The results from a Phase II trial on RheothRx Injection as anadjunct to coronary angioplasty in the treatment of heartattacks supported the drug's safety profile, but also showedthat there was no difference in efficacy between the treatmentand placebo groups.
However, the drug did seem to have a significant positive effecton myocardial infarction (MI) patients being treated withthrombolytics.
The data from the first trial were presented Tuesday at theannual meeting of the American Heart Association in Atlantaby Cindy Grines of the William Beaumont Hospital in Royal Oak,Mich.
This is the first of two Phase II clinicals on RheothRx, a non-ionic surfactant copolymer discovered by CytRx Corp.(NASDAQ:CYTR) of Norcross, Ga., and being developed by thecompany's licensee, Burroughs Wellcome Co. The copolymer isused to coat blood vessels to improve blood flow.
Results from the second Phase II trial, which assessedRheothRx as an adjunct to thrombolytic therapy in heart attackpatients, will be presented next March at the annual meeting ofthe American College of Cardiology.
In the angioplasty study, 150 patients with acute MI wererandomized 2:1 to receive either RheothRx Injection or placeboin addition to the angioplasty procedure. The clinical endpointsfor this study included the rate of reinfarction, left ventricularfunction, the size of the infarct, myocardial salvage, and, ofcourse, safety.
"This is one of the first trials in which one of the outcomes wasto assess the effect of treatment on infarct size," explained R.Martin Emanuele, CytRx's vice president of preclinical researchand development. "The results showed that there was nodifference due to RheothRx treatment," he added. "Theendpoints were absolutely equivocal."
This second Phase II trial, which was completed in the earlyfall, compared outcomes of MI patients who received treatmentwith either recombinant tissue plasminogen activator (t-PA) orstreptokinase as well as RheothRx (or placebo). The clinicalendpoints for this trial were the same as those for theangioplasty trial, Emanuele said.
"The results are substantially more promising (than in theangioplasty trial)," Emanuele told BioWorld. So promising, infact, that Burroughs Wellcome intends to initiate a worldwide,9,000-patient Phase III study of RheothRx Injection, used aloneor in combination with thrombolytics, in patients with acuteMI.
In those trials, the primary clinical endpoint will be acomposite, measuring the incidence of infarction, shock anddeath, explained Emanuele. The international study could beginas early as the first quarter of 1994.
-- Jennifer Van Brunt Senior Editor
(c) 1997 American Health Consultants. All rights reserved.