Ischemic Central Retinal Vein Occlusion Clinical Trial
Official title:
Rubeosis Anti-VEGF (RAVE) Trial for Ischemic Central Retinal Vein Occlusion
The RAVE (Rubeosis Anit-VEgf) trial, utilizes monthly intravitreal Ranibizumab (Lucentis) injections for 9 months to see if total VEGF blockade will prevent neovascular glaucoma and eliminate the need for panretinal photocoagulation in patients with ischemic central retinal vein occlusion.
The most devastating complication of ischemic CRVO is the development of anterior segment
neovascularization and the resulting morbidity from neovascular glaucoma. This complication
appears to be directly correlated with intraocular VEGF levels. Currently there is no proven
treatment to decrease the formation of rubeosis. Current management of the disease consists
of pan-retinal photocoagulation once significant anterior segment neovascularization becomes
manifest. This treatment destroys peripheral retina (with peripheral retinal field) and
presumably works by eventually lowering ocular VEGF levels which causes secondary regression
of rubeosis.
As ranibizumab blocks VEGF, this treatment when delivered intraocularly may prevent
neo-vascular glaucoma while preserving peripheral visual fields in this patient population.
Risks of intravitreal injections are well known and include endophthalmitis and retinal
detachment. This risk should be less than 1% with proper injection technique and experienced
retinal surgeons. As the incidence of neovascular glaucoma (with resultant loss of central
and peripheral visual fields) is approximately 50% in ischemic CRVO, the small risk of
intravitreal injection is warranted if the drug shows efficacy. In a small number of
subjects in previous animal and human trials, intraocular pressure was acutely elevated when
the drug volume was placed intravitreally. An eye with a compromised circulation (such as
ischemic CRVO) may experience less perfusion if this occurred. Previous intravitreal studies
of ranibizumab have not utilized anterior chamber paracentesis to compensate for the volume
of intravitreal drug to be placed. This was reasonable because an eye with a normal retinal
circulation can tolerate relatively high intraocular pressure for a limited time. This
protocol for this study will include anterior chamber paracentesis prior to intravitreal
injection to minimize this potential risk.
;
Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment