Avandia® Patents Afford Protection Against Generic Competition

SYDNEY, Australia, Sep 8, 2006 – Generic pharmaceutical manufacturers should proceed with caution when developing generic versions of Avandia®, (Rosiglitazone maleate), according to experts at GenericsWeb. Analysis of their Pipeline Patent Intelligence reveals that the patent situation surrounding this product is very complex, and is likely to be problematic for lesser-informed generic developers, especially those developing for multiple markets.

GlaxoSmithKline’s (GSK) oral medicine Avandia® is indicated to treat type 2 diabetes and belongs to the group of thiazolidinedione anti-diabetes compounds, otherwise known as the glitazones. Sales for Avandia® in 2005 were £1.15 billion (source: GSK).

Although Supplementary Protection Certificate (SPC) extensions on the ‘base’ patent, which protects the active ingredient, expire in Europe in 2013, a maleate salt patent for Rosiglitazone offers additional protection until 2014, also by virtue of SPC extensions.

Whilst in the US, a number of patents offer protection of the base compound and the product’s indicated use until 2017, however a much broader patent protecting all salts is due to expire in 2014. “The difference in patent examination practices around the world is highlighted by this example, in which the equivalent European application seeking to protect all salts was refused by the EPO,” says Leighton Howard, Managing Director of GenericsWeb.

Teva and Ranbaxy appear to be proactively addressing these patent examination discrepancies, having recently filed Abbreviated New Drug Applications (ANDA) with Paragraph IV certifications in the US.

Further analysis of the comprehensive patent search found in the Rosiglitazone Pipeline Developer report reveals that many alternative salts to the maleate are already patent protected, whilst numerous patents protect possible polymorphic forms of the maleate salt. Over 50 patent families relating to specific molecular forms of the Rosiglitazone active ingredient have been identified, with more being published every month.

“This is an extraordinarily high number of patents in this category and is likely to cause concern for all but the most proactive generic competitors,” says Mr Howard. “For those generic developers who have not yet considered their course of action for this product, pending examination of GSK’s patent filings combined with a corresponding increase in patent activity by generic competitors demonstrates the need for regular, comprehensive monitoring of both old and new applications to take advantage of any non-infringing routes remaining in this patent minefield,” he continued.

Three patent families are listed in the US FDA Orange Book, however the Pipeline Developer identifies over 180 patent families relevant to Rosiglitazone molecular forms, processes for it’s preparation, formulations, uses and administration thereof. Again, this stresses that non-infringing Rosiglitazone generic pharmaceuticals should only be considered after an in-depth analysis of the results of a comprehensive patent search such as those found in the GenericsWeb Pipeline Developer report.

About GenericsWeb

GenericsWeb Pipeline Patent Intelligence provides unrivalled patent knowledge required to navigate your generic drug development with confidence, all at the click of a button. For further information about GenericsWeb Pipeline Patent Intelligence, contact Jesse Tale at j.tale@genericsweb.com or call +61-2-98186111.

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