Results of a prospective, double-masked, randomized study indicate that combination treatment with the dexamethasone implant 0.7 mg and laser photocoagulation is very well tolerated in patients with DDME and provides better functional and anatomic outcomes than laser treatment alone.
Dr. Kuppermann presented findings from the 12-month, phase II PLACID study that enrolled patients with diabetes aged 18 or more years with DDME-related retinal thickening, optical coherence tomography-measured central retinal thickness (CRT) ≥275 µm, and best-corrected visual acuity (BCVA) between 34 and 70 letters. He is professor of ophthalmology and biomedical engineering, University of California, Irvine.
Patients were randomly assigned 1:1 to combination therapy of dexamethasone implant plus laser (n = 126) or laser with sham implant (n = 127). Patients received the dexamethasone or sham implant on day 0 and laser photocoagulation 1 month later. Re-treatment with the dexamethasone implant was allowed no earlier than month 6, and up to 3 repeat laser treatments were allowed at intervals of no more than every 3 months.
The percentage of patients with a gain =10 letters in ETDRS BCVA at 12 months was analyzed as the primary efficacy outcome, and there was not a statistically significant difference between the combination and laser alone groups for this endpoint, 28% versus 24%, respectively.
However, in analyses of secondary efficacy outcome variables, there were significant differences favoring the combination dexamethasone implant plus laser group for having a greater percentage of patients with a 10-letter or better gain in BCVA at week 1 and months 1, 4, and 9 (3 months after the second injection); greater mean improvement from baseline BCVA at months 1, 4, 6, 7, and 9; and greater area under the curve for BCVA increase from baseline for the intervals from baseline to month 6 and baseline to month 12.
In addition, reduction in CRT was significantly greater in eyes treated with the combination regimen compared with laser alone at months 1 and 4, and the combination group also showed significantly greater reduction in area of diffuse leakage on fluorescein angiography at months 4, 6, 9, and 12.