Updated June 2026 · ClinicalTrials.gov
Deoxynucleosides Pyrimidines as Treatment for Mitochondrial Depletion Syndrome
A Phase II, Monocenter, Single Arm Study To Assess The Safety and Efficacy Of Combination Deoxycytidine and Deoxythymidine For Mitochondrial Depletion Disorders
Deoxynucleosides Pyrimidines as Treatment for Mitochondrial Depletion Syndrome (NCT04802707) is a Phase 2 interventional studying Mitochondrial Diseases and Mitochondrial Encephalomyopathy, sponsored by Kenneth Myers, MD. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.
About This Trial
Mitochondrial DNA (mtDNA) depletion syndromes (MDS) are a genetically and clinically heterogeneous group of autosomal recessive disorders that are characterized by a severe reduction in mtDNA content leading to impaired energy production in affected tissues and organs. MDS are due to defects in mtDNA maintenance caused by mutations in nuclear genes that function in either mitochondrial nucleotide synthesis. MDS are phenotypically heterogeneous and usually classified as myopathic, encephalomyopathic, hepatocerebral or neurogastrointestinal. No efficacious therapy is available for any of these disorders. Affected individuals should have a comprehensive evaluation to assess the degree of involvement of different systems. Treatment is directed mainly toward providing symptomatic management. No treatment for MDS. Clinical trials studies and in vitro/in vivo research studies showed that the enhancement of the salvage pathway by increasing the availability of deoxyribonucleosides needed for each specific genetic defect prevents mtDNA depletion. Early recognition and immediate therapy to restore mitochondrial function could potentially improve clinical course. Confirming the benefit of deoxynucleosides as a safe and potentially efficacious therapy, will lead to the availability of the first specific and effective treatment for Mitochondria Depletion Disorders. In this phase II Trial a mix of Deoxynucleosides Pyrimidine (Deoxycytidine dC and Deoxythymidine dT) will be used as early treatment of MDS. The dose used has been already used in other clinical trials, and appears to effective and well-tolerated. The subjects included are children (0-18Y), with positive MDS diagnosis and express mutations in one of the following genes: POLG, POLG2, C10orf2, RRM2B, MPV17, SUCLA2, SUCLG1, FBXL4, DTYMK. Subjects with MDS expressing neurological phenotypes dysfunction.
What Stage of Research Is This?
Phase 2 trials evaluate whether a treatment actually works against Mitochondrial Diseases and continue monitoring side effects. Phase 2 enrolls larger groups (typically 100–300 patients) and produces the first real efficacy signal. A successful Phase 2 readout is what unlocks the much larger Phase 3 confirmatory trials needed for FDA approval.
This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.
Target enrollment of 200 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Mitochondrial Diseases subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.
Who May Be Eligible (Plain English)
These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.
Original Eligibility Criteria
View original clinical language
Treatments Being Tested
deoxycytidine and deoxythymidine
The Investigational Product (IP) dC/dT100-400 will be administered orally every day (QD) and the dose is divided over trid or bid for the daily dose of 100 mg/kg from Day 1-7, 200 mg/kg from Day 8-14, 300 mg/kg from Day 15- 21 and 400 mg/kg from Day 22 to 1825. Doses was chosen according to the safety and efficacy doses used in the literature.
Locations (1)
Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.
How to Talk to Your Doctor About This Trial
Bring the printable summary of this trial — including the NCT ID (NCT04802707), the sponsor (Kenneth Myers, MD), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.
Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.
Authoritative Sources
The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.
Frequently Asked Questions
What is the NCT04802707 clinical trial studying?
Mitochondrial DNA (mtDNA) depletion syndromes (MDS) are a genetically and clinically heterogeneous group of autosomal recessive disorders that are characterized by a severe reduction in mtDNA content leading to impaired energy production in affected tissues and organs. MDS are due to defects in mtDNA maintenance caused by mutations in nuclear genes that function in either mitochondrial nucleotide synthesis. MDS are phenotypically heterogeneous and usually classified as myopathic, encephalomyopathic, hepatocerebral or neurogastrointestinal. No efficacious therapy is available for any of these … The full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.
Who can participate in NCT04802707?
Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.
How do I contact the trial site for NCT04802707?
Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.
Is participating in a clinical trial safe?
Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.
Where can I verify the data on this page?
Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.
How This Page Is Built
Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.
Source: ClinicalTrials.gov API v2 record for NCT04802707. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT04802707. Data: ClinicalTrials.gov."
Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.
Last updated 2026-06-26 · Data from ClinicalTrials.gov.