Silicone oil droplets in repackaged anti–vascular endothelial growth factors for intravitreal injections: In search of the main source of contamination

INTRODUCTION: Repackaging of anti-vascular endothelial growth factors in polypropylene syringes lubricated with silicone oil for intravitreal use is associated with the presence of intravitreal silicone oil droplets. The objective of this study is to assess how the use of silicone-free syringes (for storage and/or administration) would reduce the amount of silicone oil droplets in the product to be administered. METHODS: Two 16 mL vials of bevacizumab were repackaged at the compounding pharmacy to obtain four sets of product, each consisting of three 1.2 mL tubes of the drug repackaged in different ways. Set A was repackaged according to routine practice, that is, the drug was placed into 1 mL siliconized syringes and 60 µL aliquots were extracted with 0.5 mL insulin siliconized syringes until reaching 1.2 mL. In set B, a 1-mL silicone-free syringe was used, followed by a 0.5 mL siliconized syringe. In set C, only 0.5 mL siliconized syringes were used. In set D, only the 1-mL silicone-free syringe was used. Micro-Flow Imaging technology was used for quantifying silicone oil droplet-like particles below 25 µm. RESULTS: Silicone oil droplet-like particles were absent in set D. Set C had the highest average frequency of these particles, which was much lower in sets A and B. Set B had the lowest frequency. CONCLUSION: 0.5 mL insulin syringes with staked-in needles used for supplying the product seem to be the main source of silicone oil contamination in repackaged anti-vascular endothelial growth factors. Silicone-free insulin syringes with staked-in needles would be strongly recommended for supplying anti-vascular endothelial growth factor intravitreal injections from compounding pharmacies.