483
There is a small window of opportunity when the damage done by a stroke can be minimized by medication. The problem is that the drug, tPA or PLAT, works its magic in less than 10 percent of all stroke victims, and must be administered quickly. For people who live far from hospitals and for those who aren’t good candidates to receive the drug because of its side effects, an Israeli solution is on the way.
Thrombotech is testing its “piggyback” drug — a synthetic peptide that binds with tPA and seems to cancel its potentially dangerous side effects while greatly extending the timeframe within which it can work to dissolve blood clots in the vascular system of the brain.
The company was founded in 2000 based on the research of Hebrew University’s Prof. Abdel-Raouf Hijazi, an Israeli-Arab. Pre- and early clinical data suggest that Hijazi’s formula can significantly reduce the effects of a stroke by making tPA applicable to a much wider population.
Right now its use is very limited because of the small time window and because it can cause brain bleeding or edema.
“It’s still only relevant for a small subset of people,” says Thrombotech’s CEO Ruth Ben-Yakar.
She is confident that Thrombotech’s drug, currently called THR-18, would allow up to 85% of all stroke victims to receive tPA, and by consequence avoid long-term damage from a stroke, such as paralysis.
"Anything higher than 10% is good for us,” Ben-Yakar says. Patients can take TH-18 up to nine hours after a stroke. “It could increase the number of patients that can take [tPA] today based on the symptoms or the severity of the stroke.”
Phase I toxicity tests were done on human volunteers at Hadassah University Medical Center in Jerusalem, which is affiliated with the Hebrew University.
In hospital ERs by 2017?
The company has started a Phase II trial involving stroke patients. In the double-blind study, some patients receive tPA and TH-18, while others receive tPA and a placebo in order to measure the effect of adding TH-18.
Thrombotech is waiting for approval to start similar studies in Europe and in the United States.
Ben-Yakar explains that Thrombotech attacks the problem from a different angle than other companies that are trying (so far unsuccessfully) to come up with a tPA alternative.
“The stroke area is a very dangerous field for companies,” she says. Rather than looking for a different neuroprotective agent, “we belong to a different group by working to improve something that has been accepted for many years.”
TH-18 works by modifying the tPA molecule to prevent chemical interactions between tPA and non-embolic targets in the brain. This allows tPA to dissolve blood clots without causing bleeding.
Thrombotech also has good reason to hope that the same pharmaceutical agent could be effective for cardiovascular and high blood pressure indications.
Based in Nes Ziona with a staff of six people, this tiny company is looking to address a $3 billion market. Stroke is the third leading cause of death in the United States, where it kills about 140,000 people every year.
Some of Thrombotech’s shareholders include Clal Biotechnology Industries, Ofer Hi-Tech and Hadasit Bio-Holdings. If all goes well, Ben-Yakar says, the new drug could be on the market by 2017.