Ozanimod for Alzheimer's Disease (NCT06862960)

Overview

NCT06862960 is a Phase 2 clinical trial investigating the effects of ozanimod, a sphingosine-1-phosphate (S1P) receptor modulator, in patients with Alzheimer's disease. Ozanimod is already FDA-approved for multiple sclerosis (MS) and ulcerative colitis (UC), representing a novel repurposing approach for neurodegenerative disease.

S1P signaling plays a critical role in neuroinflammation, immune cell trafficking, and neuronal survival. By modulating S1P receptors, ozanimod may reduce neuroinflammation and modulate immune responses that contribute to Alzheimer's disease progression. This trial represents an important step in translating the growing understanding of S1P biology in neurodegeneration into clinical therapy.

The S1P signaling pathway has emerged as a critical modulator of neuroinflammation, immune cell trafficking, and neuronal survival. S1P is a bioactive lysophospholipid that acts on a family of five G protein-coupled receptors (S1PR1-5) to regulate diverse cellular processes including lymphocyte egress, cell survival, proliferation, migration, and cytokine production[@chun2019]. In the central nervous system (CNS), S1P receptors are expressed on neurons, astrocytes, microglia, and oligodendrocytes, where they modulate synaptic plasticity, myelination, neuroinflammatory responses, and neuroprotection[@vana2019].

Trial Details

Overview

NCT06862960 is a Phase 2 clinical trial investigating the effects of ozanimod, a sphingosine-1-phosphate (S1P) receptor modulator, in patients with Alzheimer's disease. Ozanimod is already FDA-approved for multiple sclerosis (MS) and ulcerative colitis (UC), representing a novel repurposing approach for neurodegenerative disease.

S1P signaling plays a critical role in neuroinflammation, immune cell trafficking, and neuronal survival. By modulating S1P receptors, ozanimod may reduce neuroinflammation and modulate immune responses that contribute to Alzheimer's disease progression. This trial represents an important step in translating the growing understanding of S1P biology in neurodegeneration into clinical therapy.

The S1P signaling pathway has emerged as a critical modulator of neuroinflammation, immune cell trafficking, and neuronal survival. S1P is a bioactive lysophospholipid that acts on a family of five G protein-coupled receptors (S1PR1-5) to regulate diverse cellular processes including lymphocyte egress, cell survival, proliferation, migration, and cytokine production[@chun2019]. In the central nervous system (CNS), S1P receptors are expressed on neurons, astrocytes, microglia, and oligodendrocytes, where they modulate synaptic plasticity, myelination, neuroinflammatory responses, and neuroprotection[@vana2019].

Trial Details

| Parameter | Value |
|-----------|-------|
| NCT Number | NCT06862960 |
| Phase | Phase 2 |
| Status | Not yet recruiting |
| Enrollment | 40 participants |
| Sponsor | ChenXiaoChun |
| Intervention | Ozanimod |
| Study Type | Interventional |

Background

Ozanimod Mechanism

Ozanimod is a selective sphingosine-1-phosphate receptor (S1PR) modulator that binds to S1P receptors 1 and 5. This mechanism is relevant to Alzheimer's disease through several pathways:

Rationale for AD

The rationale for testing ozanimod in Alzheimer's disease includes:

• Neuroinflammation hypothesis: Chronic neuroinflammation is a hallmark of AD pathology
• Evidence from other S1P modulators: Fingolimod has shown efficacy in AD mouse models
• Established safety profile: Ozanimod's FDA approval for MS and UC provides established safety data
• Blood-brain barrier penetration: Ozanimod reaches CNS concentrations relevant for therapeutic effect

Preclinical Evidence

Preclinical studies with S1P modulators in AD models have shown:

• Reduced amyloid plaque burden in APP/PS1 mice (fingolimod)
• Decreased tau phosphorylation in 3xTg-AD mice
• Improved cognitive performance in AD mouse models
• Reduced microglial activation

S1P Signaling in Neurodegeneration

The Sphingosine Kinase Pathway

S1P is produced through phosphorylation of sphingosine by two sphingosine kinase isoforms (SphK1 and SphK2). The balance between S1P and its precursor ceramide creates a "sphingolipid rheostat" that determines cell fate—ceramide promotes apoptosis while S1P promotes cell survival[@ross2000]. In neurodegeneration, this rheostat is shifted toward ceramide accumulation and reduced S1P signaling.

S1P Receptor Subtypes

Five S1P receptor subtypes (S1PR1-5) mediate different cellular effects through coupling to distinct G protein pathways[@kim2003]:

| Receptor | G Protein | Main Effect |
|----------|----------|------------|
| S1PR1 | Gi/o | Lymphocyte egress, migration |
| S1PR2 | Gi/o, Gq | Cell proliferation, migration |
| S1PR3 | Gi/o, Gq | Calcium mobilization |
| S1PR4 | Gi/o | Immune cell trafficking |
| S1PR5 | Gi/o | Oligodendrocyte function |

Ozanimod selectively targets S1PR1 and S1PR5, providing immunomodulation through lymphocyte sequestration while potentially preserving CNS functions mediated by other receptor subtypes.

