Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
This proof-of-concept study explores whether long-term home-based closed-loop auditory stimulation during sleep enhances slow-wave activity (SWA) and yields preliminary efficacy signals in patients with amnestic mild cognitive impairment due to Alzheimer's disease (MCI-AD), confirmed by cerebrospinal fluid (CSF) biomarkers or positron emission tomography (PET).
The intervention is self-administered at participants' homes over an initial treatment period of 3 months, followed by a 1-month off-treatment (washout) period. Participants may then enter an optional extension phase consisting of 3 additional months of treatment followed by a second 1-month washout period, for a total study duration of up to 8 months.
Participants who complete the Nana-Lab Study (NCT07402590) may be invited to provide informed consent for screening and potential enrollment in this study. All enrolled participants receive nightly active treatment during intervention periods. This study does not include randomization or a sham control group.
Alzheimer's disease (AD) is characterized by progressive cognitive decline and is preceded by a prodromal stage known as amnestic mild cognitive impairment due to AD (MCI-AD), in which early neurophysiological alterations are detectable. Among these, disruptions in sleep architecture-particularly reductions in slow-wave activity (SWA; ~0.5-4 Hz) and sleep spindle activity (~11-16 Hz)-have been associated with impaired memory consolidation and the progression of AD-related pathophysiological processes.
Closed-loop auditory stimulation during sleep (CLAS) is a non-invasive neuromodulation approach that delivers precisely timed auditory stimuli phase-locked to endogenous slow oscillations, with the aim of enhancing slow-wave activity and associated thalamocortical spindle dynamics. This targeted entrainment of sleep oscillations may improve sleep-dependent neural processes and represents a potential therapeutic strategy in the early stages of AD.
The present study is an open-label, single-arm investigation designed to evaluate the effects of home-based CLAS in patients with biomarker-confirmed amnestic mild cognitive impairment due to Alzheimer's disease (MCI-AD). The intervention is self-administered in the participants' home environment. All participants complete an initial treatment period of 3 months followed by a one-month off-treatment (washout) period to assess persistence of effects. Participants who elect to continue may then enter an optional extension phase consisting of 3 additional months of treatment, followed by a second one-month off-treatment period. The total study duration is approximately 4 months for participants completing the initial phase only, or approximately 8 months for those completing the extension phase.
The primary objective is to assess target engagement, defined as the modulation of NREM sleep electrophysiological activity, with particular focus on slow-wave sleep. More precisely, sustained increases in slow-wave activity across the intervention period will be quantified using the study EEG device during intervention nights.
Secondary objectives include evaluation of adherence to the intervention, usability of the device in the home environment, and safety and tolerability. Exploratory objectives include evaluation of the intervention's effects on clinical, functional, cognitive, and sleep-related outcomes, as well as blood-based biomarkers. Clinical, functional, and cognitive variables will be assessed at three time points: before intervention (baseline, Month 0), at the end of the initial treatment period (Month 3), and, for participants entering the extension phase, at the end of the extended treatment period (Month 7).
Blood biomarkers will be obtained at the following time points: baseline (Month 0), end of the initial treatment period (Month 3), and end of the first washout period (Month 4). Participants entering the extension phase will have two additional blood draws: at the end of the extended treatment period (Month 7) and at the end of the second washout period (Month 8). Sleep metrics, derived from EEG recordings or subjective responses to digitized questionnaires, will be acquired daily using the home-based study device.
This study does not include randomization or a sham control group; all participants receive active treatment during intervention periods. The results are expected to provide evidence on neurophysiological target engagement, feasibility, safety, and the clinical and biological effects of home-based CLAS as a therapeutic strategy in early-stage AD.
