Process for production of avermectins and cultures therefor
CA 2131284 C · Owner: Pfizer Limited · Inventors: Hafner, Edmund W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to Streptomyces avermitilis lacking branched-chain amino acid transaminase activity branched-chain, 2-oxo acid biosynthetic activity and optionally and preferably, avermectin B-O-methyl transferase activity methods for, preparation thereof, and use thereof to produce natural and non-natural avermectins from branched-chain fatty acid or branched-chain 2-oxo acid precursors. Such avermectins are useful as parasiticides.
Read the whole patent
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 November 30, 1992 and granted January 6, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 30, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 30, 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
Timeline From CIPO dates
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.