Ranbaxy Laboratories' wholly owned subsidiary, Ranbaxy (UK) Limited (RUKL), successfully overcame a court action brought in the UK by Abbott Laboratories (Abbott) to prevent Ranbaxy from selling immediate release Clarithromycin (tablets, 250 mg and 500 mg and suspension 125mg/ 5ml & 250mg/5ml) in the UK market.

In making its ruling in favour of Ranbaxy's arguments that the asserted patent was invalid on various grounds, the Court agreed that the specific patent claims asserted by Abbott were invalid and characterized it as "a weak patent." Abbott was refused leave to appeal. Following the Court's ruling, Ranbaxy has launched Clarithromycin in the UK, Ranbaxy said in a release.

Clarithromycin, a macrolide antibiotic, is used in the treatment of common bacterial infections, such as upper and lower respiratory tract and skin or skin structure infections. Clarithromycin is also used in the treatment of Mycobacterium Avium Complex (MAC) in HIV patients and toxoplasmosis. The market in the UK for immediate release Clarithromycin, both in tablet and suspension form is currently worth £ 13.5 million [IMS Sept 2004 MAT].

Clarithromycin was covered by a first generation patent, which expired in the UK on 19 November 2004. Abbott also had a second generation patent which claimed, amongst other things, solvent free Clarithromycin Form II, however made.

Strongly upholding the company's position, Jay R Deshmukh, VP, Global Intellectual Property, Ranbaxy, said, "In interim injunction proceedings, Ranbaxy was confident that Abbott's patent should be held invalid and so took the unusual step of filing for summary judgment at the interim proceedings."

Ranbaxy had already received approval from the Medicines and Healthcare products Regulatory Agency (MHRA), UK, to manufacture and market Clarithromycin tablets, 250 mg and 500 mg and suspension 125mg/ 5ml & 250mg/5ml. The MHRA determined the Ranbaxy formulations to be bio-equivalent and to have the same therapeutic effect as that of the drug, Biaxin (also known as Klaracid) of Abbott, the release added.

Based in London, RUKL is a wholly owned subsidiary of Ranbaxy Laboratories Ltd, India. Having established operations in the UK in 1996, RUKL is now ranked 8th in the UK generic market.