To evaluate the safety and determine the efficacy of PRP monotherapy or combination therapy (pegaptanib 0.3 mg plus PRP) in patients with Type I or Type II diabetes mellitus and with high risk proliferative diabetic retinopathy.
Panretinal photocoagulation (PRP) can cause regression of retinal neovascularization and reduce the risk of severe vision loss in people with proliferative diabetic retinopathy (PDR). However, this destructive treatment may be associated with side effects (e.g. pain, transient blurring, loss of peripheral and/or night vision, increased risk of macular edema and central vision loss) and it is not always efficient in the regression of the neovascularization. Vascular endothelial growth factor (VEGF) has been shown to play a role in retinal neovascularization and retinal vascular leakage related with PDR and diabetic macular edema. Anti-VEGF treatments have been hypothesized as an adjunctive treatment for the management of retinal neovascularization and macular edema related with diabetic retinopathy (DR). Anti-VEGF agents, such as Macugen®, combined with PRP are expected to control neovascularization without the need for photocoagulation of the posterior pole, around the macula, thus avoiding the major side effects of standard PRP (visual field loss). A modification of panretinal photocoagulation (PRP) was recently proposed by Madeira et al., (2009) at the 2009 EURETINA Meeting. The described technique involves the progressive application of the DRS photocoagulation rings in a different sequence. First ring: corresponds to the DRS third ring, extruding from the ora serrata to the midperiphery. Second ring: corresponds to DRS second ring, extruding from the midperiphery towards the vortex veins. Third ring: corresponds to DRS first ring, and will only be performed if necessary. This technique resulted in less aggressive visual fields losses by achieving results with only most peripheral photocoagulation. The combination of intravitreal anti-VEGF treatment with pegaptanib, where a series of 3 injections are injected to reverse the neovascularization, while maintaining the macula dry will be completed by the more long term effect of the panretinal photocoagulation. This peripheral photocoagulation proposed is expected to eliminate the chronic VEGF stimulus by eliminating the chronic ischemic factor, while maintaining the visual fields useful for daily activities such as driving, etc.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
22
Panretinal Photocoagulation (PRP)
Intravitreous injection of pegaptanib
Center for Clinical Trials - Aibili
Coimbra, Portugal
Regression of retinal neovascularization
Retinal neovascularization will be measured in disc area units, and progression of neovascularization will be defined as an increasing of 0.5 disc area associated or not with vitreous haemorrhage, and/or pre-retinal haemorrhage, and/or rubeosis, and/or traccional retinal detachment.
Time frame: 12-month treatment
Changes from baseline in Best-Corrected Visual Acuity (BCVA)
BCVA will be assessed during the trial (Baseline, Month 3,Month 6, Month 12).
Time frame: 12-month treatment
Changes from baseline in macular retinal thickness by Optical Coherent Tomography (OCT)
OCT will be assessed during the trial (Baseline, Month 3, Month 6, Month 12).
Time frame: 12-month treatment
Changes from baseline in Visual Fields
Visual Fields will be performed during the trial (Baseline, Month 3, Month 6, Month 12).
Time frame: 12-month treatment
Recurrence of retinal neovascularization
To assess if there is recurrence of retinal neovascularization.
Time frame: 12-month treatment
Number of treatments needed
To analyse the number of treatments given to each subject during the 12-month treatment.
Time frame: 12-month treatment
Additional focal or grid laser for DME
To assess the number of subjects that received additional focal or grid laser for DME.
Time frame: 12-month treatment
Adverse events
Drug safety profile.
Time frame: 12-month treatment
Need for vitrectomy due to occurrence of vitreous hemorrhage or retinal detachment
To assess the number of subjects who needed vitrectomy due to occurrence of vitreous hemorrhage or retinal detachment.
Time frame: 12-month treatment
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.