The study limitations included measurements obtained at only 4 points; the blood levels of the drugs were not measured; the assay might have interfered with the results and the drugs clear at different rates; and protocol T was not designed or powered to study systemic complications.
“At 4 weeks, the decreases in the VEGF levels were greater with aflibercept and bevacizumab compared with ranibizumab,” Dr. Jampol reported. “This remained true for bevacizumab at 1 and 2 years but not for aflibercept.
“In the pre-specified subgroups that did not receive an injection within 1 or 2 months before the 1-year time point, no differences in the VEGF levels were seen among the drugs,” he added. “In patients treated within 1 or 2 months before the 1-year visit, the VEGF decreases were less with ranibizumab than the other drugs.
Finally, Dr. Jampol noted that no data suggested that the VEGF plasma levels are related to the development of systemic complications. In the literature, there is little suggestion that plasma or serum levels are related to systemic adverse events.