Friday 11 September, 2009

Oxaliplatin (Eloxatin) injection: CAFC construed key patent’s claim broadly; decision favorable to innovator Sanofi

In a significant decision, The Court of Appeal for Federal circuit (CAFC) has rejected the claim construction of U.S. District Court for the District of New Jersey (decision by Judge J.A. Pisano) on key patent covering anti-cancer parenteral formulation of Oxaliplatin (Eloxatin). Earlier, the district court has granted summary judgment of non-infringement in favor of various generic players like Sandoz, Teva and Mayne Pharma (Hospira) on Oxaliplatin (Eloxatin) 50 mg/vial, 100 mg/vial, 200 mg/vial and 5 mg/ml injection.


Following patents are listed in Orange Book for Oxaliplatin (Eloxatin) 50 mg/vial, 100 mg/vial, 200 mg/vial and 5 mg/ml injection:


US5338874 (Expiry: Apr 07,2013): Which covers Optically pure cis-oxalato (trans- 1-1,2-cyclohexanediamine) Pt(II) wherein the melting point thereof is between 198C and 292 C

US5420319 (Expiry: Aug 08,2016): Which covers a Cis-oxalato(trans-1-1,2-cyclohexanediamine) Pt(II) complex having high optical purity represented by Formula 1 which possesses optical purity of 99.94% or more and a melting point between 198.3.degree. C. and 199.7.degree. C

US5716988 (Expiry: Aug 07,2015) : Which covers a pharmaceutically stable preparation of oxaliplatinum for the administration by the parenteral route, consisting of a solution of oxaliplatinum in water at a concentration of 1 to 5 mg/ml and having a pH of 4.5 to 6, the oxaliplatinum content in the preparation being at least 95% of the initial content and the solution remaining clear, colorless and free of precipitate after storage for a pharmaceutically acceptable duration of time.

US5290961 (Expiry Jan 12, 2013): Which covers a process of preparing a cis-platinum (II) complex of a 1,2-cyclohexanediamine isomer.


Sanofi-Aventis filed suit against Mayne Pharma (Hospira), Teva and Sandoz in June-July 2007 and their API supplier W.C. Heraeus GmbH in May 2008, for infringement of US5338874, which covers Oxaliplatin as product.


The District court's decision

The U.S. District Court for the District of New Jersey in it’s decision (on June, 2009) opined that although ‘874 patent covers optically pure oxaliplatin as product, however, the claim construction clearly suggests that claim in actual should be product by process claim. Also, court concluded that process limitation of ‘874 patent is separation of isomer using HPLC technique. Importantly, generic players are not using HPLC technique for resolution of isomer. Further, court upheld the validity of the patent but concluded no infringement of claim 1 by generic players Mayne Pharma (Hospira), Teva and Sandoz.

Court of Appeal for Federal Circuit (CAFC) decision
On june 30, 2009, Innovator Sanofi and Debiopharm appealed against the district court’s decision in CAFC, wherein they questioned claim construction by district court. Subsequently, on July 10, 2009 court stayed the district court’s Judgment.


Further, on Aug 7, 2009, USFDA approved ANDA of some generic players.

The CAFC was not in agreement with the claim construction of District court and opined that prior art Kidani process produced Oxaliplatin, which was 90% pure. Importantly, the ‘874 patent produced Oxalipaltin with pharmaceutical grade purity.

Further, District erroneously limited the disputed claim to process limitation by HPLC. The district court erred in construing composition claims as product by process claims. The patent specification and prosecution history focus on the property of the composition (optical purity) and not the process used to obtain the same. The specification defines the invention as Oxaliplatin of high optical purity and not the process used to obtain that purity.

The court vacated and remanded that summary judgment opinion back to U.S. District Court for the District of New Jersey

CAFC Opinion Here


Generic player affected by this ruling: Mayne Pharma (Hospira), Teva, Sandoz, W.C Heraeus, Barr, APP pharma and Abraxis Bioscience, Actavis, Fresenius Kabi, Sun Pharma, Ebewe Pharma, MN pharma (Par)

No comments:

web page statistics
Disclaimer: "IP Pharma Doc" blog is published for information purpose only. "IP Pharma Doc" blog contains no legal advice. I assume no legal responsibility for the views/information expressed here. “IP Pharma Doc” blog is my personal website and not edited by my employer, accordingly, no part of my blog should be attributed to my employer. All information on the present blog should be double checked for its accuracy and applicability. © Dr. Sarwal (2007)
 
eXTReMe Tracker