The topic of pharmaceutical, biological and chemical patents is a special matter within European and German patent law. There are several structural alterations, like polymorphism and enantiomerism, leading to a derivative of a substance that is comprised in the prior art. This gives rise to the question under what circumstances such alterations can be novel and in which cases they are included in the state of the art. But even if a substance is prior art, a new medical use of it can be patented, as such medical use patents are politically intended to promote medical research.

On the...