Albireo Pharma Inc. closed its underwritten public offering of 2.2 million common shares at $20.50 per share.

In addition, the underwriters exercised an option to buy an additional 330,000 shares.

Gross proceeds from the offering amounted to about $51.9 million, with net proceeds of about $48.2 million.

Cowen and William Blair acted as joint book-running managers and representatives of the underwriters, with Needham & Co. and Wedbush PacGrow as co-managers in the offering.