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Comprehensive Glossary of Terms

Comprehensive Glossary of NPC and ASMD Terms


2-hydroxypropyl-β-cyclodextrin -
A specific type of cyclodextrin molecule used experimentally in NPC treatment; also known as HP-β-CD, helps remove trapped cholesterol from cells. Two forms used in clinical trials in NPC are Trappsol Cyclo and Adrabetadex

Acid Sphingomyelinase Deficiency (ASMD) - A rare genetic disorder caused by deficiency of the enzyme acid sphingomyelinase, leading to accumulation of sphingomyelin in cells. This name is now used to represent the spectrum disorder previously known as Niemann Pick type A and Niemann Pick type B.

Adrabetadex – Name for a specific HP-β-CD (2-hydroxypropyl-β-cyclodextrin) currently being studied and under development for NPC

Aqneursa – Brand name for levacetylleucine approved by the FDA to treat the neurological symptoms in NPC

Arimoclomol - Generic name for Miplyffa

Ataxia - Loss of coordination and balance; a common neurological symptom that affects walking, speech, and fine motor skills

Autosomal Recessive - A pattern of genetic inheritance where a person must inherit two copies of a defective gene (one from each parent) to develop the condition; this is how NPC and ASMD are inherited

Azafaros – A biopharmaceutical company developing nizubaglustat.

Biologic - A type of drug made from living organisms or their cellular components such as altered proteins, antibodies, genes or DNA; different from traditional chemical drugs. Xenpozyme (olipudase alfa) is an example of a biologic

Biological Activity - Measurable effects that a drug has on the body’s biological processes

Biomarker - Biomarkers serve as objective signs that can be detected and measured outside of the patient’s subjective experience. A biomarker can be a measurable biological indicator found in blood, other body fluids, or tissues that can signal normal biological processes, disease states, or responses to treatment. Other examples of biomarkers include MRIs and data obtained from digital health technology

Body Surface Area (BSA) - A measurement used to calculate appropriate drug doses, especially in pediatric patients

Capsules - The oral dosage form for medications like Miplyffa and miglustat

Carrier - A person who has one copy of a gene mutation for an autosomal recessive condition like NPC; carriers typically don’t have symptoms but can pass the mutation to their children

Case-Control study - A type of observational study that compares people with a disease (cases) to people without the disease (controls) to identify factors that may contribute to the condition

Cataplexy - Sudden loss of muscle tone triggered by strong emotions; a neurologic symptom that can occur in some NPC patients

Cell (Plasma) Membrane - The outer boundary of cells that controls what enters and exits; can be affected by the abnormal cholesterol accumulation in NPC

Cell Trafficking - The process by which cells transport materials and organelles within themselves and between different cellular compartments; disrupted in NPC due to cholesterol accumulation

Cellular Activity - The various processes that occur within cells, including energy production and signaling

Ceramide Glucosyltransferase - An enzyme involved in producing glycosphingolipids; targeted by some NPC treatments

Cerebrospinal Fluid (spinal fluid) - The fluid that surrounds the brain and spinal cord; can be sampled to assess the state of the disease and is being used as a delivery route for some NPC treatments under development

Cherry Red Spot - A characteristic finding in the eye examination where the macula appears as a red spot surrounded by a pale area; this finding is present in some ASMD patients and as well as patients with other lysosomal storage diseases

Cholesterol metabolism - The body’s process of producing, using, and breaking down cholesterol

Clinical Trial - A research study that tests new treatments in people to determine safety and effectiveness

Coagulation Studies - Blood tests that measure how well blood clots; important to monitor in patients with liver disease or those taking certain medications

Cognitive Impairment - Problems with thinking, memory, and mental processing

Cohort - A group of people followed over time in a research study to observe outcomes and disease progression; can be prospective (following forward in time) or retrospective (looking back at past data)

Combination Therapy - Using two or more medications together

Compassionate Use – A treatment option that allows the use of an unauthorized medicine. Under strict conditions, products in development can be made available to groups of patients who have a disease with no satisfactory authorized therapies and who cannot enter clinical trials

Creatinine - A kidney-related blood test marker that may increase with some NPC medications

Cyclo Therapeutics – A biopharmaceutical company developing Trappsol Cyclo, a type of cyclodextrin. Cylco Therapeutics is a subsidiary of Rafael Holdings.

