Sage Therapeutics has received approval for brexanolone (Zulresso) for the treatment of postpartum depression (PPD). The medicine is the sole treatment available for what is the most common medical complication of childbirth, affecting around 400,000 women annually in the U.S.
The approval of brexanolone is based on results from three multicenter, randomized, double-blind, parallel-group, placebo-controlled trials. The studies were designed to evaluate brexanolone’s safety and effectiveness in women aged 18 to 45 years old with moderate and severe PPD, six months or less postpartum at time of screening, and with symptom onset no earlier than the third trimester and no later than the first four weeks after delivery.
Brexanolone achieved the primary endpoint in all trials at all doses–a significant mean reduction from baseline in the Hamilton Rating Scale for Depression total score at 60 hours compared to placebo. In addition, a reduction of symptoms was seen as early as 24 hours, and the drug maintained its effect through the 30-day follow-up.
The most common adverse events in the studies were sleepiness, dry mouth, loss of consciousness, and flushing.
Brexanolone is an allosteric modulator of both synaptic and extrasynaptic GABAA receptors. Allosteric modulation of neurotransmitter receptor activity causes varying degrees of desired activity as opposed to complete activation or inhibition of the receptor. The drug is administered by continuous intravenous infusion into the vein, and the infusion lasts for a total of 60 hours.
Brexanolone is expected to be available in the U.S. by late June 2019, and it has also been granted PRIority MEdicines (PRIME) designation by the European Medicines Agency.
Source: Sage Therapeutics, March 19, 2019