Long-term, low-dose antiviral treatment may reduce the risk of potential vision loss related to shingles, according to researchers at the University of Pennsylvania and the NYU Grossman School of Medicine.

Shingles affects the eye in about 8% of the 1 million new cases in the United States each year. This is called herpes zoster ophthalmicus (HZO), which causes a painful eye infection and inflammation. A 7 to 10-day course of valacyclovir (Valtrex) is the standard of care treatment for acute cases of HZO. However, some patients will experience repeated flare-ups, leading to chronic eye disease, scarring, and ultimate vision loss.

This research, part of the larger 8-year Zoster Eye Disease Study (ZEDS), aimed to treat patients with low-dose valacyclovir for one year to improve overall outcomes and decrease complications of HZO. Researchers found this treatment could decrease the risk of new or worsening eye disease by 26% and reduce the incidence of recurrent flare-ups by 30% after 18 months. The ZEDS study also demonstrated patients on this treatment reported less pain associated with disease and required significantly less pain medication. Lead investigators presented these results at the Cornea Subspecialty Day at the American Academy of Ophthalmology earlier this month in Chicago.

“Up until now, there has been no proven long-term treatment for new, worsening, or repeated episodes of this disease, so the results of this study provide convincing evidence for using long-term, low-dose antiviral treatment,” Bennie Jeng, MD, director of the Scheie Eye Institute at the University of Pennsylvania and co-chair of the study, said in a recent Penn Medicine press release.  

The researchers showed that using valacyclovir for a year can decrease the risk of new or worsening eye disease by 26 percent at 18 months after initiating treatment. Patients treated with valacyclovir also were 30 percent less likely than those not receiving the treatment to have multiple HZO flare-ups at a year or a year-and-a-half later. 

“While our evidence in support of a new treatment regimen is vital, prevention is even more effective than any treatment,” Elizabeth Cohen, MD, professor of Ophthalmology at the NYU Grossman School of Medicine and study co-chair said. Dr. Cohen designed the study after she was, herself, affected by shingles-related vision loss. She said their goal was to explore longer-term treatment because, which standard treatment reduces the chances for chronic eye disease, there are still many people suffering from it.

“We hope that our work creates a relatively simple path toward preventing vision changes that can be life-altering,” Dr. Jeng said.