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U. blood clot study will use controversial research method

SALT LAKE CITY — University of Utah researchers want to study an experimental blood-clotting drug this summer — and you may become a test subject, even if you don't know it.

The drug is called tranexamic acid, or TXA, and it’s known to reduce bleeding in trauma patients, possibly preventing organ failure and death.

Starting this summer, emergency responders will start testing the drug on trauma patients aboard AirMed flights unless they opt-out in advance and wear a bracelet that says they don't want to take part.

Dr. Ram Nirula, the chief of trauma at University of Utah Health Care and a lead investigator of the national trial, said the drug could have big implications for emergency responders in the Intermountain West, where many patients live in rural communities far away from the hub of Salt Lake.

"If they can't get to definitive care to get their injuries taken care of quickly, we need every opportunity to extend that time frame to give them every chance to survive," Nirula said.

In this study, half of AirMed patients will be given the drug; the other half will be given a placebo. Only patients who have suffered severe trauma with risk of significant bleeding will be enrolled.

Nirula said the public “generally understands the need for these studies."

"A lot of it has to do with making sure we inform the public,” he said. “We aren't going to do something that we think is unsafe."

Still, administering the drug to patients who are unable to consent has been controversial in the past.

To conduct the study, researchers need a federal waiver that exempts them from having to get informed consent from patients before administering the drug.

Such studies are “very unusual” and are usually limited to emergency situations involving brain injuries, poisonings or hemorrhaging — circumstances in which patients are usually unable to give consent, according to Dr. Arthur Caplan, director of the division of bioethics at NYU Langone Medical Center.

"There is a need in emergencies to come up with better interventions," said Caplan, adding that waived-consent trials can be the only way to test new drugs and therapies.

“The ethical stance has been that people reasonably would want you to try something if the alternative was a likelihood of dying or severe damaging disability," he added. "When you talk to people, when you survey people, most people say, 'If you don't have anything, try it. Give me a chance.'"

Researchers have been conducting waived-consent studies for the past two decades. Such studies have helped providers identify how much plasma to use in blood transfusions and improved the way the military cares for wounded soldiers on the battlefield, among other things.

But the method is not without controversy.

A study involving an experimental blood substitute called PolyHeme ran aground in 2006 after preliminary data showed the drug was not having an effect.

University Hospital and LDS Hospital, both slated to participate in the study, ultimately did not enroll anybody after the Wall Street Journal revealed links between the product and heart attacks.

Analysis later showed the synthetic blood product had adverse effects — 13.2 percent of blood-substitute patients died in the study compared with 9.9 percent among those who did not receive it.

Such studies need to be carefully scrutinized and widely publicized, according to Caplan. And researchers should be transparent about early results and shut down the study as soon as they get conclusive evidence, he said.

University of Utah Health Care has started calling community members and will hold at least five public meetings to get feedback about the proposed study, according to trauma outreach coordinator Zach Robinson.

"We're excited to be doing this," Robinson said at a news conference Tuesday. "We're excited to tell the public."

University of Utah researchers hope to start the trial — titled the "Study of Tranexamic Acid during Air Medical Prehospital transport," or STAAMP — this summer. The trial will go on for three years unless early data is clear enough to quit early.

The other three centers involved in the study — the University of Pittsburgh, University of Arizona and University of Texas San Antonio — are also in various stages of the research process.

The study has been approved by the University of Utah’s ethics board, and the drug is considered safe and effective, according to Nirula.

An earlier trial tested tranexamic acid in more than 20,000 hospital patients across 40 countries and found that the drug reduced mortality by 1.5 percentage points — a small but significant figure.

The drug worked even better among the most badly injured patients and was more effective the earlier it was given, according to the study.

There is some evidence the drug has a small chance of causing blood clots and seizures, but Nirula said that should not exempt someone from participating in the study.

"If we're talking about life and death versus forming clots or having a seizure, even if I was one of those people I would still want to be part of this study, because I think the opposite of what could happen is worse," Nirula said.

For more information or to get a bracelet to opt out, contact the study team at 801-587-9367 or More information can be found at

University of Utah Health Care members will also be available for questions at several community meetings across the state from April to June.


Twitter: DaphneChen_