Currently, two similar medications are available for injection into the eye to treat a variety of eye diseases. These medications are called ranibizumab (Lucentis) and bevacizumab (Avastin). They both have a similar mechanism of action and work equally well, however only ranibizumab was designed for use in the eye. It is significantly more expensive per injection than bevacizumab (by a factor of roughly 40x).

In published studies trends have been noted towards an increased rate of systemic side effects such as heart attacks and strokes. This is presumably due to absorption of the drug(s) from the eye into the bloodstream, however this has never been shown before. The purpose of the investigators study was to compare the bloodstream levels of bevacizumab and ranibizumab at various time points after injection into the eye. This required the creation of a sophisticated assay to measure blood levels of the drugs.

see above

Inclusion Criteria:

• patients in whom anti-vascular endothelial growth factor (VEGF) therapy is indicated for the treatment of diabetic macular edema
• able to return for extra clinic visits according to study schedule

Exclusion Criteria:

• active malignancy
• previous retinal laser treatment
• previous anti-VEGF therapy
• previous vitrectomy