Visual acuity improved beyond that expected in relation to reduction in central macular thickness when a 2.5 mg dose of intravitreal ziv-aflibercept was used in patients with diabetic macular edema, according to a study.
CMT and BCVA were evaluated over the course of 1 year of treatment with 2.5 mg or 1.25 mg of intravitreal ziv-aflibercept (IVZ; Zaltrap, Regeneron) compared with 1.25 mg bevacizumab (IVB; Avastin, Genentech) in eyes with DME.
The study included 42 eyes in the 2.5 mg IVZ cohort, 42 eyes in the 1.25 mg IVZ cohort and 39 eyes in the IVB cohort, which respectively received 6.71, 6.67 and 11.56 mean number of injections.
The correlation of BCVA and CMT changes at all follow-up visits in the 1.25 mg IVZ cohort was statistically significant, compared with half the visits in the IVB cohort and none of the visits in the 2.5 mg IVZ cohort.
“Although positive correlation between VA improvement and CMT reduction has been reported in some studies, it has not been clearly demonstrated in some others, showing that anatomical improvement is not always associated with functional response,” the authors said. “Present findings show improvement in VA, which is beyond the concomitant macular thickness reduction in the eyes treated with 2.5 mg doses of ziv-aflibercept. This could be hypothesized by an assumed effect of higher concentration of ziv-aflibercept on macular perfusion,” the authors said. – by Robert Linnehan