Amgen Inc. is a new investor in San Francisco’s Alector, a biotech focused on developing immuno-modulatory therapies for Alzheimer’s disease and other neurodegenerative disorders.

The startup announced Friday that it has received $29.5 million in Series D funding, which was led by Dementia Discovery Fund. Other investors include pharmaceutical company AbbVie in Chicago and equity firm Topspin Partners in Mamaroneck, N.Y., in addition to Amgen in Thousand Oaks.

Earlier this year, Alector completed a Series C financing of $32 million, bringing their total amount of capital raised in 2015 to $62 million.

The company said the money will be used to advance its drug candidates and expand its discovery pipeline.

“The combination of strategic pharmaceutical investors, blue-chip venture capital firms and innovation-specific investors is a clear indication of the broad potential for Alector’s immuno-modulatory approach to treat neurologic diseases,” Arnon Rosenthal, co-founder and chief executive of Alector, said in a statement.

Amgen shares closed down $2.27 or 1.5 percent to $150.71 on the Nasdaq.