Medco Research Inc.'s diagnostic to assess myocardialviability can identify those unlikely to benefit fromcardiac bypass surgery, according to two pivotal studiesof the imaging agent.

Based on the results, Medco, of Research Triangle Park,N.C., plans to file a new drug application by the end ofthe first quarter of 1996. The two trials, which togetherenrolled 189 patients (about 120 of whom completed thestudy), focused on predicting surgical outcomes inpatients with coronary artery disease and left ventriculardysfunction who were scheduled for cardiac bypasssurgery.

The product, called ViaScint, is an Iodine-123 iodophenylpentadeconoic acid (IPPA).

"Such an agent for imaging with a gamma camera wouldprovide a widely available and cost-effective alternativeto positron emission tomography imaging of the heart,"said Roger Blevins, Medco's president and chiefoperating officer.

Patients in the study were injected with the radioisotope,followed by early and delayed imaging. A comparison ofthe two allowed investigators to determine whethervarious regions of the heart are metabolizing IPPA.

Those in the study were scheduled to have the surgeryand had a left ventricular ejection fraction of less than 45percent. One objective was to measure improvement inejection fraction, then classify patients as improving ornon-improving and determine the relationship betweenviability and improvement, and non-viability with lack ofimprovement.

Blevins said the results showed a strong negativepredictive ability and a limited positive predictiveaccuracy. Both, he said, were consistent withexpectations. n

-- Jim Shrine

(c) 1997 American Health Consultants. All rights reserved.