AbbVie to Acquire Gilgamesh Pharmaceuticals’ Bretisilocin, a Novel, Investigational Therapy for Major Depressive Disorder, Expanding Psychiatry Pipeline

Key Takeaways:

• AbbVie will acquire bretisilocin, a novel, investigational therapy for MDD.
• Bretisilocin is a short-acting 5-HT2A receptor agonist and 5-HT releaser.
• Clinical trials showed a notable -21.6 point change in MADRS scores at 10 mg.
• The therapy is designed to reduce the length of the psychoactive experience.
• Bretisilocin was well tolerated, with no serious adverse events reported.

Introduction

AbbVie has entered into a definitive agreement to acquire Gilgamesh Pharmaceuticals’ lead candidate, bretisilocin, a novel compound designed to treat moderate-to-severe major depressive disorder (MDD). The move underscores AbbVie’s deepening commitment to mental health solutions at a time when innovative approaches to treating depression are increasingly critical.

A Next-Generation Psychedelic Therapy

Bretisilocin (GM-2505) offers a next-generation approach to psychedelic therapy, targeting the 5-HT2A receptor while also releasing serotonin (5-HT). This dual mechanism is central to its ability to produce rapid and durable antidepressant effects while maintaining a shorter duration of psychoactive experience compared to other substances in this class.

Clinical Data and Findings

A recent Phase 2a trial reported notable topline results:
| Dosage | MADRS Score Change | |———————-|———————| | 10 mg (bretisilocin) | -21.6 | | 1 mg (comparator) | -12.1 |

At Day 14, the higher dose group showed a statistically significant improvement (p = 0.003) in depressive symptoms. The compound was well tolerated and did not produce any serious adverse events, which supports further exploration and development.

Looking Forward

Psychedelic-based treatments have gained traction for their potential to address challenging psychiatric conditions. However, long-duration sessions and intensive psychoactive experiences often limit their clinical utility. Bretisilocin’s design aims to alleviate these concerns by shortening the psychoactive experience while preserving a lasting therapeutic effect, potentially broadening its adoption and access for patients.

Quote from AbbVie

“The field of psychiatry represents one of the most challenging areas in medicine, with a significant need for innovative solutions,” said Roopal Thakkar, M.D., executive vice president, research and development and chief scientific officer at AbbVie. She noted that this acquisition “underscores our commitment to broadening and enhancing psychiatric care by investing in novel treatment approaches with the potential to reach patients for whom other treatments have been ineffective.”

Conclusion

AbbVie’s decision to invest in bretisilocin marks a noteworthy step in the evolving landscape of depression treatment. With strong Phase 2 data and a design that potentially overcomes key obstacles in psychedelic therapy, bretisilocin could signal a new direction for research and care in MDD, offering hope to those who struggle with existing treatment options.