BTG's varicose vein treatment found safe in trial
LONDON, March 17 (Reuters) - British biotech firm BTG Plc's (BGC.L) most important pipeline product, a varicose vein treatment called Varisolve, is safe for use in patients with a common heart defect, according to preliminary trial results.
In more than 90 percent of the 28 patients studied so far, tiny bubbles were detected in the blood during the treatment procedure but no neurological, visual or cardiac changes were observed, researchers said on Monday.
The U.S. Phase II safety study will continue until 50 patients have been treated and monitored.
The U.S. Food and Drug Administration requested the trial to see if there was any risk that microbubbles used in Varisolve -- an injectable foam made with carbon dioxide -- could pass into arteries and create problems in the brain.
Patients with a right-to-left shunt in their hearts -- a common, usually asymptomatic heart defect affecting around one in four people -- may be at increased risk because bubbles could go to the brain or heart without being filtered in the lungs.
The results being presented at the annual meeting of the Society of Interventional Radiology in Washington are reassuring.
"We believe that the carbon dioxide-based foam used in Varisolve will be totally safe due to the small size of the bubbles, the consistency of the foam and the solubility of carbon dioxide," said lead researcher Dr John Regan of Wake Forest University Baptist Medical Center.
Varisolve, if finally approved, would be an alternative to painful surgery for the estimated 150 million people worldwide who suffer from varicose veins. Some analysts have forecast it could eventually make annual sales of up to $1 billion.
BTG expects the ongoing Phase II safety study to be completed by the middle of this year. (Reporting by Ben Hirschler; Editing by Jason Neely)
