Clinical Trial Details
— Status: Not yet recruiting
Administrative data
NCT number |
NCT04856397 |
Other study ID # |
00001 |
Secondary ID |
|
Status |
Not yet recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
May 25, 2021 |
Est. completion date |
December 29, 2021 |
Study information
Verified date |
May 2021 |
Source |
Uptown Eye Specialists |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The primary focus of this study is to understand the anatomic and visual outcomes of patients
with refractory and suboptimal treatment response diabetic macular edema (DME) using
anti-vascular endothelial growth factor (VEGF) to Ozurdex, an intravitreal dexamethasone
implant. Secondly, investigators aim to understand the differences in cytokine profiles in
patients who respond differently to intravitreal anti-VEGF versus Ozurdex. The importance of
this study is to identify biomarkers that may help predict patients' response to different
treatment protocols. Currently, Ozurdex is not covered by provincial health benefit plans for
patients with DME. Our results may help improve access to care for those who have suboptimal
results with or refractory to intravitreal anti-VEGF treatment.
Description:
Diabetic macular edema (DME) is the most common cause of vision loss in young patients with
diabetes. Its pathophysiology starts with decreased retinal oxygen tension that manifests as
retinal capillary hyperpermeability and increased intravascular pressure mediated by vascular
endothelial growth factor (VEGF) upregulation and retinal vascular autoregulation,
respectively. Spectral domain optical coherence tomography (SD-OCT) is the cornerstone of
clinical assessment of DME. The foundation of treatment is metabolic control of hyperglycemia
and blood pressure. Specific ophthalmic treatments of DME include intravitreal anti-VEGF drug
injections, in the form of intravitreal Bevacizumab (Avastin), Ranibizumab (Lucentis), and
Aflibercept (Eylea). Intravitreal corticosteroid injections, focal laser photocoagulation,
and vitrectomy are other treatment options. A substantial fraction of eyes respond
incompletely to all of these modalities resulting in visual loss and disordered retinal
structure and vasculature visible on SD-OCT and OCT angiography. There is currently no
consensus on when to switch from one treatment to another in the context of a suboptimal
response. Our hypothesis is that patients who are switched early to Ozurdex and achieve an
OCT proven dry state, achieve better functional outcomes than those patients who are switched
late or not at all, by limiting exposure of the retina to potentially damaging inflammatory
markers, and the merits associated with less frequent injections.
Suboptimal DME is defined as a central subfoveal retinal thickness of > 300 and the presence
of intra or sub-retinal fluid with a minimum BCVA of 20/25 or worse after 3 injections of
intravitreal aflibercept, from here on referred to as Eylea. Furthermore, there is some
evidence that a subset of patients with refractory DME respond well to intravitreal
corticosteroids, specifically, Ozurdex, which is a biodegradable, sustained-release
intravitreal dexamethasone implant, designed to be potentially injected between 2-6 months.
This medication is currently not covered by the Ontario health benefits plan for patients
with DME and comes at a significant cost to patients.
Moreover, recent studies have confirmed the important role of inflammatory ocular cytokines
in patients' response to intravitreal treatments in DME, much the same as neovascular
age-related macular degeneration. However, it is not known which ocular cytokines determine
the degree of response to various treatment modalities for DME.
Here, investigators aim to study the anatomic and visual outcomes, as well as the cytokine
profile of patients with suboptimal DME in response to early vs. late switch to intravitreal
Ozurdex treatment.