A large phase III clinical trial has shown that treatment of acute traumatic brain injury with progesterone provides no significant benefit to patients when compared with a placebo, according to an Emory University press release.
The ProTECT III study involved 49 trauma centers across the United States, and it took place between July 2009 and November 2013. It was funded by the National Institute of Neurological Disorders and Stroke and organized as part of the Neurological Emergencies Treatment Trials (NETT) network. The study was originally planned to include 1,140 patients, but it was stopped after 882 patients because safety monitors determined that additional enrollment would be futile.
In the study, the progesterone-treated group and the placebo-treated group showed no significant difference in survival or favorable outcomes as measured by improvement in Glasgow Coma Scores. Favorable outcomes occurred in 51% of those who received progesterone and 56% of those who received a placebo. Mortality after 6 months was 18.8% for progesterone and 15.7% for placebo. The results of the trial were published online by the New England Journal of Medicine.
“These results are plainly disappointing,” said David Wright, MD, associate professor and vice chair for research in emergency medicine at Emory University School of Medicine. “The preclinical data on progesterone’s neuroprotective effects are compelling, but we were not able to translate them to a multi-center clinical trial with human traumatic brain injury.”
Animal studies were promising
The rationale for testing progesterone grew out of the observation that women tend to respond to treatment and recover better than men after TBI. Both men and women naturally produce progesterone. The steroid hormone is important for brain development as well as reproductive functions.
Many research teams have found in animal experiments that progesterone can protect brain cells from the toxic environment that emerges after traumatic injury. Two smaller clinical trials of progesterone in traumatic brain injury also gave encouraging results. Read the Full Press Release
Similar study shows same disappointing results
Separately, the industry-funded SYNAPSE trial also showed that progesterone provides no clinical benefit in the treatment of severe TBI. Trial results were published in the New England Journal of Medicine.