Bothell-based Alder BioPharmaceuticals, Inc. a clinical-stage biopharmaceutical company, announced on Jan. 22 that the underwriters of its previously announced public offering of common stock have exercised in full their option to purchase an additional 900,000 shares of common stock.

Gross proceeds from the offering of an aggregate of 6,900,000 shares at a public offering price of $29.50 per share, before underwriting discounts and commissions and offering expenses, were approximately $203.6 million.

Credit Suisse, Leerink Partners and Wells Fargo Securities acted as joint book-running managers for the offering. Sanford C. Bernstein acted as co-manager for the offering.

The Securities and Exchange Commission declared effective a registration statement relating to the offering of these securities on Jan. 8.