For Further Information Contact: Patrick J. McEnany Melody Carey Catalyst Pharmaceutical Partners Rx Communications Group Chief Executive Officer Co-President (305) 529-2522 (917) 322-2

Catalyst Pharmaceutical Partners Prices Registered Direct Public Offering

CORAL GABLES, FL, September 5, 2013 Catalyst Pharmaceutical Partners, Inc. (NASDAQ: CPRX) announced today that it has entered into

definitive agreements to sell 8.8 million shares of its common stock in a registered direct public offering. The offering price for each share of common stock is $1.72, resulting in gross proceeds of approximately $15.1 million.

The closing of this offering is expected to take place on or about September 10, 2013, subject to satisfaction of customary closing conditions. Catalyst

expects to use the net proceeds from this offering to fund costs associated with the Company s product development efforts for Firdapse , and for general corporate purposes. Roth Capital Partners has acted as the exclusive placement agent

for the transaction. Further, Aegis Capital Corp., Maxim Group LLC and H.C. Wainwright & Co. have acted as financial advisers with respect to this offering.

The shares are being offered pursuant to a shelf registration statement on Form S-3 (File No. 333-170945) filed pursuant to the Securities Act of 1933,

as amended, which was previously filed with, and declared effective by, the Securities and Exchange Commission (SEC). A prospectus supplement relating to the offering will be filed with the SEC and will be available on the SEC s website at

This press release does not and shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there

be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. Copies of the prospectus

supplement and the accompanying base prospectus may be obtained, when available, from Roth Capital Partners, LLC, 888 San Clemente Drive, Newport Beach, CA 92660, (800) 678-9147 or by accessing the SEC s website, http://www.sec.gov.

About Catalyst Pharmaceutical Partners

Catalyst Pharmaceutical Partners, Inc. is a specialty pharmaceutical company focused on the development and commercialization of novel prescription drugs

targeting rare (orphan) neuromuscular and neurological diseases, including Lambert-Eaton Myasthenic Syndrome (LEMS), infantile spasms, and Tourette Syndrome. Catalyst s lead candidate, Firdapse for the treatment of LEMS, is currently

undergoing testing in a global, multi-center, pivotal phase III trial. Catalyst is also developing a potentially safer and more potent vigabatrin analog (designated CPP-115) to treat infantile spasms, and epilepsy, as well as other neurological

conditions associated with reduced GABAergic signaling, like post-traumatic stress disorder and Tourette Syndrome.

Forward-Looking Statements

This press release contains forward-looking statements. Forward-looking statements involve known and unknown risks and uncertainties, which may cause

Catalyst s actual results in future periods to differ materially from forecasted results. A number of factors, including the timing of completion of Catalyst s currently ongoing Phase III trial of Firdapse , whether the Phase III

trial will be successful, whether the receipt of breakthrough therapy designation for Firdapse will expedite the development and review of Firdapse by the FDA or the likelihood that the product will be found to be safe and effective,

whether an NDA for Firdapse will ever be accepted for filing by the FDA, the timing of any such NDA filing or acceptance, whether any of Catalyst s product candidates will ever be approved for commercialization or successfully

commercialized, and those other factors described in Catalyst s Annual Report on Form 10-K for the fiscal year 2012 and other filings with the U.S. Securities and Exchange Commission (SEC), could adversely affect Catalyst. Copies of

Catalyst s filings with the SEC are available from the SEC, may be found on Catalyst s website or may be obtained upon request from Catalyst. Catalyst does not undertake any obligation to update the information contained herein, which

speaks only as of this date.