HALO Clarity™ Cranial Alternating Current Stimulation Therapy for Adults With Moderate-to-Severe Insomnia: A Prospective, Individually-Randomized, Triple-Blind, Sham-Controlled, Decentralized, Superiority Trial

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.