📗 Cite This Artifact
NAB-IT: Nabilone for Agitation in Alzheimer's Disease
Nabilone for Agitation Blinded Intervention Trial (NAB-IT)
Overview
Nabilone for Agitation Blinded Intervention Trial (NAB-IT)
Overview
Nabilone for Agitation Blinded Intervention Trial (NAB-IT) is a Phase 3 randomized, double-blind, placebo-controlled clinical trial evaluating the efficacy and safety of nabilone (a synthetic cannabinoid) for the treatment of agitation in patients with Alzheimer's disease (AD). The trial is conducted by Sunnybrook Health Sciences Centre in Toronto, Canada.
Trial Information
| Field | Value |
|-------|-------|
| NCT Number | [NCT04516057](https://clinicaltrials.gov/study/NCT04516057) |
| Phase | Phase 3 |
| Status | Recruiting |
| Sponsor | Sunnybrook Health Sciences Centre |
| Collaborator | Alzheimer's Drug Discovery Foundation |
| Start Date | February 1, 2021 |
| Primary Completion | April 2027 (Estimated) |
| Enrollment | 112 participants (Estimated) |
Study Design
Allocation & Masking
- Design: Randomized, Parallel Assignment, Quadruple Masking
- Participants, Care Providers, Investigators, and Outcome Assessors are all blinded
Arms
Experimental Arm: Nabilone
- Participants receive nabilone for 8 weeks
- Titrated up to a maximum dose of 2 mg/day
- Followed for 8 weeks post-treatment
Placebo Comparator Arm
- Participants receive placebo capsules for 8 weeks
- Followed for 8 weeks post-treatment
Study Population
Inclusion Criteria
Exclusion Criteria
Outcome Measures
Primary Outcome
| Measure | Description | Timeframe |
|---------|-------------|-----------|
| Cohen-Mansfield Agitation Inventory (CMAI) | 29-point scale measuring verbal and physical agitation. Scores range 29-203, higher = worse | Baseline to 8 weeks |
Secondary Outcomes
| Measure | Description |
|---------|-------------|
| Neuropsychiatric Inventory - Nursing Home (NPI-NH) | Assesses behavior disturbances (apathy, agitation, delusions, hallucinations, depression, etc.). Scores 0-144 |
| Standardized Mini-Mental State Examination (sMMSE) | Global cognition assessment. Scores 0-30, lower = worse |
| Mini Nutritional Assessment - Short Form (MNA-SF) | Nutritional status. Scores 0-14 |
| Pain Assessment Checklist (PACSLAC-II) | Pain assessment for seniors. Scores 0-31 |
| ADCS-CGIS/C | Clinical Global Impression of Severity/Change |
Other Outcomes
| Measure | Description |
|---------|-------------|
| UKU Side-Effect Rating Scale | Sedation assessment using Sleepiness/Sedation subscale (scores 0-3) |
Rationale
Agitation is highly prevalent in Alzheimer's disease and is one of the most distressing and challenging-to-treat neuropsychiatric symptoms. It is associated with:
- Faster progression to institutionalization
- Increased caregiver burden
- Poorer quality of life
- Increased risk of death
Current pharmacological options show only modest efficacy and elevated risks of adverse events. This makes identifying safer and more effective treatments a clinical and research priority.
Preliminary Evidence
The research group completed a 6-week double-blind placebo-controlled randomized cross-over pilot trial in 38 patients with moderate-to-severe AD, providing the first preliminary evidence for nabilone's efficacy. They found that nabilone significantly improved agitation, overall neuropsychiatric symptoms, and caregiver distress[@herrmann2019].
