Reunion Neuroscience Inc. Announces $103 Million Series A Financing Co-Led by MPM BioImpact and Novo Holdings

Company is advancing RE104, its proprietary, clinical-stage serotonergic psychedelic drug candidate designed as a safe, fast-acting, short duration therapy to provide lasting benefits to patients with underserved mental health disorders

Financing will support the “RECONNECT” Phase 2 clinical trial for RE104 in postpartum depression (PPD) and expansion into other psychiatric indications of high unmet need, including adjustment disorder in cancer (ADC)

MORRISTOWN, New Jersey, May 2, 2024 – Reunion Neuroscience Inc., a clinical-stage biopharmaceutical company committed to pushing the boundaries of neuroscience, today announced the close of a $103 million Series A financing co-led by MPM BioImpact and Novo Holdings, with participation from Arkin Bio Capital, Mitsui & Co. Global Investment, Plaisance Capital, FemHealth Ventures, and Palo Santo.

“This financing is a significant milestone for Reunion Neuroscience, and we are grateful to have the backing of MPM BioImpact and Novo Holdings, as well as a syndicate composed of top-tier institutional healthcare investors,” said Greg Mayes, President and Chief Executive Officer of Reunion. “Their collective support reflects Reunion’s potential to meaningfully transform mental health treatment for the large population of patients underserved by the treatment paradigm available under the current standard of care. We are committed to unlocking the full potential of RE104 to improve the lives of patients and families in our mission to address the worldwide mental health crisis.”

“Reunion is leading the charge to dramatically shift the way severe mental health disorders are treated,” said Dr. Ansbert Gadicke, M.D., Managing Partner of MPM BioImpact. “We are proud to back Reunion’s world-class team of experienced neuroscience drug developers and support the clinical advancement of RE104, which has the potential to provide patients with meaningful and durable antidepressive effects.”

“We see a significant opportunity for RE104 to become a best-in-class therapy and are deeply encouraged by its potential to improve outcomes for patients facing limited treatment alternatives in postpartum depression and other mental health disorders,” said Natalie Sacks, M.D., Venture Partner in the Venture Investments group at Novo Holdings US. “We look forward to supporting the Reunion team as they bring innovative science to an area of high unmet need.”


RE104 and Clinical Programs

The Company’s lead asset, RE104, is a proprietary, potential best-in-class, patented prodrug of 4-OH-DiPT. RE104 targets the serotonin 2A receptor (5HT2AR), which is the recognized target for the antidepressant effects of psychedelic compounds. As psychedelic drugs require monitoring by trained healthcare providers, per recent FDA Guidance (June 2023), Reunion designed RE104 to deliver a short duration psychedelic experience and require only about half a day in-clinic, a significantly shorter time commitment than required for longer duration psychedelics, like psilocybin and MDMA.

In a Phase 1 study, RE104 produced a psychedelic, psychoactive state similar in intensity and quality to psilocybin, but lasting only about half the time (3-4 hours) while demonstrating a similar, favorable safety profile.

Reunion expects to start enrolling patients this quarter in the RECONNECT Trial, a Phase 2, Multicenter, Randomized, Double-Blind, Parallel-Group, Active Dose-Controlled study evaluating RE104 in moderate and severe PPD patients (NCT06342310). Results from the RECONNECT Trial are expected in Q2 2025.

PPD is a form of major depression that is estimated to affect about 10-15% of all mothers of newborns. The leading underlying cause of pregnancy-related death, accounting for 23% of pregnancy-related death, is mental health conditions. This includes deaths due to suicide and overdose/poisoning related to substance use disorder (Centers for Disease Control and Prevention [CDC], 2022). Women suffering from PPD often experience significant changes in mood, appetite and sleep contributing to feelings of hopelessness, lack of concentration, loss of energy, poor self-esteem and maternal disinterest. While there have been recent developments in treatment options for PPD, there continues to be a significant unmet need for a solution that offers improved safety and tolerability, a faster onset of action, greater efficacy after only a single dose, with limited interruption in breastfeeding and a faster return to normal daily activities.

Reunion is actively investigating the use of RE104 in additional neuropsychiatric indications, including adjustment disorder in cancer (ADC), where there remains a significant unmet need that is not addressed by the current standard of care. ADC is a maladaptive response to a cancer diagnosis persisting for longer than two weeks that is considered disproportionate to the magnitude of the stressor. It is estimated that 40% of cancer patients develop a mood disorder.


About Reunion Neuroscience Inc.

Reunion Neuroscience is committed to pushing the boundaries of neuroscience to develop innovative therapeutic solutions for postpartum depression (PPD) and other underserved mental health disorders. In August of 2023, Reunion Neuroscience was acquired by MPM BioImpact, a world-leading biotechnology investment firm with three decades of experience creating and investing in innovative biotechnology companies seeking to deliver transformative therapies to patients. As part of the MPM BioImpact portfolio, the Company is evaluating its lead asset, RE104, a proprietary, potential best-in-class, serotonergic psychedelic compound and the only 4-OH-DiPT prodrug in clinical development, as a potential treatment for postpartum depression, (NCT06342310), that could provide rapid symptom relief and durable efficacy. Reunion is actively investigating the use of RE104 in additional neuropsychiatric indications where there remains a significant unmet need that is not addressed by the current standard of care.

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