The lawsuit, filed with the US District Court of Delaware, calls for injunctive relief and damages for breach of patents covering biologically active polypeptide fusion compositions and their production methods.
One of BMS's products that allegedly violates the patents is Orencia, which suppresses inflammation-causing immune system cells, or cytokines, and is new to the treatment of rheumatoid arthritis, a disease that afflicts almost 3m Americans and has created a global market for innovative drugs projected to reach $10bn (€8.4bn) by 2008.
"We have a number of patents on fusion protein technology, which we believe are being infringed by Bristol-Myers Squibb," said ZymoGenetics CEO Bruce Carter.
"It is important that ZymoGenetics protect its intellectual property rights for technology that it expended significant resources in developing, and we will enforce our patents through litigation when necessary."
Immunoglobulin fusion proteins are proteins that are produced using recombinant DNA technology whereby a portion of an antibody, a heavy chain constant domain for example, is combined with the portion of a second protein, typically the portion of a cell-surface receptor that is responsible for binding to a growth factor.
In-PharmaTechnologist.com approached BMS, which said it would not comment on ongoing litigation.
One of the patents in question pertains to biologically active, dimerised polypeptide fusion, comprising first and second polypeptide chains, in which each of the polypeptide chains consists of a non-immunoglobulin polypeptide requiring dimerisation for biological activity joined to a dimerising protein heterologous to said non-immunoglobulin polypeptide.
The other method is for producing a secreted, biologically active dimerised polypeptide fusion.
It involves introducing into a eukaryotic host cell a DNA construct comprising a transcriptional promoter operatively linked to a secretary signal sequence followed downstream, by and in proper reading frame, with a DNA sequence encoding a non-immunoglobulin polypeptide requiring dimerisation for biological activity, joined to a dimerising protein.
The host cell is then grown in an appropriate growth medium under physiological conditions to allow the secretion of a dimerised polypeptide fusion which is the isolated.
Amgen and Regeneron have already licensed the use of ZymoGenetics' patented fusion protein technology.