(RxWiki News) A hormone therapy that showed promise in past research may be ineffective in treating patients with traumatic brain injuries. Still, researchers remain hopeful that better treatments are on the horizon.
A new study found that progesterone treatment did not increase survival or improve function in patients with traumatic brain injuries. But, even without the progesterone, half the patients made a good recovery.
Progesterone is a hormone present in both women and men. It is important in brain development and has been shown to have a protective effect on brain tissue. Past studies have shown that some patients with traumatic brain injury lived longer when given progesterone.
The standard treatment for patients with traumatic brain injury is to repair the damage to brain vessels. This is followed, if possible, by rehabilitation to improve mobility, speech and brain function.
“These results are plainly disappointing,” said researcher David Wright, MD, of Emory University in Atlanta, in a press release. Dr. Wright was the lead author on an earlier study on traumatic brain injury. “We were not able to translate [past findings] to a multi-center clinical trial with human traumatic brain injury."
Brett E. Skolnick, PhD, of the Department of Neurosurgery at the Hofstra School of Medicine in Manhasset, NY, led the current study.
This study included a total of 1,195 men and women with severe traumatic brain injury. Patients were considered to have severe traumatic brain injury if they scored 8 or below on the Glasgow Coma Scale. Scores on this scale ran from 3 to 15. Lower numbers indicated lower levels of consciousness — or more severe traumatic brain injury. About 62 percent of the patients in this study sustained their traumatic brain injury in a car or motorcycle accident.
About half were given progesterone, starting within eight hours of their injury. Progesterone was given intravenously (into the vein) for four days. About half the patients in the study received a fake solution, called a placebo.
Dr. Skolnick and team wanted to see whether progesterone improved recovery from severe traumatic brain injury. They evaluated this through interviews about the patients' level of disability or handicap three and six months after the injury.
These researchers also looked at survival one and six months after the traumatic brain injury occurred.
After six months, the percentage of patients who reported good recovery or moderate disability was about the same (50 percent) in the group receiving progesterone and the group receiving the placebo. Survival rates were also similar in the two groups.
Dr. Skolnick and colleagues said one reason for their results might be because every person’s traumatic brain injury is different. The location and extent of the brain injury and time before the patient was treated varied with each patient.
Lee H. Schwamm, MD, of Massachusetts General Hospital and Harvard Medical School in Boston, suggested another reason for these results in an editorial about the study.
Dr. Schwamm said the odds of the new study showing benefit to patients on progesterone were low because past studies showed a small effect with a small number of patients. The fact that patients on a placebo alone showed a 50 percent improvement meant the progesterone would have to work extremely well to show an improvement greater than that, Dr. Schwamm said.
Dr. Schwamm said large follow-up studies should be built on strong early data. Better collaboration between researchers — as well as reporting, sharing and pooling early data — would build stronger, more meaningful research studies, he wrote.
"These changes may result in more extensive and costlier early-phase work ... but eventually greater numbers of successful phase 3 trials," Dr. Schwamm said.
Both the study and the editorial were published online Dec. 10 in the New England Journal of Medicine.
The National Institute of Neurological Disorders and Stroke funded the study.
Dr. Wright received royalties from a patent related to progesterone for the treatment of traumatic brain injury. No other authors disclosed conflicts of interest.