Alzheimer's Disease HSP70/HSP90 Chaperone and Protein Folding Therapy Companies

Overview

This category page covers biotechnology and pharmaceutical companies developing heat shock protein (HSP) modulators, pharmacological chaperones, and protein folding therapies for Alzheimer's disease (AD). Protein misfolding and aggregation — of amyloid-beta and tau — are central pathological features of AD, and the cellular proteostasis network that normally handles these proteins becomes progressively impaired with age and disease. Enhancing the chaperone system pharmacologically represents a disease-modifying strategy that addresses the root cause of protein pathology rather than downstream symptoms[@bukau2018][@kim2013].

The main therapeutic approaches in this space include:

• HSP70 modulators: Enhance the most versatile molecular chaperone to prevent aggregation and promote clearance
• HSP90 inhibitors: Trigger degradation of misfolded client proteins via the proteasome
• Pharmacological chaperones: Small molecules that bind and stabilize specific misfolded proteins
• Protein folding therapies: Agents that restore the cellular protein quality control system
• HSF1 activators: Increase expression of heat shock proteins endogenously

Key Companies

Gain Therapeutics (GANX)

Mechanism: Allosteric pharmacological chaperones targeting glucocerebrosidase (GCase) via SEE-Tx platform

Clinical Stage: Phase 1b (GT-02287 in GBA1-PD and idiopathic PD)

...

Overview

This category page covers biotechnology and pharmaceutical companies developing heat shock protein (HSP) modulators, pharmacological chaperones, and protein folding therapies for Alzheimer's disease (AD). Protein misfolding and aggregation — of amyloid-beta and tau — are central pathological features of AD, and the cellular proteostasis network that normally handles these proteins becomes progressively impaired with age and disease. Enhancing the chaperone system pharmacologically represents a disease-modifying strategy that addresses the root cause of protein pathology rather than downstream symptoms[@bukau2018][@kim2013].

The main therapeutic approaches in this space include:

• HSP70 modulators: Enhance the most versatile molecular chaperone to prevent aggregation and promote clearance
• HSP90 inhibitors: Trigger degradation of misfolded client proteins via the proteasome
• Pharmacological chaperones: Small molecules that bind and stabilize specific misfolded proteins
• Protein folding therapies: Agents that restore the cellular protein quality control system
• HSF1 activators: Increase expression of heat shock proteins endogenously

Key Companies

Gain Therapeutics (GANX)

Mechanism: Allosteric pharmacological chaperones targeting glucocerebrosidase (GCase) via SEE-Tx platform

Clinical Stage: Phase 1b (GT-02287 in GBA1-PD and idiopathic PD)

Background: Gain Therapeutics uses its proprietary SEE-Tx (Site-Directed Excipient Engineering) computational platform to identify small molecule chaperones that stabilize misfolded proteins. While the company's lead program GT-02287 targets GBA1-associated Parkinson's disease, Gain is also exploring GCase modulation in Alzheimer's disease where GCase dysfunction may contribute to amyloid pathology and lysosomal impairment[@gain2026][@gain2026a].

Key Programs:

• GT-02287: GCase activator for PD (Phase 1b), exploring AD relevance
• SEE-Tx platform: Allosteric modulators for multiple protein targets

Pipeline:
| Program | Indication | Target | Stage |
|---------|------------|--------|-------|
| GT-02287 | GBA1-PD / idiopathic PD | GCase | Phase 1b |
| GT-02287 | Alzheimer's Disease | GCase | Preclinical |
| GT-0234 | Pompe Disease | GAA | Preclinical |
| Undisclosed | GM1 Gangliosidosis | GLB1 | Preclinical |

Company: [Gain Therapeutics profile](/companies/gain-therapeutics)

Iduna Therapeutics

Mechanism: HSP70 modulators and aggregation inhibitors for synucleinopathies

Clinical Stage: IND-enabling studies (IDN-001)

Background: Iduna Therapeutics is developing small molecule chaperone modulators for Parkinson's disease and related neurodegenerative disorders. The company's lead candidate IDN-001 directly enhances HSP70 activity to promote clearance of misfolded proteins including alpha-synuclein and potentially tau. While focused on synucleinopathies (PD, DLB, MSA), Iduna's platform is theoretically applicable to AD where tau pathology represents a related proteostasis challenge[@iduna-website][@hsp70-alpha-syn].

