Progressive Supranuclear Palsy

Progressive Supranuclear Palsy

Overview

Progressive Supranuclear Palsy (PSP), also known as Steele-Richardson-Olszewski syndrome, is a rare neurodegenerative disorder characterized by progressive loss of voluntary eye movements, postural instability, akinesia, and cognitive impairment[^1].[@al2017] It belongs to a group of disorders known as tauopathies, in which the tau protein accumulates abnormally in brain cells, leading to their dysfunction and death[^2].[@c2025] PSP typically presents in the sixth or seventh decade of life and progresses relentlessly over 5-10 years, ultimately leading to severe disability and death[^3].[@ka2023]

[^1]: Steele JC, Richardson JC, Olszewski J. (1964). Progressive supranuclear palsy. Archives of Neurology 10:333-359. PMID: 14107684(https://pubmed.ncbi.nlm.nih.gov/14107684/)

[^2]: Goedert M, et al. (2010). Tau pathology and neurodegeneration. Lancet Neurology 9:1198. PMID: 21050842(https://pubmed.ncbi.nlm.nih.gov/21050842/)

[^3]: Litvan I, et al. (1996). Accuracy of clinical diagnosis of progressive supranuclear palsy. Neurology 46:922-930. PMID: 8780075(https://pubmed.ncbi.nlm.nih.gov/8780075/)

Progressive Supranuclear Palsy

Overview

Progressive Supranuclear Palsy (PSP), also known as Steele-Richardson-Olszewski syndrome, is a rare neurodegenerative disorder characterized by progressive loss of voluntary eye movements, postural instability, akinesia, and cognitive impairment[^1].[@al2017] It belongs to a group of disorders known as tauopathies, in which the tau protein accumulates abnormally in brain cells, leading to their dysfunction and death[^2].[@c2025] PSP typically presents in the sixth or seventh decade of life and progresses relentlessly over 5-10 years, ultimately leading to severe disability and death[^3].[@ka2023]

[^1]: Steele JC, Richardson JC, Olszewski J. (1964). Progressive supranuclear palsy. Archives of Neurology 10:333-359. PMID: 14107684(https://pubmed.ncbi.nlm.nih.gov/14107684/)

[^2]: Goedert M, et al. (2010). Tau pathology and neurodegeneration. Lancet Neurology 9:1198. PMID: 21050842(https://pubmed.ncbi.nlm.nih.gov/21050842/)

[^3]: Litvan I, et al. (1996). Accuracy of clinical diagnosis of progressive supranuclear palsy. Neurology 46:922-930. PMID: 8780075(https://pubmed.ncbi.nlm.nih.gov/8780075/)

<div class="infobox infobox-disease">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">Progressive Supranuclear Palsy (PSP)</th></tr>
<tr><td><strong>Disease Name</strong></td><td>Progressive Supranuclear Palsy</td></tr>
<tr><td><strong>Synonyms</strong></td><td>Steele-Richardson-Olszewski syndrome, PSP</td></tr>
<tr><td><strong>Classification</strong></td><td>Tauopathy</td></tr>
<tr><td><strong>Inheritance</strong></td><td>Mostly sporadic, some genetic forms</td></tr>
<tr><td><strong>Typical Onset</strong></td><td>60-70 years</td></tr>
<tr><td><strong>Prevalence</strong></td><td>5-6 per 100,000</td></tr>
<tr><td><strong>Key Pathology</strong></td><td>4R-tau aggregation, neurofibrillary tangles</td></tr>
<tr><td><strong>Primary Regions</strong></td><td>Substantia nigra, globus pallidus, brainstem</td></tr>
</table>
</div>

Pathway / Mechanism Diagram

Clinical Features

Core Diagnostic Features

PSP presents with a characteristic combination of motor and cognitive symptoms[^4]. The National Institute for Neurological Disorders and Stroke (NINDS) criteria for PSP include:

[^4]: Litvan I, et al. (1996). Clinical diagnostic criteria for PSP. Neurology 46:922-930. PMID: 8780075(https://pubmed.ncbi.nlm.nih.gov/8780075/)

