- The present medical use claim (post-EPC2000) at the EPO has the following basic format:
‘Substance X for use in a method of treating condition Y’
Medical use claims can additionally be limited in many different ways including:
– administration schedule
– coadministration with another substance
– patient group
In theory medical use claims can be limited in any way that a method of treatment claim (using a substance) could be limited. In practice though there are limits to what the EPO will accept.
2. Can substance X be defined as any therapeutic substance and/or Y as any condition? That might for example be required when the invention relates to a new delivery method that can be applied to any substance and condition. Examiners are cautious about allowing substances or disease conditions to be defined functionally in claims, and so this can turn into a difficult issue, but not an unwinnable one.
3. Does X have to be a chemical substance? At the moment it does seem that way. So X cannot be an electrical impulse, electromagnetic radiation or a device. However there does seem to be some hope that the present EPC2000 medical use claim could allow X to be a device.
4. Can a patient group which overlaps with a prior art patient group confer novelty? According to previous case law yes, but it seems that this could change (see this).
5. Can a medical claim use refer to other physical steps, such as selecting a patient, screening for the therapeutic substance or a method of making the substance? It is difficult to be certain about this issue. It requires the case law to develop further.
6. Remember that the exclusion concerning surgical methods is interpreted broadly at the EPO, and so it can be possible to fall foul of when referring to injecting or carrying our other physical treatments of the body.
7. A medical use claim cannot be rendered novel by reference to the (previously unknown) mechanism of action of a known therapy. In order to confer novelty, knowledge of the mechanism must be correlated with action(s) that would be done differently compared to the prior art, such as the timing of therapy or the patient group, and the claim must be limited by features that reflect the difference(s).