Brexanolone achieved the primary endpoint in both trials, a mean reduction from baseline in the Hamilton Rating Scale for Depression (HAM-D) total score compared to placebo at 60 hours (Study 202B: p=0.0242 for 90 µg/kg/h dose and p=0.0011 for 60 µg/kg/h dose; Study 202C: p=0.0160 for 90 µg/kg/h dose).
Patients treated with brexanolone demonstrated mean reductions from baseline in HAM-D total scores of 14 to 20 points at 60 hours maintained to 30 days in both trials. Brexanolone was generally well tolerated and showed a similar safety profile as seen in earlier studies.
PPD is a common biological complication of childbirth affecting a subset of women typically commencing in the third trimester of pregnancy or within four weeks after giving birth. It is estimated that PPD affects approximately 10 to 20 percent of women giving birth in the U.S. and up to half of these cases may go undiagnosed without proper screening. There are no approved therapies for PPD and there is a clear unmet medical need for treatment.
“PPD is commonly viewed as a disorder solely experienced by the mother, but it also seriously impacts the child and family members – both immediate and extended,” said Dr. Samantha Meltzer-Brody, M.D., M.P.H., associate professor and director of UNC Perinatal Psychiatry Program of the UNC Center for Women’s Mood Disorders and primary investigator of the studies.
“Symptoms of PPD should not be overlooked by new moms or those in their support networks and the healthcare community should encourage discussion and appropriate action. These data meaningfully advance our understanding of PPD and may prompt medical professionals to evaluate how PPD is perceived, identified and treated within their practices in the future. In these studies, brexanolone provided a profound and durable effect over the study period that could be an important step in potentially changing the way health care providers think about treating this disorder.”
The Hummingbird Phase 3 program included two Phase 3, multicenter, randomized, double-blind, parallel-group, placebo-controlled trials designed to evaluate the safety and effectiveness of brexanolone in women with moderate and severe PPD.
Entry criteria for participants included depressed mood and/or loss of interest and associated symptoms of depression, including appetite problems, sleep problems, motor problems, lack of concentration, loss of energy, poor self-esteem and suicidality that began no earlier than the third trimester and no later than the first four weeks following delivery.
“This is the first Phase 3 program conducted specifically in women with PPD and these results exemplify the value of Sage’s distinct approach to clinical research,” said Jeff Jonas, M.D., chief executive officer of Sage.
“We are pleased with the findings, specifically the rapid onset of action and duration of effect observed in all arms of the Hummingbird program. We believe the data represent an unprecedented opportunity in the development of treatments for PPD, and may serve as the catalyst for a paradigm shift in how the disease is approached and, if approved, may change how PPD is treated.”
“Today illustrates what an exciting time it is in CNS research and drug development,” said Steve Kanes, M.D., Ph.D., chief medical officer of Sage. “Sage is deliberately pursuing a translational clinical strategy that can expedite medical innovation and potentially transform the lives of patients. This strategy begins with open label trials in a carefully selected disease indication, such as PPD, where patients are in need of transformative treatment options. Our approach seeks to establish signals for safety and activity and if a signal is observed, we move efficiently into later stage development. Our brexanolone research for a treatment in PPD followed this path, resulting in the successful data we are announcing today.”
Summary of Top-line Brexanolone Phase 3 Results
Effect on Postpartum Depressive Symptoms:
In both trials at all doses, brexanolone achieved the primary endpoint, a significant mean reduction from baseline in the HAM-D total score at 60 hours compared to placebo.
Study 202B – Patients with severe PPD (n=122):
Patients were randomized to one of three treatment groups (brexanolone 90 μg/kg/hour, brexanolone 60 μg/kg/hour, or placebo) on a 1:1:1 basis.
Brexanolone 90 μg/kg/hour treatment was associated with a statistically significant mean reduction in HAM-D total score of 17.7 points from baseline compared with a 14.0 point mean reduction in HAM-D total score associated with placebo (p=0.0242).
Brexanolone 60 μg/kg/hour treatment was associated with a statistically significant mean reduction in HAM-D total score of 19.9 points from baseline compared with a 14.0 point mean reduction in HAM-D total score associated with placebo (p=0.0011).
Statistically significant differences in the reduction in HAM-D total score of brexanolone versus placebo were first observed at 48 hours and the effect at 60 hours was maintained through the 30-day follow-up with statistical significance for both brexanolone dose groups.
Improvement in the Clinical Global Impression – Improvement scale (CGI-I) at 60 hours was consistent with the primary endpoint (p=0.0096 for 90 µg/kg/h dose and p=0.0124 for 60 µg/kg/h dose).
Study 202C – Patients with moderate PPD (n=104):
Patients were randomized to one of two treatment groups (brexanolone 90 μg/kg/hour or placebo) on a 1:1 basis.
Brexanolone treatment was associated with a statistically significant mean reduction in HAM-D total score of 14.2 points from baseline at 60 hours (p=0.0160) compared with a 12.0 point mean reduction in HAM-D total score associated with placebo.
Statistical significance was first observed at 48 hours and remained through Day 7, but not at Day 30. However, the effect observed at 60 hours in the brexanolone group was maintained through the 30-day follow-up.
Improvement in the Clinical Global Impression – Improvement scale (CGI-I) at 60 hours was consistent with the primary endpoint (p=0.0005).
Safety and Tolerability:
Brexanolone was generally well tolerated in both studies with similar rates of adverse events across all treatment groups.
In each trial, there was one patient who experienced a serious adverse event; neither required hospitalization and one of which was deemed by the investigator not to be study-drug related.
The most common adverse events in the studies were headache, dizziness, and somnolence.
Detailed study results, including additional secondary endpoints, will be submitted for presentation at an upcoming medical meeting and for publication. Sage believes these data will be sufficient to support submissions of regulatory applications seeking approval of brexanolone for PPD. Sage plans to file a New Drug Application (NDA) with the U.S. Food and Drug Administration (FDA) in 2018.