Medical device company Flow has announced that it has raised $1.5m towards its transcranial direct current stimulation (tDCS) device for the treatment of depression.

The funds will be used to support Flow’s European rollout, introduce the device to healthcare clinics and fund clinical studies. The investment round was led by Khosla Ventures.

People diagnosed with depression typically have lower neural activity in their left frontal lobe, part of the brain associated with cognitive skills and emotional expression. During tCDS a constant, low-level electric current is delivered to this part of the brain to stimulate and rebalance the area.

Flow’s headset is designed to be used in conjunction with a behavioural therapy app that educates users about depression and gives advice on how to reduce symptoms.

The company is currently in talks with the NHS to have the headset, which currently retails at £399, made available on prescription in the UK. One in four adults in the UK are estimated to be affected by a mental illness, the economic costs of which are estimated at £105bn annually in England alone.

Flow co-founder Daniel Mansson said: “We’re increasing treatment choice and empowering people to self-manage their symptoms at home with an effective, personalised and non-pharmacological alternative. This has the potential to improve the standard of care, and reduce global healthcare costs. The Khosla Ventures investment will support the next stage of our journey as we cement our position as European leaders of brain stimulation treatment for depression.”

The company has acquired a European Class IIa medical device CE mark, and launched commercially in the UK and Sweden in June 2019. It is now in talks with the US Food and Drug Administration to seek regulatory clearance in the US.

Khosla Ventures principal Alexander Morgan said: “We are very happy to be supporting Flow Neuroscience in this effort to bring a new medication-free treatment for depression into the market. The technology combines portable hardware and software, and we believe this offers an exciting and scalable solution for potentially hundreds of millions of people living with depression globally, empowering patients directly with new options for treatment.”