Brexanolone: an allosteric modulator of GABA-A receptors in the rapid treatment of postpartum depression

Time to re-engage psychiatric drug discovery by strengthening confidence in preclinical psychopharmacology

BACKGROUND

There is urgent need for new medications for psychiatric disorders. Mental illness is expected to become the leading cause of disability worldwide by 2030. Yet, the last two decades have seen the pharmaceutical industry withdraw from psychiatric drug discovery after costly late-stage trial failures in which clinical efficacy predicted pre-clinically has not materialised, leading to a crisis in confidence in preclinical psychopharmacology.

METHODS

Based on a review of the relevant literature, we formulated some principles for improving investment in translational neuroscience aimed at psychiatric drug discovery.

RESULTS

We propose the following 8 principles that could be used, in various combinations, to enhance CNS drug discovery: (1) consider incorporating the NIMH Research Domain Criteria (RDoC) approach; (2) engage the power of translational and systems neuroscience approaches; (3) use disease-relevant experimental perturbations; (4) identify molecular targets via genomic analysis and patient-derived pluripotent stem cells; (5) embrace holistic neuroscience: a partnership with psychoneuroimmunology; (6) use translational measures of neuronal activation; (7) validate the reproducibility of findings by independent collaboration; and (8) learn and reflect. We provide recent examples of promising animal-to-human translation of drug discovery projects and highlight some that present re-purposing opportunities.

CONCLUSIONS

We hope that this review will re-awaken the pharma industry and mental health advocates to the opportunities for improving psychiatric pharmacotherapy and so restore confidence and justify re-investment in the field.

Brexanolone Is the First Drug Specifically for Postpartum Depression

Postpartum depression is a mood disorder that affects up to 20% of women in the first year after childbirth. Symptoms can range from mild depression and anxiety to severe mood alterations and psychosis. A mainstay of treatment has included selective serotonin reuptake inhibitors. However, it can take 2 to 6 weeks for clinical improvement with this approach. In March 2019, the U.S. Food and Drug Administration approved brexanolone, the first medication specifically indicated for the treatment of postpartum depression. Given as an intravenous infusion over the course of 60 hr, brexanolone has the potential to fill an unmet need for women with postpartum depression. In this column, I will provide an overview of brexanolone and discuss administration, adverse effects, and practice implications for nurses who work with childbearing women.

Brexanolone: First Global Approval

Brexanolone (ZULRESSO™) is an intravenously administered, small molecule, neuroactive steroid GABAA receptor positive allosteric modulator that was developed by Sage Therapeutics under license to the University of California for the treatment of postpartum depression (PPD). The formulation is a mixture of allopregnanolone, an endogenous inhibitory pregnane neurosteroid, and sulfobutylether-beta-cyclodextrin (a solubilizing agent). In mid-March 2019 brexanolone received its first global approval in the USA for the treatment of PPD in adult women. This article summarizes the milestones in the development of brexanolone leading to its first approval for the treatment of adult women with PPD.