CLT-003
CLT-003 is a small molecule that significantly reduces retinal vascular leakage and inflammation. CLT-003 has been formulated into nanoparticles (DD-001) to confer sustained efficacy through controlled and long-lasting drug release.
CLT-003 REDUCES RETINAL VASCULAR PERMEABILITY IN DIABETIC RATS
Adult rats were made diabetic with an injection of STZ, and blood glucose levels were monitored to ensure the rats entered a diabetic state. Following induction of diabetes with STZ, rats received an intravitreal injection of0.5, 0.75, or 1µg of CLT-003 in one eye and the vehicle in the contralateral eye as a control. After 2 days, the rats then received an intravenous injection of Evans Blue which was allowed to circulate and permeate into any tissues with nearby vascular leakage. Following retinal extraction, the level of Evans blue dye was quantified and normalized to the total protein isolated from each samples. CLT-003 reduced retinal vascular permeability in a dose-dependent mannerand the highest dose examined (1µg) reduced permeability to baseline levels observed in wild-type controls.
CLT-003 REDUCES RETINAL VASCULAR PERMEABILITY IN THE RAT MODEL OF OXYGEN-INDUCED RETINOPATHY
Newborn BN rats were exposed to 75% oxygen from age P7 to P12. The rats were then kept in room air for 4 days to allow partial formation of retinal neovascularization. At age P16 when retinal NV has formed partially, OIR rats received a single intravitrealinjection of0.5, 0.75, or 1µg of CLT-003 in one eye and the vehicle in the contralateral eye as a control. After 2 days, retinal vascular permeability was quantified using the Evans blue assay as described above. At doses of 0.75 and 1µg, CLT-003 dramtically reduced retinal vascular leakage, as compared to contralateral control eyes.
CLT-003 FORMULATED NANOPARTICLES CONFER SUSTAINED INHIBITION OF ENDOTHELIAL CELL PROLIFERATION
Bovine retinal capillary endothelial cells (BRCECs) were treated with 8, 16, or 32 µM CLT-003 or equal doses of CLT-003-Nanoparticles (CLT-003 NP). The cells were then incubated for 1, 3, 5, 7, or 9 days post administration and assayed for effects on cell proliferation (viability) by the MTT assay. The unpackaged CLT-003 showed strong inhibition with both doses on day 1, but viability gradually increased to nearly 100% by day 9. In stark contrast, the CLT-003 nanoparticles conferred sustained inhibition of endothelial cell proliferation out to day 9 post-administration.
CLT-003 NANOPARTICLES PRODUCE A SUSTAINED REDUCTION IN RETINAL VASCULAR LEAKAGE 2 WEEKS FOLLOWING INTRAVITREAL ADMINISTRATION
BN rats were made diabetic as described above and received an intravitreal injection of2, 4, or8µg of CLT-003 formulated nanoparticlesin one eye and the vehicle in the contralateral eye as a control. After 2 weeks, retinal vascular permeability was quantified. All three doses produced a significant reduction in retinal vascular permeability, with the 4 and 8 µg doses reducing permeability levels near to the baseline observed in non-diabetic rats.
INTRAVITREAL ADMINISTRATION OF CLT-003 NPS DOES NOT ELECTRORETINOGRAM AMPLITUDES AT 2-WEEKS POST-INJECTION
Electroretinograms were recorded from diabetic rats that were injected with 2, 4, or8µg of CLT-003 formulated nanoparticlesin one eye and the vehicle in the contralateral eye as a control. The scotopic a-wave amplitudes (a measurement of rod photoreceptor activity) was quantified and presented above. There was no statistical difference between any of the values obtained, demonstrating that CLT-003 NPs do not have a toxic effect on rod photoreceptor cells.
