T 1170/07 (Tethrahydrolipstatin for treating NIDDM/F. HOFFMANN-LA ROCHE AG) 13-03-2012

1. The appeal is admissible.

2. Admission of the new requests

2.1 Main request and auxiliary request I

These requests had initially been filed as auxiliary requests II and III with letter dated 9 February 2012 and were resubmitted as main request and auxiliary request I with letter dated 5 March 2012. They constitute a reaction to objections raised in the board's communication pursuant to Article 15(1) RPBA of 17 November 2011. They are therefore admissible (Article 13(1) RPBA).

2.2 Auxiliary requests II and III

These requests were submitted at a late stage of the oral proceedings. In view of the fact that the amendments made were simple, straightforward and foreseeable and that they did not put the opponent and sole appellant into a worse position than if he had not appealed, the board admitted them into the proceedings (Article 13(1) RPBA).

3. Main request - amendments

3.1 Substitution of "consisting essentially of" for "comprising"

Claim 1 of the main request includes a unit dosage form, which consists essentially of tetrahydrolipstatin formulated as an oral composition. Before evaluating whether the original application in its entirety specifically discloses such a unit dosage form, it first has to be established what the term "consisting essentially of", which cannot be found in the original application, means in this context.

The appellant, making reference to decision T 0468/99, argued that "consisting essentially of" meant that the claimed composition must not contain any additional components that might influence the properties of the composition, which even excluded excipients such as PVP or microcrystalline cellulose. The consequence of such an interpretation would be that the unit dosage form formulated as an oral composition would be restricted to tetrahydrolipstatin per se, as any additional compound would have some effect on the properties of the composition.

However, claims should be read in a technically reasonable way. Unit dosage forms formulated as oral compositions necessarily comprise a vehicle or carrier for the active agent, otherwise a safe administration of the active agent is not possible. This requires the presence of further compounds or excipients, which, as was mentioned above, have an influence on the properties of the composition in terms of release rate, stability etc. As a consequence, "consisting essentially of" cannot have this restrictive meaning in the present case. The board concludes that under the specific circumstances of the present case "consisting essentially of" excludes further active agents useful in the treatment of NIDDM but allows the presence of additional compounds forming the carrier of tetrahydrolipstatin.

The passage on page 1, lines 23-27, of the original application discloses that tetrahydrolipstatin, when administered orally, is useful in the treatment and prevention of NIDDM. This disclosure does not specifically mention that tetrahydrolipstatin is used in the absence of further active agents. However, the passage on page 2, lines 22-23, indicates that the pharmaceutical preparations "can also contain still other therapeutically valuable substances" [emphasis by the board], which means that the absence of such therapeutically valuable substances is clearly envisaged. Furthermore, all three formulation examples (examples 1 to 3) concern compositions with tetrahydrolipstatin as the only active agent. The board concludes therefrom that treatment of NIDDM with oral compositions comprising tetrahydrolipstatin as the sole active agent constitutes the most preferred embodiment of the original application. As a consequence, the substitution of "consisting essentially of" for "comprising" is allowable under Article 123(2) EPC.

3.2 Addition of the feature "for treating type II diabetes mellitus per se"

This feature is not explicitly mentioned in the original application either. As a first step, it is necessary to construe the meaning of "for treating type II diabetes mellitus per se". The board agrees with the respondent that this expression defines a treatment which is independent of weight loss. As a next step, it has to be evaluated whether or not the original application contains an implicit disclosure thereof. In this context, it is noted that obesity is a well-known risk factor for NIDDM and that weight loss is not merely an unspecific preventive activity but constitutes a concrete form of treatment of NIDDM (see the first sentence and in particular the second sentence of the summary of document (11), which indicates that reduction of weight excess comes to the front line in the prevention and management of NIDDM [emphasis by the board]). This is confirmed in the original application on page 1, lines 7-8, which read: "The initial approach in treating obese patients affected with type II diabetes mellitus is weight reduction" [emphasis by the board]. As a consequence, treatment of NIDDM which is independent of weight loss, and treatment of NIDDM by weight loss, represent two subcategories of the treatment of NIDDM in general.

The respondent argued that page 1 of the original application contained a specific disclosure of the use of tetrahydrolipstatin for the treatment of type II diabetes mellitus per se. In particular, reference was made to the fact that the passage in lines 18-21, which concerns a prior-art citation (US-A-4 598 089), according to which tetrahydrolipstatin is a known compound useful for the control or prevention of obesity and hyperlipidemia, was immediately followed by the statement "[i]t has now surprisingly been found that a gastrointestinal lipase inhibitor, preferably tetrahydrolipstatin, when administered orally, is useful in the treatment and prevention of type II diabetes mellitus", which, according to the respondent, could in this context only mean treatment and prevention of type II diabetes mellitus per se, i.e. independent of weight loss.

The board cannot follow this reasoning: the passage on page 1, lines 18-27 says that in the prior art, tetrahydrolipstatin was used for the treatment of obesity and hyperlipidemia. In contrast, the present invention concerns the use of tetrahydrolipstatin for the treatment of type II diabetes mellitus, i.e. type II diabetes mellitus in general. There is, however, no reference in this passage as to whether said treatment is associated with or independent of weight loss. In other words, the subcategory "treatment of type II diabetes mellitus independent of weight loss" is not specifically disclosed therein.

