Generic company's Detrol Polymorph Patent Highlights Ongoing Quality Issues in USPTO

A guest post by Leighton Howard

The upcoming allowance of a patent to a
generic manufacturer which essentially protects any polymorphic form of
tolterodine tartrate together with a carrier or diluent demonstrates that the
quality of patent examination at the USPTO cannot be relied upon to filter out
patent applications that are clearly not innovative from the eyes of a generic
developer and that may significantly affect the level of generic competition to
Pharmacia & Upjohn’s Detrol product post patent

GenericsWeb researches and monitors patent
publications to assist in developing generic pharmaceuticals. Although many
generics companies see this as an essential component of their development
activities, some choose to focus on Orange Book listed patents and others filed
by the innovator alone. This case clearly shows the latter option to be
deficient, representing a significant risk to less informed generic developers.
Similar cases, unfortunately, are highly likely unless the examination quality
issues at patent offices around the world are

GenericsWeb’s Pipeline Developer report for
Tolterodine identifies a PCT application entitled “Novel Polymorphs of
Tolterodine Tartrate” filed in 2003 by Hetero Drugs Ltd of Hyderabad (IN), more
than 5 years after approval of products containing Tolterodine Tartrate as a
‘white, crystalline powder’. This resulted in a corresponding US patent
application which, if granted, will ordinarily run until 2023 – more than 10
years after the molecule patent that protects (and discloses methods for making)
the Tolterodine Tartrate active ingredient per se.

A Notice of Allowability issued by the
USPTO examiner on May 18th 2007 shows that claims to ‘A
pharmaceutical composition comprising a polymorphic form of tolterodine tartrate
and a pharmaceutically acceptable carrier or diluent’ have been approved for
grant following the prosecution of this application. Claims to amorphous forms
of Tolterodine tartrate per se are also considered allowable in the same

Upon grant, which the public record shows
to be imminent, this patent is expected to prevent any company other than Hetero
from launching a generic version of Tolterodine as a tartrate salt in the USA. It could also be a cause for
concern by the innovator Pharmacia & Upjohn, whose original product
seemingly falls within the scope of the claims. Whilst the question of validity
of the allowed claims can only be answered by extensive legal scrutiny, any
experienced generic developer would be of the opinion that these claims lack any
inventive step over the originator product approval data, and are not in the
spirit of ‘innovation’ that the patent system is intended to reward. The
quality of examination at the USPTO clearly needs

Is this a fair use of the patent system?
Are generic companies just playing the innovators at their own game? Is it
possible for patent examination quality to improve?

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