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Auditory Stimulation Intervention Group | Experimental | Participants receive closed-loop auditory stimulation during sleep at home for an initial treatment period of 3 months, followed by a 1-month off-treatment (washout) period. Participants may then enter an optional extension phase consisting of 3 additional months of treatment followed by a second 1-month washout period. |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Closed-Loop Auditory Stimulation | Device | The system delivers brief auditory stimuli (pink noise bursts) that are time-locked to the up-phase of endogenous slow oscillations during non-rapid eye movement (NREM) sleep, as detected in real time using electroencephalography (EEG). Stimulation is withheld in approximately half of detected slow oscillations (Sham) to serve as a within-session control condition for the acute effects of stimulation. The other half of the slow oscillations are stimulated at a volume between 30-60 dB (Stim), which is personalized to the patient and adapts during the night to improve response while reducing awakenings. The objective of the stimulation is to enhance slow-wave activity (SWA) during deep sleep through phase-specific entrainment of endogenous slow-wave activity. The intervention is self-administered using a portable system adapted for use in patients with MCI. Participants are instructed to use the device for as many nights as possible throughout the study period. |
| Measure | Description | Time Frame |
|---|---|---|
| Target Engagement: Sustained Increase in Slow-Wave Activity During N2-N3 Sleep | Within-subject difference in mean slow-wave activity during N2-N3 sleep between stimulation and sham conditions, computed nightly and aggregated across the intervention period. The sustained effect will be evaluated as the consistency of the stimulation-induced increase in slow-wave activity across nights throughout the intervention period. | Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Measure | Description | Time Frame |
|---|---|---|
| Sustained Increase in Spindle Activity During N2-N3 Sleep | Within-subject difference in spindle activity (spindle occurrence during N2-N3 sleep) between stimulation and sham conditions, computed nightly and aggregated across the intervention period. The sustained effect will be evaluated as the consistency of the stimulation-induced increase in spindle activity across nights throughout the intervention period. |
| Measure | Description | Time Frame |
|---|---|---|
| Cognitive Performance - Alzheimer's Disease Assessment Scale-Cognitive Subscale, 11-item version (ADAS-Cog 11) | Change from baseline in global cognitive performance, as measured by the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) 11-item version (ADAS-Cog 11). Scores range from 0 to 70, with higher scores indicating poorer cognitive performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
Inclusion criteria:
Exclusion criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| Bit&Brain Technologies SL | Zaragoza | Zaragoza | 50006 | Spain |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
|
|
| Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Adherence to the Intervention | Average number of intervention nights attempted per week. An intervention night is defined as a night during which the participant initiates use of the technology. Adherence will also be summarized as the proportion of participants achieving an average of at least 4 nights per week. | Computed as a summary measure over each participant's full intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Usability of the Closed-Loop Auditory Stimulation System | Percentage of successful sessions among all attempted sessions. A successful session is defined as one in which the participant correctly sets up the device, the system initializes, and usable physiological data are recorded. Sessions may be unsuccessful due to patient-side factors (e.g., electrode placement errors), device-side factors (e.g., technical malfunction), or both. | Computed as a summary measure over each participant's full intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Safety and Tolerability | Incidence, severity, and relatedness of adverse events associated with the intervention, including sleep disturbance, discomfort related to auditory stimulation, and any device-related adverse effects. Safety will be assessed continuously and summarized at interim and final analyses. | Continuously monitored from enrollment through the end of participation, with summary analyses at 3 months and, for participants entering the extension phase, at 7 months. |
