NCT03701568

Brief Summary

This is a medical chart review study to collect information for patients who have been taking pyrimidine nucleosides for treatment of TK2 deficiency. Information from the time of onset of symptoms will be collected to describe the pre treatment course of TK2 deficiency.

Trial Health

90
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
38

participants targeted

Target at P25-P50 for all trials

Timeline
Completed

Started Nov 2018

Shorter than P25 for all trials

Geographic Reach
3 countries

8 active sites

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

September 27, 2018

Completed
13 days until next milestone

First Posted

Study publicly available on registry

October 10, 2018

Completed
1 month until next milestone

Study Start

First participant enrolled

November 19, 2018

Completed
5 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 30, 2019

Completed
1 month until next milestone

Study Completion

Last participant's last visit for all outcomes

May 31, 2019

Completed
Last Updated

September 1, 2023

Status Verified

August 1, 2023

Enrollment Period

5 months

First QC Date

September 27, 2018

Last Update Submit

August 29, 2023

Conditions

Thymidine Kinase 2 (TK2)

Keywords

myopathy, muscle weakness, hypotonia, dysphagia, ptosis

Outcome Measures

Primary Outcomes (1)

  • Diagnosis

    genetic testing (previously conducted)

    3 months

Secondary Outcomes (8)

  • Clinical course

    3 months

  • Clinical course

    3 months

  • Motor function and ambulatory assessments

    3 months

  • Motor function and ambulatory assessments

    3 months

  • Motor function and ambulatory assessments

    3 months

  • +3 more secondary outcomes

Interventions

dC/dTDRUG

Collection of retrospective data from TK2 patients previously treated with dC/dT

Also known as: deoxycytidine/deoxythymidine

Eligibility Criteria

Sexall
Healthy VolunteersNo
Age GroupsChild (0-17), Adult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

Patients with TK2 deficiency who have received treatment with pyrimidine nucleosides

You may qualify if:

  • Signed informed consent by the patient or parent(s)/legally authorized representative (LAR) and/or assent by the patient (when applicable), unless the associated institutional review board (IRB) or ethics committee (EC) provides an appropriate consent waiver
  • Confirmed genetic mutation in the TK2 gene
  • Availability of medical records for each patient from the time of onset of symptoms
  • Patient has taken pyrimidine nucleos(t)ides (dCMP/dTMP and/or dC/dT) as substrate enhancement therapy for TK2 deficiency
  • Most recent patient visit at which efficacy and/or safety parameters were collected occurred between 01 June 2018 and 15 December 2018

You may not qualify if:

  • \. Presence of other genetic disease or polygenic disease

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (8)

Columbia University Medical Center

New York, New York, 10032, United States

Location

Rambam Hospital

Haifa, 3109601, Israel

Location

Wolfson Medical Center

Holon, 5822012, Israel

Location

Western Galilee Hospital

Nahariya, 89 כביש, Israel

Location

Hospital Vall d'Hebron

Barcelona, 08035, Spain

Location

Sant Joan de Déu Hospital

Barcelona, 08950, Spain

Location

Hospital 12 de Octubre

Madrid, 28041, Spain

Location

Hospital Universitario Virgen del Rocio

Seville, 41013, Spain

Location

Related Publications (1)

  • Dominguez-Gonzalez C, Chiang C, Colson AO, Rebollo Mesa I, Baixauli E, Quan J, VanMeter S, Hirano M. Pyrimidine Nucleos(t)ide Therapy in Patients With Thymidine Kinase 2 Deficiency: A Multicenter Retrospective Chart Review Study. Neurology. 2025 Sep 23;105(6):e213908. doi: 10.1212/WNL.0000000000213908. Epub 2025 Sep 5.

    PMID: 40911819DERIVED

Biospecimen

Retention: SAMPLES WITH DNA

When available, test reports maybe obtained (eg, reports from genetic testing, muscle biopsy) as well as available research biological samples (eg, blood or tissue samples that may be tested for biomarkers of disease and/or effects of medications to treat the mitochondrial disease).

MeSH Terms

Conditions

Muscular DiseasesMuscle WeaknessMuscle HypotoniaDeglutition DisordersBlepharoptosis

Interventions

DeoxycytidineThymidine

Condition Hierarchy (Ancestors)

Musculoskeletal DiseasesNeuromuscular DiseasesNervous System DiseasesNeuromuscular ManifestationsNeurologic ManifestationsPathologic ProcessesPathological Conditions, Signs and SymptomsSigns and SymptomsEsophageal DiseasesGastrointestinal DiseasesDigestive System DiseasesPharyngeal DiseasesOtorhinolaryngologic DiseasesEyelid DiseasesEye Diseases

Intervention Hierarchy (Ancestors)

CytidinePyrimidine NucleosidesPyrimidinesHeterocyclic Compounds, 1-RingHeterocyclic CompoundsDeoxyribonucleosidesNucleosidesNucleic Acids, Nucleotides, and Nucleosides

Study Officials

  • UCB Cares

    001 844 599 2273

    STUDY DIRECTOR

Study Design

Study Type
observational
Observational Model
CASE ONLY
Time Perspective
RETROSPECTIVE
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

September 27, 2018

First Posted

October 10, 2018

Study Start

November 19, 2018

Primary Completion

April 30, 2019

Study Completion

May 31, 2019

Last Updated

September 1, 2023

Record last verified: 2023-08

Data Sharing

IPD Sharing
Will not share

Locations

IL(3)ES(4)US(1)