By Frances Bishopp
Sonus Pharmaceuticals Inc., seeking an expanded label for its lead product, EchoGen, reported results from a Phase IIIb clinical trial that demonstrate its EchoGen-enhanced echocardiography for measurement of left ventricular volume and ejection fraction compares favorably with magnetic resonance imaging in diagnosing severely depressed cardiac function.
Sonus, of Bothell, Wash., submitted a new drug application (NDA) to the FDA for EchoGen on Sept. 5, 1996, for measuring endocardial border delineation in echocardiography and for liver, kidney and vascular radiology.
EchoGen is a fluorocarbon-based ultrasound contrast agent developed to enhance the clinical utility and cost-effectiveness of ultrasound procedures in radiology and cardiology. Ultrasound currently is the only imaging procedure without an effective FDA-approved contrast agent for broad clinical uses.
The submission of the NDA triggered $4 million in milestone payments from Abbott Laboratories, of Abbott Park, Ill., under terms of an agreement granting Abbott rights to market EchoGen in the U.S. Sonus is getting up to $48 million, while keeping nearly half of net revenues as part of the collaboration.
In the Phase IIIb trial, compared to magnetic resonance imaging (MRI), 32 patients (91 percent) with EchoGen-enhanced echocardiography were correctly classified into appropriate ejection fraction (EF) categories to visualize 98 percent (413 of 420) of the endocardial border segments.
In the 20 patients with depressed EF, the reliability of echocardiography for the discrimination of a severely depressed vs. mild to moderately depressed EF was dramatically improved in the EchoGen-enhanced studies (90 percent) vs. the unenhanced studies (60 percent).
EchoGen is a liquid emulsion injected into the vein, Steven Quay, president and CEO of Sonus, said. It forms tiny microbubbles and goes throughout the vascular systems to give contrast for 10 to 15 minutes.
Quay said Sonus has a June 30, 1997, advisory panel meeting for the approval of EchoGen. "If they recommend approval, the Wall Street analysts are projecting approval in the first quarter of 1998," Quay said.
Sonus also is collaborating with Japan-based Daiichi Pharmaceutical Co. Ltd., in the Pacific Rim.
As of Dec. 31, 1996, the company had approximately $25 million in cash on hand and no net loss was reported. *