Leo Pharma v. Rea: A Step in the Right Direction

In the 2007 Supreme Court decision in KSR v. Teleflex,1 the Court struck down the rule previously used by the U.S. Patent and Trademark Office (USPTO) that to combine references to support an obviousness rejection of a claim of a patent application under 35 U.S.C. §103, a patent Examiner must identify an explicit suggestion in the prior art to make the asserted combination of references. Since this decision, many patent attorneys prosecuting patent applications before the USPTO have been frustrated by Examiners fashioning obviousness rejections by combining portions of different prior art references and providing only cursory, vague, and sometimes dubious rationales for why a person of ordinary skill in the relevant art would have been motivated to have made the asserted combination. The case of Leo Pharmaceutical Products, Ltd. v. Rea2 (Leo Pharma), decided in August 2013 in the Court of Appeals for the Federal Circuit (CAFC), serves as a reminder to the Examiner Corps that an Examiner must identify a convincing reason why a person of ordinary skill in the relevant art would have been motivated to have made an asserted combination.

Leo Pharma involved U.S. Patent No. 6,753,013 (the ‘013 Patent), directed to a composition for the treatment of skin conditions, such as psoriasis. The ‘013 Patent was invalidated under 35 U.S.C. §103 in light of three prior art references in a reexamination proceeding in the USPTO. The ‘013 patent included claims reciting a non-aqueous “storage stable” combination of vitamin D and a corticosteroid for the topical treatment of skin conditions. The use of a corticosteroid and vitamin D to treat skin conditions was previously known, however, the two compounds had previously needed to be stored and administered separately. The corticosteroid and vitamin D were stable under different pH conditions, and previous efforts to combine the two into a single treatment compound resulted in the corticosteroid, the vitamin D, or both to quickly chemically degrade. The inventors of the compound claimed in the ‘013 patent had discovered a combination of the corticosteroid, the vitamin D, and a class of solvents, which was storage stable and did not chemically degrade.

During the reexamination proceeding, the USPTO invalidated the claims of the ‘013 patent under 35 U.S.C. §103 in light of a 1977 patent to Turi, which disclosed a nonaqueous combination of a steroid and a solvent recited in the claims of the ‘013 patent, a 1984 patent to Dikstein disclosing a combination including vitamin D, corticosteroid, propylene glycol, and almond oil, and a 1993 patent to Sterup disclosing an aqueous combination including vitamin D, a steroid, propylene glycol, and almond oil. Dikstein and Sterup described the disclosed compositions as displaying “surprising” advantageous results. The USPTO asserted that it would have been obvious to have modified the compositions of Dikstein or Sterup to include the solvent disclosed in Turi or to have modified the composition of Turi to include vitamin D.

The CAFC disagreed with the USPTO and reversed the invalidation of the ‘013 patent. The CAFC concluded that the USPTO had not established that a skilled artisan would have found any motivation to have modified Dikstein or Sterup in view of Turi. The CAFC found that neither Dikstein nor Serup recognized or addressed the stability problem solved by Leo, and in fact, the composition disclosed in Dikstein and Serup included compounds, such as almond oil and propylene glycol, which actually accelerated the breakdown of the vitamin D and/or steroid. Since neither Dikstein nor Serup recognized the stability problem, and in fact described the disclosed compounds as being surprisingly effective, upon a reading of these references a skilled artisan would not have been motivated to have modified the disclosed compositions in light of Turi. The CAFC found that the alleged motivation presented by the USPTO to combine Dikstein or Sterup with Turi was based upon hindsight analysis guided by Leo’s recognition of the stability problem of the disclosed compositions.

The CAFC found that the USPTO had failed to give proper weight to Leo’s identification of the problem solved by the claimed composition – that a stable skin treatment compound including vitamin D and corticosteroid should be designed. The CAFC found that the prior art did not recognize the stability problem of compounds, including both vitamin D and a corticosteroid, but rather “either discouraged combining vitamin D analogs and corticosteroids … or attempted the combination without recognizing or solving the storage stability problems.” Leo also presented evidence that experts discouraged combining vitamin D and corticosteroids because of stability problems.

The CAFC also noted that Turi was available for 22 years prior to Leo’s patent application was filed, yet there was no evidence that anyone had attempted to improve the compound disclosed in Turi by adding vitamin D. Further, the CAFC noted that although the claims of the ‘013 patent recited a composition including a class of solvents, there were a virtually infinite number of potential additives available to try to form a storage stable combination of corticosteroid and vitamin D, and the USPTO did not offer any specific reason why the solvents recited in the ‘013 patent would have been particularly obvious to try.

The CAFC further found that objective indicia of non-obviousness weighed in favor of the patentability of Leo’s claimed compound. The compound exhibited unexpected results – the Dikstein and Serup formulations worked poorly, even when a solvent as disclosed in the ‘013 patent was added, solved a long felt but unsolved need – the need for a single composition for the treatment of psoriasis, and exhibited commercial success – the commercial embodiment of the compound claimed in the ‘013 patent was the first FDAapproved drug to combine vitamin D and corticosteroids into a single formulation for topical application. The objective indicia of obviousness outweighed the USPTO’s hindsight based finding of obviousness of the claimed compounds.

In summary, Leo Pharma emphasizes the requirement that the Examiner provide a reasonable rationale why a skilled artisan would have made an asserted combination. The motivation for the asserted combination cannot be based on hindsight analysis gleaned from the disclosure of the patent or application under examination. Further, objective indicia of non-obviousness must be given proper weight in a determination of obviousness.

1127 S.Ct. 1727 (2007)
22013 WL 4054937 (Fed. Cir. 2013)