COMMETS - Semaglutide for MCI/Metabolic Syndrome (NCT06072963)

COMMETS (NCT06072963): Semaglutide + Intranasal Insulin for MCI/Metabolic Syndrome

Overview

Study Title: Combination MCI Metabolic Syndrome (COMMETS) Intervention: Semaglutide (GLP-1 RA) + Intranasal Insulin Phase: Phase 2 Participants: 80 (planned) Status: Recruiting Sponsor: Alzheimer's Therapeutic Research Institute, University of Southern California ClinicalTrials.gov Identifier: [NCT06072963](https://clinicaltrials.gov/study/NCT06072963) Study Duration: 52 weeks (12-month treatment)

Rationale

Type 3 Diabetes Hypothesis

Alzheimer's disease is increasingly recognized as a metabolic disorder of the brain, sometimes called "Type 3 Diabetes":

Brain Insulin Resistance:

• AD brains show reduced insulin receptor density and signaling
• This occurs independently of peripheral insulin resistance
• Insulin signaling is critical for synaptic plasticity, memory formation, and amyloid clearance

COMMETS (NCT06072963): Semaglutide + Intranasal Insulin for MCI/Metabolic Syndrome

Overview

Study Title: Combination MCI Metabolic Syndrome (COMMETS) Intervention: Semaglutide (GLP-1 RA) + Intranasal Insulin Phase: Phase 2 Participants: 80 (planned) Status: Recruiting Sponsor: Alzheimer's Therapeutic Research Institute, University of Southern California ClinicalTrials.gov Identifier: [NCT06072963](https://clinicaltrials.gov/study/NCT06072963) Study Duration: 52 weeks (12-month treatment)

Rationale

Type 3 Diabetes Hypothesis

Alzheimer's disease is increasingly recognized as a metabolic disorder of the brain, sometimes called "Type 3 Diabetes":

Brain Insulin Resistance:

• AD brains show reduced insulin receptor density and signaling
• This occurs independently of peripheral insulin resistance
• Insulin signaling is critical for synaptic plasticity, memory formation, and amyloid clearance

• Obesity: Adipokines and chronic inflammation affect brain function
• Hypertension: Cerebrovascular damage reduces cerebral perfusion
• Dyslipidemia: Lipid metabolism intersects with amyloid processing
• Insulin resistance: Direct effect on brain insulin signaling

• Midlife metabolic syndrome increases late-life AD risk by 2-3x
• Type 2 diabetes patients have 50-100% higher AD incidence
• Insulin resistance correlates with amyloid burden in cognitively normal adults

Combination Approach Rationale

Semaglutide (GLP-1 Receptor Agonist):

• Addresses peripheral insulin sensitivity
• Crosses BBB at low levels but exerts central effects via peripheral-cerebral crosstalk
• Reduces systemic inflammation (IL-6, TNF-α)
• GLP-1 receptors expressed on neurons, astrocytes, and microglia
• Preclinical data: Reduces amyloid plaques, improves cognition in AD models

• Direct delivery to brain without systemic exposure
• Targets central insulin signaling impairment
• Bypasses peripheral insulin resistance
• Dosing: 20-40 IU twice daily shown safe in prior trials
• Effects: Improves memory, cerebral glucose metabolism

• Complementary mechanisms targeting different aspects of brain insulin resistance
• Semaglutide improves peripheral → central signaling
• Intranasal insulin directly activates central receptors

Mechanism of Action

Semaglutide

GLP-1 Biology:

• Glucagon-like peptide-1 is an incretin hormone
• Secreted by L-cells in response to food intake
• Enhances glucose-dependent insulin secretion
• Also acts on CNS GLP-1R expressed in:
• Hippocampus (memory circuits)
• Cortex (executive function)
• Hypothalamus (metabolic control)
• Limbic system (emotional processing)

• Reduces microglial activation
• Decreases pro-inflammatory cytokine production
• Modulates NLRP3 inflammasome

• Reduces amyloid-beta production (via BACE modulation)
• Enhances amyloid clearance
• Inhibits aggregation

• Reduces tau phosphorylation
• Decreases tau propagation

• Enhances synaptic plasticity
• Increases neurotrophic factor expression (BDNF)
• Reduces excitotoxicity

