Researchers are increasingly focusing on the tau protein as a crucial target in the fight against Alzheimer's disease, suggesting that therapies aimed at reducing tau accumulation could offer significant benefits. While amyloid plaques have long been the primary focus of Alzheimer's research and treatment, emerging studies indicate that tau tangles may play a more direct role in disease progression.
Scientists like Mucke propose that under normal conditions, tau protein is vital for maintaining the structure of neurons. However, when disease processes associated with Alzheimer's, and potentially other neurological conditions such as epilepsy and autism spectrum disorders, begin to manifest, tau can become an enabler of harmful mechanisms. "If a disease comes along—not only Alzheimer's, but epilepsy and autism spectrum disorders—tau reduction can dampen the down processes that lead to these diseases," Mucke stated. He advocates for continued debate on tau's precise functions but emphasizes that reducing its levels is a critical therapeutic goal, irrespective of its exact role in Alzheimer's pathology.
Experimental drugs targeting tau are showing promise. One such drug, diranersen, is currently in early-stage trials. If further studies confirm its efficacy, as Biogen plans to conduct, it could pave the way for combination therapies. VandeVrede, envisioning a future treatment landscape, suggested that diranersen might eventually be used alongside anti-amyloid drugs. Current anti-amyloid medications can, at best, slow cognitive decline by approximately 30%. "If we see the benefit of tau, then my instinct is that clinicians will think, 'What if we use both?'" VandeVrede commented. "If you slow down something with a drug, and can then slow it down again with another drug, you end up with something that may look like stabilization. And that would be a huge win in the Alzheimer’s world."