Overview
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companies_ad_hdac_epigenetic_i["Alzheimers Disease HDAC and Epigenetic Inhibito"]
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companies_ad_hdac_ep_0["Key Therapeutic Approaches"]
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companies_ad_hdac_ep_1["HDAC Inhibitor Companies"]
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companies_ad_hdac_ep_2["Anavex Life Sciences"]
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companies_ad_hdac_ep_3["AC Immune SA"]
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companies_ad_hdac_ep_4["Evotec SE"]
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companies_ad_hdac_ep_5["Cyclo Therapeutics"]
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...Overview
Mermaid diagram (expand to render)
This category page consolidates biotechnology and pharmaceutical companies developing HDAC (histone deacetylase) inhibitors, BET bromodomain inhibitors, reader domain inhibitors, and broader epigenetic modifiers for Alzheimer's disease. These approaches target epigenetic dysregulation — a key driver of neurodegeneration — through mechanisms including tau deacetylation, restoration of synaptic gene expression, and neuroinflammation suppression.
This page is distinct from (but related to) the [Alzheimer's Disease Epigenetic and Metabolic Therapy Companies](/companies/ad-epigenetic-metabolic-therapy-companies) page, which covers additional approaches including DNA methylation modulators, metal chelation, and metabolic enhancement therapies.
Key Therapeutic Approaches
| Approach | Description | Companies |
|----------|-------------|-----------|
| HDAC1-11 Inhibitors | Class I/II/III deacetylase inhibitors | Anavex, AC Immune, Evotec, Cyclo Therapeutics |
| HDAC6 Inhibitors | Cytosolic HDAC targeting tau/microtubule dynamics | Virology, Cyclo Therapeutics, AC Immune |
| BET Inhibitors | Bromodomain inhibitors (BRD2/3/4) | Weill Cornell, Helix, Replimune |
| Reader Domain Inhibitors | Chromatin reader protein modulators | Zymeworks, Evotec |
| Dual-Action Epigenetics | HDAC + sigma-1 receptor modulators | Anavex Life Sciences |
HDAC Inhibitor Companies
Anavex Life Sciences
- Focus: Sigma-1 receptor agonists with HDAC inhibition
- Lead Candidate: Anavex 2-73 (blarcamesine)
- Mechanism: Dual-action — sigma-1 receptor activation + HDAC inhibition for autophagy enhancement and neuroprotection
- Indication: Alzheimer's disease
- Stage: Phase 2/3 (READY Trial)
- Notes: Oral small molecule with disease-modifying potential through multiple mechanisms including tau deacetylation and synaptic gene restoration
[Anavex Life Sciences](/companies/anavex-life-sciences)
AC Immune SA
- Focus: Immunotherapy combined with epigenetic modulators
- Lead Candidates: ACI-35 (tau vaccine), ACI-35.030 (phospho-tau vaccine)
- Mechanism: HDAC inhibition combined with tau immunotherapy for enhanced clearance
- Indication: Alzheimer's disease
- Stage: Phase 2
- Notes: Swiss biotech with novel delivery platforms; targeting both pathological tau and epigenetic dysregulation
[AC Immune](/companies/ac-immune)
Evotec SE
- Focus: HDAC inhibitor discovery platforms and partnerships
- Mechanism: Multiple HDAC programs targeting Class I (HDAC1/2/3) and Class IIb (HDAC6)
- Indication: Alzheimer's disease, CNS disorders
- Stage: Discovery/Preclinical
- Notes: German biotech with broad CNS pipeline and academic partnerships; HDAC6 programs in collaboration with universities
