In its largest financing to date, ImaRx Therapeutics Inc. raised $15 million through a private placement of common stock to support development of its lead clot-busting products in ischemic stroke and peripheral vascular diseases.

Funds will be used "mainly for advancing clinical trials for our products in treating stroke," said Greg Cobb, chief financial officer for Tucson, Ariz.-based ImaRx. Money also will support general corporate purposes and pay for an upcoming product acquisition, though the company would not release details at this time.

In ischemic stroke, ImaRx has three products in clinical development. The first is a thrombolytic agent called Prolyse.

Prolyse is a recombinant prourokinase thrombolytic product that has completed the first of two Phase III studies needed for the submission of a new drug application.

A second product, SonoLysis, was developed using ImaRx's nanotechnology-based platform. It's designed to use the company's MRX0815 nanobubbles plus ultrasound to dissolve clots in stroke patients without invasive surgery or systemic drug products.

"We'll be kicking off a Phase II study with that in the second quarter of 2006," Cobb told BioWorld Today.

"We also have a combination product, SonoLysis Prolyse, which is a Phase II study," he said, with results expected during the second quarter of next year. That product also uses nanobubbles, ultrasound and thrombolytic therapy to dissolve clots.

ImaRx's lead product, Open-Cath-R (recombinant urokinase), has completed testing in two Phase III trials in patients suffering from occluded catheters. The company is working to complete the manufacturing transfer process. In the meantime, it will evaluate "that market opportunity and, most likely, find a partner," Cobb said.

Earlier this year, the company launched its NanO2 Nanobubble Therapeutics program to develop portable emergency oxygen delivery treatments that will allow doctors to treat patients with hemorrhagic shock on the battlefield or in other emergency situations. That program was developed around ImaRx's oxygen delivery patents, plus four patents sublicensed from Bothell, Wash.-based Sonus Pharmaceuticals Inc.

ImaRx's last financing in March of this year brought in $7 million, which was expected to sustain operations through October, add some key personnel and fund further development of SonoLysis in stroke trials.