The following drug information is obtained from various newswires, published
medical journal articles, and medical conference presentations.
Vitrasert has been approved for treatment of CMV in subjects
with AIDS. The implant releases ganciclovir to the site of disease
in the eye in which it is implanted.
The Vitrasert Implant, surgically placed in the posterior
segment of the eye, allows diffusion of drug (ganciclovir) locally
to the site of infection over an extended period of months.
Implantation normally takes less than one hour, requires only local
anesthesia, and is conducted in an outpatient, day-surgery
Immediately following insertion of the implant, most subjects
experience transient blurred vision in the operated eye, which
generally clears within two to four weeks. The implant can be
removed when depleted of drug, usually within five to eight months,
and a new Vitrasert Implant can be inserted.
Subjects with a Vitrasert implanted unilaterally should be
continuously monitored for the development of disease in the other
eye or for development of non-ocular CMV manifestations.
Data from Chiron Vision's phase III trial of 188 AIDS
subjects with newly diagnosed CMV retinitis have demonstrated that
time to disease progression was significantly delayed for subjects
who received Vitrasert, compared with those on intravenous (I.V.)
ganciclovir. The study showed that eyes in the primary analysis
group treated with Vitrasert had a median time to progression of
216 days, versus 104 days for eyes on I.V. treatment.
In addition, results of a clinical study reported by the
National Eye Institute (NEI) in the Archives of Ophthalmology
showed that the median time to progression of peripheral CMV
retinitis in newly diagnosed patients who received the implant was
about eight months, or 226 days. Those who received no immediate
treatment or those assigned to defer treatment progressed in
approximately 15 days.
CMV retinitis affects an estimated 15% to 40% of people with
AIDS. CMV retinitis usually begins as a white infiltrate within the
retina, and can progress rapidly to cause destruction of retinal
tissue. Retinal damage can lead to detachment of the retina,
occurring in 15% to 29% of subjects with AIDS-related CMV
retinitis, and permanent loss of vision.