TSI Preps for Trials of New Clot-Busting Drug

the occlusive clots. After watching several companies fail, Gurewich went back to the drawing board and kept working on proUK until he came up with a molecule that maintained both its targeting power and its ability to stretch the therapeutic time window.

TSI’s approach combines a mutant form of proUK with a natural plasma inhibitor called C1, which is commonly used to prevent excessive bleeding. The company has demonstrated that C1 promotes the targeting and therapeutic activity of the mutant proUK, “without any detrimental effects on the time it takes to destroy the clot,” Wallace says.

Early human trials with healthy volunteers will start soon and should be completed by the end of this year. The company hopes to be in mid-stage testing with stroke patients in 2013. Rather than taking on Genentech head-to-head, Wallace says, TSI will study its compound in patients who couldn’t be given tPA because of uncertainty about when their strokes occurred.

TSI has raised $8 million in two funding rounds, much of which came from a European trust. That’s enough to get the company through the first round of testing, Wallace says. He says that the company needs to raise another $8 million to $10 million to get through the second round of trials, and it will start looking for a Big Pharma partner after that.

TSI is focusing on stroke for now, but the company’s scientists believe their technology may also be effective in acute myocardial infarction, deep vein thrombosis, and similar disorders where clots are the underlying issue. “Similar to stroke,” Wallace says, “there is a lot of unmet need.”

Author: Arlene Weintraub

Arlene is an award-winning journalist specializing in life sciences and technology. She was previously a senior health writer based out of the New York City headquarters of BusinessWeek, where she wrote hundreds of articles that explored both the science and business of health. Her freelance pieces have been published in USA Today, US News & World Report, Technology Review, and other media outlets. Arlene has won awards from the New York Press Club, the Association of Health Care Journalists, the Foundation for Biomedical Research, and the American Society of Business Publication Editors. Her book about the anti-aging industry, Selling the Fountain of Youth, was published by Basic Books in September 2010.