• Improves cerebral glucose metabolism
• Reduces oxidative stress
• Enhances mitochondrial function

Intranasal Insulin

Delivery Method:

• Nasal passages to olfactory bulb and cribriform plate
• Direct transport along olfactory and trigeminal nerves
• Bypasses blood-brain barrier
• Achieves CSF concentrations 2-4x plasma

• Activates PI3K/Akt signaling pathway
• Enhances GSK-3β inhibition (reduces tau phosphorylation)
• Improves synaptic plasticity via NMDA receptor modulation
• Increases cerebral blood flow

• SPRINT-AD trial: Intranasal insulin improved cognition in MCI/AD
• Effect size: 0.3-0.5 SD improvement in memory
• Safety established in >500 patients across trials

Study Design

Population

Target: Adults with MCI due to AD + metabolic syndrome

Inclusion Criteria:

• Age 55-85 years
• MCI diagnosis (clinical and cognitive criteria)
• Metabolic syndrome (≥3 of 5 criteria):
• Waist circumference ≥102 cm (M) / ≥88 cm (F)
• Triglycerides ≥150 mg/dL
• HDL <40 mg/dL (M) / <50 mg/dL (F)
• BP ≥130/85 mmHg or on antihypertensives
• Fasting glucose ≥100 mg/dL or on DM medications
• Confirmed amyloid positivity (PET or CSF)
• Stable medications for 30 days

• Type 1 diabetes
• Active cardiovascular events
• Severe psychiatric conditions
• MRI contraindications

Arms

• Active: Semaglutide weekly injection + intranasal insulin BID
• Placebo: Matching injection + nasal spray

Schedule

Semaglutide:

• Start: 0.25 mg weekly
• Titrate: 0.5 mg at week 4, 1.0 mg at week 8
• Maintain: 1.0 mg weekly through week 52

• 20 IU twice daily throughout study
• Device: ViaNase or comparable nasal delivery

Outcome Measures

Primary Endpoints (Week 52)

Secondary Endpoints

Cognitive:

• MMSE (Mini-Mental State Examination)
• RAVLT (Rey Auditory Verbal Learning Test)
• Trail Making Test A/B

• ADCS-ADL (Activities of Daily Living)
• CDR-SB (Clinical Dementia Rating Sum of Boxes)

• CSF Aβ42/40, total tau, p-tau181
• Plasma NfL (neurofilament light chain)
• Inflammatory markers (IL-6, TNF-α)

• HOMA-IR (insulin sensitivity)
• HbA1c
• Lipid panel

Exploratory

• Amyloid PET (Centiloid change)
• Structural MRI (hippocampal volume)
• Gut microbiome analysis

Safety Monitoring

Semaglutide Known Risks:

• GI symptoms (nausea, vomiting, diarrhea) - usually transient
• Gallbladder disease (rare)
• Pancreatitis (rare)
• Thyroid C-cell tumors (not observed in humans)

• Nasal irritation
• Hypoglycemia (minimal risk - no systemic absorption expected)
• Sinus congestion

• Additive GI effects
• Monitor for hypoglycemia in diabetic patients
• Assess cardiovascular safety given population risk

Current Status

As of 2026, enrollment ongoing at multiple US sites.

Timeline:

• Enrollment: 2025-2026
• Primary completion: 2027
• Results expected: 2027-2028

Implications

If Positive

• First trial combining GLP-1 RA + intranasal insulin
• Could validate Type 3 diabetes hypothesis
• May establish new treatment paradigm for AD with metabolic comorbidity

Challenges

• Recruitment of MCI + metabolic syndrome may be challenging
• Compliance with two delivery methods (injection + nasal spray)
• Metabolic baseline variability across participants

References

Related Pages

• [Brain Insulin Signaling](/entities/brain-insulin-signaling)](/entities)
• [Type 3 Diabetes Hypothesis](/diseases/alzheimers-diabetes-connection)
• [GLP-1 in Neurodegeneration](/experiments/glp1-neuroprotection)](/experiments)
• [Metabolic Syndrome and AD Risk](/diseases/alzheimers-risk-factors)
• [Intranasal Drug Delivery](/techniques/intranasal-therapy)