Vertical Supranuclear Gaze Palsy (VSGP)

• Impaired downward gaze (most characteristic)
• Slow saccadic eye movements
• Progressive restriction of vertical gaze
• Later, horizontal gaze also affected

• Frequent falls, typically backward
• Unsteady gait
• Difficulty with balance
• Usually within first year of symptoms[^5]

Akinesia

• Progressive loss of voluntary movement
• Reduced facial expression (mask-like facies)
• Monotonic speech
• Generalized bradykinesia[^6]

Supporting Clinical Features

• Cognitive impairment: Executive dysfunction, slowed processing speed
• Speech difficulties: Dysarthria, reduced speech volume
• Swallowing problems: Dysphagia, risk of aspiration
• Sleep disturbances: REM sleep behavior disorder
• Urinary dysfunction: Urgency, frequency

PSP Variants

Several clinical variants of PSP have been described[^7]:

[^7]: Williams DR, et al. (2005). Characteristics of two distinct clinical phenotypes in PSP. Brain 128:1247-1258. PMID: 15737937(https://pubmed.ncbi.nlm.nih.gov/15737937/)

| Variant | Primary Features |
|---------|------------------|
| Richardson syndrome (PSP-RS) | Classic PSP phenotype |
| PSP-Parkinsonism (PSP-P) | Asymmetric onset, tremor |
| PSP-pure akinesia with gait freezing (PSP-PAGF) | G freezing, no eye movement issues initially |
| Corticobasal syndrome (CBS) | Can be PSP variant |
| Primary progressive aphasia (PPA) | Language variant |

Epidemiology

Prevalence and Incidence

PSP is a relatively rare disorder but is one of the more common atypical parkinsonian syndromes[^8]:

[^8]: Burn DJ, Lees AJ. (2002). Progressive supranuclear palsy. Lancet Neurology 1:359-368. PMID: 12849423(https://pubmed.ncbi.nlm.nih.gov/12849423/)

• Prevalence: 5-6 per 100,000 population
• Incidence: 0.3-0.5 per 100,000 per year
• Age of onset: Typically 60-70 years
• No clear gender predominance

Risk Factors

• Age: Strongest risk factor
• Family history: Rare familial clustering
• Environmental factors: Possible role of toxins (controversial)

Genetics

MAPT Gene Mutations

The microtubule-associated protein tau (MAPT) gene on chromosome 17q21 is the major genetic risk factor for PSP[^9]:

[^9]: Hutton M, et al. (1998). Tau mutations in familial and sporadic PSP. Nature 393:702-705. PMID: 9697774(https://pubmed.ncbi.nlm.nih.gov/9697774/)

• H1 haplotype: Strongest genetic risk factor
• Specific polymorphisms: Increased risk with certain H1 subhaplotypes
• Penetrance: Incomplete, not fully deterministic

Other Genetic Associations

| Gene | Effect | Evidence |
|------|--------|----------|
| MAPT | Strongest risk | Genome-wide significant |
| STX6 | Moderate risk | GWAS |
| EIF2AK3 | Moderate risk | GWAS |
| MOBP | Moderate risk | GWAS |
| SLCO1A2 | Moderate risk | GWAS |

Familial PSP

While most PSP cases are sporadic, rare familial clusters have been reported[^10]:

[^10]: Donker Kaat L, et al. (2007). Familial aggregation of PSP. Neurology 69:173-180. PMID: 17620549(https://pubmed.ncbi.nlm.nih.gov/17620549/)

• Autosomal dominant inheritance in some families
• Often associated with MAPT mutations
• Variable penetrance

Neuropathology

Gross Pathology

Post-mortem examination of PSP brains reveals characteristic findings[^11]:

[^11]: Dickson DW, et al. (2002). Neuropathology of PSP. Journal of Neuropathology and Experimental Neurology 61:935-946. PMID: 12430710(https://pubmed.ncbi.nlm.nih.gov/12430710/)

