Purpose:
Polysorbate is a surfactant and emulsifier agent used in drug compounds commonly injected in the vitreous (e.g., Lucentis, Avastin, and Kenalog). It is also used in the preparation of new drugs for intravitreal injection. However, polysorbate retinal effects have not been published so far. The purpose of this study is to determine the electroretinographic and morphologic effects of polysorbate 80 on the rabbit retina after intravitreal injection. Polysorbate 80 is the component at the highest concentration used in the preparation of lipophilic drugs suspension.
Methods:
0.1 ml of polysorbate 80 (Tween 80, Sigma-Aldrich Inc, St. Louis, MO) was injected in the vitreous of 11 New Zealand rabbits. As control, contralateral eye of each rabbit was injected with the same volume of saline. Scotopic and photopic electroretinography (ERG) were recorded according to a modified ISCEV protocol before injection, and at days 7, 14, and 30. Slit-lamp and fundus exams were performed at all timepoints. Animals were sacrificed at day 30 and retina was analyzed by light microscopy.
Results:
Eyes injected with polysorbate 80 did not present clinical signs of intraocular inflammation. ERG records presented no changes in scotopic and photopic a- and b- waves amplitude and implicit time compared to baseline and saline-injected eyes (P>0.05, Sign test). Average data are shown in Table 1. No morphologic changes were found by light microscopy.
Conclusions:
Intravitreal injections of polysorbate 80 did not produce clinical, functional, or morphologic changes in rabbit retina. These data suggest that polysorbate 80 can be safely used on the preparation of drug compounds for intravitreal injection.
Keywords: drug toxicity/drug effects • electroretinography: non-clinical