The News

CoTherix Reports Positive Clinical Data From STEP Study

08/03/2005

SOUTH SAN FRANCISCO, Calif., March 8 - CoTherix, Inc. announced today top-line safety and efficacy results from the STEP clinical study.  The analysis of this study showed that the combination of Ventavis(R) (iloprost) Inhalation Solution added to Tracleer(R) (bosentan) therapy was well tolerated and provided clinical benefit in patients with pulmonary arterial hypertension (PAH). The STEP (acronym for:  iloprost inhalation solution Safety and pilot efficacy Trial in combination with bosentan for Evaluation in Pulmonaryarterial hypertension) trial was a double-blind, placebo-controlled trial, in which PAH patients treated with Tracleer, an oral endothelin receptor antagonist, were randomized to receive either Ventavis (inhaled iloprost) or inhaled placebo in combination with Tracleer for 12 weeks.  Fifteen U.S. clinical sites enrolled 65 patients into the intent-to-treat analysis population (32 Ventavis and 33 placebo).  Baseline characteristics were well balanced across the two arms.  Compliance with scheduled doses was over 90% in each arm, with the majority of patients taking six inhalations per day. Common adverse events that occurred more frequently in the Ventavis arm were those known to be associated with inhaled prostacyclin administration and included flushing, headache, cough and jaw pain.  Syncope occurred less frequently when compared to placebo (one Ventavis and two placebo), and no serious syncope adverse events were reported in either treatment group.  No clinically relevant increases in laboratory abnormalities, including liver function tests, were observed in the combination treatment arm.  Serious adverse events were infrequent (five Ventavis patients and seven placebo patients). No deaths occurred in either treatment arm. Clinical benefits of adding Ventavis to Tracleer were observed in a number of secondary endpoints.  Combination treated patients (Ventavis plus Tracleer) in the 6-minute walk test walked a mean difference of 26 meters farther than patients treated only with Tracleer (p=0.051).  Other important clinical endpoints, including change in NYHA functional class, reduction in mean pulmonary artery pressure and delay in clinical deterioration were statistically significant (p values range from 0.02 to <0.0001).
"Like many other areas of medicine, we believe that the field of PAH is moving toward combination therapy," said Lewis J. Rubin, M.D., Professor of Medicine and Director, Pulmonary Hypertension Program at the University of California, San Diego.  "This trial brings us one step closer in understanding how combination therapies may be used to effectively treat PAH."

About CoTherix, Inc.
CoTherix, Inc. is a biopharmaceutical company focused on licensing, developing and commercializing therapeutic products for the treatment of cardiopulmonary and other chronic diseases. CoTherix's Ventavis(R) (iloprost) Inhalation Solution was approved by the FDA in December 2004 for the treatment of pulmonary arterial hypertension, a highly debilitating and potentially fatal disease characterized by high blood pressure in the pulmonary arteries of the lungs, in patients with NYHA Class III or IV symptoms. Ventavis is an inhaled formulation of iloprost, a synthetic compound that is structurally similar to prostacyclins. CoTherix and the CoTherix logo are trademarks of CoTherix, Inc. Ventavis is a trademark of Schering AG, Germany.

Safety Information
In previous clinical studies of Ventavis monotherapy, common adverse reactions due to Ventavis included: vasodilation (flushing, 27%), cough (39%), headache (30%), flu syndrome (14%), nausea (13%), jaw pain (12%), hypotension (11%), insomnia (8%) and syncope (8%); other serious adverse events reported with the use of Ventavis included congestive heart failure, chest pain, supraventricular tachycardia, dyspnea, peripheral edema, and kidney failure. Because of the risk of syncope, vital signs should be monitored while initiating Ventavis. Dose adjustments or a change in therapy should be considered if exertional syncope occurs. Ventavis should not be initiated in patients with systolic blood pressure lower than 85 mm Hg. Stop Ventavis immediately if signs of pulmonary edema occur. Ventavis has not been evaluated in patients with chronic obstructive pulmonary disease (COPD), severe asthma, or with acute pulmonary infections.

Forward-Looking Statements
The statements contained in this press release that are not purely historical are forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended.  Forward-looking statements in this press release include statements regarding our expectations, beliefs, hopes, intentions or strategies, including statements regarding the potential safety and efficacy of combination therapy to treat PAH (such as the combined use of Ventavis and Tracleer).  All forward-looking statements included in this press release are based upon information available to us as of the date hereof, and we assume no obligation to update any such forward-looking statement as a result of new information, future events or otherwise.  The results of initial clinical trials do not necessarily predict the results of later-stage clinical trials. Product candidates in later stages of clinical trials may fail to show the desired safety and efficacy despite having progressed through initial clinical trials. ecan not guarantee that data collected from clinical trials of any product candidate will be sufficient to support FDA or other regulatory approval. We are at an early stage of development and have not generated, and may not generate, any revenues.  Factors that could cause or contribute to such differences include, but are not limited to, factors discussed in the "Risk Factors" section of our Registration Statement on Form S-1 filed on January 12, 2005 and the related prospectus filed pursuant to Rule 424(b)(4) on February 10, 2005.