Aradigm Initiates Trial of Lung Rx's Inhaled Treprostinil.

Bridging Study Compares AERx Essence([R]) System to Nebulizer Used in Phase 3 TRIUMPH trial

HAYWARD, Calif. -- Aradigm Corporation (OTCBB: ARDM) (the "Company") today announced it initiated a bridging clinical trial of inhaled treprostinil utilizing its AERx Essence([R]) pulmonary delivery system. The trial in healthy volunteers is being conducted in the United Kingdom to evaluate aerosol delivery by assessing lung distribution, pharmacokinetics and safety of inhaled treprostinil delivered by the AERx Essence system versus delivery with the Nebu-Tec OPTINEB*-ir nebulizer. The latter device was used by Lung Rx, Inc. (Lung Rx), a wholly owned subsidiary of United Therapeutics Corporation, in the recently concluded TRIUMPH (TReprostinil Sodium Inhalation Used in the Management of Pulmonary Arterial Hypertension) study of inhaled treprostinil in patients with Pulmonary Arterial Hypertension (PAH).

The Company was granted authorization to proceed with the clinical trial by the UK Medicinal Health Care products Regulatory Agency (MHRA) as required under the European Union Clinical Trials Directive.

"We are delighted that we are making good progress with Aradigm towards providing PAH patients with ever more convenient ways to treat their condition using the palm-sized AERx Essence inhaler," said Martine Rothblatt, Ph.D., Chairman and CEO of Lung Rx and United Therapeutics Corporation.

"This clinical trial is an important milestone for our company," said Igor Gonda, Ph.D., President and CEO of Aradigm. "First and foremost, it is a key step in our collaboration with Lung Rx. Second, it is another opportunity to demonstrate the value of the AERx technology for the development of important new therapeutic products administered by inhalation."

About Aradigm

Aradigm is an emerging specialty pharmaceutical company focused on the development and commercialization of a portfolio of drugs delivered by inhalation for the treatment of severe respiratory diseases by pulmonologists. Current activities include partnered and self-initiated development programs addressing the treatment of cystic fibrosis, bronchiectasis, pulmonary hypertension, asthma and bronchitis, inhalation anthrax infections and smoking cessation. More information about Aradigm can be found at www.aradigm.com.

About Lung Rx

Lung Rx, Inc. is a biotechnology company focused on unmet medical needs in pulmonary medicine and pulmonary delivery of innovative therapeutic products.

Except for the historical information contained herein, this news release contains forward-looking statements that involve risk and uncertainties, including the potential for new products, the execution of the Company's new strategy, the timing and completion of studies and clinical trials, and the receipt of royalty and other payments as well as the other risks detailed from time to time in Aradigm Corporation's Securities and Exchange Commission (SEC) filings, including the Company's Annual Report on Form 10-K, and quarterly reports on Form 10-Q.

Aradigm, AERx and AERx Essence are registered trademarks and the Aradigm Logo is a trademark of Aradigm Corporation. *Other names and brands may be claimed as the property of others.