Procedure for the purification of hyaluronic acid and fraction of pure hyaluronic acid for ophthalmic use
CA 2084875 C · Owner: Fidia S.P.A. · Inventors: Lorenzi, Silvana; Romeo, Aurelio
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A highly pure fraction of hyaluronic acid is disclosed which is non-inflammatory and avoids post-operative complications in ocular surgery. Also disclosed is a process for the preparation of hyaluronic acid characterized by converting hyaluronic acid into a corresponding quaternary ammonium salt and following purification procedures, reconverting the quaternary ammonium salt into a sodium salt of hyaluronic acid.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed April 16, 1992 and granted January 6, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 16, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 16, 2014.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
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Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.