Neurological RegressionNCT00029965
Natural History of Glycosphingolipid Storage Disorders and Glycoprotein Disorders
An observational study of Neurological Regression and Myoclonus, run by National Human Genome Research Institute (NHGRI) at 1 site in United States.
Trial summary
Study description: This is a natural history study that will evaluate any patient with enzyme or DNA confirmed GM1 or GM2 gangliosidosis, sialidosis or galactosialidosis. Patients may be evaluated every 6 months for infantile onset disease, yearly for juvenile onset and approximately every two years for adult-onset… Read more about this study
- Who is it for?
- Ages 1 day to 100 years
- Conditions the study is for
- Neurological Regression, Myoclonus, Cherry Red Spot
- How many people
- 200 participants
- Where
- 1 siteUnited States
- Study dates
- 6 Feb 2002to not given
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 1 day to 100 years
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: Patients with Lysosomal Storage Diseases and Glycoprotein Disorders.
Who may be able to join
- Any individual with GM1 or GM2 gangliosidosis, sialidosis or galactosialidosis documented by enzyme deficiency or mutation analysis in a CLIA-approved laboratory will be eligible for the study.
Who cannot join
- There will be no exclusion based on race, gender, or ethnicity; however particular ethnic groups may be overrepresented due to the frequency of the diseases in a specific population (e.g., Ashkenazi Jews in infantile and adult GM2 and Roma "travelers" in juvenile GM1). The majority of juvenile subjects will have severely impaired decision-making and even informed assent in older children may not be possible. Children with Morquio B and sialidosis type 1 disease are not expected to be cognitively impaired. The children with Morquio B and sialidosis type 1 ages 7-11 years will be asked to give verbal assent and ages 12-17 years will be asked to give written assent to the protocol. Some subjects who have reached the age of 18 may need to have legally authorized representative (usually their parents) sign consent on their behalf.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
National Institutes of Health Clinical Center
Bethesda, Maryland, 20892
For more information at the NIH Clinical Center contact Office of Patient Recruitment (OPR), 800-411-1222 ext. TTY dial 711, ccopr@nih.gov
About this study
Study description:
This is a natural history study that will evaluate any patient with enzyme or DNA confirmed GM1 or GM2 gangliosidosis, sialidosis or galactosialidosis. Patients may be evaluated every 6 months for infantile onset disease, yearly for juvenile onset and approximately every two years for adult-onset disease as long as they are clinically stable to travel. Data will be evaluated serially for each patient, and cross-sectionally for patients of similar ages and genotypes. Genotype-phenotype correlations will be made where possible although these are rare disorders and the majority of the patients are compound heterozygotes.
Read more
Objectives:
To study the natural history and progression of neurodegeneration in individuals with glycosphingolipid storage disorders (GSL), GM1 and GM2 gangliosidosis, and glycoprotein (GP) disorders including sialidosis and galactosialidosis using clinical evaluation of patients and patient/parent surveys.
To develop sensitive tools for monitoring disease progression.
To identify biological markers in blood, cerebrospinal fluid, and urine that correlate with disease severity and progression and can be used as outcome measures for future clinical trials.
To further understand and characterize the mechanisms of neurodegeneration in GSL and GP storage disorders across the spectrum of disease beginning with ganglioside storage in fetal life.
Endpoints:
Exploring the natural history of Lysosomal Storage Diseases and Glycoprotein Disorders
Study Population:
Patients with enzyme or DNA confirmed GM1 or GM2 gangliosidosis, sialidosis or galactosialidosis. Accrual ceiling is 200 participants. No exclusions based on age, gender, demographic group, or demographic location. Patients included in our study are those that are seen at the NIH Clinical Center, subjects that have only sent in blood samples, as well as those who complete the questionnaire or provided head circumference measures.
Read the detailed description
The GM1 and GM2 gangliosidoses are rare lysosomal storage disorders that primarily affect the brain and are uniformly fatal. The glycoproteinoses sialidosis and galactosialidosis are ultra-rare disorders involving predominantly the skeletal and central nervous systems that are likewise fatal or severely debilitating. No effective therapy for patients with these diseases has yet been demonstrated. Historically, since these disorders are fatal very little natural history information or disease characterization using modern medical techniques has been collected. This information is vital to establish the pattern of disease progression and to identify clinical, biochemical and biophysical markers that can be used as endpoints in future therapeutic trials.
