AbbVie and Voyager Therapeutics team up for Alzheimer’s gene therapy

AbbVie is teaming up with Cambridge, Mass.-based Voyager Therapeutics to develop gene therapies for Alzheimer’s disease. The deal includes a $69 million upfront payment to Voyager and more than $1 billion in potential milestone payments.

AbbVie will provide antibodies targeted against tau, one of the two main proteins implicated in Alzheimer’s. The firm already has an anti-tau antibody in a Phase II clinical trial. Voyager will test encoding different versions of the antibodies into the DNA of an adeno-associated virus (AAV), a delivery vehicle used in many gene therapy trials to shuttle DNA into cells.

Researchers hope to prevent tau from clumping together and forming the toxic neurofibrillary tangles inside brain cells that are characteristic of Alzheimer’s. Tau is one of the most common Alzheimer’s drug targets, along with amyloid-β, a protein that clumps into plaques that clog up the spaces between brain cells.

But no one has successfully developed a drug based on reducing the buildup of amyloid-β or tau. In fact, just this month Merck & Co. ended its trial of a small-molecule drug designed to inhibit the production of amyloid-β.

Antibodies that target tau or amyloid-β are in development at many companies, but they aren’t always able to reach the brain in large numbers, even though injections of the drugs are typically given repeatedly. In contrast, a one-time injection of Voyager’s gene therapy could potentially result in long-lasting production of anti-tau antibodies in the brain. That injection might require surgery to deliver the therapy to a specific region of the brain, as in Voyager’s Parkinson’s and Huntington’s disease programs, or it could be injected into the cerebrospinal fluid, as in Voyager’s amyotrophic lateral sclerosis program.

Voyager will run the Alzheimer’s program through Phase I clinical trials, at which point AbbVie has the option to license it. The anti-tau therapy could also treat other neurodegenerative diseases related to tau, such as progressive supranuclear palsy and frontotemporal dementia.

AbbVie is looking at ways to tackle Alzheimer’s beyond tau. In October, the firm invested $225 million in South San Francisco-based Alector, which is designing antibodies that modulate the activity of immune cells found in the brain called microglia.