• Written By: Chirag P. Shah, MD, MPH

    The results of this 24-month proof-of-concept clinical trial suggest that oral doxycycline may be a promising treatment for the inflammatory component of diabetic retinopathy.

    To the author’s knowledge, this is the first study to suggest a link between a low-dose oral anti-inflammatory drug and subclinical improvement in inner retinal function in diabetic retinopathy.

    The authors randomized 30 patients with severe nonproliferative diabetic retinopathy or proliferative diabetic retinopathy without high-risk characteristics to low-dose oral doxycycline monohydrate (50mg daily) or placebo in a double-masked fashion.

    From baseline to month 24, retinal function, as measured by frequency doubling perimetry foveal sensitivity, increased in the doxycycline group (+1.8 dB) and decreased in the placebo group (‑1.9dB) (P = 0.02). This difference was detected at six months and persisted through the two-year study. There were no significant differences between groups in other visual function and anatomic outcomes assessed.

    Doxycycline was well tolerated, with minimal drug-related adverse events and no drug-related ocular adverse events.