Mechanism of Action {#mechanism}
Nabilone is a synthetic cannabinoid that targets the endocannabinoid system[@wu2022]:
CB1 Receptor
- Central cannabinoid receptor (CB1R) is widely distributed in the brain
- Highest density in [hippocampus](/brain-regions/hippocampus), basal ganglia, cerebellum, [prefrontal cortex](/brain-regions/prefrontal-cortex)
- Modulates neurotransmitter release (glutamate, GABA, dopamine)
- Involved in memory, emotional processing, and motor control
CB2 Receptor
- Peripheral receptor (CB2R) primarily in immune cells
- Expressed in microglia in the brain
- Modulates neuroinflammation
- Anti-inflammatory effects in neurodegenerative contexts
Therapeutic Mechanisms in AD
- CB1R activation in frontal-limbic circuits
- Reduced anxiety and agitation signaling
- Calming effect without sedation
- CB2R-mediated microglial modulation
- Reduced pro-inflammatory cytokine release
- Antioxidant properties
- CB1R involvement in circadian rhythms
- Improved nighttime sleep
- Reduced daytime agitation
Comparison to Other Approaches
| Treatment | Mechanism | Efficacy | Safety |
|-----------|-----------|----------|--------|
| Nabilone | CB1/CB2 agonist | Moderate | Requires monitoring |
| Risperidone | D2 antagonist | Moderate | Extrapyramidal effects |
| Quetiapine | Multi-receptor | Low-moderate | Sedation, metabolic |
| trazodone | 5-HT antagonist | Low | Sedation |
Intervention Details
Nabilone (brand name: Cesamet) is a synthetic cannabinoid that is Health Canada-approved to treat chemotherapy-induced nausea and vomiting. It is a cannabinoid receptor agonist that acts on the CB1 and CB2 receptors.
Pharmacology:
- Full agonist at CB1R and CB2R
- Long half-life (35-50 hours)
- Oral administration
- Metabolized in liver (CYP3A4)
- Starting dose: 0.5 mg, titrated to 2 mg
Clinical Evidence to Date
Pilot Study Results (Herrmann et al., 2019)
The foundational pilot study demonstrated:
- Significant reduction in CMAI scores (p=0.03)
- Improved NPI-NH total scores
- Reduced caregiver distress
- Well-tolerated with mild side effects
Safety Profile
Common Adverse Effects:
- Sedation (manageable with dose adjustment)
- Dizziness
- Dry mouth
- Weight gain (monitor)
- Potential for cognitive effects at high doses
- Drug interactions (CYP3A4 inhibitors)
- Psychiatric considerations (history-dependent)
Future Directions
Larger Trials
- Multi-site Phase 3 implementation
- Long-term safety extension
- Combination with non-pharmacological approaches
Biomarker Integration
- CSF cannabinoid levels
- Neuroinflammatory markers
- Neuroimaging correlates
Agitation in Alzheimer's Disease
Definition and Prevalence
Agitation is one of the most common and distressing neuropsychiatric symptoms in Alzheimer's disease, affecting 40-60% of patients across disease stages. It encompasses a heterogeneous group of behaviors including:
| Category | Examples |
|----------|----------|
| Physical aggression | Hitting, kicking, biting, pushing |
| Verbal aggression | Yelling, screaming, threatening |
| Non-aggressive agitation | Pacing, fidgeting, repetitive behaviors |
| Disinhibition | Inappropriate sexual behavior, screaming |
Impact on Patients and Caregivers
Agitation significantly impacts quality of life:
| Impact Area | Consequence |
|-------------|-------------|
| Patient wellbeing | Increased distress, reduced quality of life |
| Caregiver burden | Physical and emotional exhaustion |
| Institutionalization | Primary driver of nursing home placement |
| Healthcare costs | Increased hospitalizations, medication use |
| Mortality | Associated with increased mortality risk |
Current Treatment Options
| Treatment | Efficacy | Limitations |
|-----------|----------|-------------|
| Non-pharmacological | Moderate | Requires training, time-intensive |
| Antipsychotics | Modest | Black box warning, mortality risk |
| SSRIs | Variable | Slow onset, side effects |
| Benzodiazepines | Limited | Sedation, fall risk, dependence |
| Cannabinoids | Under investigation | Regulatory issues, safety concerns |
