fatal hepatotoxicity or liver transplantation has been reported to date. The FDA warning about post-marketing hepatotoxicity with Tysabri that was the basis for our statement said: "The combination of transaminase elevations and elevated bilirubin without evidence of obstruction is...