Tucson, AZ – July 11, 2005 – ImaRx Therapeutics, Inc. announced today that it has launched its NanO2 Nanobubble Therapeutics program to develop portable emergency oxygen delivery treatments that will enable physicians to treat patients with hemorrhagic shock in the battlefield or other emergency situations. The program was developed around ImaRx's existing suite of oxygen delivery patents and advanced nanobubble emulsion technologies in addition to four U.S. patents that the company has exclusively sublicensed from Sonus Pharmaceuticals, Inc. The patents cover compositions of matter and methods of using oxygen delivery for treatment of disease.

“ImaRx has strengthened our existing oxygen delivery patent estate with several patents we sublicensed from Sonus. Combined with our expertise in developing specialized nanobubble formulations, the patents form the basis of our new NanO2 Nanobubble Therapeutics program,” said Evan Unger, M.D., ImaRx's President and CEO.

Unger added, “We are currently evaluating the use of oxygen delivery nanobubbles to treat a variety of critical diseases and conditions including ischemia, shock and cancer. One of the most interesting potential applications of our NanO2 therapeutics is in replacing the bulky oxygen tanks military physicians currently use in the battlefield for treating patients who have experienced massive blood loss and are not getting enough oxygen to tissues in the body.”

Claes Lundgren, M.D., Ph.D., professor of physiology and biophysics, SUNY-Buffalo, who is known for his invention of Nicorette® gum and is an inventor of two of the Sonus patents sublicensed to ImaRx said, “Nanobubbles are highly efficient at oxygen delivery – in fact 400 times more effective than red blood cells.”

Dr. Lundgren presented results from studies in animal models at the American Heart Association's (AHA) Resuscitation Science Symposium in November 2004 showing that severe shock resulting from as much as 50 percent blood loss was treated completely effectively using very small doses of nanobubbles. The presentation was selected by the AHA as among the top ten percent given at the meeting.

Commenting on the study, Dr. Lundgren said, “The results from our study indicate that nanobubbles are a viable, completely synthetic alternative to blood substitutes. Because nanobubbles are made without potentially dangerous blood-based products and result in complete resuscitation both at very low doses of about 30 cc and without the use of supplemental oxygen, they may be ideal for use in emergency situations where a portable oxygen delivery treatment is required.”

To treat hemorrhagic shock, a nanobubble emulsion is injected into the bloodstream where it expands into nanobubbles that circulate through the lungs. The nanobubbles imbibe and carry as much as 400 times more oxygen in the lungs than red blood cells and deliver it to poorly oxygenated tissues. Unlike other oxygen delivery therapeutics, chemical components of which can remain in the body for months or even years, remaining gas from the nanobubbles is quickly exhaled by the lungs.

Headquartered near Seattle , Washington , Sonus Pharmaceuticals, Inc. is focused on the development of therapeutic drugs that may offer improved administration, safety, tolerability and effectiveness for the treatment of cancer and related conditions. The Company's lead product candidate is TOCOSOL® Paclitaxel, a novel formulation of the widely prescribed anti-cancer drug paclitaxel.  TOCOSOL Paclitaxel has been designed to overcome the limitations associated with Taxol® and generic paclitaxel-based chemotherapy, including long infusion times, undesirable or treatment-limiting side effects as well as time consuming and expensive preparation of the products prior to administration.

ImaRx, a privately-held biopharmaceutical company, develops NanoInvasive™ therapies for the treatment of cardiovascular disease, CNS disease, and cancers.  The Company's lead product, SonoLysis™, combines the power of ultrasound with proprietary nanobubbles to locally dissolve blood clots without the use of invasive surgery or potentially dangerous lytic drugs.  SonoLysis is currently in a Phase II study for stroke and a Phase I/II study for peripheral arterial occlusive disease.  For more information, please visit www.imarx.com .