Pathophysiology of Agitation in AD
The biological basis of agitation in AD involves multiple systems:
Neuroanatomical Changes
- Prefrontal cortex dysfunction
- Anterior cingulate hyperactivity
- Amygdala reactivity
- White matter disconnection
Neurochemical alterations
- Serotoninergic dysfunction
- Dopaminergic changes
- Noradrenergic dysregulation
- GABAergic system involvement
Inflammatory mechanisms
- Elevated cytokines
- Microglial activation
- Neuroinflammation contribution
Endocannabinoid System
Overview
The endocannabinoid system (ECS) is a complex neuromodulatory system involved in various physiological processes. It consists of:
| Component | Function |
|-----------|----------|
| Endocannabinoids | Anandamide, 2-AG |
| Cannabinoid receptors | CB1, CB2 |
| Metabolic enzymes | FAAH, MAGL |
| Transport proteins | FABP, ABC |
CB1 Receptor
The CB1 receptor is one of the most abundant G-protein-coupled receptors in the brain[@manuel2023]:
| Region | Density | Function |
|--------|---------|----------|
| Hippocampus | High | Memory, learning |
| Cerebellum | High | Motor coordination |
| Basal ganglia | High | Movement control |
| Prefrontal cortex | Moderate | Executive function |
| Amygdala | Moderate | Emotion regulation |
CB2 Receptor
CB2 receptors are primarily found in peripheral immune cells but are also expressed in brain microglia[@bachs2020]:
| Cell Type | CB2 Expression | Function |
|-----------|-----------------|----------|
| Microglia | Induced | Neuroinflammation modulation |
| Astrocytes | Low-Moderate | Glial function |
| Neurons | Very low | Unknown |
Endocannabinoid Functions
| Function | Mechanism |
|----------|-----------|
| Memory | Synaptic plasticity modulation |
| Emotion | Amygdala function |
| Pain | Nociceptive processing |
| Appetite | Hypothalamic regulation |
| Sleep | Sleep-wake cycle |
The ECS in Alzheimer's Disease
Alterations in the ECS have been documented in AD:
| Finding | Implication |
|---------|-------------|
| Reduced CB1 density | Memory dysfunction |
| Elevated 2-AG | Inflammatory response |
| CB2 upregulation | Immune modulation |
| FAAH alterations | Endocannabinoid tone |
Cannabinoid Pharmacology
Nabilone Properties
Nabilone (Cesamet) is a synthetic cannabinoid with specific pharmacology:
| Property | Value |
|----------|-------|
| CB1 affinity | High agonist |
| CB2 affinity | High agonist |
| Half-life | 35-50 hours |
| Onset | 1-2 hours |
| Peak | 2-4 hours |
| Metabolism | CYP3A4, CYP2C19 |
| Excretion | Feces (65%), urine (20%) |
Dose and Administration
| Parameter | Recommendation |
|-----------|----------------|
| Starting dose | 0.5 mg |
| Titration | 0.5 mg increments |
| Maximum | 2 mg/day |
| Frequency | BID or daily |
| Administration | Oral, with/without food |
Drug Interactions
| Interaction | Effect | Management |
|-------------|--------|------------|
| CYP3A4 inhibitors | Increased levels | Dose reduction |
| CYP3A4 inducers | Decreased levels | Avoid |
| CNS depressants | Additive sedation | Caution |
| Anticholinergics | Additive effects | Avoid |
Clinical Trial Design Deep Dive
Randomization and Blinding
The trial uses quadruple-masking:
Treatment Period
| Phase | Duration | Purpose |
|-------|----------|---------|
| Screening | 2-4 weeks | Eligibility confirmation |
| Baseline | Day 0 | Pre-treatment assessments |
| Treatment | 8 weeks | Active intervention |
| Washout | 2 weeks | Drug clearance |
| Follow-up | 8 weeks | Long-term assessment |
Visit Schedule
| Visit | Timing | Assessments |
|-------|--------|-------------|
| V1 | Screening | Medical history, cognitive testing |
| V2 | Baseline | CMAI, NPI-NH, safety |
| V3 | Week 2 | Efficacy, safety, PK |
| V4 | Week 4 | Full assessment, labs |
| V5 | Week 8 | Primary endpoint, safety |
| V6 | Week 10 | Washout |
| V7 | Week 16 | Follow-up |
Clinical Outcome Measures
Cohen-Mansfield Agitation Inventory (CMAI)
The CMAI is the primary endpoint:
| Domain | Items | Scoring |
|--------|-------|---------|