This protocol aims to study the natural history of the GM1 and GM2 gangliosidoses, sialidosis and galactosialidosis in affected individuals of all ages, races and genders using medical technologies including MRI/MRS, DaTscan, Levodopa Challenge Testing (LCT), hearing evaluation and auditory evoked response testing, EEG, sleep study, EMG/NCV, echocardiogram and abdominal ultrasound as well as subspecialty evaluations in rehabilitative medicine (including gait analysis), ophthalmology, speech language pathology, neurology, and psychology. Biomarkers of disease progression may be explored in CSF, blood, stool, and urine samples for correlation with disease staging. Fibroblast cultures will be established for testing potential therapeutic agents. Some fibroblast lines will be used to create induced pluripotent stem cells (iPSC) for differentiation into neural tissues, more relevant for the study of these disorders that primarily affect the central nervous system (CNS). We hypothesize that relevant biomarkers will correlate with disease progression and will shed light on the pathophysiology of disease progression in these devastating disorders.
As a means of acquiring additional information, subjects or their parents may also be asked to complete a questionnaire regarding their medical and developmental history, initial clinical presentation of the disease and steps toward diagnosis. At their request, the same questionnaire may be sent to families who do not wish to undergo clinical evaluation at the NIH, who are medically fragile and unable to travel, or whose affected member(s) are already deceased.
We know that children with infantile GM2 gangliosidosis develop increasing macrocephaly as part of their disease. No "normal" curves for head circumference vs. age currently exist for this disorder. In an attempt to provide such curves to the clinical community parents may also be asked to provide head circumference data on their children whether they are being seen at NIH or whether a clinical questionnaire is being completed for children too medically fragile to travel or already deceased.
We know that for infantile onset disease the storage of ganglioside in neurons begins during the second trimester of pregnancy. In rare situations where carrier couples learned from prenatal diagnosis that they were carrying a fetus with infantile disease and had decided to terminate the pregnancy, we accepted samples of fetal tissue prior to June 5, 2019, for analysis of biomarkers including gene expression analysis that may lend clues as to the underlying pathogenesis of disease. This may lead to increased understanding of the early events in disease pathogenesis and suggest possible therapies.
We anticipate that information obtained from the small population of patients with glycosphingolipid and glycoprotein disorders evaluated in this study will have a broader impact on patients with other neurodegenerative lysosomal storage disorders and perhaps more common disorders of neurodegeneration.
- Conditions
- Neurological Regression, Myoclonus, Cherry Red Spot, Brain Atrophy
- Keywords
- Sialidosis, Lysosomal Storage, GM1 Gangliosidosis, GM2 Gangliosidosis, Natural History, Glycoprotein Disorders, Lysosomal Storage Disorder, Tay-Sachs, Sandhoff, Gaucher
- Medical subject headings
- Myoclonus, Mucolipidoses, Gangliosidosis, GM1, Gangliosidoses, GM2, Lysosomal Storage Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Glycoprotein Disorders | Glycoprotein Disorders | |
| Lysosomal Storage Diseases | Lysosomal Storage Diseases |
What is being measured
The primary outcome is the main question the study is designed to answer.
Exploring the natural history of Glycoprotein Disorders
Exploring the natural history of Glycoprotein Disorders
Measured: Assessed one to every two years
Natural history of Lysosomal Storage Diseases
Exploring the natural history of Lysosomal Storage Diseases
Measured: Assessed one to every two years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Jan 2002 (estimated)
- Study start6 Feb 2002
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (7)Papers the sponsor has linked to this study.
- Other trials for Neurological RegressionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- National Human Genome Research Institute (NHGRI)
- Sponsor type
- US National Institutes of Health
- Responsible party
- Sponsor
- Investigators
- Cynthia J Tifft, M.D., Principal investigator, National Human Genome Research Institute (NHGRI)
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00029965
- Sponsor's protocol ID
- 020107
- Other IDs
- 02-HG-0107
- Status last verified
- 16 Oct 2026
- First submitted
- 27 Jan 2002
- Last updated
- 5 Nov 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: There is not currently a plan to make IPD available, however, after publishing trial data, a plan to share IPD may be made.
Publications
Wada R, Tifft CJ, Proia RL. Microglial activation precedes acute neurodegeneration in Sandhoff disease and is suppressed by bone marrow transplantation. Proc Natl Acad Sci U S A. 2000 Sep 26;97(20):10954-9. doi: 10.1073/pnas.97.20.10954.