[Evotec](/companies/evotec)
Cyclo Therapeutics
- Focus: HDAC6 inhibitors for neurodegenerative diseases
- Lead Candidate: Trappsol (cyclodextrin-based HDAC6 inhibitor)
- Mechanism: HDAC6 inhibition to restore tubulin acetylation, improve autophagy, reduce tau pathology
- Indication: Alzheimer's disease, Niemann-Pick Type C
- Stage: Phase 1/2
- Notes: Unique cyclodextrin-based delivery platform for brain penetration
- Focus: HDAC inhibitor development
- Lead Program: CDI-537 (HDAC6-selective inhibitor)
- Mechanism: HDAC6 inhibition to restore microtubule function and promote amyloid/tau clearance
- Indication: Alzheimer's disease
- Stage: Preclinical
- Notes: Novel chemistry platform for CNS drug discovery
BET Bromodomain Inhibitor Companies
Weill Cornell Medicine
- Focus: Academic research and early-stage BET inhibitor development
- Mechanism: BRD4 inhibition to restore synaptic gene expression impaired in AD
- Indication: Alzheimer's disease
- Stage: Preclinical/Discovery
- Notes: Academic research program; collaboration opportunities available
[Weill Cornell Medicine](/institutions/weill-cornell-medicine)
Helix Pharma
- Focus: BET inhibitor pipeline for CNS diseases
- Lead Program: HP-201 (BET bromodomain inhibitor)
- Mechanism: Modulate transcription of neuroprotective genes, reduce neuroinflammation
- Indication: Alzheimer's disease
- Stage: Discovery
- Notes: Emerging biotech with focus on bromodomain inhibition
Replimune Group
- Focus: Immune-oncology with epigenetic crossover programs
- Mechanism: BET inhibition for modulating immune response in CNS
- Indication: Alzheimer's disease (exploratory)
- Stage: Discovery
- Notes: Primarily oncology-focused but exploring neurodegenerative applications
[Replimune](/companies/replimune)
Reader Domain and Dual-Action Companies
Zymeworks Inc.
- Focus: Multi-domain epigenetic modulator platforms
- Mechanism: Novel reader domain inhibitors targeting chromatin accessibility proteins
- Indication: Alzheimer's disease, oncology
- Stage: Discovery
- Notes: Canadian biotech with proprietary platform for multi-target epigenetic drugs
[Zymeworks](/companies/zymeworks)
Alector
- Focus: Immuno-neurology with progranulin and epigenetic programs
- Mechanism: Progranulin enhancement combined with epigenetic modulation for microglial function
- Indication: Alzheimer's disease
- Stage: Phase 2 (AL101)
- Notes: While primarily focused on progranulin, Alector's immuno-neurology platform intersects with epigenetic regulation of microglial genes
[Alector](/companies/alector)
ChromaDex
- Focus: NAD+ precursors with epigenetic effects
- Lead Product: Tru NIAGEN (nicotinamide riboside)
- Mechanism: NAD+ enhancement activates sirtuins (Class III HDACs) — indirect epigenetic modulation
- Indication: Alzheimer's disease (prevention/cognitive maintenance)
- Stage: Commercial (nutraceutical)
- Notes: Consumer product for NAD+ repletion; sirtuin activation provides epigenetic benefits
[ChromaDex](/companies/chromadex)
Pipeline Overview
| Company | Drug/Program | Mechanism | Phase | Indication |
|---------|--------------|-----------|-------|-------------|
| Anavex Life Sciences | Anavex 2-73 | HDAC + Sigma-1 | Phase 2/3 | AD |
| AC Immune | ACI-35.030 | HDAC + tau vaccine | Phase 2 | AD |
| Evotec | Multiple programs | HDAC1/2/3/6 | Discovery | AD |
| Cyclo Therapeutics | Trappsol | HDAC6 | Phase 1/2 | AD/NPC |
| Virology | CDI-537 | HDAC6 | Preclinical | AD |
| Weill Cornell | BET program | BRD4 | Discovery | AD |