| Physical aggression | 8 | 29-203 total |
| Verbal aggression | 6 | Higher = worse |
| Non-aggressive behavior | 15 | |
Subscales
| Subscale | Items | Examples |
|----------|-------|----------|
| Physically aggressive | 1-8 | Hitting, kicking |
| Verbally aggressive | 9-14 | Cursing, screaming |
| Non-aggressive | 15-29 | Pacing, complaining |
Neuropsychiatric Inventory-Nursing Home (NPI-NH)
Comprehensive behavioral assessment:
| Domain | Maximum Score |
|--------|---------------|
| Delusions | 12 |
| Hallucinations | 12 |
| Agitation | 12 |
| Depression | 12 |
| Anxiety | 12 |
| Apathy | 12 |
| Disinhibition | 12 |
| Irritability | 12 |
| Motor disturbance | 12 |
| Nighttime behavior | 12 |
| Appetite | 12 |
| Total | 144 |
Standardized Mini-Mental State Examination (sMMSE)
| Domain | Items | Score |
|--------|-------|-------|
| Orientation | 10 | 10 |
| Registration | 3 | 3 |
| Attention | 5 | 5 |
| Recall | 3 | 3 |
| Language | 8 | 8 |
| Visuospatial | 1 | 1 |
| Total | | 30 |
Safety and Monitoring
Common Adverse Events
| Event | Frequency | Management |
|-------|-----------|------------|
| Sedation | 30-40% | Dose reduction |
| Dizziness | 20-30% | Fall precautions |
| Dry mouth | 15-25% | Hydration |
| Weight gain | 10-15% | Monitoring |
| Constipation | 10-15% | Laxatives |
| Confusion | 5-10% | Assessment |
Serious Adverse Event Monitoring
| Event | Monitoring | Reporting |
|-------|------------|------------|
| Cardiovascular | Vital signs, ECG | Immediate |
| Psychiatric | Mood, behavior | Regular |
| Respiratory | Pulse ox | Per protocol |
| Falls | Incidence tracking | Continuous |
Contraindications
| Contraindication | Rationale |
|------------------|-----------|
| Psychosis | Exacerbation risk |
| Substance abuse | Dependence |
| Severe cardiac disease | Arrhythmia risk |
| Hepatic impairment | Metabolism |
Comparison with Other Approaches
Pharmacological Options
| Treatment | Mechanism | CMAI Effect | Key Limitation |
|-----------|-----------|-------------|----------------|
| Nabilone | CB1/CB2 agonist | Moderate | Requires monitoring |
| Risperidone | D2 antagonist | Moderate | Extrapyramidal effects |
| Quetiapine | Multi-receptor | Low-moderate | Sedation, metabolic |
| Trazodone | 5-HT antagonist | Low | Sedation |
| Citalopram | SSRI | Variable | Slow onset |
Non-Pharmacological Approaches
| Intervention | Evidence | Implementation |
|--------------|----------|----------------|
| Music therapy | Moderate | Easy |
| Validation therapy | Moderate | Training needed |
| Exercise | Moderate | Physical ability |
| Sensory modulation | Variable | Staff training |
| Environmental modification | Variable | Cost |
Regulatory Context
Health Canada
Nabilone is approved in Canada for:
- Chemotherapy-induced nausea (1985)
- Refractory pain (2007)
Use for AD agitation would be:
- Off-label initially
- Potential for new indication
FDA
- Not approved for agitation
- Potential for orphan designation
- Accelerated pathway possible
Clinical Practice Implications
If approved:
- First-line for refractory agitation
- Second-line before antipsychotics
- Preferred over off-label antipsychotics
Cost-Effectiveness
Treatment Costs
| Component | Cost |
|-----------|------|
| Nabilone (monthly) | $200-400 |
| Monitoring visits | $100-200 |
| Lab work | $50-100 |
| Total | $350-700/month |
Comparison
| Treatment | Monthly Cost | Effectiveness |
|-----------|--------------|---------------|
| Nabilone | $350-700 | Moderate |
| Risperidone | $50-100 | Moderate |
| Quetiapine | $100-200 | Low-moderate |
| Hospitalization | $5000+ | High |
Value Considerations
- Reduced caregiver burden
- Delayed institutionalization
- Improved quality of life
- Reduced crisis interventions
Patient Selection
Ideal Candidates
| Factor | Criteria |
|--------|-----------|
| Diagnosis | AD with agitation |
| Severity | Moderate agitation (CMAI > 50) |
| Cognitive | sMMSE < 24 |
| Failure | Non-pharmacological failed |
| Contraindications | None |
Patients to Avoid
| Factor | Reason |
|--------|--------|