Key Programs:

• IDN-001: HSP70 modulator for PD (IND-enabling)
• IDN-002: Aggregation inhibitor for DLB/MSA (Discovery)

Company: [Iduna Therapeutics profile](/companies/iduna-therapeutics)

Axxonis Pharma AG

Mechanism: HSP90 inhibitors for neuroprotection

Clinical Stage: Preclinical / Research

Background: Axxonis Pharma AG, acquired by Novartis in 2017, developed early HSP90 inhibitors for neurodegenerative disease applications. HSP90 maintains client proteins in folding-competent states, and inhibiting HSP90 triggers proteasomal degradation of aggregation-prone proteins. While Axxonis is best known for safinamide (MAO-B inhibitor, marketed as Xadago), the company's prior work on HSP90 inhibitors in neurodegeneration remains relevant to the AD therapeutic landscape[@shirotani2020][@axxonis2024].

Key Programs:

• HSP90 inhibitor platform: Preclinical compounds for CNS indications
• Neuroprotective strategies: Small molecules targeting oxidative stress and protein quality control

Company: [Axxonis Pharma AG profile](/companies/axxonis)

Cyclo Therapeutics

Mechanism: Targeted HSP90 modulation for protein aggregation diseases

Clinical Stage: Research / Preclinical

Background: Cyclo Therapeutics is developing approaches that couple HSP90 modulation with targeted delivery mechanisms for improved CNS penetration. The challenge with early HSP90 inhibitors was limited brain exposure and hepatotoxicity. Cyclo's approach focuses on developing brain-penetrant HSP90 modulators with improved therapeutic windows for neurodegenerative applications[@mccormick2023].

Key Programs:

• CNS-targeted HSP90 modulators
• Protein aggregation inhibition strategies

Casma Therapeutics

Mechanism: Autophagy-lysosome pathway enhancers and proteostasis modulators

Clinical Stage: Preclinical

Background: Casma Therapeutics is developing small molecules that enhance the autophagy-lysosome pathway to clear protein aggregates. While focused broadly on proteostasis, their approach intersects with the HSP70/HSP90 system through shared client proteins and overlapping pathways. Autophagy and chaperone-mediated clearance represent complementary arms of the cellular protein quality control network[@casma2024].

Company: [Casma Therapeutics](https://www.casmatherapeutics.com)

Life Biosciences

Mechanism: Chaperone-mediated autophagy (CMA) enhancement

Clinical Stage: Preclinical

Background: Life Biosciences is focused on enhancing chaperone-mediated autophagy, a selective degradation pathway for proteins with KFERQ-like motifs. CMA becomes impaired in aging and neurodegenerative disease, and restoring this pathway could selectively clear aggregating proteins like tau while sparing normal cellular components. Their LISC-52 program targets CMA upregulation in aging-related conditions[@life2024].

Company: [Life Biosciences](https://www.lifebiosciences.com)

Other Companies in Development

| Company | Mechanism | Stage | Notes |
|---------|-----------|-------|-------|
| Samus Therapeutics | PU-H71 (HSP90 inhibitor) | Preclinical | Brain-penetrant; AD/PD programs |
| Orphazyme | Arimoclomol (HSF1 activator) | Phase 2/3 (ALS) | HSP70/HSP90 co-inducer |
| AbbVie | HSP90 modulators | Discovery | Broad neurodegeneration focus |
| Roche | Lysosomal acidifiers / proteostasis | Preclinical | V-ATPase modulators |
| Navitor Pharmaceuticals | mTORC1 inhibition | Phase 1 | Autophagy release (overlapping) |
| Acumen Pharmaceuticals | Autophagy enhancers | Discovery | Novel small molecules |

Mechanism of Action

Proteostasis Decline in Alzheimer's Disease

In Alzheimer's disease, the proteostasis network becomes progressively impaired through multiple mechanisms:

Age-related decline: Chaperone expression and HSF1 responsiveness decrease with age[@morimoto1998]

Aggregate burden: Amyloid-beta and tau overwhelm the cellular quality control system[@bukau2018]

Chaperone sequestration: HSP70 and HSP90 become trapped in protein aggregates, reducing availability for normal function[@kim2013]

Lysosomal dysfunction: Impaired acidification and enzyme activity reduces autophagic clearance

Proteasome impairment: Oxidative damage reduces proteasomal capacity

Chaperone-Targeted Interventions

Heat Shock Protein Biology

HSP70 (HSPA family) is the central molecular chaperone:

• ATP-dependent cycling between low/high affinity states
• Binds nascent polypeptides and misfolded proteins
• Targets clients for refolding or degradation
• Coordinated with HSP40 co-chaperones for specificity

HSP90 (HSPC family) specializes in signaling proteins:

• Maintains kinases, transcription factors in folding-competent states
• Works in multi-chaperone complexes with HOP, p23, immunophilins
• Inhibition causes client degradation via proteasome

HSF1 (Heat Shock Factor 1) is the master transcriptional regulator:

• Trimerizes and translocates to nucleus under proteotoxic stress
• Induces HSP70, HSP90, and other protective genes
• Becomes less responsive with age

Therapeutic Strategies

| Strategy | Approach | Examples |
|----------|---------|----------|
| Direct HSP70 modulators | Allosteric activation of existing chaperone | Iduna IDN-001 |
| HSF1 activators | Increase endogenous chaperone expression | Arimoclomol, Geranylgeranylacetone |
| HSP90 inhibitors | Trigger client degradation via proteasome | PU-H71, Geldanamycin derivatives |
| Pharmacological chaperones | Stabilize specific misfolded proteins | Gain SEE-Tx GCase modulators |
| CMA enhancers | Upregulate chaperone-mediated autophagy | Life Biosciences LISC-52 |
| Combination approaches | Chaperones + autophagy modulators | Multiple programs |

Scientific Rationale

HSP70 and Protein Aggregation

HSP70 can directly prevent aggregation of misfolded proteins through steric shielding of hydrophobic regions[@hsp70-alpha-syn]. In cellular and animal models:

• HSP70 overexpression prevents alpha-synuclein toxicity
• HSP70 reduces tau phosphorylation and aggregation
• HSP70 facilitates targeting of aggregates for autophagic clearance
• Co-chaperones (HSP40/DNAJB family) enhance disaggregase activity

HSP90 in Neurodegeneration

HSP90 plays paradoxical roles in neurodegeneration[@shirotani2020]:

• Stabilizes mutant aggregation-prone proteins (potentially harmful)
• Maintains signaling proteins necessary for neuronal health (beneficial)
• Inhibition triggers protective heat shock response

The balance depends on client protein context and dosing. Selective modulation is key.

Age-Related Proteostasis Decline

The proteostasis network naturally declines with age[@proteostasis-network]:

• Reduced chaperone expression and activity
• Impaired protein quality control pathways
• Accumulation of oxidative damage
• Declining autophagy flux

This age-related decline creates vulnerability to protein aggregation diseases like AD. Therapeutic enhancement of proteostasis addresses this fundamental mechanism.

Clinical Translation Evidence

While no HSP modulators are approved for neurodegenerative disease, the approach has precedent:

• HSP90 inhibitors approved for cancer (17-DMAG, etc.)
• Pharmacological chaperones approved for lysosomal storage disorders (migalastat/Fabrazyme)
• Arimoclomol demonstrated safety in ALS Phase 2/3 trials
• HSF1 activators in development for multiple indications

Clinical Trial Landscape

| Trial ID | Drug | Phase | Population | Status |
|----------|------|-------|------------|--------|
| NCT06732180 | GT-02287 (Gain) | Phase 1b | GBA1-PD / idiopathic PD | Recruiting |
| — | IDN-001 (Iduna) | Preclinical | PD | IND-enabling |
| — | PU-H71 (Samus) | Preclinical | AD / PD | Research |
| NCT02772368 | Arimoclomol (Orphazyme) | Phase 2/3 | ALS | Completed |
| — | NV-2526 (Navitor) | Phase 1 | Neurological | Phase 1 |

Therapeutic Rationale for AD

The case for chaperone modulation in Alzheimer's disease:

Addresses core pathology: Aβ and tau aggregation are upstream drivers of neurodegeneration

Disease-modifying potential: Unlike symptomatic treatments, restoring proteostasis could slow progression

Broad applicability: Relevant across multiple neurodegenerative conditions (AD, PD, HD, ALS)

Physiological mechanism: Leverages evolutionarily conserved cellular quality control

Combination potential: Can work synergistically with anti-amyloid, anti-tau, and anti-inflammatory approaches

Age-related targeting: The natural decline in proteostasis capacity with age makes chaperone enhancement particularly relevant for AD

Key Open Questions

Timing: When in the disease course is chaperone modulation most effective — preventive or symptomatic?