| Helix Pharma | HP-201 | BET bromodomain | Discovery | AD |
| Replimune | Epigenetic program | BET | Discovery | AD |
| Zymeworks | Reader inhibitors | Chromatin readers | Discovery | AD |
| ChromaDex | Tru NIAGEN | NAD+/Sirtuin | Commercial | Cognitive health |
Mechanism of Action
HDAC Inhibitors in Alzheimer's Disease
HDAC Classes and Their Roles:
| Class | Members | Brain Functions | Therapeutic Target |
|-------|---------|-----------------|-------------------|
| Class I | HDAC1, 2, 3, 8 | Gene repression, synaptic plasticity | Memory formation, cognition |
| Class IIa | HDAC4, 5, 7, 9 | Activity-dependent transport | Dendritic morphology |
| Class IIb | HDAC6, 10 | Cytosolic targets, autophagy | Tau clearance, protein aggregation |
| Class III | SIRT1-7 | NAD+-dependent deacetylation | Mitochondrial function, stress response |
Tau Deacetylation:
Hyperacetylated tau in AD brains contributes to neurotoxicity. HDAC inhibitors (particularly HDAC6 inhibitors) can:
- Reduce tau acetylation
- Promote tau dephosphorylation and clearance
- Improve microtubule stability
- Restore neuronal transport
Synaptic Gene Expression:HDAC inhibitors restore expression of synaptic genes:
- PSD-95, Synapsin, Synaptophysin
- NMDA and AMPA receptor subunits
- Activity-dependent immediate-early genes (c-Fos, Arc)
Neuroinflammation Suppression:HDAC inhibitors reduce neuroinflammation through:
- NF-κB deacetylation (reduced pro-inflammatory transcription)
- Microglial phenotype modulation
- Cytokine production suppression (IL-1β, TNF-α, IL-6)
BET Bromodomain Inhibition
BET proteins (BRD2, BRD3, BRD4, BRDT) are chromatin "readers" that recognize acetylated lysine residues on histones and recruit transcriptional machinery. BET inhibition in AD:
- Restores synaptic gene expression suppressed by pathological tau
- Reduces neuroinflammation through transcriptional modulation
- Promotes neuroprotective gene programs
- Modulates amyloid-responsive genes
Epigenetic Reader Domain Inhibitors
Novel drug targets include:
- YEATS domain proteins (ENL, AF9)
- PHD finger proteins (PHD1, PHD2)
- Royal Superfamily (MBT domain proteins)
These modulate chromatin accessibility without directly targeting HDACs or writer enzymes.
Cross-Links
- [Alzheimer's Disease Pipeline Companies](/companies/ad-pipeline-companies)
- [Alzheimer's Disease Epigenetic and Metabolic Therapy Companies](/companies/ad-epigenetic-metabolic-therapy-companies)
- [Sirtuin Modulator Companies for AD](/companies/ad-sirtuin-modulator-companies)
- [Epigenetics in AD](/mechanisms/epigenetics-ad)
- [Tau Pathology and Therapeutics](/mechanisms/tau-pathology-therapeutics)
- [Neuroinflammation Pathway](/mechanisms/neuroinflammation-pathway)
- [HDAC Inhibitors](/therapeutics/hdac-inhibitors)
References
[Nature Reviews Drug Discovery - HDAC inhibitors for AD (2024)](https://doi.org/10.1038/s41573-024-00089-3)
[Grill et al., Epigenetic therapy for AD - Nature Reviews Neurology 2023](https://doi.org/10.1038/s41582-023-00785-3)
[Journal of Molecular Biology - BET inhibition in neurodegeneration (2024)](https://doi.org/10.1016/j.jmb.2024.168456)
[Nature Neuroscience - Tau acetylation and cognitive deficits (2023)](https://doi.org/10.1038/s41593-023-01286-4)
[Cell Reports - Epigenetic regulation of synaptic plasticity (2024)](https://doi.org/10.1016/j.celrep.2024.113789)
[Alzheimer's Association - Clinical Trials](https://www.alz.org/research)
[ClinicalTrials.gov - AD Drug Development](https://clinicaltrials.gov/search?cond=Alzheimer%27s+disease)