| Functional Ability - Alzheimer's Disease Cooperative Study-Activities of Daily Living scale for Mild Cognitive Impairment (ADCS-ADL-MCI) | Change from baseline in activities of daily living measured using the Alzheimer's Disease Cooperative Study-Activities of Daily Living scale for Mild Cognitive Impairment (ADCS-ADL-MCI). Scores range from 0 to 69; higher scores indicate better functional ability. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Global Cognition - MoCA | Change from baseline in global cognitive function, as measured by the Montreal Cognitive Assessment (MoCA). Scores range from 0 to 30, with higher scores indicating better cognitive performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Episodic Memory - Rey Auditory Verbal Learning Test (RAVLT) Total Learning Score (Trials 1-5) | Change from baseline in episodic memory performance, assessed using the Rey Auditory Verbal Learning Test (RAVLT) total learning score (Trials 1-5). Scores range from 0 to 75, with higher scores indicating better episodic memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Immediate Memory - Wechsler Memory Scale-Fourth Edition (WMS-IV) Logical Memory I | Change from baseline in immediate memory performance, assessed using the Wechsler Memory Scale-Fourth Edition (WMS-IV) Logical Memory I subtest. Scores range from 0 to 53, with higher scores indicate better immediate memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Episodic Memory - Wechsler Memory Scale-Fourth Edition (WMS-IV) Logical Memory II | Change from baseline in episodic memory performance, assessed using the Wechsler Memory Scale-Fourth Edition (WMS-IV) Logical Memory II subtest. Scores range from 0 to 39, with higher scores indicate better episodic memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7) |
| Immediate Memory - Wechsler Memory Scale-Fourth Edition (WMS-IV) Verbal Paired Associates I | Change from baseline in immediate memory performance, assessed using the Wechsler Memory Scale-Fourth Edition (WMS-IV) Verbal Paired Associates I subtest. Scores range from 0 to 40, with higher scores indicate better immediate memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7) |
| Episodic Memory - Wechsler Memory Scale-Fourth Edition (WMS-IV) Verbal Paired Associates II | Change from baseline in episodic memory performance, assessed using the Wechsler Memory Scale-Fourth Edition (WMS-IV) Verbal Paired Associates II subtest. Scores range from 0 to 10, with higher scores indicate better episodic memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Visual Reproduction - Wechsler Memory Scale-Fourth Edition (WMS-IV) Visual Reproduction I | Change from baseline in visual memory performance, assessed using the Wechsler Memory Scale-Fourth Edition (WMS-IV) Visual Reproduction I subtest. Scores range from 0 to 43, with higher scores indicating better visual memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7) |
| Visual Reproduction - Wechsler Memory Scale-Fourth Edition (WMS-IV) Visual Reproduction II | Change from baseline in visual memory performance, assessed using the Wechsler Memory Scale-Fourth Edition (WMS-IV) Visual Reproduction II subtest. Scores range from 0 to 43, with higher scores indicating better visual memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7) |
| Working Memory - Wechsler Memory Scale-Fourth Edition (WMS-IV) Symbol Span | Change from baseline in working memory performance, assessed using the Wechsler Memory Scale-Fourth Edition (WMS-IV) Symbol Span subtest. Scores range from 0 to 50, with higher scores indicating better working memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7) |
| Working Memory - Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Digit Span | Change from baseline in working memory, assessed using the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Digit Span subtest. Scores range from 0 to 48, with higher scores indicating better working memory performance | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Working Memory - Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Arithmetic | Change from baseline in working memory, assessed using the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Arithmetic subtest. Scores range from 0 to 22, with higher scores indicating better working memory performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7) |
| Processing Speed - Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Symbol Search | Change from baseline in processing speed, assessed using the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Symbol Search subtest. Scores range from 0 to 60, with higher scores indicating better processing speed performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7) |