Cyclodextrin - A type of molecule under study that can help remove trapped cholesterol and other fatty substances from cells

Demyelination - The loss or damage of myelin, the protective covering around nerve fibers; can occur in NPC and contributes to neurological symptoms

Dexel Pharma - Manufacturer of Yargesa (miglustat)

Digital Health Technology – the use of information and communications in medicine and other health professions to manage illnesses and health risks and to promote wellness.

Disease Progression - How a condition like NPC worsens or advances over time

Dosing Schedule - The specific timing and frequency for taking medications

Double-Blind - A clinical trial design where neither the participants nor the researchers know who is receiving the active treatment versus placebo, helping to eliminate bias in results

Drug Interactions - When one medication affects how another medication works in the body

Drug Repurposing – The process of discovering and developing new therapeutic uses for existing drugs that have already been approved for a different condition. An example is the investigation of efavirenz for use in NPC

Dual Inhibitor - A drug that blocks two different enzymes or pathways simultaneously

Dysphagia - Difficulty swallowing; a common symptom in NPC that can affect eating, drinking, and taking medications

Demyelination - The loss or damage of myelin, the protective covering around nerve fibers; can occur in NPC and contributes to neurological symptoms

Dexel Pharma - Manufacturer of Yargesa (miglustat)

Digital Health Technology – The use of information and communications in medicine and other health professions to manage illnesses and health risks and to promote wellness.

Disease Progression - How a condition like NPC worsens or advances over time

Dosing Schedule - The specific timing and frequency for taking medications

Double-Blind - A clinical trial design where neither the participants nor the researchers know who is receiving the active treatment versus placebo, helping to eliminate bias in results

Drug Interactions - When one medication affects how another medication works in the body

Drug Repurposing – The process of discovering and developing new therapeutic uses for existing drugs that have already been approved for a different condition. An example is the investigation of efavirenz for use in NPC

Dual Inhibitor - A drug that blocks two different enzymes or pathways simultaneously

Dysphagia - Difficulty swallowing; a common symptom in NPC that can affect eating, drinking, and taking medications

Efavirenz - A medication approved by the FDA to treat HIV that is being studied as a potential treatment for NPC

End Point (clinical trial endpoint) – The main goal or the specific thing the researchers are looking for to decide if the treatment was successful. It’s a measurable outcome that tells them if something changed because of the treatment.

Energy Metabolism - How cells produce and use energy

Enzyme replacement therapy (ERT) – A treatment approach used for certain genetic disorders where the body lacks or produces insufficient amounts of specific enzymes needed for normal cellular function. Xenpozyme (olipudase alfa) is an enzyme replacement therapy for ASMD.

European Medicines Agency (EMA) - The regulatory body that approves medications in Europe

Expanded Access Program (EAP) – The formal plan under which access to an investigational drug can be provided to a group of patients prior to being approved by the FDA outside of a clinical trial.

Extension Study – A subsequent, usually longer, clinical trial that allows participants from a “parent” clinical trial to continue receiving the same treatment to gather more long-term safety, tolerability, and effectiveness data

FDA (Food and Drug Administration) - The U.S. regulatory body that approves medications

Feeding Tube (G-tube) - A medical device that allows medication delivery directly to the stomach

Fetal Harm - Potential damage to an unborn baby from certain medications

Gaucher Disease - Another lysosomal storage disorder that has features similar to ASMD; miglustat is approved for this condition in the U.S.

