New tests are set to get underway on patients with traumatic brain injury to test the effectiveness of the hormone progesterone.
The clinical trial will enrol more than 1,000 people with a brain injury over a six year period across 17 medical centres.
Phase III testing comes after Emory School of Medicine and Morehouse School of Medicine researchers found that administering the hormone shortly after trauma may reduce the risk of death and long term disability.
Researchers hope to demonstrate that progesterone treatment is more effective than standard care alone for traumatic brain injury.
Lead researcher David Wright said: "No new treatment for severe traumatic brain injury has been approved in over 30 years.
"We hope to conclude in this national trial that progesterone along with standard medical trauma care works better than standard medical care alone in reducing brain damage."
Meanwhile, professor Douglas Smith of the Center for Brain Injury and Repair at the University of Pennsylvania School of Medicine has indicated that mild trauma, such as concussion, could lead to more serious brain injury symptoms such as persistent cognitive problems.
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