Athersys Inc. closed its underwritten public offering of 22,772,300 common shares at $1.01 per share.

The offering included the underwriters' full exercise of their option to buy an additional 2,970,300 common shares.

Athersys generated gross proceeds of about $23 million, before deducting underwriting discounts, commissions and estimated offering expenses.

The company intends to use the net proceeds for working capital, general corporate purposes, funding for its phase 3 MultiStem administration for stroke treatment and enhanced recovery clinical study and other ongoing clinical programs.

William Blair & Co. LLC is acting as sole book-running manager and Needham & Co. LLC is acting as lead manager for the offering. Maxim Group LLC served as financial adviser to Athersys.