Eiger BioPharmaceuticals Announces Proposed Public Offering of Common Stock

PALO ALTO, Calif., Oct. 26, 2017

Eiger intends to use the net proceeds of the offering to fund the clinical development of its portfolio of four product candidates, and for working capital and other general corporate purposes.

A shelf registration statement relating to the shares of common stock offered in the public offering described above was filed with the Securities and Exchange Commission (SEC) on June 17, 2016 and declared effective by the SEC on August 4, 2016.  The offering will be made only by means of a written prospectus and prospectus supplement that form a part of the registration statement.  A preliminary prospectus supplement and accompanying prospectus relating to the offering will be filed with the SEC and will be available on the SEC's website at www.sec.gov.  Copies of the preliminary prospectus supplement and the accompanying prospectus, when available, may also be obtained by contacting BTIG, LLC, 825 Third Avenue, 6th Floor, New York, NY 10022, or by email at equitycapitalmarkets@btig.com, or by phone at 212-593-7555.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy the securities being offered, nor shall there be any sale of the securities being offered in any state or other jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such state or other jurisdiction.

About Eiger BioPharmaceuticals, Inc.
Eiger is a clinical-stage biopharmaceutical company committed to bringing to market novel products for the treatment of rare diseases. The company has built a diverse portfolio of well-characterized product candidates with the potential to address diseases for which the unmet medical need is high, the biology for treatment is clear, and for which an effective therapy is urgently needed.

Forward-Looking Statements 
This press release contains forward-looking statements that involve substantial risks and uncertainties.  All statements, other than statements of historical facts, included in this press release regarding the anticipated public offering, anticipated use of proceeds, beliefs and expectations of management are forward-looking statements.  These forward-looking statements may be accompanied by such words as "anticipate," "believe," "could," "estimate," "expect," "forecast," "intend," "may," "plan," "potential," "project," "target," "will" and other words and terms of similar meaning.  Various important factors could cause actual results or events to differ materially from the forward-looking statements that Eiger makes, including uncertainties related to market conditions and the completion of the public offering on the anticipated terms or at all, and the risks described in the "Risk Factors" sections in the Quarterly Report on Form 10-Q for the period ended June 30, 2017 and Eiger's periodic reports filed with the SEC.  Eiger does not assume any obligation to update any forward-looking statements, except as required by law.