Bristol-Myers Squibb’s CTLA4Ig Formulation Patent Survives IPR Obviousness Challenge from Momenta Pharmaceuticals

Momenta v. BMS

January 3, 2016

MOMENTA PHARMACEUTICALS, INC. (Petitioner)
v.
BRISTOL-MYERS SQUIBB COMPANY (Patent Owner)

Case IPR2015-01537
Patent 8,476,239
FINAL WRITTEN DECISION
December 22, 2016

The PTAB concluded that the preponderance of the evidence did not support Momenta’s argument that the challenged claims would have been obvious.

The claims of Patent US 8,476,239 are directed to stable liquid formulations of the therapeutic molecule CTLA4Ig.  CTLA4Ig is a protein molecule that is used to treat immune system diseases and disorders such as rheumatoid arthritis and adverse transplant reactions.

Claim1:  A stable formulation suitable for subcutaneous administration comprising:
[1]  at least 100mg/ml CTLA4Ig molecule,
[2]  a sugar selected from the group consisting of sucrose, lactose, maltose, mannitol and trehalose and mixtures thereof and
[3]  a pharmaceutically acceptable aqueous carrier, wherein the formulation has a
[4]  pH range of from 6 to 8 and
[5]  a viscosity of from 9 to 20 cps, and
[6]  the weight ratio of sugar:protein is 1.1:1 or higher.
(Bracketed numbers added)

Momenta argued that the inventors did “nothing more than the efforts of a skilled formulator choosing from a limited set of known formulations to subcutaneous liquid formulations.” Momenta further argued that “the inventors went to the formulator’s toolbox and tried the first line of excipients and formulation parameters.  And they worked.” The PTAB agreed that the prior art references provided general guidance for formulating proteins as stable liquids and that BMS followed certain aspects of those general teachings when creating its stable liquid formulation comprising CLTA4Ig, a known protein.  Momenta’s cited evidence, however, did not persuade the PTAB that an ordinarily skilled artisan would have reasonably expected to be successful in achieving the claimed formulations. The evidence was not persuasive because, despite the prior art teaching of general guidance for formulating proteins as stable liquids, the prior art also taught that maintaining physical and chemical stabilities for most proteins in aqueous solution for an extended period is extremely difficult. Expert testimony about testimony about routine trial-and-error optimization did not overcome the statements of difficulty. Such statements of difficulty in the art indicated to the PTAB that there would not have been a reasonable expectation of success in achieving the claimed formulations.

The PTAB highlighted in the importance of anticipated success and predictable results in determining obviousness. Citing the U.S. Supreme Court:

When there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp.  If this leads to the anticipated success, it is likely the product not of innovation but of ordinary skill and common sense.  In that instance the fact that a combination was obvious to try might show that it was obvious under § 103. KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 421 (2007) (emphasis added); compare Merck & Co. v. Biocraft Labs., Inc., 874 F.2d 804, 809 (Fed. Cir. 1989) (“Reached by means of routine procedures, and producing only predictable results, the recited dosages therefore do not distinguish the claims of the ’430 patent from the amiloride/hydrochlorothiazide combination that the district court properly found was disclosed in the ’813 patent.” (emphasis added)).

Links:

PDF of Final Decision (IPR2015-01537)

Update 1/9/2017 – Link to Jones Day Blog:
“Routine Trial-and-Error Approach to Protein Formulation Is Not Sufficient to Establish Obviousness Absent a Reasonable Expectation of Success in Achieving the Claimed Formulation”