Conditions: Diabetic Macular Edema
Keywords: Macular Edema Non steroidal anti-inflammatories
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 125
Healthy volunteers: no

Brief summary:
This study is being conducted to assess the effects of topical nonsteroidal anti-inflammatories (NSAIDs) on macular retinal volume compared with placebo in eyes with non-central diabetic macular edema (DME). A secondary objective of this study is to assess the effects of topical NSAIDs on central subfield thickness and to compare the progression of non-central DME to central DME as determined by optical coherence tomography (OCT) and stereoscopic fundus photographs. Furthermore, this phase II study is being conducted (1) to determine whether the conduct of a phase III trial has merit based on an anatomic outcome, (2) to estimate recruitment potential of a phase III investigation, and (3) to provide information on outcome measures needed to design a phase III trial. The study is not designed to establish the efficacy of NSAIDs in the treatment of non- central DME.

Detailed description:
There is strong evidence to indicate that prevention of non-central involved DME from progression into the central subfield of the macula is a good anatomic surrogate for preventing visual acuity loss. Furthermore, the prevalence of macular edema is estimated to be high among patients with diabetes, and it is likely that approximately 25% of non-central involved cases of DME extend into the central subfield of the macula within one year. Thus, if a relatively safe and economical treatment could be identified that reduced the progression of non-central involved edema to central-involved edema by at least 50%, this treatment could have a major public health impact.

There is also evidence that inflammation has a role in DME, and that a topical NSAID might have an effect on retinal edema. Topical NSAIDs are in current widespread clinical use and appear to be well tolerated and safe when administered chronically, making them a potentially attractive alternative treatment for DME in patients who would like to delay or avoid laser photocoagulation or intravitreal injections (for example, patients who are willing to use daily eye drops to avoid ocular procedures or patients for whom access to experienced retinal specialists to apply laser photocoagulation or other treatments is limited).

This phase II trial may provide proof of concept evidence that topical NSAID treatment can have a beneficial effect on DME and possibly prevent increases in retinal volume or progression of non central-involved DME into the central subfield of the macula. Furthermore, it could determine the correlation between OCT and fundus photographic documentation of progression of DME into the central subfield in this clinical trial setting. Since effective treatments, including laser photocoagulation and intravitreal injections, already exist for DME treatment, topical NSAIDs would have to demonstrate a substantial effect on DME progression in order to be of sufficient clinical interest for further investigation. If a beneficial effect is apparent in this trial, which utilizes a relatively small sample size and short follow-up period, results from this phase II study might be utilized in planning future phase III trials. These future phase III trials could definitively answer whether or not NSAIDs are an efficacious novel therapeutic approach to the treatment of DME or preventing the progression of DME from extending into the central subfield of the macula.

Arms:
arm 1: Placebo will be given three times per day for one year arm 2: Nepafenac drops will be given three times per day for one year

Interventions: intervention 1: nepafenac 0.1% drops intervention 2: Nepafenac Vehicle
Intervention descriptions: intervention 1: One drop three times per day for one year intervention 2: Placebo

Protocol document: