Is tau the way forward to treat Alzheimer’s disease?


Merck & Co. (Merck) has reported that it entered a global license agreement with Teijin Pharma for the development and commercialisation of a preclinical anti-tau antibody as a potential treatment for Alzheimer’s disease.

Merck will take on all development responsibilities for the drug and provide an upfront payment, as well as regulatory and sales milestone payments, to Teijin Pharma. The acquisition of an anti-tau antibody to Merck’s pipeline represents a growing trend for pharmaceutical companies to target the tau protein as a way forward to treat Alzheimer’s disease.

Much of the research and clinical testing to date has focused on targeting the amyloid protein pathway. However, with the failure of all clinical trials directed to this mechanism of action to date, companies have begun to search for alternative approaches. The tau protein represents a promising target for the treatment of Alzheimer’s, as it is one of the disease's major hallmarks. It also demonstrates a close role in neuronal degeneration and to clinical symptoms. Many key pharmaceutical players are now investing in their pipeline to evaluate this target further.

By acquiring an anti-tau antibody, Merck now joins Eli Lilly, Roche, AbbVie, Biogen, and Lundbeck in the race to develop this therapy. AbbVie and Biogen are currently the furthest along with clinical development, with AbbVie initiating Phase II trials in Q4 2016, while Biogen recently acquired the Phase II-ready anti-tau candidate BMS-986168 from BMS in April 2017.

The clinical development strategy may also be critical to the success of these antibodies, with both AbbVie and Biogen investigating their anti-tau antibody therapies in Alzheimer’s disease and progressive supranuclear palsy (PSP) patients.

As discussed in GlobalData’s recent Tauopathies PharmaFocus report, patients with PSP represent a more homogeneous group of patients for clinical testing, with the disorder only caused by the dysfunction of tau protein. As such, this patient population may provide a clearer and more efficient opportunity for companies to evaluate efficacy of their drug candidates, prior to evaluation in the much larger and more heterogeneous population of patients with Alzheimer’s disease.

While the efficacy of these antibodies is yet to have been demonstrated in any patient population, all companies working in this market clearly see the opportunities that anti-tau antibodies may provide. The first drug to market will likely command a large patient share and high price, and the reward of developing an approved therapy for Alzheimer’s patients is expected to be lucrative.