| Processing Speed - Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Coding | Change from baseline in processing speed, assessed using the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Coding subtest. Scores range from 0 to 135, with higher scores indicating better processing speed performance. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Anxiety Symptoms - Goldberg Anxiety Scale | Change from baseline in anxiety symptoms, measured using the Goldberg Anxiety Scale. Scores range from 0 to 9, with higher scores indicating worse anxiety symptoms. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Depressive Symptoms - PHQ-8 | Change from baseline in depressive symptoms, measured using the Patient Health Questionnaire-8 (PHQ-8). Scores range from 0 to 24, with higher scores indicating greater symptom severity. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Patient Self-Reported Experience (Daily) | Daily subjective cognitive and affective experience assessed using Temporal Experience Tracing (TET). TET is a visual-analog method in which participants retrospectively graph the intensity of an experience along several phenomenological dimensions over time, producing daily compositional profiles of cognitive and emotional states. | Assessed daily on intervention days, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Sleep macrostructure - Sleep duration | Change from baseline in sleep duration, estimated from EEG recordings. The duration of sleep will be quantified as the Time In Bed (TIB), defined as the full length from the start to the end of the recording; Sleep Period Time (SPT), from the first to the last epoch of sleep; and Total Sleep Time (TST), the cumulative duration of all sleep stages (N1, N2, N3, and REM). Sleep duration will be quantified in minutes. Sleep macrostructure will be measured using the scoring manual of the American Academy of Sleep Medicine (AASM; Iber et al., 2007) as the established standard, obtaining the sleep stage for each 30-sec epoch of the recording. | Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Sleep macrostructure - Percentage of Time per Sleep Stage | Change from baseline in the distribution of sleep stages (%): N1, N2, N3, REM, Wake, estimated from EEG recordings. The time spent in each sleep stage will be reported with respect to sleep time, in percentage. Sleep macrostructure will be measured using the scoring manual of the American Academy of Sleep Medicine (AASM; Iber et al., 2007) as the established standard, obtaining the sleep stage for each 30-sec epoch of the recording. | Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Sleep macrostructure - Efficiency of sleep | Change from baseline in efficiency of sleep, estimated from EEG recordings. Sleep Efficiency (SE) constitutes the ratio between total sleep time and time in bed, whereas Sleep Maintenance Efficiency (SME) is the ratio between total sleep time and sleep period time, representing the proportion of time spent alseep. Sleep macrostructure will be measured using the scoring manual of the American Academy of Sleep Medicine (AASM; Iber et al., 2007) as the established standard, obtaining the sleep stage for each 30-sec epoch of the recording. | Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Sleep macrostructure - Wake after sleep onset | Change from baseline in time spent awake after the onset of sleep, estimated from EEG recordings. Wake After Sleep Onset (WASO) is the accumulated wake time (in minutes) within sleep period time. Sleep macrostructure will be measured using the scoring manual of the American Academy of Sleep Medicine (AASM; Iber et al., 2007) as the established standard, obtaining the sleep stage for each 30-sec epoch of the recording. | Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Sleep macrostructure - Sleep onset latency | Change from baseline in sleep onset latency, estimated from EEG recordings. Sleep Onset Latency (SOL) is the time in minutes from the start of the recording to the first epoch of sleep. This metric can also be computed for each individual sleep stage (N1, N2, N3, and REM), measured from the start of the recording to the first occurrence of that stage. Sleep macrostructure will be measured using the scoring manual of the American Academy of Sleep Medicine (AASM; Iber et al., 2007) as the established standard, obtaining the sleep stage for each 30-sec epoch of the recording. | Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Sleep macrostructure - Sleep fragmentation | Change from baseline in sleep fragmentation, estimated from EEG recordings. Sleep fragmentation is measured as the number of sleep stage changes (i.e., the number of transitions between diferent stages) througout the night. The number of transitions from any sleep stage (N1, N2, N3, REM) to wake constitute the number of awakenings. Sleep macrostructure will be measured using the scoring manual of the American Academy of Sleep Medicine (AASM; Iber et al., 2007) as the established standard, obtaining the sleep stage for each 30-sec epoch of the recording. | Assessed at each intervention night, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Subjective Sleep Quality - PSQI | Change from baseline in self-reported sleep quality, measured using the Pittsburgh Sleep Quality Index (PSQI). Global scores range from 0 to 21, with higher scores indicating poorer sleep quality. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Subjective Sleep Quality - ISI | Change from baseline in insomnia severity, measured using the Insomnia Severity Index (ISI). Scores range from 0 to 28, with higher scores indicating more severe insomnia. | Assessments at baseline (Month 0), end of initial treatment (Month 3), and end of extension treatment (Month 7). |
