CAMBRIDGE, Mass.--(BUSINESS WIRE)--Ra Pharmaceuticals, Inc. (Nasdaq: RARX)  today announced that it intends to offer and sell, subject to market and other conditions, $100 million of its common stock in an underwritten public offering. Ra Pharma expects to grant the underwriters a 30-day option to purchase up to $15 million of additional shares of its common stock. There can be no assurance as to whether or when the offering may be completed, or as to the actual size or terms of the offering. All of the shares in the proposed offering are to be sold by Ra Pharma.

Jefferies, BMO Capital Markets, Stifel and Guggenheim Securities are acting as joint book-running managers for the offering. Baird is acting as lead manager for the offering.

Ra Pharma intends to use the net proceeds from the offering, in addition to its existing cash resources, to fund pre-commercialization activities for zilucoplan, extended release (XR) formulation of zilucoplan (life-cycle extension program), clinical development of pipeline programs, and for working capital and other general corporate purposes.

About Ra Pharmaceuticals, Inc.

Ra Pharma is a clinical-stage biopharmaceutical company focused on leading the field of complement biology to bring innovative and accessible therapies to patients with rare diseases. The Company discovers and develops peptides and small molecules to target key components of the complement cascade.