Release issued 13th July 2005

HAYWARD, Calif., June 29 - Aradigm Corporation (Nasdaq: ARDM) today announced positive results from a self-injection study in which healthy naive users successfully administered sumatriptan via its needle-free Intraject(R) system, achieving bioequivalent blood plasma levels to the currently marketed subcutaneous needle-injected product. This clinical trial is part of an ongoing initiative at Aradigm to develop and launch the first needle-free injectable triptan for treatment of migraine and cluster headaches.

"This data confirms that subjects can self-administer using Intraject and gain a clinically relevant outcome," said Dr. Bryan Lawlis, Aradigm's President and Chief Executive Officer. "We believe that this data, combined with the outstanding clinical performance from previous trials, reinforces Intraject as a commercially-significant needle-free platform. In addition, we believe the simplicity of the system will be very important for migraine patients who are frequently cognitively-impaired during their migraine attacks and as a result find injections very difficult to do. This, together with the needle-free advantage, is likely to favorably position this product for the treatment of migraine headache."

The trial was a randomized, open-label, single-dose, crossover study evaluating the pharmacokinetics of sumatriptan at three injection sites in 24 healthy adult male and female volunteers naïve to self-injection with Intraject. Subjects were asked to dose themselves in the thigh, abdomen and arm. The comparability of Intraject to the subcutaneous needle-injected sumatriptan product was established for pooled data across the three injection sites using standard bioequivalence criteria of peak concentration achieved in blood plasma (Cmax), and total drug concentration in blood plasma achieved over time (AUC). Other pharmacokinetic measures were similar between Intraject and the needle-injected product.

Aradigm develops non-invasive delivery systems to enable patients to comfortably self-administer biopharmaceuticals and small molecules that would otherwise be given by injection. The company's advanced AERx(R) pulmonary and Intraject(R) needle-free delivery technologies offer rapid delivery solutions for liquid drug formulations. Current development programs focus on neurological disorders, heart disease, respiratory conditions and cancer. More information about Aradigm can be found at www.aradigm.com.

Except for the historical information contained herein, this news release contains forward-looking statements that involve risk and uncertainties, including clinical results, the timely availability and acceptance of new products, the impact of competitive products and pricing, and the management of growth, 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.

NOTE: AERx and Intraject are registered trademarks of Aradigm.

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(13th December 2004) Aradigm Signs Development and Licensing Agreements for the Treatment of Respiratory Infections

(17th November 2004) Aradigm Announces Results from Clinical Study of Intraject Needle-Free System with Sumatriptan

(13th October 2004) Aradigm Demonstrates Clinical Performance of Intraject Needle-Free System

(28th September 2004) Novo Nordisk Expands Licensing Rights to AERx® iDMS Inhaled Insulin Program from Aradigm and Obtains Full Development and Manufacturing Rights