Generic Zocor - Simvastatin

Prior to losing U.S. patent protection, simvastatin was Merck & Co.’s largest selling drug and second largest selling cholesterol lowering drug in the world; it recorded 4.3 billion dollars of sales in 2005. Zocor had an original patent expiration date of January 2006 but was extended by the United States Food and Drug Administration (FDA) to expire on June 23, 2006. The FDA granted the patent extension after Merck & Co, Inc. submitted data from studies of the drug’s positive effect on children, a move typically used by drug companies to lengthen exclusivity. In the UK the patent for simvastatin had expired by 2004.

Ordinarily, Merck & Co. would have expected a sharp decrease in sales after the generic versions of simvastatin entered the market; however, Merck has slashed the price of Zocor dramatically in an effort to claim sales that would have otherwise gone to the generic versions. At least two major U.S. health insurers, UnitedHealthcare and WellPoint, are now offering Zocor to their members at generic copays.

In addition, since Merck & Co. itself manufactures at least some versions of Dr. Reddy’s authorized generic simvastatin. Merck & Co. is also poised to profit from the Dr. Reddy’s version. An 80 mg, 30-count bottle of Dr. Reddy’s simvastatin obtained July 6, 2006, states it is made by Merck Sharp & Dohme (Merck & Co.’s name outside the US to avoid conflicts with Merck KGaA) in the UK, just like 80 mg Zocor, and has a Merck & Co. logo on the bottom; except for omitting the “80″ on one side, the tablets are visually identical to 80 mg Zocor, including “543″ on the other side which is the key part of the National Drug Code for 80 mg Zocor.

Simvastatin was initially marketed by Merck & Co under the trade name Zocor, but is now also available generically in most countries following the patent expiry. A combination of Simvastatin along with Ezetimibe is currently sold under the brand name Vytorin and is jointly marketed by Merck and Schering-Plough.

Brand names: Zocor, Zocor Heart Pro, marketed by the pharmaceutical company Merck & Co. Simlup,Simvotin, Simcard [India] Denan (Germany), Liponorm, Sinvacor, Sivastin (Italy), Lipovas (Japan), Lodales (France), Zocord (Austria and Sweden), Zimstat, Simvahexal (Australia), Lipex (Australia and New Zealand), Simvastatin-Teva, Simvacor, Simvaxon, Simovil (Israel)and others.

The primary US patent for Zocor expired on June 23, 2006; Ranbaxy Laboratories (at the 80-mg strength) and Teva Pharmaceutical Industries through its Ivax Pharmaceuticals unit (at all other strengths) were given approval by the FDA to manufacture and sell simvastatin as a generic drug with 180-day exclusivity. Dr. Reddy’s Laboratories also has a license from Merck & Co. to sell simvastatin as an authorized generic drug.

Ezetimibe/simvastatin is a combination product to lower lipids and marketed as Vytorin.

Common side effects (>1% incidence) may include abdominal pain, diarrhea, indigestion, and a general feeling of weakness. Rare side effects include joint pain, memory loss, and muscle cramps. A type of DNA variant known as a single nucleotide polymorphism (SNP) may help predict individuals prone to developing myopathy when taking simvastatin; a study ultimating including 32,000 patients concluded that carriers of one or two risk alleles of SNP rs4149056 were at 5x or 16x increased risk, respectively.