US court halts launch of Dr Reddy's anti-allergic drug Allegra D24

In a major setback to Dr Reddy's Laboratories, a US court has granted a motion seeking a preliminary injunction to block the launch of its generic version of Sanofi-Aventis' anti-allergic drug, Allegra D24.

According to DRL, it intended to appeal against the verdict, delivered yesterday by the US District Court of New Jersey. In a statement, DRL said it ''strongly disagrees with the court's decision''.

Analysts were expecting the company to stand to net about $150 million in revenues from the drug in the US. It was planning to launch it 'at-risk' in the first quarter of 2011, as a patent litigation is pending in the US court between it and Sanofi-Aventis.

With an 'at-risk' launch of a generic drug, the generic company is liable to pay damages to the innovator in the event it loses the patent litigation. Dr Reddy's is said to be the only company to have received approval for the drug.

The company's generic was approved by the US Food and Drug Administration (FDA) in March, following expiry of the 30-month automatic stay associated with patent litigation in the US. According to US rules for sale of generic drugs, innovators are required to sue patent challengers within 45 days of the receipt of a patent challenge notification, to prevent approval of the drug by the drug regulator for the next 30 months, before the patent expiry or till a court gives its judgment.

The US market for Allegra D24 (fexofenadine hydrochloride/pseudoephedrine hydrochloride 180 mg/240 mg extended release tablet) is about $180 million.