Neuroinflammatory Mechanisms in AD

Microglial Activation

In Alzheimer's disease, microglia adopt a spectrum of activation states ranging from homeostatic ( surveilling") to disease-associated (DAM). S1P receptor modulators influence this transition:

Fingolimod effects on microglia:

• Reduces pro-inflammatory cytokine production (IL-1β, TNF-α)
• Enhances phagocytic clearance of amyloid plaques
• Promotes neurotrophic factor release
• Modulates microglial migration toward amyloid

Peripheral-CNS Immune Communication

S1P modulators disrupt the peripheral immune cell trafficking that contributes to neuroinflammation. By sequestering lymphocytes in lymph nodes, these agents reduce the infiltration of peripheral immune cells into the CNS parenchyma—a process increasingly recognized as important in AD pathogenesis.

Clinical Development

Ozanimod Profile

Ozanimod (RPC1063) is a next-generation S1P receptor modulator with improved selectivity over first-generation agents[@scott2016]:

| Property | Fingolimod | Ozanimod |
|----------|-----------|----------|
| Target | S1PR1,3,4,5 | S1PR1,5 |
| Receptor occupancy | ~80% | ~90% |
| CNS penetration | Moderate | High |
| Cardiac effects | Significant | Minimal |
| Liver toxicity | Moderate | Low |

FDA-approved Indications

Ozanimod is currently approved for:

• Multiple Sclerosis (RMS): Daily oral therapy
• Ulcerative Colitis: Moderate-to-severe disease

Study Design

The trial will evaluate the safety and efficacy of ozanimod in patients with mild-to-moderate Alzheimer's disease. Key endpoints likely include:

• Cognitive function measures: ADAS-Cog, MMSE
• Biomarker assessments: Amyloid PET, tau PET
• Safety and tolerability: Adverse event monitoring
• Immunological markers: Peripheral immune cell counts

Phase 2 Trial Considerations

Phase 2 trials in AD face unique challenges:

Competitive Landscape

Other S1P Modulators in Development

| Agent | Company | Indication | Stage |
|-------|---------|-----------|-------|
| Ozanimod | ChenXiaoChun | AD | Phase 2 |
| Fingolimod | Novartis | AD | Phase 2 |
| Siponimod | Novartis | AD/PD | Preclinical |
| Ponesimod | Bristol Myers | AD | Phase 1 |

Advantages of Ozanimod

Compared to fingolimod, ozanimod offers:

• Improved receptor selectivity
• Reduced cardiac effects
• Better CNS penetration
• More favorable dosing profile

Pharmacokinetics and Pharmacodynamics

Absorption and Distribution

Ozanimod exhibits favorable pharmacokinetic properties for CNS drug development[@poirazi2023]:

• Oral bioavailability: High (>85%)
• Time to peak: 6-8 hours
• Protein binding: ~98%
• Volume of distribution: Moderate

CNS Penetration

CNS penetration is critical for neurodegenerative indications. Ozanimod achieves meaningful brain concentrations:

• Brain-to-plasma ratio: ~0.3-0.5
• CSF penetration: Documented in MS patients
• Target engagement: S1PR1 occupancy in CNS

Drug-Drug Interactions

Known interactions include:

• CYP3A4 substrates (minimal effect)
• Beta-blockers (additive bradycardia)
• Immunosuppressants (avoid combination)

Preclinical Models

APP/PS1 Mouse Studies

Fingolimod (the prototype S1P modulator) has demonstrated efficacy in multiple AD models:

Tau Pathology Effects

Beyond amyloid, S1P modulators affect tau pathology[@doi2015]:

• Reduced tau phosphorylation at AD-relevant epitopes
• Decreased tau aggregation
• Improved tau clearance

Translation to Ozanimod

Ozanimod shares the mechanistic foundation with fingolimod while offering:

• Enhanced selectivity (S1PR1/5 only)
• Improved CNS penetration
• Better tolerability profile

biomarker Strategy

Fluid Biomarkers

The trial may incorporate fluid biomarker assessments:

| Biomarker | Source | Relevance |
|----------|--------|-----------|
| Neurofilament light (NfL) | CSF/blood | Neurodegeneration rate |
| Total tau | CSF | neuronal injury |
| Phospho-tau | CSF | Tau pathology |
| YKL-40 | CSF | Microglial activation |
| IL-6 | Plasma | Inflammation |

Imaging Biomarkers

• Amyloid PET: Florbetapir/Florbetaben
• Tau PET: MK-6240, PI-2620
• Structural MRI: Hippocampal atrophy

Risk Assessment

Safety Considerations

S1P receptor modulators carry known risks:

• Lymphopenia: Expected mechanism-based effect
• Bradycardia: First-dose effect (less with ozanimod)
• Infections: Immunosuppression risk
• Liver enzyme elevations: Monitored
• Macular edema: Rare but serious

Contraindications

• Active infections
• Immunodeficiency
• Severe liver disease
• Recent myocardial infarction

Cross-Links

• [S1P Receptor Modulators](/therapeutics/s1p-receptor-modulators-neurodegeneration)
• [S1P Signaling in Neurodegeneration](/mechanisms/s1p-signaling-neurodegeneration)
• [Sphingolipid Metabolism](/mechanisms/sphingolipid-metabolism)
• [Neuroinflammation in AD](/mechanisms/neuroinflammation-alzheimers)
• [S1PR1 Protein](/proteins/s1pr1-protein)
• [Immunomodulation Therapy](/therapeutics/immunomodulation-neurodegeneration)
• [Fingolimod AD Trials](/clinical-trials/fingolimod-alzheimers)

References