HALO Clarity™ Cranial Alternating Current Stimulation Therapy for Adults With Moderate-to-Severe Insomnia

The HALO Clarity™ Transcranial Alternating Current Stimulation Therapy for Adults with Moderate-to-Severe Insomnia trial is a prospective, decentralized, individually-randomized, triple-blind, sham-controlled superiority study evaluating the safety and efficacy of the HALO Clarity™ device in adults with moderate-to-severe insomnia.

The HALO Clarity™ device is a non-invasive cranial electrotherapy stimulator designed for at-home use. It delivers a proprietary alternating current waveform with an amplitude of 15 mA RMS, modulated at 77.5 Hz and superimposed on a 100 kHz carrier frequency. The device consists of a lightweight wearable headset with three dry electrodes (one forehead and two mastoid) connected via Bluetooth to a dedicated mobile application. The application guides users through treatment sessions, monitors electrode contact quality, displays remaining treatment time, and automatically logs usage data.

This trial employs a fully decentralized (remote/virtual) design to evaluate the device under conditions consistent with its intended real-world use. All study activities-including informed consent, pre-screening, screening, clinical evaluation, randomization, device shipment to the participant's home, treatment, and follow-up assessments-are conducted remotely without requiring in-person clinic visits. This approach reduces participant burden, expands geographic access, and maintains high data quality through centralized electronic data capture systems and structured remote clinician oversight.

The study uses a 1:1 randomized, triple-blind, sham-controlled design. Participants, clinical site personnel (including investigators), and study researchers responsible for outcome assessment remain blinded to treatment allocation throughout the trial. The sham device is physically identical to the active device in appearance, weight, electrode placement, vibration feedback, and mobile application interface. However, the sham device delivers a non-therapeutic modulation scheme consisting of brief ramp-up and ramp-down pulses designed to provide a similar initial sensory experience while lacking the sustained neuromodulatory effect of the active 77.5 Hz waveform. This sham design supports maintenance of participant blinding while allowing estimation of the specific treatment effect attributable to the active stimulation. Eligible participants are adults aged 22 to 65 years with moderate-to-severe insomnia, defined as an Insomnia Severity Index (ISI) total score of 15 or greater.

The treatment period consists of one 40-minute session per day, five days per week, for four consecutive weeks (maximum of 20 sessions). Sessions may be performed at any time of day except within three hours of the participant's intended bedtime. Treatment compliance is automatically recorded via the device and application. After completing the four-week treatment period, all participants enter a four-week post-treatment follow-up period to assess durability of effect.

The primary endpoint is the mean total ISI score at four weeks after treatment initiation, comparing participants assigned to the active device versus those assigned to the sham device. Key secondary endpoints include ISI score at eight weeks (durability), Pittsburgh Sleep Quality Index (PSQI) scores at four and eight weeks, and Short Form-36 (SF-36) health-related quality of life scores at four and eight weeks. Exploratory endpoints include changes in PHQ-9 depression scores, GAD-7 anxiety scores, and the proportion of participants achieving a clinically meaningful improvement (reduction of ≥6 points) on the By evaluating the HALO Clarity™ device in a rigorous, sham-controlled, decentralized trial, this study aims to generate high-quality evidence regarding its safety and efficacy as a non-pharmacological treatment for moderate-to-severe insomnia. If successful, the device could offer a convenient, home-based treatment option that addresses unmet needs in the current insomnia treatment landscape.

Inclusion criteria

Participants must meet all of the following criteria to be eligible for the study:

• Provide written informed consent prior to any study-related procedures.
• Age between 22 and 65 years, inclusive.
• Total score on the Insomnia Severity Index (ISI) of ≥15 at screening, indicating moderate-to-severe insomnia.
• Participant-reported diagnosis of insomnia, confirmed by a licensed clinician during the remote clinical evaluation call.
• Willingness to be randomized to either the active or sham device arm.
• Agreement not to use any sleep tracking devices or applications (e.g., smartwatches, sleep apps) during the study.
• Ability to read and write English at an 8th-grade level or higher.
• Ability to receive packages at home via standard delivery services (United States Postal Service, FedEx, or UPS) in all U.S. states except Alaska and Hawaii.
• Willing and able to use a personal internet-capable mobile device throughout the study for completing questionnaires, using the HALO Clarity™ App, and receiving study-related text messages.
• Owns and is willing to communicate using a personal, verifiable email address.
• Able and willing to commit to one 40-minute treatment session using the HALO Clarity™ device, 5 days per week for 4 weeks (up to 20 sessions total).
• If currently using sleep medication, the regimen must have been stable for at least the past 3 months, with willingness to maintain the same medication and dosage throughout the study (no new sleep medications may be started during the trial).

Exclusion criteria

Participants who meet any of the following criteria will be excluded from the study:

• Presence of a current medical condition that, in the opinion of the Investigator or delegate, could impair reliable participation in the study or require the use of prohibited medications.
• Use of any form of electronic brain stimulation or neuromodulation within the past 1 year (including cranial electrotherapy stimulation [CES], transcranial magnetic stimulation [TMS], electroconvulsive therapy [ECT], or deep brain stimulation).
• Institutionalization for a mental health condition within 1 year prior to study entry.
• Current or history of alcohol or drug abuse or dependence within the past 5 years.
• Under medical supervision for a serious medical condition (including, but not limited to, intracranial tumors or aneurysm).
• Suspected or known history of heart disease.
• Implanted electronic device (e.g., pacemaker, defibrillator, deep brain stimulator, or cochlear implant).
• History of seizures or epilepsy.
• History or current diagnosis of a chronic pain condition and/or use of opioids for any reason within the past 3 months.
• Use of recreational drugs, hypnotics, anabolic steroids, or marijuana products within the past 30 days, or planned use during the study (stable use of CBD is permitted).
• Females who are currently pregnant or planning to become pregnant during study participation.
• Current participation in another investigational study, or participation in an investigational study within the past 30 days.
• Any other condition or circumstance that, in the opinion of the Investigator, would make the participant unsuitable for the study.