Sustained anti-VEGF activity of aflibercept (Eylea^TM) after storage in polycarbonate syringes used for intravitreal injection: a pathway to safety and efficiency in high volume clinics providing intravitreal therapy.

Abstract

Purpose : Aflibercept (Eylea^TM, Regeneron) is supplied in single-use glass vials that are drawn into manufacturer-supplied 1 ml polycarbonate syringes. No studies of commercial aflibercept have assessed anti-VEGF activity more than 6 hours after storage in these syringes. We sought to determine if storage past this time would result in loss of anti-VEGF activity.

Methods : Aflibercept samples were drawn directly from commercially available glass vials into manufacturer-supplied 1 ml syringes (BD Luer-lok, cat no. 309628; Becton Dickinson), and stored at 4 degrees C. Anti-VEGF activity was assessed at the following storage durations: 0, 4, 9, 14, and 28 days. Frozen samples stored at -20 degrees C for 28 and 56 days were also assessed. Three samples at each time interval were tested and the experiment repeated. Also, a subset of aflibercept samples was stored and then diluted 1:10 in PBS. Recombinant human VEGF (rhVEGF; cat no. PHC9391, Fisher Scientific) was diluted with PBS containing 0.1% BSA to 100 ng/ml and was co-incubated with all Eylea samples for 30 minutes at room temperature. Samples were assayed for residual rhVEGF not bound to aflibercept using a Human VEGF ELISA Kit (cat no. KHG0111, Fisher Scientific).

Results : There were no statistical differences in anti-VEGF activity among any of the storage intervals for aflibercept samples stored at either 4 or -20 degrees C (see figure, p>.05, ANOVA, Tukey's multiple comparison). Samples diluted post-storage to 1:10 also showed no differences in activity.

Conclusions : Aflibercept stored in polycarbonate syringes, kept at 4 degrees C for up to 28 days, or at -20 degrees C for up to 56 days, retained anti-VEGF activity equivalent to freshly drawn aflibercept. Such sustained activity may facilitate earlier preparation of aflibercept syringes up to several days prior to use under pharmacy-based sterile conditions not present in most eye clinics, potentially providing greater safety and efficiency when large volumes of injections are performed.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.

 

Anti-VEGF activity of Eylea samples by storage temperature and duration, as shown by ELISA assay of unbound VEGF after 30 min incubation with stored Eylea samples. Lower unbound levels of VEGF indicate higher levels of anti-VEGF activity. Error bars are standard deviation.