Abstract
Purpose :
The ocular tolerability and toxicokinetics of a suprachoroidal administration of CLS-TA, triamcinolone acetonide injectable suspension, in combination with an intravitreal injection of Eylea was evaluated in rabbits.
Methods :
Male and female New Zealand White rabbits (4/sex/group) were randomized according to body weight and assigned to eight treatment groups. On Day 0, each animal received a single bilateral intravitreal injection of either vehicle (50 µL) or Eylea (50 µL) followed 30 minutes later by a single bilateral suprachoroidal injection of vehicle (100 µL) or CLS-TA (100 µL). Of these animals, 4/sex/group were each necropsied on Day 1 and on Day 29. Clinical observations, body weight, slit lamp biomicroscopy, fundus evaluation, intraocular pressure assessment (IOP), electroretinography (ERG), and systemic exposure were assessed. Sacrified animals were assessed for macroscopic observations, ocular toxicokinetics and ocular histopathology.
Results :
There were no treatment or administration related effects on body weight, clinical observations, ophthalmic examinations or ERG. An increase in IOP was observed in the group treated with Eylea and CLS-TA, as well as in the groups treated with vehicle, but not in a pathological range. No treatment or administration related effects were observed at necropsy and there were no related adverse effects as assessed by histopathology on Day 1 and Day 29. Findings observed on Day 1 in individual animals treated with either CLS-TA or vehicle included conjunctival inflammatory cells and edema of the ciliary processes. These findings were not considered to be pathological since they were transient with minimal severity.
Data from systemic exposure as assessed by concentrations in plasma suggest that co-administration of CLS-TA and Eylea have no impact on the plasma pharmacokinetics of either drug.
Conclusions :
A single bilateral intravitreal injection of 2 mg Eylea (50 µL) followed by a single bilateral suprachoridal injection of 4 mg CLS-TA (100 µL) in albino rabbits was well tolerated. There were no treatment- or administration-related adverse effects by all evaluation methods. These findings support development of pharmaceutical therapies for retinal disease involving suprachoroidal administration including the use of combination of drugs.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.