Glenmark cannot launch ezetimibe (Zetia) generic till it clears patent dispute with Schering

Glenmark expects 180-days marketing exclusivity, if its ezetimibe genericanti-cholesterol drug gets final FDA approval.

A generic version of anti-cholesterol treatment ezetimibe (Zetia) from Glenmark Pharmaceuticals has got tentative approval from the US FDA.

However, Glenmark cannot launch generic ezetimibe in the US market, till it is cleared out of the patent infringement suit filed against it by Schering-Plough.

Ezetimibe (Zetia) is the original drug from Schering Plough and MSP Singapore Company LLC.

Ezetimibe (Zetia) generic is the first generic version of the anti-cholesterol drug, the company’s US subsidiary Glenmark Generics said.

Glenmark has the first-to-file status on ezetimibe tablets. This gives ezetimibe (Zetia) giving it a potential of 180-days of marketing exclusivity.

Zetia is the world’s fourth-most prescribed cholesterol drug. Zetia achieved sales of $1.5 billion in 2008.

Zetia prescriptions accounted for 8.4 percent of the total cholesterol-drug market a year back, according to Bear Stearns & Co. analyst John Boris. Zetia was approved by regulators in 2002.

Schering-Plough markets the anti-cholesterol drug with Merck & Co and the companies split the revenue.

If Glenmark gets 180-day exclusivity, the company would have the earliest opportunity among any competitors to gain market share from the branded product.

However, ezetimibe (Zetia)  product launch is dependent upon receipt of final approval of its Abbreviated New Drug Application, or ANDA from the US FDA and resolution of litigation currently pending in the US district court of New Jersey, the company said in a release.

New Jersey-based Schering-Plough on March 2007 sued Glenmark to block regulatory approval of a generic version of Zetia. Glenmark’s  generic would infringe a patent it owns on the medicine, whose key ingredient is ezetimibe, Schering-Plough said.

Zetia works differently than rivals such as Merck’s Zocor or Pfizer Inc.’s Lipitor, blocking absorption of cholesterol from food in the digestive tract rather than the liver.

Zetia is a new kind of cholesterol-lowering drug. Unlike the other cholesterol-lowering drugs, Zetia acts by diminishing the absorption of dietary cholesterol through the intestines.

Zetia may be taken alone or with a statin drug. Because the two drugs fight cholesterol in different ways, the Zetia/statin combination has a greater impact than either drug alone.

Cholesterol—especially “bad” LDL cholesterol—promotes clogged arteries, increasing the risk of heart attack and stroke. “Good” HDL cholesterol helps to prevent clogged arteries. Zetia lowers the bad cholesterol and raises the good. It also lowers total cholesterol readings and reduces levels of triglycerides (fats in the blood).

Glenmark filed an ANDA with the USFDA approval for generic version of ezetimibe on October 25, 2006. Glenmark’s ANDA included a Paragraph IV certification with respect to patents listed by Schering The company will also be vertically integrated by manufacturing the active pharmaceutical ingredient for its Ezetimibe tablets.

Currently, Glenmark has around 40 generic products authorized for distribution in the US market. Glenmark has filed over 40 ANDAs  with the US FDA pending approval.