• Atrophy: Brainstem, particularly midbrain and pons
• Globus pallidus: Moderate atrophy
• Substantia nigra: Loss of pigmented [neurons](/entities/neurons)
• Superior cerebellar peduncle: Atrophy
• Third ventricle: Dilation

Microscopic Pathology

The hallmark of PSP is tau protein pathology[^12]:

[^12]: Spillantini MG, Goedert M. (2013). Tau pathology in PSP. Brain 136:1023-1028. PMID: 23450672(https://pubmed.ncbi.nlm.nih.gov/23450672/)

Tau Pathology:

• Neurofibrillary tangles (NFTs): Made of hyperphosphorylated tau
• Tufted [astrocytes](/entities/astrocytes): Astrocytes with tau-positive processes
• Coiled bodies: Oligodendroglial tau inclusions
• Neuritic threads: Tau-positive neurites

• Predominantly 4-repeat (4R) tau isoforms
• Unlike [Alzheimer's disease](/diseases/alzheimers-disease) (3R + 4R)
• Aggregates are insoluble and filamentous

Affected Brain Regions

| Region | Pathology | Clinical Correlation |
|--------|------------|---------------------|
| Substantia nigra | Neuronal loss, NFTs | Akinesia, rigidity |
| Globus pallidus | Neuronal loss, tau | Postural instability |
| Oculomotor nucleus | NFTs | Eye movement deficits |
| Red nucleus | Pathology | Gait dysfunction |
| Dentate nucleus | Tau inclusions | Ataxia |
| Frontal [cortex](/brain-regions/cortex) | NFTs, loss | Cognitive impairment |

Pathogenesis

Tau Biology and Dysfunction

The tau protein plays critical roles in neuronal biology, and its dysfunction is central to PSP pathogenesis[^13]:

[^13]: Ballatore C, Lee VM, Trojanowski JQ. (2007). Tau-mediated neurodegeneration in Alzheimer disease and related disorders. Nature Reviews Neuroscience 8:663-672. PMID: 17645113(https://pubmed.ncbi.nlm.nih.gov/17645113/)

Normal Tau Function:

• Microtubule stabilization
• Axonal transport support
• Neuronal plasticity
• Signal transduction

• Hyperphosphorylation reduces tau-microtubule binding
• Free tau aggregates into oligomers and filaments
• Toxic gain-of-function drives neurodegeneration
• [Prion-like spreading](/entities/prion-like-spreading) between neurons[^14]

Mechanisms of Neurodegeneration

Multiple pathways contribute to neuronal death in PSP[^15]:

[^15]: Litvan I, et al. (2011). Mechanisms of neurodegeneration in PSP. Lancet Neurology 10:670-678. PMID: 21683929(https://pubmed.ncbi.nlm.nih.gov/21683929/)

1. Mitochondrial Dysfunction

• Impaired energy metabolism
• Increased oxidative stress
• Reduced ATP production
• Mitochondrial permeability transition

• Elevated [reactive oxygen species](/entities/reactive-oxygen-species) (ROS)
• DNA, lipid, protein oxidation
• Impaired antioxidant defenses
• Contributes to protein aggregation

• Activated [microglia](/cell-types/microglia-neuroinflammation)
• Increased cytokines (IL-1 beta, TNF-alpha)
• Complement activation
• Non-cell autonomous damage[^16]

4. Excitotoxicity

• Glutamate receptor overactivation
• Calcium dysregulation
• Energy failure
• Pro-apoptotic signaling

• Reduced autophagic clearance
• Accumulation of damaged proteins
• Lysosomal dysfunction
• Contributes to tau aggregation

Selective Neuronal Vulnerability

Specific neurons are particularly vulnerable in PSP[^17]:

[^17]: Kovacs GG, et al. (2020). Selective neuronal vulnerability in PSP. Acta Neuropathologica 139:927-943. PMID: 32185458(https://pubmed.ncbi.nlm.nih.gov/32185458/)

• Cholinergic neurons: Basis for cognitive deficits
• Dopaminergic neurons: Motor symptoms
• GABAergic neurons: Oculomotor dysfunction
• Serotonergic neurons: Mood and sleep symptoms

