Reverse Transcriptase Inhibitors in Aicardi Goutières Syndrome

Study Overview
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Brief Summary
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The overall objectives are to explore the safety and efficacy of Reverse Transcriptase Inhibitors Tenofovir (TDF)/ Emtricitabine (FTC) administered in AGS affected children 2 to 18 years of age.

Detailed Description
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The investigators propose that a trial to assess the proof of principle that antiretroviral therapy through a drug combination of Tenofovir (TDF) and Emtricitabine (FTC) can decrease endogenous retroelement accumulation, and alter interferon signaling in Aicardi Goutières Syndrome (AGS) patients is reasonable and warranted at this time, based on existing in vitro and animal data. Additionally, this trial will further the investigators understanding of this disorder, measuring for the first time retroelements in human participants, exploring the retroviral burden in cerebrospinal fluid (CSF), the Interferon (IFN) signaling response, as well as evaluating antigen targets of autoimmunity and cytokines. If successful, this approach will clearly demonstrate the need for a larger trial of antiretrovirals in AGS with more clinically relevant outcomes.

Official Title
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Reverse Transcriptase Inhibitors in Aicardi Goutières Syndrome

Conditions
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Aicardi Goutières Syndrome

Intervention / Treatment
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* Drug: Tenofovir (TDF) and Emtricitabine (FTC)
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Molecular, neuroimaging, and clinical findings consistent with a diagnosis of AGS, with the exception of Double-stranded RNA-specific adenosine deaminase (ADAR1) and IFIH1, which are not postulated to result in nucleic acid accumulation Evidence of interferon activation such as elevation of CSF neopterin/tetrahydrobiopterin measured on the first evaluation. Ages 2-18 years (the age of 2 years is used because the drugs are FDA approved in children greater than 2 years) Weight of at least 10 kg Willingness to undergo serial lumbar punctures and blow draws for evaluation of laboratory based outcome measures Willingness to abstain from initiating the use of immune modulating therapies including corticosteroids Able to receive medications orally, by nasogastric (NG) tube or by Gastric (G)-tube No concomitant illness which would preclude safe participation as judged by the investigator Signed informed consent by the subject's legally acceptable representative Negative testing for HIV Negative testing for Hepatitis B Concurrent enrollment in the Myelin Disorders Biorepository Project (MDBP, ClinicalTrials.gov NCT03047369) and willingness to undergo associated procedures Exclusion Criteria: Age < 2 years or >18 years Hepatic insufficiency with liver function tests greater than 3-times the upper limit of normal Renal insufficiency with creatinine clearance <60 Significant malabsorption Any clinical or laboratory abnormality or medical condition that, at the discretion of the investigator, may put the subject at an additional risk by participating in this study HIV infection Hepatitis B infection Mutations in ADAR1 or IFIH1

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: TDF/FTC then Placebo<br>This is a double-blind, placebo-controlled, 2 arm, cross-over trial involving 34 children with clinical findings and molecular confirmation of Aicardi Goutieres Syndrome, who also have an abnormal interferon signature. For arm 1, half of the patients will receive TDF/FTC (a combination of Tenofovir [TDF] and Emtricitabine [FTC]) for the first 6 months of the study. There will be a one month washout period before starting on placebo for 6 months. | Drug: Tenofovir (TDF) and Emtricitabine (FTC)<br>* Tenofovir (TDF): a nucleotide reverse transcriptase inhibitor (NtRTI) an acyclic nucleotide analog of adenosine 5'-monophosphate. This is used in children as young as age 2. Emtricitabine (FTC): a nucleoside reverse transcriptase inhibitor (NRTI), a synthetic analog of cytidine which binds at the active site of the reverse transcriptase.<br>* Other names: Emtriva (Brand for emtricitabine);Other: Placebo<br>* Placebo for Tenofovir and Placebo for Emtricitabine<br>|
| Experimental: Placebo then TDF/FTC<br>For arm 2, half of the patients will receive placebo for the first 6 months of the study. There will be a one month washout period before starting on TDF/FTC (a combination of Tenofovir [TDF] and Emtricitabine [FTC]) for 6 months. | Drug: Tenofovir (TDF) and Emtricitabine (FTC)<br>* Tenofovir (TDF): a nucleotide reverse transcriptase inhibitor (NtRTI) an acyclic nucleotide analog of adenosine 5'-monophosphate. This is used in children as young as age 2. Emtricitabine (FTC): a nucleoside reverse transcriptase inhibitor (NRTI), a synthetic analog of cytidine which binds at the active site of the reverse transcriptase.<br>* Other names: Emtriva (Brand for emtricitabine);Other: Placebo<br>* Placebo for Tenofovir and Placebo for Emtricitabine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in interferon activation as measured by interferon response genes | The investigators propose to measure genes in the IFN stimulatory pathway in AGS patients, as a measure of disease activity and as a possible biomarker of therapeutic activity. Current data suggests that IFN related genes remain elevated in the late teens in AGS affected subjects, making it a more reliable measure of disease activity than IFN alpha. Validation of this preliminary data includes serial measurements in blood across several time points, to assess for variability. | From Baseline to 13 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determination of immune cell composition in CSF | The investigators will pursue immunophenotyping of CSF cells in AGS subjects. Immunophenotyping and target antigens will further understanding of end organ damage in AGS. Additionally, this may provide biomarkers for therapeutic outcome and disease activity. | From Baseline to 13 months | 
| Determination of immune cell composition in blood | The investigators will pursue immunophenotyping of peripheral blood monocytes in AGS participants. Immunophenotyping and target antigens will further our understanding of end organ damage in AGS. Additionally, this may provide biomarkers for therapeutic outcome and disease activity. | From Baseline to 13 months | 
| Accumulation of endogenous retroelements as measured in circulating immune cells | Performed by assays from previously collected samples | From Baseline to 13 months | 
| Accumulation of endogenous retroelements as measured in circulating CSF | Performed by assays from previously collected samples | From Baseline to 13 months | 
| Change in presence of non-specific and specific autoantibodies in blood | Performed by assays from previously collected samples | From Baseline to 13 months | 
| Changes in Adverse Events - Safety monitoring laboratory tests | Patient monitoring for adverse effects | From Baseline to 13 months and as clinically warranted | 
| Changes in total days hospitalized for disease-related illnesses. | Assess the effects of the treatment | Baseline - 13 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Leukodystrophy, Antiretroviral Drugs