Zoster Eye Disease Study

Participants Screened

Participants Enrolled/Randomized



As of Dec-29-2017

What is the Zoster Eye Disease Study (ZEDS)?

  • A multi-center randomized clinical trial (RCT) to look at whether long-term treatment will be effective in decreasing eye disease and/or chronic pain in patients with a form of shingles, called Herpes Zoster Ophthalmicus, which affects the eye. Shingles, also called zoster, is caused by localized reactivation of the virus that causes chicken pox, known as the Varicella Zoster Virus.
  • The purpose of this study is to find out whether one year of a low dose of the oral antiviral medicine named valacyclovir reduces complications of shingles affecting the eye.
  • Patients who have had certain types of eye disease due to the shingles virus may be eligible to participate. These eye diseases include:
    1. Infection on the surface of the cornea, or the front of the eye.
    2. Inflammation and/or swelling, of the cornea.

Why is the Zoster Eye Disease Study (ZEDS) important?

Herpes Zoster Ophthalmicus (HZO), or shingles of the eye, may be associated with severe and long-lasting eye disease and eye pain.  Shingles of the eye may permanently damage how the eye works and may reduce quality of life for millions of Americans.

Shingles of the eye can happen to anyone who has had chickenpox. Most people in the USA age 40 years or older have had chicken pox, whether or not they know it. After a person has had chickenpox, the virus stays in the body and lays dormant (asleep) in the nerve cells. At some point later in life, the immune system may weaken, allowing the virus to become active again and cause shingles, sometimes in the eye and sometimes in other parts of the body. Shingles usually causes a painful rash with blisters on one side of the body. About a million people in the U.S. develop Shingles/ Herpes Zoster every year. Although the risk of shingles increases with age, the largest number of cases occurs in people in their fifties.

Chronic viral infection after an attack of shingles contributes to complications, including eye disease and rarely even stroke. Long-term low dose oral antiviral medication reduces recurrences of herpes simplex virus infections in the eye and elsewhere. The ZEDS study aims to find out if this treatment also works in reducing complications of shingles/zoster of the eye, which is caused by a different, but related, virus.

To contact the ZEDS Coordinating Center, please call 1-844-698-ZEDS(9337)

Frequently Asked Questions for Study Participants

  1. Why should I be part of this study?

    You have herpes zoster ophthalmicus (HZO), a form of shingles affecting the eye, and the purpose of this study is to find out if one year of low dose antiviral medication is effective in reducing complications.

  2. Why should I be part of this study if I can be treated with antiviral medications anyway?

    There is currently no good evidence that antiviral medications work to decrease complications for HZO, and the best way to find out is by randomly assigning study participants to the active antiviral study medication or a placebo that both look the same. If a study participant develops new or worsening eye disease, the doctor seeing them in the study can stop study medication temporarily or permanently and begin antiviral medication for a short or extended time, if he or she thinks it is indicated to treat the eye disease.  The study participant will continue with the follow-up visits in the study.

  3. Will I need more appointments?

    There are 8 study visits, some of which may coincide with when you would need to be seen to check your eye, if you were not in the study. Every effort will be made so that study visits are scheduled at a time that is convenient for you, and that you will not have to wait when you arrive. The visits have to be completed within a timeframe, but there is some flexibility in the timing of study visits, so they can be as convenient as possible for you.

  4. What if I don’t trust the idea of a research study and don’t want to be a guinea pig?

    Clinical studies are the way to find out what the best treatment is for many medical problems. Every effort is made so that participation in studies is safe. People who participate in studies often do better, probably because they are followed by their doctors more closely. Participation in ZEDS is especially safe because valacyclovir, the active study medication, has been approved by the FDA for over 20 years, including for long term treatment using a low dose for a related viral infection. In addition, study participants who have new or worsening HZO disease during the study can be taken off study medication, and be treated with antiviral medication.

  5. What can I do if I think the study medication capsule is too large?

    You can mix it with applesauce or yogurt to make it easier to swallow. However, you may not cut or crush the capsule.

  6. What if I had side effects to Valtrex when I was given it for treatment at the onset of zoster?

    The dose of active study medication used in ZEDS is much lower than the dose used for treatment. In addition, some forms of valacyclovir contain lactose, which can upset one’s stomach, but the study medication does not contain lactose. If side effects occur, the dose can be adjusted and reduced.

  7. If I have suffered a lot from having HZO, why should I want to be in a study?

    You will continue to get close follow-up care during the study. If you are not doing well on the study medication, it can be stopped temporarily or permanently while you are on a short or extended course of antiviral treatment.

  8. Can I get vaccinated against zoster and also participate in the study?

    Yes, you can do both! You can get vaccinated against zoster before or during the study. Vaccination against zoster with Shingrix is approved for adults age 50 years and older, including people with a past history or zoster, in order to prevent another episode in a different location. The timing of vaccination for people with HZO is not specified. Often vaccination of HZO patients is delayed until the eye disease is well controlled.

  9. What if it is easier for me to see my local eye doctor than the doctor in the study?

    You can see your local doctor between study visits, and have him or her send a copy of your record for the visit to the study doctor. You will need to see the study doctor, however, if you develop new or worsening HZO.

  10. What if I don’t speak English?

    The consent form to participate in the study is also available in Spanish, French, Chinese and Portuguese. We want very much for people from diverse backgrounds to participate!