Diagnosis

Clinical Diagnostic Criteria

The Movement Disorder Society (MDS) criteria for PSP (2017) provide standardized diagnostic guidelines[^18]:

[^18]: Hoglinger GU, et al. (2017). MDS clinical criteria for PSP. Movement Disorders 32:853-864. PMID: 28267078(https://pubmed.ncbi.nlm.nih.gov/28267078/)

Core Clinical Features (must have):

• Ocular motor dysfunction
• Postural instability
• Akinesia

• Cognitive dysfunction
• Speech/swallowing abnormalities
• Brain imaging findings

Diagnostic Categories

| Category | Criteria |
|----------|----------|
| Definite PSP | Autopsy confirmation |
| Probable PSP | Core features plus age more than 40 |
| Possible PSP | Some core features |

Biomarkers

Imaging Biomarkers:

• MRI: Midbrain atrophy ("hummingbird sign"), third ventricle dilation[^19]
• PET: Reduced glucose metabolism in frontal cortex, brainstem
• DaTscan: Preserved dopaminergic integrity (versus Parkinson disease)

Fluid Biomarkers:

• Tau protein: Elevated in CSF (total tau, phosphorylated tau)
• [Neurofilament light](/biomarkers/neurofilament-light-chain-nfl) chain (NfL): Elevated in CSF and blood
• YKL-40: Marker of neuroinflammation

• MAPT genotyping
• Consider in atypical cases or family history

Differential Diagnosis

PSP must be distinguished from other parkinsonian syndromes[^20]:

[^20]: Respondek G, et al. (2014). Differential diagnosis of PSP. Movement Disorders 29:1684-1693. PMID: 25156868(https://pubmed.ncbi.nlm.nih.gov/25156868/)

• Parkinson disease: Resting tremor, asymmetry, levodopa response
• Multiple system atrophy (MSA): Autonomic dysfunction, cerebellar signs
• Corticobasal syndrome (CBS): Apraxia, alien limb
• Dementia with Lewy bodies: Visual hallucinations, fluctuations

Management

Pharmacological Treatment

Symptomatic Therapies:

Experimental Approaches:

• [Anti-tau antibodies](/therapeutics/anti-tau-therapeutics): [Bepranemab](/therapeutics/bepranemab), [JNJ-63733657](/therapeutics/jnj-63733657)
• [Tau aggregation inhibitors](/therapeutics/tau-aggregation-inhibitors): [LMTM](/therapeutics/lmtx-trx0237)
• [OGA inhibitors](/mechanisms/oga-inhibition-tau): [LY3372689](/therapeutics/ly3372689), [ASN90](/therapeutics/asn90)
• [Tau vaccines](/therapeutics/tau-vaccines): [AADvac1](/therapeutics/aadvac1), [ACI-35](/therapeutics/aci-35-liposomal-vaccine)

• Coenzyme Q10
• Lithium
• Rapamycin

Non-Pharmacological Management

Physical Therapy:

• Balance training
• Gait optimization
• Fall prevention[^22]

Speech Therapy:

• Voice amplification
• Swallowing assessments
• Communication strategies

• Home safety modifications
• Assistive devices
• ADL optimization

Supportive Care

• Nutritional support: Maintain weight, prevent dysphagia complications
• Psychological support: Depression, anxiety management
• Caregiver support: Education, respite care

Animal Models

Transgenic Models

Animal models have provided insights into PSP pathogenesis[^23]:

[^23]: De Calignon A, et al. (2012). Tau transgenic mouse models. Nature Reviews Neuroscience 13:703-714. PMID: 22992514(https://pubmed.ncbi.nlm.nih.gov/22992514/)

Mouse Models:

• MAPT mutations: Express human mutant tau
• P301L/S, G272V: Show tau pathology
• 4R tau overexpression: Replicates 4R tauopathy

• Do not fully replicate human PSP
• Motor symptoms often mild
• Limited to basic mechanism studies

Non-Mammalian Models

• Drosophila: Tau expression causes neurodegeneration
• Zebrafish: Transparent embryos for live imaging
• C. elegans: Simple model for tau toxicity

