Daniel Martin, an ophthalmologist at the Emory Eye Center and associate
professor with the Emory School of Medicine, was the lead investigator
in a clinical trial that has shown a new oral drug, Valcyte (valganciclovir),
is as effective as the previous intravenous treatment for the treatment
of cytomegalovirus (CMV) retinitis. The new finding was reported
in the April 11 New England Journal of Medicine.
CMV retinitis is a potentially devastating viral disease which
damages eyesight and can lead to blindness in patients with AIDS.
Once the condition is diagnosed, treatment can be lifelong, often
requiring long-term use of an indwelling catheter. As the first
potent oral treatment, Valcyte is more convenient for patients and
does not cause the problems that are associated with the use of
a chronic indwelling catheter.
This study demonstrates that Valcyte offers efficacy comparable
to that of Cytovene, the most widely used agent in induction therapy
for CMV retinitis, and does not require the use of a chronic indwelling
catheter which can be problematic for some patients, Martin
said. I expect that Valcyte will become a mainstay in the
treatment of AIDS patients with CMV retinitis.
Approved by the U.S. Food and Drug Administration in March 2001
for the induction and maintenance treatment of CMV retinitis in
patients with AIDS, Valcyte works by enhancing the absorption of
ganciclovir through the gastrointestinal tract. Once in the bloodstream,
ganciclovir enters cells infected with CMV and inhibits replication
of the virus. In patients who have CMV retinitis, Valcyte stops
viral replication, thus inhibiting further retinal damage, and preserving
In the study, 160 patients with AIDS and newly diagnosed with CMV
retinitis were randomly assigned to receive either Valcyte tablets
(900 mg taken orally twice daily for three weeks, followed by 900
mg once daily for one week maintenance therapy) or intravenous Cytovene
solution (5 mg/kg twice daily for three weeks followed by 5 mg/kg
once daily for one-week maintenance therapy).
After four weeks of treatment, results of both groups were evaluated
by masked review of retinal photographs. Results showed that after
four weeks of treatment with Valcyte, the number of patients whose
disease had progressed and the number of patients who had negative
CMV cultures and PCR were virtually identical to those treated with
Cytovene. In addition, the pharmacokinetic profiles for each treatment
were remarkably similar.
The most common adverse effect was diarrhea, which occurred more
often in the valganciclovir group (19 percent versus 10 percent
in the ganciclovir group). Intravenous catheter-related events occurred
in 9 percent of the IV ganciclovir patients and four percent of
valganciclovir patients (catheter present for other reasons).
CMV a member of the herpes family of viruses, infects approximately
50 to 75 percent of the U.S. adult population and 90 percent of
people with HIV. In individuals with healthy immune systems, CMV
exists in the body in a dormant state. However, among individuals
with compromised immune systems, the virus can become active and
cause disease. CMV retinitis, which damages eyesight and can cause
blindness, is the most common CMV-related condition in people living
with AIDS, affecting between 10 and 25 percent of persons with late-stage