PubMed 11005868Cantor RM, Roy C, Lim JS, Kaback MM. Sandhoff disease heterozygote detection: a component of population screening for Tay-Sachs disease carriers. II. Sandhoff disease gene frequencies in American Jewish and non-Jewish populations. Am J Hum Genet. 1987 Jul;41(1):16-26.
PubMed 2955697Myerowitz R, Hogikyan ND. Different mutations in Ashkenazi Jewish and non-Jewish French Canadians with Tay-Sachs disease. Science. 1986 Jun 27;232(4758):1646-8. doi: 10.1126/science.3754980.
PubMed 3754980D'Souza P, Farmer C, Johnston JM, Han ST, Adams D, Hartman AL, Zein W, Huryn LA, Solomon B, King K, Jordan CP, Myles J, Nicoli ER, Rothermel CE, Mojica Algarin Y, Huang R, Quimby R, Zainab M, Bowden S, Crowell A, Buckley A, Brewer C, Regier DS, Brooks BP, Acosta MT, Baker EH, Vezina G, Thurm A, Tifft CJ. GM1 gangliosidosis type II: Results of a 10-year prospective study. Genet Med. 2024 Jul;26(7):101144. doi: 10.1016/j.gim.2024.101144. Epub 2024 Apr 16.
PubMed 38641994Han ST, Hirt A, Nicoli ER, Kono M, Toro C, Proia RL, Tifft CJ. Gene expression changes in Tay-Sachs disease begin early in fetal brain development. J Inherit Metab Dis. 2023 Jul;46(4):687-694. doi: 10.1002/jimd.12596. Epub 2023 Feb 5.
PubMed 36700853Luckett A, Yousef M, Tifft C, Jenkins K, Smith A, Munoz A, Quimby R, Porter FD, Dang Do AN. Anesthesia outcomes in lysosomal disorders: CLN3 and GM1 gangliosidosis. Am J Med Genet A. 2023 Mar;191(3):711-717. doi: 10.1002/ajmg.a.63064. Epub 2022 Dec 2.
PubMed 36461157Daich Varela M, Zein WM, Toro C, Groden C, Johnston J, Huryn LA, d'Azzo A, Tifft CJ, FitzGibbon EJ. A sialidosis type I cohort and a quantitative approach to multimodal ophthalmic imaging of the macular cherry-red spot. Br J Ophthalmol. 2021 Jun;105(6):838-843. doi: 10.1136/bjophthalmol-2020-316826. Epub 2020 Aug 4.
PubMed 32753397
Study at a glance
From the registry record, last updated by the sponsor on 5 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Natural History of Glycosphingolipid Storage Disorders and Glycoprotein Disorders
- ClinicalTrials.gov ID
- NCT00029965
- Acronym / sponsor ID
- 020107
- Conditions
- Neurological Regression, Myoclonus, Cherry Red Spot, Brain Atrophy
- Keywords
- Sialidosis, Lysosomal Storage, GM1 Gangliosidosis, GM2 Gangliosidosis, Natural History, Glycoprotein Disorders, Lysosomal Storage Disorder, Tay-Sachs
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 200 participants (estimated)
- Lead sponsor
- National Human Genome Research Institute (NHGRI)US National Institutes of Health
- Study start
- 6 Feb 2002 (actual)
- First posted
- 28 Jan 2002 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Study description:
This is a natural history study that will evaluate any patient with enzyme or DNA confirmed GM1 or GM2 gangliosidosis, sialidosis or galactosialidosis. Patients may be evaluated every 6 months for infantile onset disease, yearly for juvenile onset and approximately every two years for adult-onset disease as long as they are clinically stable to travel. Data will be evaluated serially for each patient, and cross-sectionally for patients of similar ages and genotypes. Genotype-phenotype correlations will be made where possible although these are rare disorders and the majority of the patients are compound heterozygotes.
Objectives:
To study the natural history and progression of neurodegeneration in individuals with glycosphingolipid storage disorders (GSL), GM1 and GM2 gangliosidosis, and glycoprotein (GP) disorders including sialidosis and galactosialidosis using clinical evaluation of patients and patient/parent surveys.
To develop sensitive tools for monitoring disease progression.
To identify biological markers in blood, cerebrospinal fluid, and urine that correlate with disease severity and progression and can be used as outcome measures for future clinical trials.
