Gedeon Richter Plc v Bayer Schering Pharma AG

For added matter, a patent may make express what was implicit in the application as filed, but may not introduce an obvious conclusion which the skilled reader would merely derive from that disclosure. The court must also guard against impermissible intermediate generalisation. For obviousness, the statutory test remains decisive. Structured analyses are aids to fact-finding, not substitutes for that test. A step is not obvious merely because it is worth investigating. Where success depends on experiments, the court asks whether each proposed step was obvious and whether the overall analysis avoids hindsight. An immediate-release formulation was not obvious where acid-degradation evidence gave no fair expectation that the drug would retain the near-certain efficacy required of a low-dose contraceptive.

Gedeon Richter Plc sought revocation of Bayer Schering Pharma AG’s European Patent (UK) Nos 1,380,301 and 1,598,069, concerning pharmaceutical combinations of ethinylestradiol and drospirenone. The challenges alleged added matter and lack of inventive step over Oelkers, Krause I, Krause III and Lachnit. The patents claimed dosage ranges and, in different claims, rapid dissolution, surface coating of inert carrier particles and spraying. The central issues were whether the claims extended beyond the Parent Application, how the dissolution test affected construction, and whether the claimed formulations were obvious to the skilled pharmaceutical team.

1. Construction. The claims were construed according to what the skilled person would understand the language to mean, applying Kirin Amgen v TKT [2005] RPC 9. A claim requiring a specified in-vitro dissolution test was not implicitly limited to formulations without an enteric coating. Any formulation satisfying the test and the other claim features would fall within the claim.
2. Added matter. Under section 72(1)(d) of the Patents Act 1977, the question was whether the granted disclosure extended beyond the application as filed. The Parent Application taught that good bioavailability could be obtained by any formulation producing rapid dissolution; micronisation and spraying were examples, not exclusive methods. Making that implicit teaching express did not add matter. Deleting the reference to a 3 mg tablet altered the technical disclosure of the dissolution test and added matter. The objection was cured by the conditional amendment. The remaining objections failed.
3. Obviousness. The structured approach in Pozzoli v BDMO [2007] FSR 37 was only a guide to applying the statutory test. The court considered the skilled team, common general knowledge, inventive concept, differences from the prior art and whether the necessary steps were obvious without hindsight. An obvious-to-try argument required a fair expectation of success. Oelkers did not disclose a formulation. Acid-stability evidence, gastric variability and the need for near-certain contraceptive efficacy made an immediate-release formulation insufficiently predictable. It was not obvious to proceed to animal testing of that formulation. Krause I and III would not ordinarily have been found and reviewed by the skilled formulator and, in any event, did not provide a sufficiently clear basis for expecting success.
4. Claims 1 and 7 of the 301 patent and claim 6 of the 069 patent were not invalid for obviousness. Claims 1 and 19 of the 069 patent were invalid for obviousness over Oelkers and Lachnit, although claim 19 would survive if made dependent on claim 6. Subject to amendment dealing with the 3 mg point, neither patent was invalid for added matter.