Gene Therapy - An experimental treatment approach that involves introducing genetic material into cells to correct defective genes or provide new cellular functions

Glycosphingolipids - Fatty substances that accumulate abnormally in some lysosomal diseases

Granules - The powder form of AQNEURSA that must be mixed with liquid

Heat Shock Proteins (HSPs) - Natural protective proteins that help cells survive stress and repair damage

Hepatic Function Panel - A group of blood tests that assess liver function, including tests for liver enzymes, bilirubin, and protein levels; important for monitoring patients with ASMD and NPC

Hepatosplenomegaly - Enlargement of both the liver and spleen; can occur in both ASMD and NPC

Hives (Urticaria) - A skin reaction that can occur as an allergic response to medications

HP-β-CD (2-hydroxypropyl-β-cyclodextrin) - A specific type of cyclodextrin under study for the potential treatment of NPC

Hypersensitivity Reactions - Allergic reactions that can range from mild to severe

Industry – The pharmaceutical and biotechnology companies that research, develop, manufacture, and market new medicines

Insurance Appeal – Formal process to challenge a health insurance company’s decision to deny a claim, service, or benefit you believe should be covered. It involves two main steps: an internal appeal, where the insurer reviews its own denial, and an external appeal, where an independent third party makes the final decision if the internal appeal is unsuccessful. You have the right to appeal when your plan denies payment for treatment, coverage, or a service.

IntraBio - A biopharmaceutical company that is the manufacturer of Aqneursa (levacetylleucine)

Intrathecal - Method of drug delivery directly into the cerebrospinal fluid around the brain and spinal cord

Intravenous (IV) - Method of drug delivery directly into the bloodstream through a vein

Johnson & Johnson - Manufacturer of Zavesca (miglustat)

Large Molecule – A complex biological agent (like a protein and antibody) produced in living systems and generally requiring injection to be administered.

Levacetylleucine - Generic name for Aqneursa; also called by its chemical name N-acetyl-L-leucine

Liver Tests - Blood tests that check liver function; may change with some NPC medications

Lumbar Puncture - A procedure (spinal tap) used to deliver medication directly into the cerebrospinal fluid

Lysosome - Cellular compartments that normally break down and recycle cellular waste; dysfunction of lysosomes is central to ASMD and NPC pathology

Lysosomal Storage Disorder (LSD) – A group of genetic diseases, including ASMD and NPC, where substances accumulate in cellular compartments called lysosomes

Managed Access Program – Allows patients to receive a medicine that is not yet fully approved or available in their country, typically for serious conditions when no other treatment options exist. These programs ensure that access is controlled and monitored, often under specific compassionate use or expanded access regulations

Mandos Health – A biopharmaceutical company developing adrabetadex, a type of cyclodextrin. Mandos is a subsidiary of Beren Therapeutics

Mandose - A sugar molecule that can be used as a biomarker or therapeutic target in some lysosomal storage disorders; involved in cellular recognition and trafficking processes

Medicaid – A joint federal and state public health insurance program that provides low-cost health coverage to low-income individuals, families, pregnant women, elderly adults, and people with disabilities. Administered at the state level but funded jointly by federal and state governments, Medicaid offers a wide range of medical services, including hospital care, doctor visits, and long-term care, with eligibility and covered benefits varying by state.

Medicaid Waiver – A formal agreement between a state and the federal government that allows the state to test new ways to deliver Medicaid services or provide coverage for people who might not normally be eligible. The most common waivers, Section 1915(c) Home and Community-Based Services (HCBS) waivers, enable states to offer long-term care services in a person’s home or community, rather than in an institution, by providing services like personal care, respite care, and home modifications.

Medicare – A federal health insurance program in the U.S. primarily for people aged 65 or older, but also for certain younger people with disabilities or End-Stage Renal Disease (ESRD). It helps pay for healthcare costs, broken down into different parts (A, B, C, and D) that cover hospital stays, doctor services, outpatient care, and prescription drugs.

