Gauging ganciclovir gel for herpes virus
Treatment has several clinical applications, but some research questions remain
Philadelphia—There is good evidence that topical ganciclovir gel (Zirgan, Bausch + Lomb) can help treat herpes simplex epithelial keratitis, said Kristin Hammersmith, MD.
There is also emerging evidence about the gel’s role in the treatment of other herpes viruses, including varicella zoster, cytomegalovirus, and adenovirus, according to Dr. Hammersmith, fellowship director, Cornea Service, Wills Eye Hospital, and associate professor, Thomas Jefferson University, Philadelphia.
The addition of ganciclovir gel to the treatment armamentarium in 2009 after FDA approval was welcome by ophthalmologists because of the side effects associated with other treatments, Dr. Hammersmith said.
“Over the last 50 years, we’ve had limited topical options for herpes keratitis,” she said.
Previous treatments have been associated with some risk for conjunctival inflammation and corneal erosion rates.
Ganciclovir works similarly as acyclovir. The agent is phosphorylated, contributes to less toxicity and is generally well tolerated. It also has a similar tonicity to tears and a long and stable shelf life.
The approved use is five times a day until the dendrite is healed and then three times a day for seven days.
Exploring use with other viruses
However, there is still plenty of room to explore how well it works to treat various herpes-related problems, Dr. Hammersmith noted.
The treatment appears effective for epithelial keratitis, Dr. Hammersmith said, citing evidence from four multicenter trials that looked at ganciclovir and acyclovir that found equal rates of recovery and healing times.
A Cochrane review article published last year analyzed 137 studies with more than 8,000 patients and found 29 studies that specifically used topical ganciclovir.1 Although the investigators concluded that ganciclovir was at least as effective as acyclovir for the treatment of epithelial keratitis, they added that any potential advantage was mitigated by study heterogeneity and possible publication bias.
There is also some evidence to measure the effect of ganciclovir after penetrating keratoplasty (PK).