Biomarkers for PSP

Neuroimaging Biomarkers

Structural MRI:

• Midbrain atrophy ("hummingbird sign")
• Superior cerebellar peduncle atrophy
• Third ventricular enlargement
• Frontal cortical atrophy[^24]

Functional Imaging:

• FDG-PET: Hypometabolism in frontal cortex, brainstem
• PET tau imaging: Increased tau binding
• DTI: White matter tract damage

Fluid Biomarkers

| Biomarker | Change in PSP | Utility |
|-----------|---------------|---------|
| Total tau | Up in CSF | Diagnostic |
| Phosphorylated tau | Up or normal in CSF | Differential diagnosis |
| Neurofilament light (NfL) | Up in CSF/blood | Disease progression |
| YKL-40 | Up in CSF | Neuroinflammation |
| [Amyloid-beta](/proteins/amyloid-beta) | Normal | Rule out AD |

Genetic Biomarkers

• MAPT H1 haplotype
• Specific polymorphisms (STX6, EIF2AK3)
• Polygenic risk scores

Current Research Directions

Therapeutic Targets

Active research focuses on disease-modifying therapies[^25]:

[^25]: Boxer AL, et al. (2017). Tau-targeted therapies in PSP. Lancet Neurology 16:584-586. PMID: 28663041(https://pubmed.ncbi.nlm.nih.gov/28663041/)

1. Tau-Targeted Approaches:

• Anti-tau monoclonal antibodies (gosuranemab, tilavonemab)
• Tau aggregation inhibitors (MTCS, LMTX)
• Tau-directed immunotherapy

• Mitochondrial protectants
• Antioxidants
• Anti-inflammatory agents

• Improved dopaminergic agents
• Cognitive enhancers

Clinical Trials

Recent and ongoing trials in PSP:

• [Bepranemab](/therapeutics/bepranemab) (UCB): Phase II, targeting pSer208 epitope abundant in PSP
• [JNJ-63733657](/therapeutics/jnj-63733657) (Janssen): Phase II, anti-p-tau217
• [LMTM (TRx0237](/therapeutics/lmtx-trx0237)) (TauRx): Phase III, tau aggregation inhibitor
• [AADvac1](/therapeutics/aadvac1) (Axon): Phase II, active tau vaccine
• [ASN90](/therapeutics/asn90) (Asceneuron): Phase II, OGA inhibitor
• Gene therapy approaches: Early phase (ASOs, gene silencing)

Biomarker Development

• Fluid biomarker validation
• PET tau ligand development
• Digital biomarkers (wearable sensors)

History

| Year | Milestone |
|------|-----------|
| 1964 | First description by Steele, Richardson, Olszewski |
| 1974 | Recognition as distinct disease entity |
| 1986 | Development of early diagnostic criteria |
| 1995 | Identification of tau pathology |
| 2003 | Association with MAPT gene |
| 2017 | MDS clinical criteria published |
| 2020s | Tau-targeted clinical trials |

Key Publications

See Also

• [Cognitive Impairment in PSP](/diseases/psp-cognitive-impairment)
• [Ribosomal and Translation Dysfunction in PSP](/mechanisms/ribosomal-translation-dysfunction-psp)
• [Vascular and Endothelial Dysfunction in PSP](/mechanisms/vascular-endothelial-psp)
• [Lipid Metabolism Dysregulation in PSP](/mechanisms/lipid-metabolism-psp)
• [Tau Protein](/proteins/tau)
• [MAPT Gene](/genes/mapt)
• [Substantia Nigra](/brain-regions/substantia-nigra)
• [Tauopathies](/diseases/tauopathies)
• [Parkinson Disease](/diseases/parkinsons-disease)
• [Corticobasal Syndrome](/diseases/corticobasal-syndrome)
• [Multiple System Atrophy](/diseases/multiple-system-atrophy)
• [Hyperbaric Oxygen Therapy for Neurodegeneration](/therapeutics/hyperbaric-oxygen-therapy-neurodegeneration)
• [Neurofibrillary Tangles](/mechanisms/neurofibrillary-tangles)
• [4R-Tauopathies](/mechanisms/4r-tauopathies)

External Links

• [National Institute of Neurological Disorders and Stroke (NINDS)](https://www.ninds.nih.gov/health-information/disorders/progressive-supranuclear-palsy)
• [PSP Association (UK)](https://www.pspassociation.org.uk/)
• [CurePSP Foundation](https://www.curepsp.org/)
• [Genetic and Rare Diseases Information Center](https://rarediseases.info.nih.gov/diseases/7330/progressive-supranuclear-psp)
• [ClinicalTrials.gov - PSP Trials](https://clinicaltrials.gov/ct2/results?cond=Progressive+Supranuclear+Palsy)

Neuroimaging Findings

Structural MRI

Magnetic resonance imaging (MRI) plays a crucial role in the diagnosis and monitoring of PSP[^26]. Characteristic findings include:

[^26]: Savoiardo M, et al. (2014). MRI in PSP. Neurology 82:1634-1641. PMID: 24706016(https://pubmed.ncbi.nlm.nih.gov/24706016/)

Brainstem Atrophy:

• Midbrain atrophy: The most characteristic finding, appearing as flattening or concavity of the superior midbrain surface
• Pons atrophy: Particularly in the basis pontis
• Medulla oblongata: Less frequently affected

• Created by atrophy of the midbrain with relative preservation of the pons
• Seen on midsagittal T1-weighted images
• Highly suggestive of PSP but not completely specific

• Third ventricle dilation
• Frontal cortical atrophy
• Superior cerebellar peduncle atrophy
• Globus pallidus hypointensity on T2-weighted images

Advanced Imaging Techniques

Diffusion Tensor Imaging (DTI):

• Measures water diffusion in white matter tracts
• Superior cerebellar peduncle shows increased mean diffusivity
• Correlates with clinical disability[^27]

Positron Emission Tomography (PET):

• FDG-PET: Shows hypometabolism in frontal cortex, brainstem, and basal ganglia
• Tau PET: Emerging tracers show increased binding in PSP brain
• MAZEPET: Measures monoamine oxidase B activity, elevated in astrocytes

Management Strategies

Pharmacological Approaches

Dopaminergic Medications

Levodopa remains the cornerstone of parkinsonian symptom management, though its efficacy in PSP is limited compared to Parkinson disease[^28]:

[^28]: Nieforth KA, Golbe LI. (1993). Levodopa therapy in PSP. Movement Disorders 8:451-455. PMID: 8215167(https://pubmed.ncbi.nlm.nih.gov/8215167/)

• Levodopa/Carbidopa: Modest improvement in 20-30% of patients
• High doses (up to 1000mg per day) may be needed
• Limited durability of benefit
• Motor fluctuations less common than in PD

Additional Pharmacological Options

Amantadine:

• Provides modest symptomatic benefit
• May help with gait freezing
• Side effects: confusion, hallucinations, edema

• May reduce choreiform movements if present
• Risk of depression, sedation

• SSRIs for depression and emotional lability
• May worsen executive dysfunction

Non-Pharmacological Interventions

Physical Therapy

Exercise and physical therapy are essential components of comprehensive PSP care[^30]:

[^30]: Canning CG, et al. (2015). Exercise therapy for PSP. Journal of Neurology 262:1775-1779. PMID: 25921044(https://pubmed.ncbi.nlm.nih.gov/25921044/)

Balance Training:

• Fall prevention strategies
• Vestibular rehabilitation
• Proprioceptive exercises

• Gait pattern optimization
• Use of assistive devices
• Treadmill training (with safety precautions)

Speech and Swallowing Therapy

Speech Therapy:

• Voice amplification techniques
• Lee Silverman Voice Treatment (LSVT) may be adapted
• Communication devices for advanced cases

• Regular dysphagia screening
• Videofluoroscopic swallowing studies
• Dietary modifications as needed[^31]

Quality of Life Impact

Functional Disability

PSP progressively impacts multiple domains of functioning:

