Dendreon said Thursday it has raised $356 million in net proceeds from selling 15 million shares of stock at $24.75 apiece. The Seattle biotechnology company could tack on another $50 million more if its investment bankers exercise an option for an additional 2.25 million shares.

Dendreon said Thursday it has raised $356 million in net proceeds from selling 15 million shares of stock at $24.75 apiece, and could tack on another $50 million if its investment bankers exercise an option for an additional 2.25 million shares.

The Seattle-based biotechnology company, which is awaiting a Food and Drug Administration decision early next year on its prostate cancer therapy, said it will use the money to expand its manufacturing facilities, information technology and other operations.