An infringement case over transgenic models of Alzheimer's disease has finally been settled between Elan, a neuroscience-based biotechnology company, and the non-profit Mayo Foundation for Medical Education and Research. Elan and the Mayo Foundation have now entered into a cross-license agreement that facilitates the use by both parties of these transgenic models among other research tools used to study Alzheimer's disease, and allows Mayo to collaborate with third parties on research involving these tools.

The dispute, which has been followed closely by the neuroscience community, began in the late 1990s when Elan sued the Mayo Foundation for allegedly infringing the two patents it holds on its transgenic mouse models of Alzheimer's disease. The mice express a human gene that contains a mutation known as the 'Swedish mutation' of the amyloid precursor protein, the accumulation of which is well established as a contributory factor to Alzheimer's disease.

In response to Elan's accusations of infringement, Mayo claimed it had licences from patent holders for both the mutation and the mice, and counterclaimed that Elan's patents were obtained fraudulently and were therefore not enforceable.

US neuroscientists — many of whom were subpoenaed during the case — must finally be breathing a sigh of relief after a long battle that has compounded the difficulties of working in a field in which animal models are crucial to research and already of limited availability. Both parties have stated that they remain committed to making progress against Alzheimer's disease and that they will make their patents available for licensing to other research groups and companies.