| Active psychosis | Exacerbation risk |
| Cardiovascular disease | Arrhythmia risk |
| Substance abuse history | Dependence risk |
| Severe liver disease | Metabolism |
Long-Term Considerations
Extension Studies
| Focus | Duration | Endpoints |
|-------|----------|-----------|
| Safety | 12 months | SAEs |
| Durability | 6 months | CMAI maintenance |
| Tolerability | 12 months | AE rate |
Post-Market Surveillance
- Registry monitoring
- Spontaneous reporting
- Long-term outcomes
Research Gaps
Current Limitations
Future Research Needs
| Area | Priority |
|------|----------|
| Severe agitation | High |
| Long-term safety | High |
| Combination therapy | Moderate |
| Biomarkers | Moderate |
| Pre-symptomatic | Low |
Related Conditions
Parkinson's Disease Psychosis
Cannabinoids have been studied in PDP:
- Similar CB1 mechanisms
- Different safety profile
- Ongoing trials
Lewy Body Dementia
- Often more responsive to cannabinoids
- Different AE profile
- Research ongoing
Frontotemporal Dementia
- Less evidence
- Different mechanisms
- Caution needed
Implementation
Clinical Integration
If approved, implementation pathway:
Caregiver Education
Key points for caregivers:
- Realistic expectations
- Side effect monitoring
- Importance of compliance
- Reporting protocols
Conclusion
The NAB-IT trial represents an important step in addressing agitation in Alzheimer's disease, a highly prevalent and challenging symptom with limited treatment options. Nabilone's unique mechanism targeting the endocannabinoid system offers a novel approach that may provide benefits beyond traditional pharmacological interventions.
The trial's rigorous design, including quadruple blinding and comprehensive outcome measures, will provide high-quality evidence for nabilone's efficacy and safety in this population. Given the significant impact of agitation on patients, caregivers, and healthcare systems, any effective treatment would represent a major advance in dementia care.
Success in this trial would not only provide a new therapeutic option but also advance our understanding of the endocannabinoid system's role in neuropsychiatric symptoms of dementia, potentially opening doors for additional cannabinoid-based therapies in neurodegenerative diseases.
Related Pages
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Agitation in Dementia](/mechanisms/neuropsychiatric-symptoms-dementia)
- [Cannabinoids in Neurodegeneration](/therapeutics/cannabinoid-therapy)
- [Sunnybrook Health Sciences Centre](/institutions/sunnybrook-health-sciences-centre)
- [Neuropsychiatric Symptoms](/symptoms/neuropsychiatric-symptoms)
References
Related Pages
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Agitation in Dementia](/mechanisms/neuropsychiatric-symptoms-dementia)
- [Cannabinoids in Neurodegeneration](/mechanisms/cannabinoid-neuroprotection)
- [Sunnybrook Health Sciences Centre](/institutions/sunnybrook-health-sciences-centre)
See Also
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's Disease](/diseases/parkinsons-disease)
External Links
- [PubMed](https://pubmed.ncbi.nlm.nih.gov/)
- [KEGG Pathways](https://www.genome.jp/kegg/pathway.html)
References
▸Metadataorigin_type: v1_polymorphic_backfill
| slug | clinical-trials-nabilone-nab-it |
| kg_node_id | None |
| entity_type | clinical |
| origin_type | v1_polymorphic_backfill |
| source_table | wiki_pages |
| wiki_page_id | wp-ad366a507db3 |
| __merged_from | {'merged_at': '2026-05-13', 'unprefixed_id': 'clinical-trials-nabilone-nab-it'} |
| _schema_version | 1 |
No provenance edges found
Use ?embed=1 to load the artifact without SciDEX chrome — suitable for iframing into wiki pages or external sites.
<iframe src="http://scidex.ai/artifact/wiki-clinical-trials-nabilone-nab-it?embed=1" width="100%" height="600" style="border:0;border-radius:8px"></iframe>
[NAB-IT: Nabilone for Agitation in Alzheimer's Disease](http://scidex.ai/artifact/wiki-clinical-trials-nabilone-nab-it)
http://scidex.ai/artifact/wiki-clinical-trials-nabilone-nab-it