The Indian patent office has revoked a patent granted to Germany's Boehringer Ingelheim for pulmonary disease treatment drug Spiriva following Cipla's opposition, the Indian drug major said today.
"Based on a Post Grant opposition filed by Cipla, the Indian Patent Office recently revoked a patent granted to Boehringer Ingelheim for Tiotropium Bromide Monohydrate (crystalline salt)," Cipla said in a statement.
Boehringer Ingelheim (BI) sells Tiotropium Bromide Monohydrate under the Spiriva brand.
Cipla has been marketing the generic version of Tiotropium Bromide Monohydrate under the brand name 'Tiova' since 2003. The product is available in inhalers and rotocaps.
Although Tiotropium Bromide Monohydrate is a molecule which was patented prior to January 1995, BI filed for a patent for the crystalline salt of Tiotropium Bromide Monohydrate on the grounds that it is more stable, it added.
"Initially, the Patent Office granted the patent but on our filing a post grant opposition, the decision to grant the patent was reversed," Cipla said.
Comments from Boehringer Ingelheim could not be immediately obtained as a emailed query remained unanswered.
The Indian Patents Act clearly excludes grant of patents to molecules invented before January 1995. Also, under Section 3(d) of the Patents Act, the law bars grant of patents to salts, esters etc of substances invented before January 1995 unless efficacy is significantly enhanced, Cipla said.
The order of the patent office to revoke the patent follows the judgement of the Supreme Court of India in Cipla versus Novartis case in 2013 in which the apex court dismissed the plea of Novartis AG for patent of its cancer drug Glivec.
The Supreme Court had held that efficacy has to be proved in the context of therapeutic efficacy.
Following the launch of Tiova, Cipla has also introduced two more combination drugs Tiotropium + Formoterol under the brand name 'Duova' and Tiotropium + Formoterol + Ciclesonide under the brand name 'Triohale', the company said.
