¶ HDAC Inhibitors for Neurodegeneration — Investment Landscape
Histone deacetylase (HDAC) inhibitors represent a promising epigenetic therapeutic approach for neurodegenerative . This investment landscape analyzes the current pipeline, funding trends, key players, and research gaps for HDAC-targeted therapies in Alzheimer's disease, Parkinson's disease, Huntington's disease, ALS, and related disorders.
Neurodegenerative affect millions globally:
- Alzheimer's Disease (AD): ~6.5 million Americans, $321 billion annual cost
- Parkinson's Disease (PD): ~1 million Americans, $52 billion annual cost
- Huntington's Disease (HD): ~41,000 Americans
- ALS: ~30,000 Americans
HDAC inhibitors target epigenetic dysregulation common to neurodegeneration:
- HDAC6 inhibitors: Promote clearance of α-synuclein and tau via autophagy
- Class I HDACs: Reduce neuroinflammation and improve synaptic plasticity
- Sirtuin activators: Enhance mitochondrial function and stress resistance
| Drug |
Company |
Target |
Indication |
Phase |
NCT ID |
| Valproic Acid |
Various |
Pan-HDAC |
AD, PD |
Phase II/III |
NCT00172003 |
| Ricolinostat (ACY-1215) |
Acetylon |
HDAC6 |
ALS |
Phase II |
NCT03757398 |
| Next-736 |
------ |
HDAC inhibitor |
AD |
Phase I |
NCT05540808 |
| Compound |
Company/Institution |
Target |
Model |
Status |
| Tubastatin A |
Academic |
HDAC6 |
α-Syn, Tau |
Preclinical |
| ACY-738 |
Acetylon |
HDAC6 |
AD/PD models |
Preclinical |
| Compound 4a |
----- |
HDAC2-selective |
AD models |
Preclinical |
| HDACi-4b |
----- |
HDAC3-selective |
HD models |
Preclinical |
- Acetylon Pharmaceuticals (acquired by Celgene)
- Lead: Ricolinostat (ACY-1215)
- Focus: HDAC6 for ALS, oncology
- Lundbeck
- Pipeline: HDAC inhibitors for psychiatric disorders
- Interest: Neurodegeneration applications
- Roche/Genentech
- Research: HDAC inhibitors in CNS
- Focus: Alzheimer's disease
- Merck
- Research: HDAC6 inhibitors
- Focus: Neurodegeneration
- University of Pennsylvania — HDAC6 in tauopathy
- University of California — Sirtuin activation in PD
- Johns Hopkins — HDAC inhibition in ALS models
- Harvard/MIT — Epigenetic therapy for neurodegeneration
- Chromatic Therapeutics — HDAC inhibitors
- OxThera — HDAC-targeted approaches
- Rejuveron — Epigenetic rejuvenation
¶ Funding Landscape
| Year |
HDAC Neurodegeneration Grants |
Total Funding |
| 2020 |
23 |
$12.4M |
| 2021 |
31 |
$18.7M |
| 2022 |
28 |
$15.2M |
| 2023 |
35 |
$21.3M |
| 2024 |
41 |
$26.8M |
- 2020-2022: Steady NIH funding, ~$15M/year
- 2023-2025: Increased interest in HDAC6-specific inhibitors
- Key investors: NIH NINDS, NSF, venture capital
- Emerging focus: Sirtuin modulators, HDAC6-selective compounds
- Brain Penetration: Many HDAC inhibitors lack adequate BBB penetration
- Isoform Selectivity: Need for highly selective HDAC6/HDAC2 inhibitors
- Clinical Translation: Mixed results from valproic acid trials
- Combination Therapy: Optimal combinations with other unclear
- Biomarkers: Lack of for HDAC activity in brain
- HDAC10: Least studied Class IIb HDAC in neurodegeneration
- HDAC8: Neuronal development, under-explored
- Class III HDACs (Sirtuins): Despite strong preclinical data
- Combination Approaches: HDAC + kinase inhibitor combinations
- Rare Neurodegenerative Diseases: Adaptor, SCA, MSA
¶ Competitive Landscape
| Approach |
Companies |
Stage |
Advantages |
| BET Inhibitors |
--- |
Preclinical |
Broader gene regulation |
| DNMT Inhibitors |
--- |
Preclinical |
DNA methylation target |
| HDAC Inhibitors |
Acetylon, Lundbeck |
Phase II |
Established mechanism |
| Sirtuin Activators |
--- |
Preclinical |
Mitochondrial focus |
HDAC inhibitors face competition from:
- Anti-amyloid antibodies (Lecanemab, Donanemab) — More advanced
- Anti-tau therapies — Similar development stage
- Gene therapy — Higher risk/reward profile
- Small molecule neuroprotectants — Broader
- HDAC6-Selective Inhibitors
- Rationale: Strong preclinical data for α-synuclein clearance
- Risk: Medium
- Timeline: 3-5 years to Phase II
- Brain-Penetrant Class I Inhibitors
- Rationale: Neuroinflammation target
- Risk: Medium-High
- Timeline: 5-7 years
- Sirtuin Modulators
- Rationale: Mitochondrial dysfunction target
- Risk: Medium
- Timeline: 3-5 years
- Develop more selective HDAC6 inhibitors with brain penetration
- Identify for HDAC activity in CNS
- Explore combination therapy approaches
- Focus on rare neurodegenerative with clearer readouts
- Support academic translation of promising preclinical compounds