Reunion Secures $103M for Postpartum Depression Psychedelic Drug

Reunion Neuroscience, a pioneer in psychedelic drug development, has successfully secured $103 million in Series A funding. This newly raised capital is earmarked for advancing its primary candidate, RE104, specifically targeting postpartum depression.

The financing round saw significant contributions from Novo Holdings and MPM BioImpact, who jointly led the effort. Other notable participants include Arkin Bio Capital, Mitsui & Co. Global Investment, FemHealth Ventures, Plaisance Capital, and Palo Santo. Earlier, in June 2023, MPM BioImpact acquired Reunion for $13.1 million, subsequently transitioning the company into a private entity.

The fresh funds will primarily support a Phase II clinical trial for RE104, aimed at postpartum depression patients. Recruitment for this trial is set to commence this quarter, with outcomes expected by the second quarter of 2025.

RE104 holds promise as a superior prodrug of 4-OH-DiPT, a synthetic psilocybin derivative known for its shorter duration of action. It targets the serotonin 2A receptor, a critical component in the antidepressant effects of psychedelic compounds. Uniquely, RE104 administration requires only half a day in a clinical setting, supervised by healthcare professionals, offering a time-efficient alternative to treatments like MDMA or traditional psilocybin.

Initial Phase I trials revealed that RE104 was well-tolerated and exhibited strong pharmacodynamic effects, with the therapeutic experience lasting approximately three to four hours. This contrasts with the lengthier six to eight-hour sessions typical of psilocybin-based treatments.

Greg Mayes, CEO of Reunion, described the financing as a pivotal milestone, expressing gratitude for the support from investors like MPM BioImpact and Novo Holdings. He emphasized that their backing underscores Reunion's potential to revolutionize mental health treatments for patients currently underserved by existing therapies.

Beyond postpartum depression, Reunion is exploring RE104's potential in other neuropsychiatric conditions such as adjustment disorder in cancer (ADC). This disorder reflects a maladaptive response to a cancer diagnosis, and current treatment paradigms fail to address it adequately.

Natalie Sacks, a venture partner at Novo Holdings U.S., highlighted the significant potential of RE104 to improve treatment outcomes for patients with limited options, not just in postpartum depression but across a spectrum of mental health disorders.

The psychedelic drug market has been increasingly attracting investment, especially after the 2019 approval of Janssen’s antidepressant nasal spray, Spravato. The latter, containing esketamine, chemically related to ketamine, has demonstrated significant market potential. According to Mordor Intelligence, the psychedelic market saw a tenfold increase in investment from 2019 to 2020.

The momentum in psychedelic research continues into 2024. For instance, the MAPS Public Benefit Corporation, now rebranded as Lykos Therapeutics, raised $100 million in a Series A round. The company has filed an NDA for its MDMA-assisted therapy targeting post-traumatic stress disorder (PTSD), among other developments.