Release issued 17th November 2004

Hayward, California - November 17, 2004 Aradigm Corporation (NASDAQ: ARDM) today announced positive results from a pilot pharmacokinetic study in which sumatriptan delivered via its needle-free IntrajectÒ system was compared to the currently marketed needle-injected subcutaneous sumatriptan product. Sumatriptan is indicated for the acute treatment of migraine headache. Results from the study showed that sumatriptan administered via the Intraject system met all bioequivalence criteria and demonstrated statistically equivalent pharmacokinetics to the marketed injectable product.

"This study provides the final validation of Intraject as the system successfully delivered active drug," said Dr. Bryan Lawlis, Aradigm's President and Chief Executive Officer. We have funded this program to date in order to demonstrate conclusively that Intraject needle-free delivery is a viable replacement for conventional subcutaneous injection, and to accelerate our path to first product launch. In the first half of 2005, we anticipate manufacturing registration lots and preparing for pivotal bioequivalence trials in the second half of the year. We are encouraged that our rapid progress is generating attractive partnering prospects for this product, as well as for other products that are currently marketed or being developed for subcutaneous delivery."

The trial was a randomized, open-label, single-dose, crossover study evaluating the pharmacokinetics of sumatriptan at three injection sites in 18 healthy adult male and female volunteers. Subjects were randomized to receive sumatriptan both by Intraject and by the currently marketed subcutaneous needle-injected sumatriptan product into the abdomen, thigh, and arm.

The comparability of Intraject to the subcutaneous needle- injected sumatriptan product was established at all 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, and there was no significant difference in blood levels between the two products.

"This positive data means that Intraject has the potential to be competitively positioned in the $2 billion triptan market," said Dr. Stephen Farr, Senior Vice President and Chief Scientific Officer of Aradigm. "Rapid absorption is important for achieving rapid relief in the treatment of migraine attacks. To date, the performance of injected sumatriptan has not been equaled by any oral triptan. We expect that patients seeking faster pain relief will be pleased to have an effective option that does not involve a needle."

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 AERxâ pulmonary and Intrajectâ 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.

AERx and Intraject are registered trademarks of Aradigm.

(13th July 2005) Aradigm Advances Development of Intraject Sumatriptan With New Clinical Trial Data

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(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