This conclusion is not changed by the fact that the use of tetrahydrolipstatin for treating type II diabetes mellitus treatment is characterised as "surprising" (see page 1, line 23). It might be argued that including this judgmental term constitutes a pointer towards treatment of type II diabetes mellitus independent of weight loss, as treatment in combination with weight reduction would not be surprising in view of the statements further up on page 1 that (a) the initial approach in treating obese patients affected with type II diabetes mellitus is weight reduction (page 1, lines 7-8) and (b) tetrahydrolipstatin is known to be useful for the control or prevention of obesity and hyperlipidemia (page 1, lines 18-21). However, the disclosure of an amendment in the original application, no matter whether it is explicit or implicit, must be unambiguous and can therefore not be based on an evaluation of what the author of the original application might or might not consider as surprising. Moreover, the skilled person will read the original application in its entirety and learn from example 4 that weight reduction is an important issue in the present invention. Example 4, which concerns a study of patients suffering from NIDDM, emphasises that 30% of patients treated with tetrahydrolipstatin achieved at least a 5% reduction in baseline body weight.

The board therefore comes to the conclusion that the original application does not specifically disclose, neither by explicit nor by implicit disclosure, the use of tetrahydrolipstatin for the manufacture of an oral pharmaceutical preparation for treating type II diabetes mellitus per se, i.e. independent of weight reduction. The requirements of Article 123(2) EPC are therefore not met.

4. Auxiliary request I - Article 123(3) EPC

Deletion of "per se" from claim 1 of auxiliary request I means that, in contrast to the claims as granted, treatment by tetrahydrolipstatin is no longer restricted to type II diabetes mellitus independent of weight reduction, but encompasses treatment of any type of type II diabetes mellitus. In other words, the scope of protection has been extended from the treatment of a specific subcategory of NIDDM to NIDDM in general. As a consequence, the requirements of Article 123(3) EPC are not met.

5. Auxiliary request II - Article 123(2) EPC

Compared to the main request, the subject-matter of claim 1 of auxiliary request II has been narrowed down to the use of tetrahydrolipstatin for the manufacture of an oral hypoglycemic pharmaceutical preparation for treating type II diabetes mellitus. Such a use is not mentioned in the original application. The passage on page 1, lines 7-9, indicates that the initial treatment of obese patients affected with NIDDM is weight reduction and that other types of treatment include oral hypoglycemics and insulin. However, the combination of this passage, which concerns the prior art, with the statement in lines 23-25 of the same page that it has now surprisingly been found that tetrahydrolipstatin, when administered orally, is useful in the treatment and prevention of type II diabetes mellitus, does not provide a basis for its use for the manufacture of an oral hypoglycemic pharmaceutical preparation as claimed in claim 1 of auxiliary request II. As was already mentioned above (see third paragraph of point 3.2), the original application discloses the use of tetrahydro-lipstatin for the treatment of NIDDM in general. There is, however, no basis for the specific subcategory (dependent or independent, hypoglycemic, etc.). As a consequence, the requirements of Article 123(2) EPC are not met.

6. Auxiliary request III - Article 123(2) EPC

6.1 Compared to the main request, the subject-matter of claim 1 of auxiliary request III additionally comprises a disclaimer disclaiming obese subjects, thus restricting the treatment of NIDDM to non-obese subjects. According to decision G 2/10 of 30 August 2011, an amendment to a claim by the introduction of a disclaimer disclaiming from it subject-matter disclosed in the application as filed infringes Article 123(2) EPC if the subject-matter remaining in the claim after the introduction of the disclaimer is not, be it explicitly or implicitly, directly and unambiguously disclosed to the skilled person, using common general knowledge, in the application as filed (see point 1a of the order).

The original application discloses on page 1, lines 7-9 that the initial approach in treating obese patients affected with type II diabetes mellitus is weight reduction. Later on (see page 1, lines 18-21), tetrahydrolipstatin is mentioned as a known compound useful for the control or prevention of obesity and hyperlipidemia. However, as pointed out in point 5 above in connection with claim 1 of auxiliary request II, the combination of these passages concerning the prior art with the statement in lines 23-25 of the same page that it has now surprisingly been found that tetrahydrolipstatin, when administered orally, is useful in the treatment and prevention of type II diabetes mellitus, does not provide a basis for its use for the manufacture of an oral hypoglycemic pharmaceutical preparation for specific administration to non-obese patients. As mentioned above (see third paragraph of point 3.2), the original application discloses the use of tetrahydrolipstatin for the treatment of NIDDM in general. There is, however, no direct and unambiguous basis, be it by explicit or implicit disclosure, for specific subcategories such as the treatment of NIDDM in non-obese subjects. As a consequence, the requirements of Article 123(2) EPC are not met.

7. Reimbursement of the appeal fee

According to Article 113(1) EPC, the decisions of the European Patent Office may only be based on grounds or evidence on which the parties concerned have had an opportunity to present their comments. Established jurisprudence has interpreted this provision to mean that the comments presented must be considered in the ensuing decision. Thus, a decision which fails to take explicitly into account potentially refutative arguments submitted by a party contravenes Article 113(1) EPC, thereby constituting a substantial procedural violation (see decision T 0246/08 of 14 August 2008, point 2.2 of the reasons for the decision). In the present case, the contested patent was opposed inter alia under Article 100(b) EPC for insufficiency of disclosure. This ground of opposition was discussed at the oral proceedings. However, the decision under appeal, in which the patent and the invention to which it relates were found to meet the requirements of the EPC, does not contain any reasoning at all in connection with insufficiency of disclosure. Therefore, a substantial procedural violation has occurred.

The minutes of the oral proceedings reveal (see first paragraph on page 2) that the chairman of the opposition division announced after deliberation that the requirements of Article 83 EPC were met and that Article 100(b) EPC did not prejudice the maintenance of the patent, which means that the failure to consider sufficiency of disclosure had no influence on the final decision to maintain the patent in amended form. As a consequence, the board concludes that reimbursement of the appeal fee is not equitable, as the substantial procedural violation was not sufficiently closely linked to the need to pay the appeal fee.