Ophthalmology Update - Cleveland Clinic

i n v e s t i g a t i O n s
Second Intravitreal Implant Investigated
as Treatment for Uveitis
Corticosteroid treatment has long been a
mainstay of therapy for uveitis, and until recently,
most patients with vision-threatening
posterior, intermediate and panuveitis were
treated with systemic anti-inflammatory
therapy using corticosteroids and/or steroidsparing
immunosuppressive medications.
given the serious systemic side effects associated
with those modalities, the approval of the intravitreal
fluocinolone acetonide implant (retisert, Bausch
& lomb) for the treatment of chronic, noninfectious
posterior uveitis represented a significant advance
because it afforded long-lasting, effective disease
control without extraocular toxicity. nevertheless,
these benefits were not achieved without risks.
“in the premarketing clinical trials, nearly two-thirds
of patients who received the implant required
iOp-lowering treatment, about one-third had to
undergo glaucoma surgery and nearly all phakic
eyes developed cataracts that required removal,”
explains cole eye institute ophthalmologist careen
y. lowder, m.d., ph.d.
now, the cole eye institute is one of the clinical sites
participating in two recently launched multicenter
studies that are evaluating the efficacy and safety of a
dexamethasone posterior segment drug delivery
system (posurdex, allergan) for the treatment of
noninfectious anterior and intermediate uveitis.
dr. lowder and other investigators in those trials are
hopeful that this sustained-release corticosteroid
will also prove effective for reducing inflammation
while offering a better ocular safety profile than the
fluocinolone acetonide implant.
results of a phase ii trial investigating the dexamethasone
posterior segment drug delivery system
for the treatment of cystoid macular edema (cme)
provide evidence of its potential efficacy in the treatment
of uveitis, notes dr. lowder.
that study included 39 patients with cme associated
with uveitis. analyses of vision outcomes showed
that at 2 months after randomization, approximately
60% of patients who received the 350 or 700 µg dexamethasone
implant achieved a 10-letter-or-greater
improvement in best corrected visual acuity (Bcva)
compared with only about 21% of those in the
observation control arm. By 6 months after implantation,
42% of patients in the 350-µg implant group
and 46% of those in the 700-µg group maintained a
10-letter-or-greater improvement from baseline in
Bcva compared with only 21% of patients in the
observation group.
“in contrast to the fluocinolone device that released
corticosteroid for a period of almost 3 years, the bioerodable
dexamethasone implant was formulated
specifically for use in the eye and releases medication
for only about 3 months. We hope that duration
of treatment will be adequate to control the ocular
inflammation but be short enough that it will
be associated with lower risks of glaucoma and
cataractogenesis compared with the longer-lasting
fluocinolone implant,” dr. lowder says.
Both the anterior uveitis and intermediate uveitis
studies are masked, have a planned 26-week duration
and will randomly assign patients equally to
three arms to receive one of two doses of the dexamethasone
posterior segment drug delivery system
(350 µg and 700 µg) or sham treatment with a needleless
applicator system. the primary efficacy
assessment will be performed after 6 weeks in the
anterior uveitis study and after 8 weeks in the intermediate
uveitis study, and will be based on anterior
chamber cells (anterior uveitis) and vitreous
haze (intermediate uveitis) using standardized
grading scales.
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