An FDA advisory committee voted 17-1 on Friday to recommend the approval of Sage Therapeutics’ postpartum depression drug, brexanolone. If approved—a decision the agency must make by Dec. 19—brexanolone would become the first treatment approved specifically for this type of depression.
The panel, a joint meeting of the Psychopharmacologic Drugs Advisory Committee and the Drug Safety and Risk Management Advisory Committee, also voted 16-2 that Sage had adequately characterized the safety profile of brexanolone and deemed in a unanimous vote that the company had presented substantial evidence showing the drug’s efficacy.
Brexanolone is an analog of the human hormone allopregnanolone. How it actually treats postpartum depression is unknown, but the drug looks to be a “positive allosteric modulator of GABAA receptors with a binding site distinct from benzodiazepines,” a class of psychoactive drugs used to treat conditions such as panic attacks, insomnia, seizures and alcohol withdrawal. It is given to patients in a 60-hour intravenous infusion, requiring both patients and providers to commit to long in-clinic infusions.
In a pair of phase 3 trials, brexanolone achieved its primary endpoint of change in Hamilton Rating Scale for Depression (HAM-D) from baseline.
The FDA outlined its key safety concern in briefing documents released ahead of the meeting: “The Agency’s major safety concern is the observed loss of consciousness/pre-syncope (LOC) during the infusion (6 of 140 women exposed to brexanolone).”
The agency did not think that labeling could solve the issue and so, recommended the use of a risk evaluation and mitigation strategy (REMS) to boost the treatment’s safety. This recommendation was enough for all of the panelists, except one.
“I struggled because of the idea of crossing my fingers and hoping it gets done that way,” said Kim Witczak, the committee’s designated consumer representative.
Others figured that the FDA’s suggestion would be adequate.
Terri Warholak, a professor and assistant dean at the College of Pharmacy at the University of Arizona, Tucson, was concerned about adverse events but thought that they could be addressed with REMS. And Felipe Jain, M.D., a psychiatrist at Massachusetts General Hospital, said he thought the loss of consciousness events were “transient and consistent with the pharmacodynamic profile of the drug.”
If approved, brexanolone would fill a gap in the treatment of postpartum depression, which is currently treated with talk therapy, counseling and/or antidepressants.
“Although there are approved antidepressant medications, none is specifically approved for PPD, and there is little evidence of their efficacy for this condition,” the FDA said in the briefing documents.