BEDFORD, Mass.–Delix Therapeutics has secured $100 million in an oversubscribed Series C financing round to advance its experimental depression treatment Zalsupindole into Phase II clinical development and expand its pipeline of therapies targeting psychiatric, neurological and neurodegenerative diseases.
The financing was co-led by Johnson & Johnson Innovation – JJDC, Inc., the venture capital arm of Johnson & Johnson, and SV Health Investors’ Dementia Discovery Fund.
Existing investors RA Capital, UC Investments, Artis Ventures, OMX Ventures, Dolby Family Ventures and Bail Capital participated in the round. New investors included Adage Capital Management, Hamilton Square Partners Management, Vestal Point Capital and YK Bioventures.
Delix plans to use the funding to advance Zalsupindole, also known as DLX001, through Phase IIb proof-of-concept development for recurrent major depressive disorder (MDD). The company expects to initiate a placebo-controlled Phase II trial during the first half of 2027.
Additional funding will support the development of other drug candidates in the company’s neuroplastogen pipeline, including potential treatments for Alzheimer’s disease, Parkinson’s disease and other neurological conditions.
Delix specializes in developing neuroplastogens, experimental compounds designed to promote structural and functional changes in the brain by encouraging the formation and repair of connections between neurons.
The company’s approach draws on the neuroplasticity-related properties of psychedelics while seeking to eliminate the hallucinations, dissociation and other psychoactive effects associated with traditional psychedelic compounds.
“We are proud to welcome our new investors alongside the continued support of our existing shareholders as Delix enters its next stage of growth,” said Mark Rus, Chief Executive Officer of Delix Therapeutics. “The strength and validation of this syndicate reflects the growing conviction and data for neuroplastogens as an important new therapeutic class. This capital enables us to take Zalsupindole through Phase II Proof of Concept, advance a broader pipeline of differentiated medicines, and build Delix for the long term. We are particularly excited to partner with investor teammates who understand what it takes to translate breakthrough neuroscience into medicines that can reach patients at scale. Delix is more well positioned than ever to define the next chapter of true neuroplastogen medicine.”
Zalsupindole is an orally administered investigational drug inspired by 5-MeO-DMT, also known as mebufotenin, a psychedelic compound. Unlike traditional psychedelics, the drug has been engineered to promote neuroplasticity without producing hallucinatory, dissociative, sedative or other psychotomimetic effects.
The treatment is being developed as a potentially faster-acting alternative to conventional antidepressants, which often require several weeks to produce meaningful clinical benefits.
In a completed Phase Ib study involving adults with recurrent major depressive disorder, patients experienced an approximately 50% average reduction in depression severity scores after one week of treatment.
The improvements were measured using the Montgomery-Åsberg Depression Rating Scale (MADRS), a clinical assessment used to evaluate the severity of depressive symptoms.
Patients received Zalsupindole either daily or twice weekly, with improvements maintained through Day 36, approximately four weeks after the final dose.
Across more than 120 participants evaluated in clinical studies to date, Zalsupindole demonstrated what the company described as a favorable safety and tolerability profile.
Delix reported no hallucinatory, dissociative or other psychotomimetic effects based on clinician-administered assessments, patient-reported measures and objective evaluations. The company also reported no serious adverse events to date.
Preclinical studies have shown that Zalsupindole can increase dendritic spine density in neurons within the prefrontal cortex, a brain region involved in mood regulation, decision-making and cognitive function.
The findings suggest the compound may help restore connections between neurons, although larger clinical trials will be needed to establish whether these biological effects translate into sustained benefits for patients.
Beyond depression, Delix is developing additional neuroplastogen candidates targeting neurological and neurodegenerative conditions.
The company said its research has demonstrated encouraging preclinical findings in models of Alzheimer’s and Parkinson’s diseases, including evidence of increased synaptic density.
The Series C financing will allow Delix to advance additional drug candidates toward clinical testing and expand its neurodegeneration research programs.
As part of the financing, Christian Jung, PhD, a Partner at SV Health Investors, and a representative of Johnson & Johnson Innovation – JJDC have joined the Delix Board of Directors.
Jung brings experience in biotechnology investments and neurodegenerative disease research, while the JJDC representative has extensive experience supporting neuroscience-focused biotechnology companies.
“We are thrilled with the addition of these outstanding new Board members,” said Nick Haft, Partner at OMX Ventures, and Delix Co-Founder. “Their combined perspectives add important strategic depth as Delix enters its next stages of clinical and corporate development.”
Jung also highlighted the company’s approach to separating the potential therapeutic properties of psychedelic-inspired compounds from their hallucinogenic effects.
“We have been following the psychedelics field, and Delix is the first company we’ve seen to separate the neuroplastic benefits of psychedelics from their hallucinogenic effects,” commented Dr. Jung, Partner at SV Health Investors, DDF. “Alongside their encouraging clinical data, we are particularly excited by their ability to increase synaptic density across multiple preclinical models of Alzheimer’s and Parkinson’s disease, something of a holy grail for the field. I look forward to working with Mark, the Delix team and the other investors as they bring this pipeline forward.”
The planned Phase II trial will represent a significant milestone for Delix as it seeks to determine whether the improvements observed in earlier studies can be replicated in a larger, controlled patient population.
If successful, the program could support further development of Zalsupindole as a treatment for major depressive disorder and help establish the clinical potential of non-hallucinogenic neuroplastogens.
However, Zalsupindole remains investigational, and its safety and effectiveness must be established in subsequent clinical trials before it can be considered for regulatory approval.
