A Novel Device for Suprachoroidal Drug Delivery to Retina: Evaluation in Nonhuman Primates.

Purpose: Evaluation of distribution and tolerance of suprachoroidal injection of indocyanine green (ICG) in nonhuman primates (NHPs) using a novel suprachoroidal (SC) delivery technology. Methods: Three live and three euthanized African green monkeys were injected with 150 or 200 µL ICG/eye into the SC space of both eyes, 2.5 mm posterior to the limbus in the inferior quadrant, utilizing a novel SC injector. Eyes were analyzed by imaging of scleral flatmounts. Live animals were observed for 24 hours for general health. Ophthalmic evaluation included slit-lamp biomicroscopy, tonometry, fundus imaging, confocal laser ophthalmoscopy, and spectral-domain optical coherence tomography (SD-OCT) before and at 10 minutes and 1, 3, and 24 hours post-injection. Results: SC dosing was successfully performed in all eyes. Infrared fundus imaging demonstrated ICG distribution throughout the posterior segment, reaching the macula within 24 hours post-injection. No inflammation, intravitreal penetration, SC blebs, retinal detachment, or hemorrhages were detected. No significant changes were observed in retinal thickness by SD-OCT (P = 0.267, ANOVA). A mild, statistically insignificant elevation in intraocular pressure was observed within 10 minutes post-injection (mean ± standard error: 7.28 ± 5.09 mmHg; P = 0.061) and was spontaneously resolved within the first hour after dosing. Conclusions: Suprachoroidal injection of 150 to 200 µL ICG dye was successfully performed and well tolerated in NHP eyes, with rapid distribution into the macular region and throughout the posterior pole. Translational Relevance: This novel SC drug delivery system may potentially provide safe and effective delivery of therapeutics to the posterior pole region in humans.

Efficacy and safety of dexanabinol in severe traumatic brain injury: results of a phase III randomised, placebo-controlled, clinical trial.

BACKGROUND: Traumatic brain injury is a major cause of death and disability. We sought to assess the safety and efficacy of dexanabinol, a synthetic cannabinoid analogue devoid of psychotropic activity, in severe traumatic brain injury. METHODS: 861 patients with severe traumatic brain injury admitted to 86 specialist centres from 15 countries were included in a multi-centre, placebo-controlled, phase III trial. Patients were randomised to receive a single intravenous 150 mg dose of dexanabinol or placebo within 6 h of injury. The primary outcome was the extended Glasgow outcome scale assessed at 6 months, with the point of dichotomisation into unfavourable versus favourable outcome differentiated by baseline prognostic risk. Prespecified subgroup analyses were defined by injury severity, recruitment rate, and time to dosing. Secondary analysis included control of intracranial pressure and quality of life. Analysis were prespecified in the protocol and the statistical analysis plan. This study is registered with ClinicalTrials.gov, number NCT00129857. FINDINGS: 846 patients were included in the efficacy analysis. The extended Glasgow outcome scale at 6 months did not differ between groups; 215 (50%) patients in the dexanabinol group and 214 (51%) patients in the placebo group had an unfavourable outcome (odds ratio for a favourable response 1.04; 95% CI 0.79-1.36). Improvements in the control of intracranial pressure or quality of life were not recorded and subgroup analysis showed no indication of differential treatment effects. Dexanabinol was not associated with hepatic, renal, or cardiac toxic effects. INTERPRETATION: Dexanabinol is safe, but is not efficacious in the treatment of traumatic brain injury.