SAN DIEGO, Calif., May 23, 2005 /PRNewswire-FirstCall via COMTEX/ -- CoTherix, Inc. (Nasdaq: CTRX) announced today that researchers have presented results involving inhaled iloprost therapy for the treatment of pulmonary arterial hypertension (PAH), a debilitating and potentially fatal disease characterized by high blood pressure in the pulmonary arteries. Results were presented at the American Thoracic Society (ATS) International Conference in San Diego during the Thematic Poster Session for Pulmonary Hypertension.

Ventavis(R) (iloprost) Inhalation Solution was approved by the U.S. Food and Drug Administration (FDA) on December 29, 2004 for the treatment of PAH (World Health Organization Group I) in patients with NYHA Class III or IV symptoms.

"These data demonstrated the long-term safety and efficacy of inhaled iloprost in NYHA Class III and IV patients. In addition, the efficacy of inhaled iloprost after an overnight break supports the value of intermittent dosing," said Horst Olschewski, M.D., Professor and Chair, Division of Pulmonology, Medical University, Graz, Austria. "For physicians considering prostacylin therapy for their PAH patients, inhaled iloprost provides them with a non-invasive treatment option."

Inhaled Iloprost Effective for Long-Term Treatment of PH

H. Olschewski et al. (A57; Poster K29) presented data from a follow-up study investigating the long-term (LT) safety, dosing and clinical benefit of therapy with inhaled iloprost over a two-year period. 52 pulmonary hypertension (PH) patients who completed an initial 12-week randomized controlled study were given open-label inhaled iloprost treatment for two years. The study demonstrated that inhaled iloprost was effective for the long-term treatment of PH in those patients, with two-year data suggesting sustained clinical benefit. In addition, no significant dose increase was required to maintain clinical benefit. Heart failure due to PH was the most common serious adverse event.

Among 4/30 (13%) of iloprost-treated patients who met composite clinical response criteria (>10% increase in 6 minute walk test (MWT) + improvement in NYHA class + no deterioration/death) at 12 weeks, all maintained their response after 2 years. No patients in the control group met the response criteria at 12 weeks; however, five met the criteria upon long-term treatment with inhaled iloprost. Patients with primary or idiopathic pulmonary hypertension (n=39) had a two-year survival rate of 91% (95% CI: 75.8%-97.6%) compared with a predicted survival of 63% for an untreated historical cohort (based upon the NIH registry).

"Intermittent therapy with inhaled iloprost improved exercise capacity and pulmonary hemodynamics while reducing the risk of developing tolerance and rebound. It also avoids the inconvenience and complications that are associated with chronic indwelling catheters. This study shows that inhaled iloprost can safely and effectively be administered long-term, with maintenance of efficacy," said Dr. Olschewski.

Study Supports Use of Inhaled Iloprost in Patients with NYHA Class IV Pulmonary Hypertension

H. Olschewski et al. (A57; Poster K28) also presented subgroup analyses from a 12-week randomized controlled study which included 83 patients with NYHA Class IV PH (chronic thrombotic and/or embolic disease). The study was designed to compare the efficacy of treatment with inhaled iloprost to placebo.

Researchers reported that patients in the study treated with inhaled iloprost showed a statistically significant improvement in clinically relevant measures of efficacy. The primary clinical endpoint for the trial was a composite of: (1) an improvement in NYHA functional class, (2) an increase in the distance walked in six minutes of at least 10%, and (3) no clinical deterioration. For these Class IV patients, the difference between the two groups was statistically significant (P=0.022) with patients in the inhaled iloprost group performing significantly better than those in the placebo group. The response rate for the primary efficacy endpoint among PH patients was 17 percent for patients treated with inhaled iloprost compared with two percent for the placebo treated patients (p=0.022).

Clinical Benefit of Inhaled Iloprost Maintained during Period between Dosages

L.J. Rubin et al. (A57; Poster K61) presented data from a placebo-controlled study of 203 PH patients investigating the effects of intermittent dosing of inhaled iloprost. The study showed that inhaled iloprost had a sustained treatment benefit in PH patients when assessed at the point of lowest concentration during the dosage cycle. Inhaled iloprost is given regularly during the day via direct pulmonary delivery, but patients do not administer the therapy while they sleep.

In iloprost-treated patients, the absolute change in six-minute walk distance (6-MWD) following 12 weeks of therapy when measured after periods of two to 12 hours since the last inhalation was +11 +/- 69 m (mean +/- SD), compared to a decrease of -11 +/- 82 m in the placebo group. This represents a placebo-corrected improvement of 22 meters (p=0.052). Hemodynamic parameters evaluated before inhalation (trough drug effect) improved or remained stable for the iloprost group versus significant deterioration in the placebo group when compared with baseline (10% increase in PVR, a 5% decrease in CO, and a 5% decrease in SVO2 over 12 weeks in the placebo group).

About PAH

PAH affects an estimated 50,000 patients in the United States, with only about 15,000 diagnosed and under treatment. Its cause may be unknown, or result from other diseases that cause a restriction of blood flow to the lungs, including scleroderma, HIV and lupus. Symptoms of the disease include fatigue, shortness of breath on exertion, chest pain and dizziness. Left untreated, the median survival time following diagnosis may be as short as three years.

About Ventavis

Ventavis(R) (iloprost) Inhalation Solution was approved by the U.S. Food and Drug Administration (FDA) on December 29, 2004 for the treatment of PAH (WHO Group I) in patients with NYHA Class III or IV symptoms. Ventavis is the newest entry into the prostacyclin class of PAH treatments. Prior to the introduction of Ventavis, prostacyclin therapies for PAH required continuous delivery through subcutaneous or intravenous routes -- invasive treatments which are difficult to tolerate and/or require complicated maintenance. Ventavis provides PAH patients with a non-invasive, inhaled treatment option. Ventavis is not approved for the treatment of pulmonary hypertension due to chronic thrombotic and/or embolic disease.

In clinical studies of Ventavis monotherapy in treating PAH, 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 included congestive heart failure, chest pain, supraventricular tachycardia, dyspnea, peripheral edema, and kidney failure.

For important additional information concerning the safety and use of Ventavis, please see the prescribing information available at www.4Ventavis.com.

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 is marketed in the United States for the treatment of pulmonary arterial hypertension (WHO Group I), 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. Ventavis was approved by the FDA in December 2004. CoTherix and the CoTherix logo are trademarks of CoTherix, Inc. Ventavis is a trademark of Schering AG, Germany. More information can be found at www.cotherix.com.

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, goals, intentions, initiatives or strategies. The results of initial clinical trials do not necessarily predict the results of later stage clinical trials. Data collected from clinical trials are subject to varying interpretation, and may be deemed insufficient by the FDA or other regulatory bodies reviewing applications for market approval or label expansion of any product or product candidate. We cannot guarantee that any product candidate will receive FDA or other regulatory approval or that we will seek any such approval. 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. Our actual results and other event could differ materially from our current expectations. Factors that could cause or contribute to such differences include, but are not limited to, factors discussed in the "Risk Factors and Other Uncertainties" section of our Annual Report on Form 10-Q filed on May 16, 2005.

SOURCE CoTherix, Inc.

investors, Anne Bowdidge, Senior Director of Investor Relations for CoTherix, Inc., +1-650-808-6551; or media, Kathleen Harrison of Fleishman Hillard, +1-415-318-4154, for CoTherix, Inc.