Miplyffa - Brand name for arimoclomol; approved by the FDA for use in combination with miglustat for the treatment of neurological symptoms of NPC

Miglustat - A drug with a complex mechanism of action in treating Gaucher disease (FDA approved) and NPC (off-label use) that includes reducing the production of glycosphingolipids through a process known as substrate reduction therapy; brand names include Zavesca and Yargesa

Monotherapy - Treatment with a single medication rather than combination therapy

Movement Disorders - Problems with coordination, balance, and motor control that can occur in ASMD and NPC

N-acetyl-L-leucine - Chemical name for levacetylleucine (Aqneursa)

NDA (New Drug Application) - The formal application submitted to the FDA requesting approval to market a new drug in the United States

Neurological Decline - The progressive worsening of brain-related symptoms

Neurological Progression - The worsening of brain-related symptoms over time

Newborn Screening - Testing performed on newborn babies to identify genetic disorders and other conditions early in life; some forms of Niemann-Pick disease can be detected through newborn screening programs

Niemann-Pick Disease Type C (NPC) - A rare genetic disorder where cholesterol and other fatty substances accumulate in cells, causing progressive neurological damage

NPC-CSS (Niemann-Pick Type C Clinical Severity Scale) – a standardized tool used by clinicians to quantify the severity and progression of Niemann-Pick type C disease. It assesses various symptoms, providing a numerical score that helps track disease course and evaluate the impact of therapies over time.

Nizubaglustat - An investigational drug that acts as a dual inhibitor to reduce cholesterol in cells via substrate reduction, meaning it blocks two different enzymes involved in the body’s processing of certain lipids, or fats currently under development for the treatment of NPC

Non-lysosomal Glucosylceramidase - An enzyme involved in breaking down certain fatty substances; targeted by some treatments

Observational Study - A type of research study where investigators observe participants without intervening or assigning treatments; includes cohort studies, case-control studies, and cross-sectional studies

Off-Label - The practice of prescribing an FDA-approved medication for a condition, age group, or dosage different from what it was originally approved for; this type of prescribing is legal and common in medical practice

Olipudase alfa – Generic name for Xenpozyme

Oligosaccharide – A type of molecule made of multiple sugars linked together. These molecules can serve many functions that impact cell function and cell communication.

Open-label Study - A clinical trial where both patients and doctors know what treatment is being given

Oral Administration - Taking medication by mouth

Organomegaly - Enlargement of organs, particularly the liver, spleen, or other internal organs; commonly seen in lysosomal storage disorders like ASMD and NPC

Patient Reported Outcome (PRO) - Measurements of health status, symptoms, or quality of life reported directly by patients rather than healthcare providers

Peripheral Neuropathy - Nerve damage that can cause numbness, tingling, or weakness, especially in hands and feet

Petechiae - Small, pinpoint red or purple spots on the skin caused by minor bleeding from broken capillary blood vessels; can indicate low platelet count or bleeding disorders

Pharmacodynamics - The study of what a drug does to the body

Pharmacokinetics - The study of what the body does to a drug (how it is absorbed, distributed, metabolized, and eliminated)

Pharmacy Benefits Manager (PBM) – A third-party administrator that manages prescription drug benefits on behalf of health insurance companies, large employers, and other payers. PBMs negotiate drug prices with pharmaceutical manufacturers, create formularies (lists of covered drugs), manage pharmacy networks, and process prescription claims. They act as intermediaries between health insurance plans, pharmacies, and drug manufacturers.

Phase I Trial – A small trial involving healthy volunteers that is designed to determine the safety and tolerability of a drug.

Phase II Trial – A study involving people with a specific disease to determine efficacy while still monitoring for safety as is done in a phase I study.

Phase III Trial – Often referred to as a confirmatory trial, this study determines efficacy of an intervention or drug compared to the standard of care at that time. These trials are typically larger than phase I or II trials.

Phase IV Trial – A study done after a drug is approved and available designed to assess a therapy’s long-term risks, benefits and optimal use.

Placebo - An inactive treatment used as a control in clinical trials to compare against the actual medication being tested

Plain Language Summary – A simplified version of detailed scientific or medical article.

