Glossary of key terms in PSP

Grasping PSP's intricacies hinges on understanding key definitions and concepts. Familiarity with these principles will help you navigate its complexities.

p-tau217

p-tau217 is a phosphorylated form of the tau protein at threonine residue 217, and it serves as a highly specific and sensitive biomarker for Alzheimer's disease (AD) pathology. Measurement of p-tau 217 in plasma or cerebrospinal fluid (CSF) reflects abnormal tau phosphorylation associated with neurofibrillary tangle formation. Compared to other phosphorylated tau isoforms (such as p-tau181), p-tau 217 demonstrates superior diagnostic accuracy for distinguishing AD from non-AD neurodegenerative disorders, including progressive supranuclear palsy (PSP).

[60]

Parkinsonism

Clinical syndrome characterized by bradykinesia plus rigidity, tremor, or postural instability.

[5]

Patient journey

The sequence of patients’ experiences and perspectives through stages of care - from symptom onset to diagnosis, treatment, and ongoing disease management.

[61]

PET scan

An imaging technique using positron emission tomography (PET) to visualize and measure metabolic or molecular activity in tissues, often applied in neurology to assess brain function or pathology. 

[62]

Pharmacodynamics (PD)

The biological and physiological effects of drugs on the body, including the mechanism of action at the target site. (It answers the question: "What does the drug do to the body?").

[3]

Pharmacokinetic profile (PK)

The characterization of how a drug is absorbed, distributed, metabolized, and eliminated by the body over time. (It answers the question: "What does the body do to the drug?).

[9]

Phase 1 study

The first stage of clinical research in humans, primarily assessing a drug’s safety in a small group of healthy volunteers or patients.

[3]

Phase 2 study

The second stage of a clinical trial aimed to evaluate a drug’s efficacy and short-term safety in patients.

[3]

Phase 3 study

The last stage of a clinical trial before licensing. A large-scale clinical trial designed to confirm a drug’s efficacy and safety to support regulatory approval.

[3]

Phenotype

The set of observable characteristics (symptoms, clinical signs) that define different forms of a disease. In PSP, several variants have been described: PSP-RS, PSP-P, PSP-PGF, PSP-CBS, PSP-SL, PSP-PI, PSP-OM, PSP-F, PSP-C, PSP-PLS.

[5]

Phosphorylation

A post-translational modification in which a phosphate group is added to a protein or other molecule, regulating its activity, function, or signaling properties.

[42]

Photophobia

Extreme sensitivity to light.

[5]

Placebo

An inactive substance designed to resemble the experimental treatment, used as a control to measure the true effect of the active drug.

[3]

Placebo-controlled

Trial design in which the effects of an active treatment are compared with those of an inactive substance (placebo) to assess the true efficacy of the intervention.

[3]

Post-translational modifications (PTMs)

Chemical or structural changes made to proteins after their synthesis, altering their function, stability, or interactions.

[63]

Postsynaptic striatal dopaminergic degeneration

Loss or dysfunction of dopamine-receiving neurons in the striatum, leading to impaired motor signaling.

[5]

Preclinical

Research conducted before testing in humans, using laboratory and animal studies to evaluate the pharmacological, toxicological, and pharmacokinetic properties of a drug.

[64]

Presymptomatic

Stage where the disease is already present in the brain, but no symptoms are visible yet.

[8]

Prevalence

The total number of cases of a disease in a population at a specific point in time or over a defined period.

[65]

Prion-like propagation

Process in which abnormal proteins (e.g., NFTs) spread from cell to cell, converting healthy proteins into the same harmful form and spreading the disease throughout the brain.

[66]

Prognosis

The predicted outcome of a disease, including likelihood of recovery or recurrence.

[67]

Progressive (disease)

A disease that worsens over time in terms of extent or severity.

[68]

PROSPER

PROSPER is an ongoing multinational, randomised, double-blind, placebo-controlled Phase 2 study to assess the safety, tolerability and efficacy of FNP-223 administered orally at a dose of 300 mg three times a day in adults aged 50–80 years with early-stage possible or probable PSP-RS.

[30]

Protein aggregation

Process in which misfolded proteins clump together, forming toxic deposits in the brain, like tau in tauopathies.

[48]

Referenties

  1. EU Clinical Trials Register. Glossary [Internet]. [cited 2025 Nov]. Available from: https://www.clinicaltrialsregister.eu/doc/EU_Clinical_Trials_Register_Glossary.pdf

  2. Höglinger GU, Respondek G, Stamelou M, et al. Clinical diagnosis of progressive supranuclear palsy: the movement disorder society criteria. Mov Disord. 2017;32(6):853-864. doi:10.1002/mds.26987

  3. Boxer AL, Yu JT, Golbe LI, Litvan I, Lang AE, Höglinger GU. Advances in progressive supranuclear palsy: new diagnostic criteria, biomarkers, and therapeutic approaches. Lancet Neurol. 2017;16(7):552-563. doi:10.1016/S1474-4422(17)30157-6

  4. Grogan S, Preuss CV. Pharmacokinetics. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 [cited 2025 Nov]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557744/

  5. ClinicalTrials.gov. PROSPER (NCT06355531) [Internet]. [cited 2025 Nov]. Available from: https://clinicaltrials.gov/study/NCT06355531

  6. Tapia-Rojas C, Cabezas-Opazo F, Deaton CA, Vergara EH, Johnson GVW, Quintanilla RA. It's all about tau. Prog Neurobiol. 2019;175:54-76. doi:10.1016/j.pneurobio.2018.12.005

  7. Zhang Y, Wu KM, Yang L, Dong Q, Yu JT. Tauopathies: new perspectives and challenges. Mol Neurodegener. 2022;17(1):28. doi:10.1186/s13024-022-00533-z

  8. Leuzy A, Janelidze S, Mattsson-Carlgren N, et al. Comparing the clinical utility and diagnostic performance of CSF P-Tau181, P-Tau217, and P-Tau231 assays. Neurology. 2021;97(17):e1681-e1694. doi:10.1212/WNL.0000000000012727

  9. Respondek G, Breslow D, Amirghiasvand C, et al. The lived experiences of people with progressive supranuclear palsy and their caregivers. Neurol Ther. 2023;12(1):229-247. doi:10.1007/s40120-022-00420-1

  10. ScienceDirect Topics. PET scanner [Internet]. [cited 2025 Nov]. Available from: https://www.sciencedirect.com/topics/nursing-and-health-professions/pet-scanner

  11. ScienceDirect Topics. Post-translational modification [Internet]. [cited 2025 Nov]. Available from: https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/posttranslational-modification

  12. ScienceDirect Topics. Preclinical study [Internet]. [cited 2025 Nov]. Available from: https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/preclinical-study

  13. ScienceDirect Topics. Prevalence [Internet]. [cited 2025 Nov]. Available from: https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/prevalence

  14. Kammula SV, Tripathi S, Wang N, et al. Unraveling the tau puzzle: a review of mechanistic targets and therapeutic interventions to prevent tau pathology in Alzheimer’s disease. Ageing Neur Dis. 2023;3(4). doi:10.20517/and.2023.20

  15. ScienceDirect Topics. Prognosis [Internet]. [cited 2025 Nov]. Available from: https://www.sciencedirect.com/topics/nursing-and-health-professions/prognosis

  16. National Center for Biotechnology Information (NCBI). MedGen: Progressive disease [Internet]. [cited 2025 Nov]. Available from: https://www.ncbi.nlm.nih.gov/medgen/277534