A road map for patent obviousness

January 03, 2018
Patterson Thuente IP

It probably comes as no surprise that inventions that are obvious aren’t eligible for patents. Yet arguments over obviousness land in the court all the time. A recent ruling by the Federal Circuit Court of Appeals (which hears all patent-related appeals) in Millennium Pharmaceuticals, Inc. v. Sandoz Inc. illustrates several arguments that can arise when the obviousness of an invention — and therefore the validity of its patent — is at issue.

Contested findings

Millennium Pharmaceuticals is the exclusive licensee of a patent for a lyophilized (freeze-dried) compound, an ester of bortezomib and D-mannitol, used to treat multiple myeloma. Bortezomib is the subject of an earlier patent but never received approval from the Food and Drug Administration (FDA) or market status because of its instability and insolubility. The ester compound has dramatically improved dissolution and stability.

Several defendants, including Sandoz Inc., sought FDA approval of a generic version of the ester compound, alleging that the patent was invalid based on obviousness. In the litigation that ensued, the district court agreed with the defendants. Millennium appealed to the Federal Circuit.

Under the microscope

The primary issue was whether a person of ordinary skill — seeking to remedy the instability and insolubility and produce an effective bortezomib formulation — would obviously produce the ester compound. Sandoz provided no references (or “prior art”) that showed or suggested a reason to make the ester, and no reference taught or suggested that such a new compound would have the long-sought properties of stability and solubility. The appellate court thus found that Sandoz had failed to show it was obvious to use mannitol to make an ester during lyophilization or that it would solve bortezomib’s problems.

The appeals court determined, too, that the district court had erred in finding that lyophilizing bortezomib with mannitol to form an ester was a suitable option that the prior art (such as the bortezomib patent) didn’t discourage persons of ordinary skill from pursuing. It found persuasive evidence that the process would have been unattractive to persons of ordinary skill because it could disturb the chemical properties that make bortezomib effective at fighting cancer.

The Federal Circuit also criticized the district court for its consideration of “inherency” — the idea that a patented claim was inherent in prior art. The appellate court noted that no experts testified that they foresaw, expected or would have intended the reaction between bortezomib and mannitol or that the resulting ester would have the long-sought properties and advantages.

Another round of evidence

The appellate court also faulted the district court for its evaluation of the objective indications of nonobviousness (also known as secondary considerations). Such evidence, it emphasized, can represent the strongest evidence in the court record. The court emphasized that examination of secondary considerations includes two particular indications:

Unexpected results. The district court had declined to consider the ester’s advantages and benefits over bortezomib, ruling that bortezomib wasn’t the closest prior art. But the appellate court found that bortezomib was indeed the closest prior art and that the ester exhibited unexpected results compared with it, with greatly improved stability, solubility and dissolution.

Long-felt need. Evidence of long-felt need is a particularly strong indicator of nonobviousness when it demonstrates both that a demand existed for an invention and that others tried but failed to satisfy the demand. The appellate court said that the long-felt need for a drug to treat multiple myeloma was undisputed; prior treatments gave poor remission and low survival rates.

Formula for success

The Federal Circuit ultimately reversed the district court’s finding of patent invalidity. Its heavy criticism of the initial ruling provides a useful road map of how parties should expect a court to analyze obviousness arguments and evidence. 

Millennium Pharmaceuticals, Inc. v. Sandoz Inc., No. 2015-2066, July 17, 2017 (Fed. Cir.)

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