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NCT03639701 · ClinicalTrials.gov registry record · Phase 1

Treatment of TK2 Deficiency With Thymidine and Deoxycytidine

A Phase 1 study of Thymidine Kinase 2 Deficiency and Mitochondrial DNA Depletion Syndrome 2 Myopathic Type, sponsored by Columbia University.

Active
Registry status
Phase 1
Development phase
23
Enrollment target
1
Study location

NCT03639701: Active Phase 1 study of Thymidine Kinase 2 Deficiency and Mitochondrial DNA Depletion Syndrome 2 Myopathic Type, sponsored by Columbia University.

NCT03639701 is a Phase 1 study of Thymidine Kinase 2 Deficiency and Mitochondrial DNA Depletion Syndrome 2 Myopathic Type that is active but no longer recruiting, run by Columbia University. The registered enrollment target is 23 participants, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (62% lower). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT03639701, a Phase 1 study of Thymidine Kinase 2 Deficiency and Mitochondrial DNA Depletion Syndrome 2 Myopathic Type, is active but no longer recruiting, sponsored by Columbia University.

ACTIVE NOT RECRUITING
Registry status
Phase 1
Development phase
23 participants
Enrollment target
1
Study location

Study Summary

Patients with confirmed mitochondrial DNA depletion syndrome 2 (thymidine kinase 2 \[TK2\] deficiency) have reduced levels of nucleotides (deoxythymidine monophosphate and deoxycytidine monophosphate) for mitochondrial DNA synthesis. This results in mitochondrial DNA depletion syndrome (i.e less number of functional mitochondrial DNA). Patients with confirmed TK2 deficiency will be treated with open label deoxythymidine (dThd) and deoxycytidine (dCyt), which are nucleotide precursors, with the expectation that the cells could make additional mitochondrial DNA. This in turn may help reduce the clinical symptoms.

Primary Outcome

Number of participants with treatment-related elevated alanine aminotransferase (ALT) serum level relative to upper limit of normal (expressed as ratios) grade 3 or higher as defined by CTCAE 4.03.

Interventions

  • DRUG Thymidine

Study Locations (1)

New York

  • Columbia University Irving Medical Center - New York

Trial Details

FieldValue
Enrollment Target 23 participants
Start Date 2017-05-16
Est. Completion 2026-12-31
Phase Phase 1
Columbia University

958 total trials

What the registry record for NCT03639701 still lists

NCT03639701 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 23 participants, a relatively small participant target, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (62% lower).

The record links to 2 conditions, with Thymidine Kinase 2 Deficiency appearing as the primary indexed condition, and to 1 intervention - of which Thymidine is the first listed.

NCT03639701 reports a single indexed study location in New York.

Frequently Asked Questions

What is clinical trial NCT03639701 about?

NCT03639701 is a clinical study titled "Treatment of TK2 Deficiency With Thymidine and Deoxycytidine". Patients with confirmed mitochondrial DNA depletion syndrome 2 (thymidine kinase 2 \[TK2\] deficiency) have reduced levels of nucleotides (deoxythymidine monophosphate and deoxycytidine monophosphate) for mitochondrial DNA synthesis. This results in mitochondrial DNA depletion syndrome (i.e less num...

What is the current status of trial NCT03639701?

This trial is currently active not recruiting. It is a Phase 1 study. The enrollment target is 23 participants. The study started on 2017-05-16. Estimated completion is 2026-12-31.

What conditions does trial NCT03639701 study?

This clinical trial studies the following conditions: Thymidine Kinase 2 Deficiency, Mitochondrial DNA Depletion Syndrome 2 Myopathic Type.

What interventions are being tested in trial NCT03639701?

The interventions under investigation include: Thymidine (DRUG).

Who is sponsoring clinical trial NCT03639701?

This trial is sponsored by Columbia University, which has 958 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT03639701 being conducted?

This trial has 1 study location across New York. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Thymidine Kinase 2 Deficiency

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT03639701's enrollment target sits among peer trials

23 1596th of 2000 higher than 400 of 2,000 other Phase 1 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 1 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT03639701, the US trial registry maintained by the National Library of Medicine. NCT03639701 (small enrollment · single site footprint · active not recruiting) retrieved and formatted by PlainTrial, see methodology.