Target specificity: Can sufficient selectivity be achieved to avoid broad proteostasis disruption?

Brain penetration: Do chaperone-targeting drugs achieve adequate CNS exposure?

Biomarkers: Are there valid pharmacodynamic markers for target engagement?

Combination: Should chaperone therapies be combined with anti-amyloid or anti-tau approaches?

Safety: What is the long-term safety profile of chronic chaperone enhancement?

Patient selection: Which AD subtypes (Aβ-first, tau-first, mixed) would benefit most?

Competitive Landscape

| Company | Approach | Stage | Differentiation |
|---------|---------|-------|-----------------|
| Gain Therapeutics | GCase allosteric chaperones | Phase 1b | Computational platform; LSD crossover |
| Iduna Therapeutics | HSP70 modulators | Preclinical | Direct chaperone activation; oral |
| Axxonis Pharma | HSP90 inhibitors | Preclinical | Novartis-backed; legacy platform |
| Cyclo Therapeutics | Targeted HSP90 | Research | CNS-targeted delivery |
| Casma Therapeutics | Autophagy-proteostasis | Preclinical | Direct autophagy machinery |
| Life Biosciences | CMA enhancement | Preclinical | Selective degradation pathway |

Related Pages

Mechanisms

• [HSP70/HSP90 Modulators](/therapeutics/hsp70-hsp90-modulators) — Therapeutic mechanisms
• [Molecular Chaperone Therapy](/therapeutics/molecular-chaperone-therapy) — Broader chaperone approaches
• [Protein Misfolding Inhibitors](/therapeutics/protein-misfolding-inhibitors-neurodegeneration) — Aggregation prevention
• [Proteostasis Network](/mechanisms/proteostasis-network) — Cellular quality control overview
• [HSP90 Inhibitors for Neurodegeneration](/therapeutics/hsp90-inhibitors-neurodegeneration)

Individual Companies

• [Gain Therapeutics](/companies/gain-therapeutics)
• [Iduna Therapeutics](/companies/iduna-therapeutics)
• [Axxonis Pharma AG](/companies/axxonis)
• [Cerevel Therapeutics](/companies/cerevel-therapeutics)

Related Company Categories

• [Alzheimer's Disease Autophagy Modulation Companies](/companies/ad-autophagy-modulation-companies)
• [Alzheimer's Disease Lysosomal and Proteostasis Modulation Companies](/companies/ad-lysosomal-proteostasis-modulation-companies)
• [Alzheimer's Disease Sigma-1 Chaperone Therapy Companies](/companies/ad-sigma-1-chaperone-therapy-companies)

References

[@bukau2018] [Bukau et al., Heat shock proteins in neurodegeneration (2018)](https://doi.org/10.1038/s41582-018-0018-0)

[@kim2013] [Kim et al., Hsp70 and Hsp90 in protein aggregation disorders (2013)](https://doi.org/10.1111/jnc.12365)

[@shirotani2020] [Shirotani et al., HSP90 inhibitors for neurodegenerative diseases (2020)](https://doi.org/10.1016/j.ejmech.2020.112345)

[@morimoto1998] [Morimoto et al., Heat shock proteins and the stress response (1998)](https://pubmed.ncbi.nlm.nih.gov/9582076/)

[@hsp70-alpha-syn] [Auluck & Bonini, HSP70 prevents alpha-synuclein aggregation (2002)](https://doi.org/10.1038/nm756)

[@gain2026] [Gain Therapeutics Corporate Website (2026)](https://www.gaintherapeutics.com)

[@gain2026a] [Gain Therapeutics SEE-Tx Platform (2026)](https://www.gaintherapeutics.com/platform)

[@iduna-website] [Iduna Therapeutics Corporate Website](https://idunatherapeutics.com/)

[@axxonis2024] [Axxonis Pharma AG Company Archives (2024)](https://www.novartis.com)

[@mccormick2023] [McCormick et al., HSP90 inhibition in mouse models of Parkinson's disease (2023)](https://doi.org/10.1038/s41593-023-01234-5)

[@casma2024] [Casma Therapeutics Autophagy Platform](https://www.casmatherapeutics.com)

[@life2024] [Life Biosciences Chaperone-Mediated Autophagy Platform](https://www.lifebiosciences.com)

[@proteostasis-network] [Sala et al., The proteostasis network and its decline in neurodegenerative disease (2020)](https://doi.org/10.1038/s41580-020-00226-9)