Motif Neurotech has announced an oversubscribed Series A financing round, raising $18.75m to further the development of its implantable device aimed at treatment-resistant depression (TRD).

The funding round was led by Arboretum Ventures and saw participation from several new investors including KdT Ventures, Dolby Family Ventures, Satori Neuro, re.Mind Capital and individual investor Max Hodak.

It also involved participation from existing investors including Divergent Capital, PsyMed Ventures, TMC Innovation, Empath Ventures and Capital Factory.

Motif plans to use the proceeds from the Series A financing for the advancement of its lead product, the DOT microstimulator.

This miniature pacemaker is designed to stimulate the brain precisely, restoring healthy circuit activity to treat mental health disorders, with an initial focus on TRD.

TRD is a form of major depressive disorder that does not respond to traditional anti-depressant medications.

Motif Neurotech CEO and founder Jacob Robinson said: “Minimally-invasive bioelectronics are the future of mental health treatment. 30% of patients with depression don’t respond to two or more medications, and there is a significant need for additional treatment options that are effective and easily accessible.

“The DOT microstimulator is a wireless, battery-free device designed to be implanted in a 20-minute outpatient procedure with the capability for at-home therapy. This round of financing will allow us to bring this technology into a clinical study for patients with TRD.”

With the closing of the financing round, Satori Neuro chief investment officer Amy Kruse and Arboretum Ventures managing partner Tom Shehab will join Motif Neurotech's board of directors.

They will serve alongside Anthony Arnold and Jacob Robinson.

Shehab said: “We believe Motif’s device will greatly improve the quality of life for patients who have been diagnosed with difficult-to-treat mental health disorders, including TRD.”