Medicis Pharmaceutical Corporation, a US-based skincare drug manufacturer, has filed a lawsuit against Daiichi Sankyo-owned Ranbaxy Pharmaceuticals for alleged infringement of its patent on Solodyn, a minocycline hydrochloride extended-release tablet used to treat acne.
According to drug sales tracking agency IMS, Solodyn — which accounts for about half of the revenues of Medicis Pharmaceutical — recorded sales of $365 million in the US for the year-ended January 31, 2009.
A Ranbaxy spokesperson refused to comment on the issue.
In its petition filed at the District Court of Delaware, US, Medicis alleged Ranbaxy had violated one or more claims of its US patent number 5,908,838 for the method of treatment for acne. Ranbaxy filed a marketing application (abbreviated new drug application, or ANDA) with the US Food and Drugs Administration (FDA), challenging the patent on this drug with a Para IV certification, which indicates a patent challenge.
Such litigations are common in the US. An innovator has to sue an ANDA filer with Para IV certification within 45 days of the intimation and to direct the FDA from not approving the drug before patent expiry or for the next 30 months. Normally, companies prefer out-of-court settlements rather than continuing the litigation.
Analysts said Ranbaxy was unlikely to gain much from the sale of this drug, as Israel-based drug maker Teva Pharmaceuticals was the first to challenge the patent on minocycline hydrochloride extended-release tablets in 45 mg, 90 mg and 135 mg strengths. Medicis Pharmaceutical and Teva settled their litigation out-of-court in March this year. Under the settlement, Teva can market its generic version beginning November 2011, when the patent on Solodyn expires with a 180-day marketing exclusivity.
Ranbaxy has several of such first-to-file ANDAs, including for Pfizer’s Lipitor, the world’s largest selling drug with over $12-billion sales. The out-of-court settlement with Pfizer allowed Ranbaxy to introduce a generic version of the cholesterol drug in November 2011 with six-month exclusivity.
