The present decision shows that examples of patent applications should be drafted with care. Errors may prove fatal to the patent as a whole, as the patent proprietor had to learn in this case.
Claim 1 of the main request read:
A process for the production of microspheres containing pancreatic lipase or mixtures thereof with other pancreatic enzymes, one or more hydrophilic low melting polymers, and optionally excipients for pharmaceutical use, said microspheres having diameter comprised between 10 µm and 1500 µm and enzymatic title equal to or higher than 90% of the title of the solid mixture of their components, characterised in that a solid mixture formed by said lipase or mixtures thereof with other pancreatic enzymes, one or more hydrophilic low melting polymers, and optional excipients, is heated to a temperature equal to or higher than the melting temperature of said hydrophilic low melting polymer, in stirring condition, where said hydrophilic low melting polymer has a melting point between 20°C and 90°C.
Board 3.3.02 found this claim to be insufficiently disclosed:
[4.1] An invention is in principle sufficiently disclosed if at least one way is clearly indicated enabling the skilled person to carry out the invention over essentially the whole claimed range. The skilled person, trying to rework the invention defined in the main request, would first direct his attention to the examples, in which the invention is described in its most concrete form. The patent in suit contains four examples, of which examples 1 and 2 are reference examples and therefore irrelevant for the present invention.
Example 3 describes the preparation of pancreatin pellets using PEG 400 (polyethylene glycol) as hydrophilic low melting polymer. In view of the fact that according to document D12 PEG 400 has a melting point of 4 to 6°C, which was not contested by the respondent, example 3 is also not encompassed by the invention defined by the main request, which requires a hydrophilic low melting polymer having a melting point between 20°C and 90°C. Regarding the respondent’s argument that the reference to PEG 400 was an obvious error which the skilled person, knowing the melting point of PEG 400, would have immediately recognised as such and, as a consequence, would have understood PEG 4000 instead, the board notes that claim 1 as granted does not contain any lower limit regarding the melting point of the low melting hydrophilic polymer. The skilled person did therefore not have any reason to assume that example 3 was defective. He would rather have concluded that it was representative of the invention according to claim 1 as granted, but no longer relevant for the invention now defined in the main request. Therefore, he would have dismissed example 3 and turned his attention to example 4 in which PEG 4000 is used as low melting hydrophilic polymer.
The appellant argued that it was not possible to prepare pancreatin pellets by following the instructions given in example 4. The fact that the maximum rotation speed of the mixer-granulator Zanchetta Rotolab P-50 […] was limited to 315 rpm, so that the required 900 rpm […] was not obtainable, was offered as the principal reason for this failure. Reference was made to document D23.
The respondent counter-argued that example 4 involved two different mixers, namely a high-energy mixer-granulator Zanchetta Rotolab with a maximum rotation speed of 1150 rpm, mentioned in paragraph  of the contested patent, and a mixer-granulator Zanchetta Rotolab P-50 depicted in paragraph  of the contested patent. Paragraphs  and  related to two separate procedures involving two different mixers. As a consequence, the appellant, having erroneously used the mixer-granulator Zanchetta Rotolab P-50 for both procedures, had not correctly reworked example 4, so that document D23 was completely irrelevant.
However, the fact that paragraphs  and  relate to two separate procedures involving two different mixer-granulators is a piece of information which the skilled person is not able to extract from the wording of example 4. Paragraph  describes the preparation of pancreatin pellets involving the steps of placing pancreatin and PEG 4000 in the tank of a high-energy mixer-granulator Zanchetta Rotolab, processing the mixture under the specific conditions described therein and finally unloading the pellets thus obtained. Then, at the beginning of paragraph , example 4 continues with the wording “Using the described process, with a mixer-granulator Zanchetta Rotolab P-50 spherical pellets are obtained which are afterwards coated with a gastroresistant membrane formed by HP-55, triethylcitrate and talc.” The skilled person, reading example 4 as a whole, would necessarily assume that the same mixer-granulator is used, in the sense that the high-energy mixer-granulator Zanchetta Rotolab according paragraph  is a generic denomination of the apparatus which is then specifically defined as mixer-granulator Zanchetta Rotolab P-50 in paragraph . Confronted with the problem that the mixer-granulator Zanchetta Rotolab P-50 does not allow a rotation speed of 900 rpm, he would conclude that example 4 was not enabling, as either said rotation speed of 900 rpm or the designation of the mixer-granulator Zanchetta Rotolab P-50 was incorrect.
Sufficiency of disclosure must be assessed on the basis of the patent as a whole. As a consequence, the absence of enabling examples does not necessarily mean that the claimed invention is not sufficiently disclosed. If, however, as in the present case, where the process in question involves the processing of an instable enzyme under relatively harsh conditions (high rotational speed, elevated temperatures) without any significant loss of its activity, the claimed invention is of a complex nature, then the skilled person is in need of clear and precise instructions. These are lacking, on account of the deficiencies in examples 3 and 4 mentioned above. Trying to carry out the invention only on the basis of the general teaching of the description would, taking into account the technical complexity of the present case, amount to an undue burden. As a consequence, the requirements of A 83 are not met.
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