Prescribing Information - Also known as “the label,” the official documentation that provides detailed information about how to use a medication safely

Prior Authorization – A process requiring a prescriber to get approval from an insurance company before they reimburse for a specific medication or treatment

Protein Folding - The process by which proteins achieve their proper shape and function; enhanced by heat shock proteins

Randomized - A study design where participants are assigned to treatment groups by chance rather than by choice, helping to eliminate bias in clinical trials

Randomized Controlled Trial (RCT) - The gold standard study design where patients are randomly assigned to either the treatment or control groups

Registry - A systematic collection of data about patients with a particular condition, used to track disease progression and treatment outcomes over time

Regulators – Government agencies or bodies responsible for overseeing and approving new medicines before they can be sold to the public. Their main job is to make sure that any new drug is both safe for patients to use and effective for the condition it’s meant to treat.

Retail Pharmacy – A licensed establishment that dispenses prescription and over-the-counter medications directly to the public at retail prices, typically in a community setting.

Retrospective Study - A research study that looks backward in time, examining data that has already been collected to identify patterns or outcomes.

Sachets - Single-use packets containing Aqneursa granules.

Sanofi – A biopharmaceutical company that is the manufacturer of Xenpozyme (olipudase alfa).

Seizures - A sudden, abnormal burst of electrical activity in the brain that can cause temporary changes in behavior, movement, consciousness, or sensation.

Sensitivity - In medical testing, the ability of a test to correctly identify people who have a disease (true positive rate); important for diagnostic tests and screening programs.

Side Effects - Unwanted effects that can occur when taking medications.

Single-Blind - A clinical trial design where either the participants or the researchers (but not both) know who is receiving the active treatment versus placebo

Small Molecule – A low-molecular-weight (small) compound with a simple structure that is often made chemically (as opposed to being made in a living system), allowing it to easily enter cells and cross the blood-brain barrier. These are often administered orally.

Spasticity - Muscle stiffness and involuntary contractions that can occur due to damage to the brain and spinal cord pathways that control movement

Specificity - In medical testing, the ability of a test to correctly identify people who do not have a disease (true negative rate); important for avoiding false positive results

Step Therapy (aka step protocol) – A health plan program that requires patients to try a more cost-effective, often generic, medication for a condition before covering a more expensive, less cost-effective one.

Substrate Reduction Therapy - Treatment approach that reduces production of harmful substances rather than trying to break them down; the mechanism of action for miglustat and nizubaglustat

Summary of Product Characteristics (SmPC) - European equivalent of prescribing information

Supranuclear Gaze Palsy - A characteristic eye movement disorder in NPC where patients have difficulty moving their eyes up and down voluntarily

Thrombocytopenia - A condition characterized by abnormally low platelet count in the blood, which can lead to increased bleeding and bruising; may occur in some lysosomal storage disorders like ASMD and NPC

Transcription - The cellular process of copying genetic information from DNA to RNA

Transaminase - Liver enzymes (including ALT and AST) that are measured in blood tests to assess liver function; levels may be elevated in patients with liver involvement from ASMD and NPC or as a side effect of medications

Tremor - Shaking or trembling that can occur in NPC or as a medication side effect

Trappsol Cyclo - Proprietary name for a specific HP-β-CD (2-hydroxypropyl-β-cyclodextrin) currently under study and development for NPC

Upper Respiratory Infections - Common cold-like symptoms that can occur as medication side effects

White Matter Disease - Damage to the white matter of the brain, which contains nerve fibers that connect different brain regions. These findings are commonly seen on MRIs

Xenpozyme – Brand name for olipudase alfa, an enzyme replacement therapy approved by the FDA used to treat the non-neurologic symptoms in ASMD

Yargesa - Brand name for miglustat manufactured by Dexel Pharma approved by the FDA for the treatment of Gaucher disease

Zavesca - Brand name for miglustat manufactured by Johnson & Johnson approved by the FDA for the treatment of Gaucher disease

Zevra Therapeutics – A biopharmaceutical company that is the manufacturer of Miplyffa (arimoclomol)

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