Effects of Antiviral Therapies on Epstein-Barr Virus Replication

October 23, 2025 updated by: Michael, Levy M.D.,Ph.D., Massachusetts General Hospital
This research study is being performed to find out if Truvada (tenofovir/emtricitabine), an antiviral drug with activity against the Epstein Barr virus (EBV), can reduce EBV levels in saliva and blood in people with multiple sclerosis (MS). A second goal is to find out if Truvada (tenofovir/ emtricitabine) is safe and tolerable in people with MS.

Study Overview

Status

Enrolling by invitation

Conditions

Detailed Description

The proposed trial is built on the premise that multiple sclerosis (MS) is, in part, triggered by infection with the human herpesvirus Epstein Barr virus (EBV), and that targeting the virus could be a more effective and safer strategy for MS treatment than immunomodulation or immunosuppression alone. The evidence supporting a causal role for EBV in MS initially came from epidemiological studies that showed similarities in the distribution of infectious mononucleosis and MS, a 2-3 fold increased MS risk among individuals with a clinical history of infectious mononucleosis, and by compelling evidence that MS rarely, if ever, develops in individuals who are not infected with EBV. Furthermore, in a longitudinal study based on the Department of Defense Serum Repository with samples from over 7 million young adults free of MS, individuals who were EBV-seronegative at baseline did not develop symptoms of MS until at least several months after EBV seroconversion, and high serum antibody titers against the EBV-encoded nuclear antigen-1 were associated with an over 30-fold increase in MS risk.

Antiviral agents repurposed from treating other herpesviruses, like acyclovir or valacyclovir, have had minimal clinical efficacy against EBV in studies for infectious mononucleosis and multiple sclerosis. Prodrugs of tenofovir, such as tenofovir disoproxil fumarate (TDF), are significantly more potent inhibitors of EBV replication in cell culture than other drugs that have been clinically ineffective for EBV. TDF is a safe drug used clinically for HIV pre-exposure prophylaxis (PrEP) in HIV-negative patients as the drug Truvada. Truvada has been widely used since its approval in 2004 for the treatment of human immunodeficiency virus (HIV), and has a well-known safety profile that makes it a good candidates for clinical studies.

Study Type

Interventional

Enrollment (Estimated)

50

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Massachusetts General Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Provision of signed and dated informed consent form
  • Stated willingness and ability to comply with all study procedures and availability for the duration of the study
  • Age: 18+
  • Established diagnosis of multiple sclerosis
  • Evidence of Epstein Barr virus (EBV) infection by serological testing for EBV antibodies antibodies (subjects will have EBV testing performed at the pre-screening visit and if serologies are negative, the subjects will be removed from the study)

Exclusion Criteria:

  • Pregnancy or lactation
  • Known allergic reactions to components of Truvada
  • Previous treatment with Truvada or Descovy
  • Unknown HIV status (subjects must have completed HIV antigen/antibody and viral load testing within the prior 6 months to being enrolled or have the testing completed at the pre-screening visit)
  • Active or latent hepatitis B (HBV) (subjects must have completed HBV serologies - HbsAg, anti-HBs, and anti-HBc - within the prior 6 months to being enrolled or have the testing completed at the pre-screening visit)
  • Current symptoms of severe, progressive, or uncontrolled renal, hematologic, gastrointestinal, pulmonary, cardiac, or neurologic disease, or other medical conditions that, in the opinion of the investigator, might place the subject at unacceptable risk for participation in this study
  • Creatinine clearance (CrCl) <75mL/min, as calculated by the Cockcroft-Gault equation
  • Urine dipstick for protein and glucose, excluding values of "1 +" or greater
  • Any history of bone fractures not explained by trauma
  • Confirmed Grade 2 or greater hypophosphatemia
  • Any Grade 2 or greater toxicity on screening tests and assessments
  • Taking a medication with known interactions with Truvada including but not limited to: Acyclovir, valacyclovir, adefovir, cabozantinib, carbamazepine, cidofovir, cladribine, cobicistat, diclofenac, multiple non-steroidal antiinflammatories (NSAIDs) or chronic high dose NSAIDs, fosphenytoin or phenytoin, ganciclovir, valganciclovir, oxcarbazepine, phenobarbital, primidone, rifabutin, rifampin, rifapentine, sofosbuvir, tipranavir, or other drugs that significantly affect renal function
  • Current treatment with drugs known to affect EBV replication as listed below: Acyclovir, valacyclovir, ganciclovir, valganciclovir, famciclovir, teriflunomide, interferon

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Treatment arm
After a one-month baseline period where patients will not take any study drug, all patients will receive Truvada (tenofovir/emtricitabine) for three months. The study drug will be Truvada (tenofovir/emtricitabine), an antiviral drug that is approved by the Food & Drug Administration (FDA) for the treatment of chronic hepatitis B virus and for the treatment and prevention of human immunodeficiency virus (HIV) infection. The study drug will be administered at the standard dose used for the treatment and prevention of HIV (300mg tenofovir disoproxil fumarate, 200mg emtricitabine). Since extensive safety and tolerability data already exists for this standard dose, the selection of this dose also allows us to use existing data to inform strategies for safety and tolerability monitoring to minimize risk, as detailed in the study design.
Doses and route of administration of the study drug will be kept the same as for the FDA-approved indication of HIV-1 prevention in healthy individuals. The study drug is not FDA-approved for the treatment of multiple sclerosis.
Other Names:
  • TDF

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Epstein Barr virus (EBV) viral load
Time Frame: Change from baseline at three months
EBV viral load will be quantified in saliva and peripheral blood using a sensitive assay.
Change from baseline at three months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Tolerability of Truvada (tenofovir/emtricitabine)
Time Frame: Change from baseline at three months
Incidence of Treatment-Emergent Adverse Events [Safety and Tolerability]
Change from baseline at three months
Fatigue
Time Frame: Change from baseline at three months
Fatigue will be measured using a standardized survey scale where higher scores indicate more fatigue
Change from baseline at three months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Collaborators

Investigators

  • Principal Investigator: Michael Levy, MD, PhD, Massachusetts General Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

June 5, 2023

Primary Completion (Estimated)

June 4, 2026

Study Completion (Estimated)

December 31, 2026

Study Registration Dates

First Submitted

June 28, 2023

First Submitted That Met QC Criteria

July 14, 2023

First Posted (Actual)

July 24, 2023

Study Record Updates

Last Update Posted (Estimated)

October 27, 2025

Last Update Submitted That Met QC Criteria

October 23, 2025

Last Verified

October 1, 2025

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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