To further understand and characterize the mechanisms of neurodegeneration in GSL and GP storage disorders across the spectrum of disease beginning with ganglioside storage in fetal life.
Endpoints:
Exploring the natural history of Lysosomal Storage Diseases and Glycoprotein Disorders
Study Population:
Patients with enzyme or DNA confirmed GM1 or GM2 gangliosidosis, sialidosis or galactosialidosis. Accrual ceiling is 200 participants. No exclusions based on age, gender, demographic group, or demographic location. Patients included in our study are those that are seen at the NIH Clinical Center, subjects that have only sent in blood samples, as well as those who complete the questionnaire or provided head circumference measures.
Detailed description
The GM1 and GM2 gangliosidoses are rare lysosomal storage disorders that primarily affect the brain and are uniformly fatal. The glycoproteinoses sialidosis and galactosialidosis are ultra-rare disorders involving predominantly the skeletal and central nervous systems that are likewise fatal or severely debilitating. No effective therapy for patients with these diseases has yet been demonstrated. Historically, since these disorders are fatal very little natural history information or disease characterization using modern medical techniques has been collected. This information is vital to establish the pattern of disease progression and to identify clinical, biochemical and biophysical markers that can be used as endpoints in future therapeutic trials.
This protocol aims to study the natural history of the GM1 and GM2 gangliosidoses, sialidosis and galactosialidosis in affected individuals of all ages, races and genders using medical technologies including MRI/MRS, DaTscan, Levodopa Challenge Testing (LCT), hearing evaluation and auditory evoked response testing, EEG, sleep study, EMG/NCV, echocardiogram and abdominal ultrasound as well as subspecialty evaluations in rehabilitative medicine (including gait analysis), ophthalmology, speech language pathology, neurology, and psychology. Biomarkers of disease progression may be explored in CSF, blood, stool, and urine samples for correlation with disease staging. Fibroblast cultures will be established for testing potential therapeutic agents. Some fibroblast lines will be used to create induced pluripotent stem cells (iPSC) for differentiation into neural tissues, more relevant for the study of these disorders that primarily affect the central nervous system (CNS). We hypothesize that relevant biomarkers will correlate with disease progression and will shed light on the pathophysiology of disease progression in these devastating disorders.
As a means of acquiring additional information, subjects or their parents may also be asked to complete a questionnaire regarding their medical and developmental history, initial clinical presentation of the disease and steps toward diagnosis. At their request, the same questionnaire may be sent to families who do not wish to undergo clinical evaluation at the NIH, who are medically fragile and unable to travel, or whose affected member(s) are already deceased.
We know that children with infantile GM2 gangliosidosis develop increasing macrocephaly as part of their disease. No "normal" curves for head circumference vs. age currently exist for this disorder. In an attempt to provide such curves to the clinical community parents may also be asked to provide head circumference data on their children whether they are being seen at NIH or whether a clinical questionnaire is being completed for children too medically fragile to travel or already deceased.
We know that for infantile onset disease the storage of ganglioside in neurons begins during the second trimester of pregnancy. In rare situations where carrier couples learned from prenatal diagnosis that they were carrying a fetus with infantile disease and had decided to terminate the pregnancy, we accepted samples of fetal tissue prior to June 5, 2019, for analysis of biomarkers including gene expression analysis that may lend clues as to the underlying pathogenesis of disease. This may lead to increased understanding of the early events in disease pathogenesis and suggest possible therapies.
We anticipate that information obtained from the small population of patients with glycosphingolipid and glycoprotein disorders evaluated in this study will have a broader impact on patients with other neurodegenerative lysosomal storage disorders and perhaps more common disorders of neurodegeneration.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Glycoprotein Disorders | – | –Glycoprotein Disorders |
| Lysosomal Storage Diseases | – | –Lysosomal Storage Diseases |
Who may qualify
- Ages
- 1 day to 100 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
- Study population
- Patients with Lysosomal Storage Diseases and Glycoprotein Disorders.
Key inclusion criteria (1 listed)
- Any individual with GM1 or GM2 gangliosidosis, sialidosis or galactosialidosis documented by enzyme deficiency or mutation analysis in a CLIA-approved laboratory will be eligible for the study.
