Though experts greeted initial efforts with skepticism, the results from a recent stage three, worldwide clinical trial indicate that the hormone progesterone may play a key role in treating patients who have suffered a traumatic brain injury. Progesterone is a naturally occurring developmental hormone that, among other things, plays an important role in gestation.

For decades, researchers and physicians have attempted to develop an effective acute treatment for traumatic brain injuries. Many drugs have shown promise, but none have made it past a stage three clinical trial. Don Stein, the Emory University neuroscientist in charge of the progesterone study, suggests that the reason so many other treatments have failed is because researchers have focused too much on treating single, isolated genes or pathways in the hope of developing a “magic bullet.” According to Stein, this is not the best way to approach treatment for traumatic brain injuries.

In Stein’s view, brain injuries are best viewed as systemic diseases that impact many different parts of a person’s body. The initial injury triggers an inflammatory response in the body that can cause swelling, tissue damage and even cell death. What makes progesterone particularly promising as a potential treatment for traumatic brain injuries is that it does not target one particular pathway or neural receptor. Instead, the hormone helps to stop the body’s inflammatory response and even stimulates neural regeneration and repair.

In a stage two clinical trial, researchers test new treatments on a small number of patients primarily to demonstrate safety. In the case of progesterone, Stein’s team discovered that the drug was not only safe, but also effective. Of those treated during stage two, researchers noted a 50 percent reduction in death and a marked functional improvement in some patients. The evidence was enough to justify moving forward to stage three, which involves large scale testing to determine efficacy, study side effects and to compare to other existing treatments.

Stein is hopeful that his research will prove that progesterone is a safe, effective treatment for patients who have suffered a traumatic brain injury. He is also taking steps to determine whether the drug proves helpful in treating both pediatric brain injuries and strokes. Initial research also indicates that the drug may prove effective in treating some forms of brain cancer. Overall, Stein’s work could prove to be extremely important to helping those with severe brain injuries regain function and improve the quality of their lives.