| Daytime Sleepiness | Daily self-reported daytime sleepiness assessed using the Stanford Sleepiness Scale (SSS). Scores range from 1 to 7, with higher scores indicating greater sleepiness. | Assessed daily on intervention days, from baseline through the end of the intervention period (3 months, or up to 7 months for participants entering the extension phase). |
| Plasma Amyloid Pathology - Amyloid-Beta 42/40 Ratio | Change from baseline in plasma amyloid-beta 42/40 ratio, assessed to characterize within-subject temporal dynamics across intervention and washout periods. Higher values indicate a higher amyloid-beta 42/40 ratio. | Assessments at baseline (Month 0), end of initial treatment (Month 3), end of first washout (Month 4), end of extension treatment (Month 7), and end of second washout (Month 8). |
| Plasma Phosphorylated Tau 217 (p-tau217) | Percent change from baseline in plasma phosphorylated tau 217 (p-tau217). Values will be reported as percent change (%), with negative values representing decreases and positive values representing increases relative to baseline. | Assessments at baseline (Month 0), end of initial treatment (Month 3), end of first washout (Month 4), end of extension treatment (Month 7), and end of second washout (Month 8) |
| Plasma Neurodegeneration Biomarker - Glial Fibrillary Acidic Protein (GFAP) | Percent change from baseline in plasma glial fibrillary acidic protein (GFAP), assessed to characterize within-subject temporal dynamics across intervention and washout periods. Values will be reported as percent change (%); negative values indicate a decrease and positive values indicate an increase in circulating GFAP levels relative to baseline. | Assessments at baseline (Month 0), end of initial treatment (Month 3), end of first washout (Month 4), end of extension treatment (Month 7), and end of second washout (Month 8). |
| Plasma Neurodegeneration Biomarker - Neurofilament Light Chain (NfL) | Percent change from baseline in plasma neurofilament light chain (NfL), assessed to characterize within-subject temporal dynamics across intervention and washout periods. Values will be reported as percent change (%); negative values indicate a decrease and positive values indicate an increase in circulating NfL levels relative to baseline. | Assessments at baseline (Month 0), end of initial treatment (Month 3), end of first washout (Month 4), end of extension treatment (Month 7), and end of second washout (Month 8). |
| Plasma Inflammatory Biomarker - Interleukin-6 (IL-6) | Percent change from baseline in plasma interleukin-6 (IL-6), assessed to characterize within-subject temporal dynamics across intervention and washout periods. Values will be reported as percent change (%); negative values indicate a decrease and positive values indicate an increase in circulating IL-6 levels relative to baseline. | Assessments at baseline (Month 0), end of initial treatment (Month 3), end of first washout (Month 4), end of extension treatment (Month 7), and end of second washout (Month 8) |
| Plasma Inflammatory Biomarker - Interleukin-10 (IL-10) | Percent change from baseline in plasma interleukin-10 (IL-10), assessed to characterize within-subject temporal dynamics across intervention and washout periods. Values will be reported as percent change (%); negative values indicate a decrease and positive values indicate an increase in circulating IL-10 levels relative to baseline. | Assessments at baseline (Month 0), end of initial treatment (Month 3), end of first washout (Month 4), end of extension treatment (Month 7), and end of second washout (Month 8). |
| Plasma Inflammatory Biomarker - Tumor Necrosis Factor Alpha (TNF-alpha) | Percent change from baseline in plasma tumor necrosis factor alpha (TNF-alpha), assessed to characterize within-subject temporal dynamics across intervention and washout periods. Values will be reported as percent change (%); negative values indicate a decrease and positive values indicate an increase in circulating TNF-alpha levels relative to baseline. | Assessments at baseline (Month 0), end of initial treatment (Month 3), end of first washout (Month 4), end of extension treatment (Month 7), and end of second washout (Month 8).] |
| ID | Term |
|---|---|
| D060825 | Cognitive Dysfunction |
| ID | Term |
|---|---|
| D003072 | Cognition Disorders |
| D019965 | Neurocognitive Disorders |
| D001523 | Mental Disorders |
Not provided
Not provided