Key exclusion criteria (1 listed)
- There will be no exclusion based on race, gender, or ethnicity; however particular ethnic groups may be overrepresented due to the frequency of the diseases in a specific population (e.g., Ashkenazi Jews in infantile and adult GM2 and Roma "travelers" in juvenile GM1). The majority of juvenile subjects will have severely impaired decision-making and even informed assent in older children may not be possible. Children with Morquio B and sialidosis type 1 disease are not expected to be cognitively impaired. The children with Morquio B and sialidosis type 1 ages 7-11 years will be asked to give verbal assent and ages 12-17 years will be asked to give written assent to the protocol. Some subjects who have reached the age of 18 may need to have legally authorized representative (usually their parents) sign consent on their behalf.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Exploring the natural history of Glycoprotein Disorders
Time frame: Assessed one to every two years
Exploring the natural history of Glycoprotein Disorders
Natural history of Lysosomal Storage Diseases
Time frame: Assessed one to every two years
Exploring the natural history of Lysosomal Storage Diseases
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Nov 2026.
- Background: PubMed 11005868Wada R, Tifft CJ, Proia RL. Microglial activation precedes acute neurodegeneration in Sandhoff disease and is suppressed by bone marrow transplantation. Proc Natl Acad Sci U S A. 2000 Sep 26;97(20):10954-9. doi: 10.1073/pnas.97.20.10954.
- Background: PubMed 2955697Cantor RM, Roy C, Lim JS, Kaback MM. Sandhoff disease heterozygote detection: a component of population screening for Tay-Sachs disease carriers. II. Sandhoff disease gene frequencies in American Jewish and non-Jewish populations. Am J Hum Genet. 1987 Jul;41(1):16-26.
- Background: PubMed 3754980Myerowitz R, Hogikyan ND. Different mutations in Ashkenazi Jewish and non-Jewish French Canadians with Tay-Sachs disease. Science. 1986 Jun 27;232(4758):1646-8. doi: 10.1126/science.3754980.
- Derived from this study: PubMed 38641994D'Souza P, Farmer C, Johnston JM, Han ST, Adams D, Hartman AL, Zein W, Huryn LA, Solomon B, King K, Jordan CP, Myles J, Nicoli ER, Rothermel CE, Mojica Algarin Y, Huang R, Quimby R, Zainab M, Bowden S, Crowell A, Buckley A, Brewer C, Regier DS, Brooks BP, Acosta MT, Baker EH, Vezina G, Thurm A, Tifft CJ. GM1 gangliosidosis type II: Results of a 10-year prospective study. Genet Med. 2024 Jul;26(7):101144. doi: 10.1016/j.gim.2024.101144. Epub 2024 Apr 16.
- Derived from this study: PubMed 36700853Han ST, Hirt A, Nicoli ER, Kono M, Toro C, Proia RL, Tifft CJ. Gene expression changes in Tay-Sachs disease begin early in fetal brain development. J Inherit Metab Dis. 2023 Jul;46(4):687-694. doi: 10.1002/jimd.12596. Epub 2023 Feb 5.
- Derived from this study: PubMed 36461157Luckett A, Yousef M, Tifft C, Jenkins K, Smith A, Munoz A, Quimby R, Porter FD, Dang Do AN. Anesthesia outcomes in lysosomal disorders: CLN3 and GM1 gangliosidosis. Am J Med Genet A. 2023 Mar;191(3):711-717. doi: 10.1002/ajmg.a.63064. Epub 2022 Dec 2.
- Derived from this study: PubMed 32753397Daich Varela M, Zein WM, Toro C, Groden C, Johnston J, Huryn LA, d'Azzo A, Tifft CJ, FitzGibbon EJ. A sialidosis type I cohort and a quantitative approach to multimodal ophthalmic imaging of the macular cherry-red spot. Br J Ophthalmol. 2021 Jun;105(6):838-843. doi: 10.1136/bjophthalmol-2020-316826. Epub 2020 Aug 4.
- NIH Clinical Center Detailed Web PageLink provided by the sponsor.
- Individual participant dataSharing planned: Undecided. There is not currently a plan to make IPD available, however, after publishing trial data, a plan to share IPD may be made.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Cynthia J Tifft, M.D. principal investigator
National Human Genome Research Institute (NHGRI)
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Neurological Regression and Myoclonus, run by National Human Genome Research Institute (NHGRI) at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 5 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Jean M Johnston ((240) 515-1448, johnstonjm@mail.nih.gov), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Exploring the natural history of Glycoprotein Disorders (time frame: Assessed one to every two years). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT00029965, which also lists 7 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Nov 2026.