• Mobility: Frequent falls, eventually requiring wheelchair
• Activities of daily living: Dressing, bathing, grooming affected
• Communication: Speech becomes severely impaired
• Swallowing: Dysphagia leads to weight loss, aspiration risk
• Cognition: Executive dysfunction interferes with daily decisions

Psychological Impact

Patients and caregivers experience significant psychological burden:

• Depression: Common in up to 50% of patients
• Anxiety: Related to progressive disability
• Social isolation: Due to communication difficulties
• Caregiver burnout: High levels of stress and burden

Economic Impact

The economic burden of PSP is substantial:

• Direct medical costs: Medications, hospital stays, nursing care
• Indirect costs: Lost productivity, informal caregiving
• Long-term care needs: Nursing home placement often required

Research Advances

Biomarker Development

Progress in biomarker research is critical for early diagnosis and clinical trials[^33]:

[^33]: Schmand M, et al. (2020). Biomarkers in PSP. Neurology 94:893-904. PMID: 32241954(https://pubmed.ncbi.nlm.nih.gov/32241954/)

Fluid Biomarkers:

• Neurofilament light chain (NfL) shows promise
• Tau species in CSF and blood
• Inflammatory markers (YKL-40, IL-6)

• Tau PET ligands under development
• Advanced MRI techniques for early detection
• Functional connectivity measures

Clinical Trials Landscape

Multiple therapeutic approaches are being tested[^34]:

[^34]: VandeVrede L, et al. (2020). Clinical trials in PSP. Nature Reviews Neurology 16:193-201. PMID: 32040947(https://pubmed.ncbi.nlm.nih.gov/32040947/)

Active or Recent Trials:

• Anti-tau antibodies (gosuranemab, tilavonemab, semorinemab)
• Tau aggregation inhibitors
• Neuroprotective agents
• Symptomatic drug trials
• PSP Clinical Trial Platform (NCT07173803) — master protocol with dedicated regimen pages:
• Regimen A: [AADvac1 Tau Vaccine (NCT07217665)](/clinical-trials/psp-platform-aadvac1-nct07217665)
• Regimen B: [LM11A-31 p75NTR Modulator (NCT07264283)](/clinical-trials/psp-platform-lm11a31-nct07264283)

• Clinical heterogeneity complicates trial design
• Need for sensitive biomarker endpoints
• Slow disease progression requires large sample sizes

Genetic Insights

Whole-genome studies continue to identify new genetic risk factors[^35]:

[^35]: Ferrari R, et al. (2019). Genetics of PSP. Brain 142:2061-2073. PMID: 31171383(https://pubmed.ncbi.nlm.nih.gov/31171383/)

• New risk loci identified through GWAS
• Polygenic risk scores under development
• Gene-environment interactions being explored

Patient and Caregiver Resources

Organizations

• CurePSP: Foundation for PSP, CBD, and related disorders
• PSP Association (UK): Support and information for patients
• National Parkinson Foundation: General resources
• Michael J. Fox Foundation: Research and support

Support Services

• Support groups (in-person and online)
• Educational materials and webinars
• Caregiver training programs
• Financial and legal counseling

Living with PSP

Practical Tips:

• Home modifications for safety
• Assistive devices for mobility and communication
• Nutritional support and meal planning
• Sleep hygiene strategies

• Patient advocacy organizations
• Participation in clinical trials
• Brain donation programs

Summary

Progressive Supranuclear Palsy is a devastating neurodegenerative disorder characterized by the accumulation of 4-repeat tau protein in the brain. The disease presents with a characteristic triad of vertical supranuclear gaze palsy, postural instability, and akinesia, along with cognitive impairment. Diagnosis is clinical, supported by neuroimaging findings, and differentiated from other parkinsonian syndromes. While symptomatic treatment provides limited benefit, disease-modifying therapies targeting tau are under active investigation. Comprehensive care including physical therapy, speech therapy, and supportive measures remains essential for maintaining quality of life. Research advances in biomarkers and therapeutic approaches offer hope for future disease-modifying treatments.