T 1487/19 17-11-2021

I. European patent No. 2 307 011 (patent in suit) was granted with a sole claim, which reads as follows:

"1. Mazindol, or a pharmaceutically acceptable salt thereof, for use in the treatment of inattention, hyperactivity and impulsivity caused by attention deficient hyperactivity disorder (ADHD) in a mammalian patient, wherein the mazindol, or the pharmaceutically acceptable salt thereof is the only active agent, and wherein mazindol is administered as a daily dose of 2.5 mg."

II. The patent was opposed under Article 100(a) and (c) EPC on the grounds that the claimed subject-matter lacked novelty and inventive step and extended beyond the content of the application as filed.

III. The patent proprietor requested as its main request that the opposition be rejected, and also filed three amended versions of claim 1 as its first to third auxiliary claim requests.

The sole claim of the first auxiliary request is identical to claim 1 as granted (main request), except that it specifies that the patient is a human child.

The sole claim of the second auxiliary request is identical to claim 1 as granted, except that it further specifies that the patient is a human between 11 and 14 years of age.

The sole claim of the third auxiliary request is identical to claim 1 as granted, except that it further specifies that the patient is a male human between 11 and 14 years of age.

IV. In the discussion concerning the issue of added subject-matter (Articles 100(c) and 123(2) EPC), the patent proprietor relied, inter alia, on Example 3 in paragraph [0123] of the application as filed as the basis for the dosage regimen of 2.5 mg daily, recited in the claims of all the requests. Example 3 reads as follows:

"Example 3: P. M. is a 14 year old male. At 4 years of age a diagnosis of ADHD was made and he was treated with Ritalin (methylphenidate) with some improvement in attention span but little effect on several other neurobehavioral symptoms, including abusive behavior and depression. At age 9 years of age, he was also being treated with risperidone which continued for 2 years. At 13 years of age the patient was started on Mazindol at 2.5 mg BID and the Ritalin was discontinued. Within 2 months he reported improved attention span, loss of hyperactivity and his bad behavior as a result of his impulsivity significantly improved. Subsequently, the risperidone was then completely discontinued without any recurrence of symptoms of ADHD (i.e. poor attention span, hyperactivity, or inappropriate behavior). The patient was then maintained on Mazindol at 2.5 mg/day as the sole agent without the return of any symptoms of ADHD over the next 3 years."

V. The decision under appeal is the opposition division's decision revoking the patent, announced on 17 January 2019 and posted on 15 February 2019.

VI. According to the decision under appeal, the subject-matter of claim 1 as granted (main request) was a generalisation from Example 3 of the application as filed. As the example concerned an individual patient with a specific treatment history, this generalisation was not allowable as it extended beyond the content of the application as filed. Analogous objections applied to the subject-matter of claim 1 of each of the first to third auxiliary requests (Articles 100(c) and 123(2) EPC).

VII. The patent proprietor (appellant) filed an appeal against this decision.

VIII. With the statement setting out the grounds of appeal, the appellant re-submitted the claims according to the main request and first to third auxiliary requests considered in the decision under appeal.

Hence, the sole claim of the main request is identical to claim 1 as granted (see points III. and I. above), and the claims of the auxiliary requests are as set out in point III. above.

IX. By letter of 20 October 2021, the appellant advised that it would not be attending the oral proceedings scheduled for 17 November 2021 and requested that a decision be issued in its absence. As a consequence, the board cancelled the oral proceedings and the appeal proceedings continued in writing.

X. The appellant's arguments may be summarised as follows:

The feature in claim 1 as granted that required mazindol to be administered as a daily dose of 2.5 mg was based on paragraphs [0050] and [0052] or on Example 3 of the application as filed, or on all of these passages taken in combination.

The subject-matter as claimed in the main request met the criteria for a permissible intermediate generalisation on the basis of Example 3.

In particular:

- the claim feature "for use in the treatment of inattention, hyperactivity and impulsivity caused by attention deficit hyperactivity disorder (ADHD) in a mammalian patient" meant that the patient to be treated must suffer from all three symptoms;

- the patient in Example 3 had suffered from all three symptoms, which had been successfully treated with 2.5 mg/day mazindol as the sole agent;

- the patient's previous treatment history with other medication was irrelevant. This was because:

- the symptoms of ADHD could not be cured but had to be treated by regularly administering a suitable medicament,

- any previously administered medication (methylphenidate, risperidone) would have been eliminated from the patient's body within a matter of days after discontinuation and would not have affected the subsequent treatment.

This reasoning also applied to the claims of all the auxiliary requests. Moreover, the definitions of the patient in the auxiliary requests took further clinical circumstances of the patient in Example 3 into account.

The definition of the patient as "a human child" in the first auxiliary request was based on paragraphs [0022] and [0027] of the application as filed and on the fact that the patient in Example 3 was a child.

The definitions of the patient in the second and third auxiliary requests, too, were based on Example 3. In this context, the person skilled in the art would understand that Example 3 contained an obvious error in the sentence "At 13 years of age the patient was started on Mazindol at 2.5 mg BID", which should instead read: "At 11 years of age (...)".

XI. The opponent's (respondent's) arguments may be summarised as follows:

Paragraphs [0050] and [0052] of the application as filed did not disclose a daily dose of 2.5 mg mazindol.

Example 3 of the application as filed concerned an individual case with a specific treatment history involving other medicaments. On that basis, the dosage regimen of 2.5 mg mazindol daily could not be interpreted as an effective ADHD treatment by itself, let alone for patients of any age. It was not apparent from Example 3 that monotherapy with 2.5 mg mazindol alone treated the ADHD symptoms, or that the absence of returned symptoms was unrelated to the age of the patient and his progression into adulthood, which in some patients could have a beneficial effect.

The same reasoning applied to the auxiliary requests. Furthermore:

- the patient in Example 3 was not a child (as defined in claim 1 of the first auxiliary request);

- contrary to the appellant's assertion, it was not apparent from the text of Example 3 that the patient's treatment with mazindol must have started at 11 years of age. Even if it were obvious to a reader that an error had occurred (which was, however, disputed), it was far from obvious how such an error should be corrected.

XII. The appellant requested that the decision under appeal be set aside and that the opposition be rejected (main request), or, in the alternative, that the patent be maintained in amended form on the basis of the claims of one of the first to third auxiliary requests, all filed with the statement setting out the grounds of appeal.

XIII. The respondent requested that the appeal be dismissed.