Amgen vs Sandoz Case: Claim Analysis

Case Summary:

Current case revolving around Amgen's drug Enbrel. Sandoz is currently creating a biosimilar for Enbrel, and is in Phase 3 of drug trials. Next step is launch, but Amgen is utilizing its Enbrel patents and method/manufacturing process to prevent Sandoz's biosimilar from launching in market.

Summary of Patents (only 3/5 are related to case)

1. The ’182 patent is said to cover the etanercept fusion protein --> main protein in Enbrel
2. The ’522 patent is said to cover constructs and methods of making the fusion protein.
3. The other patents are said to “claim methods of using etanercept to treat psoriasis and/or psoriatic arthritis.”

Claim Analysis for Patent: 8,063,182

Link: http://www.google.com/patents/US8063182

1. A protein comprising

(a) a human tumor necrosis factor (TNF)-binding soluble fragment of an insoluble human TNF receptor, wherein the insoluble human TNF receptor (i) specifically binds human TNF, (ii) has an apparent molecular weight of about 75 kilodaltons on a non-reducing SDS-polyacrylamide gel, and (iii) comprises the amino acid sequence LPAQVAFXPYAPEPGSTC (SEQ ID NO: 10); and

(b) all of the domains of the constant region of a human immunoglobulin IgG heavy chain other than the first domain of said constant region;

Within the patent application, one sees how there are a lot of DNA sequences and Amino Acid sequences - essentially what make up a protein. When looking at claim #1, part a is divided into 3 sections.

• The insoluble human TNF receptor --> specifically binds to human TNF
• the patent isn't valid for the receptor binding to something else
• the insoluble human TNF receptor --> weighs about 75 kilodaltons
• the patent is only for this specific receptor when it weights about this much
• the insoluble human TNF receptor --> amino acid sequence LPAQVAFXPYAPEPGSTC 
• thus if this specific receptor, has this sequence, the patent holds. In biological terms, it would be near impossible to create the same receptor with a diff AA Sequence. However, it is possible to create a receptor that may do a similar function.
• b) The patent only applies if the  protein binds to IgG heavy chain regions, except first. Hence, patent is only valid for this specific antibody.