The American Lung Association and Myogen Announce Pulmonary Arterial Hypertension Educational Partnership

New York and Denver, September 6, 2006 – The American Lung Association and Myogen, Inc. (Nasdaq: MYOG) today announced that they will collaborate on a new public awareness initiative to educate the public about pulmonary arterial hypertension (PAH), a progressive and life-threatening disease that affects an estimated 200,000 patients worldwide.

The multi-year educational partnership will be launched this fall and will include a variety of outreach activities, all designed to better inform the public about signs and symptoms as well as treatment options for PAH. There is no known cure for PAH, but early diagnosis and treatment can reduce symptoms, improve quality of life, slow the progression of the disease and extend patients’ lives.

"We are pleased to collaborate with Myogen on this important educational partnership,” said Dr. Norman H. Edelman, Chief Medical Officer for the American Lung Association. “Our combined expertise in this area and commitment to improving patients’ lives will hopefully allow us to increase awareness and knowledge of this serious disease. Ultimately, we hope this education collaboration will benefit patients.”

“The American Lung Association is the nation’s oldest voluntary health organization and their dedication to the prevention of lung disease and to the promotion of lung health is unmatched,” said J. William Freytag, President and Chief Executive Officer of Myogen. “By partnering with such a respected organization, we can expand the collective knowledge base about PAH and employ their nationwide network and resources to broaden awareness of this disease.”

PAH is a highly debilitating disease characterized by severe constriction of the blood vessels in the lungs leading to very high pulmonary arterial pressures. These high pressures make it difficult for the heart to pump blood through the lungs to be oxygenated. Patients with PAH suffer from extreme shortness of breath and severe limitations of physical exertion as the heart struggles to pump against these high pressures. Patients with advanced stages of PAH have a poor prognosis and highly compromised quality of life. If untreated, they have a mean life expectancy of two to five years from diagnosis. PAH can occur with no known underlying cause, or it can occur secondary to diseases such as connective tissue disease, congenital heart defects, cirrhosis of the liver and human immunodeficiency virus (HIV) infection.

Therapies currently used for the treatment of PAH include anticoagulants; diuretics; calcium channel blockers; digoxin; prostacyclins; phosphodiesterase inhibitors and endothelin receptor antagonists.

About the American Lung Association
Beginning our second century, the American Lung Association is the leading organization working to prevent lung disease and promote lung health. Lung disease death rates continue to increase while other leading causes of death have declined. The American Lung Association funds vital research on the causes of and treatments for lung disease. With the generous support of the public, the American Lung Association is “Improving life, one breath at a time.” For more information about the American Lung Association or to support the work it does, call 1-800-LUNG-USA (1-800-586-4872) or log on to
www.lungusa.org.

About Myogen
Myogen has two product candidates in late-stage clinical development: ambrisentan for the treatment of patients with pulmonary arterial hypertension (PAH) and darusentan for the treatment of patients with resistant hypertension. Myogen and GlaxoSmithKline have entered into a global PAH collaboration in which Myogen has marketing and distribution rights to GlaxoSmithKline’s Flolan(R) (epoprostenol sodium) for Injection in the United States and GlaxoSmithKline has licensed ambrisentan from Myogen for all territories outside of the United States, where Myogen retains exclusive rights. Myogen also conducts a target and drug discovery research program focused on the development of diseasemodifying drugs for the treatment of chronic heart failure and related cardiovascular disorders. Please visit Myogen’s website at www.myogen.com.

Contact Information

Ilana Tabak

Manager, Media Relations

American Lung Association

Contact via E-mail