BioWorld International Correspondent
LONDON British Biotech plc received FDA approval to test its novel thrombolytic, BB-10153, in heart attack patients. The Phase II trial will be conducted by one of the leading groups in the field, the Thrombolysis in Mycocardial Infarction (TIMI) Group, initially at two hospitals in the U.S.
British Biotech, based in Oxford, said it believes BB-10153 can dissolve blood clots without causing bleeding, a common side effect of clot-busting drugs.
The compound is an engineered form of human plasminogen, modified so that it is activated to the fibrinolytic enzyme plasmin by thrombin. As thrombin is produced only at the site of a fresh clot, once activated BB-10153 will dissolve only recently formed or still-forming clots.
“Thrombin-activable plasminogen thus marks a new approach to thrombolysis in which thrombin, the key enzyme in blood clot formation, is utilized to initiate clot destruction,” the company said.
The aim of the trial will be to test the ability of BB-10153 to dissolve clots and restore blood flow in the coronary arteries of heart attack patients, and to determine safety, especially with respect to bleeding. The drug will be administered within six hours of an attack.
BB-10153 has an extended half-life of three to four hours and the company said this means it will persist in the blood as a prodrug, activated only if it encounters fresh or forming blood clots. In addition to dissolving existing clots, it may prevent reocclusion.
The company completed Phase I testing of the compound in 1999, but manufacturing issues held up the start of Phase II. British Biotech said it is actively seeking partners for the development and marketing of the drug.