Abstract
Purpose: :
The purpose of the study was to evaluate the correlation of the effective doses of clinically used anti-angiogenic ophthalmic drugs and those doses inhibiting angiogenesis in a novel in vitro assay. The assay is an intra-laboratory validated human cell culture assay with current applicability domain containing so far more than 30 different chemicals from clinical drugs and chemicals. The tested compounds included bevacizumab, ranibizumab and triamcinolone from which the effective dose data was available from controlled randomized clinical studies.
Methods: :
The angiogenesis fibroblast endothelial cell co-culture assay was established under Good Laboratory Practice. In the assay, the pre-vascular like tubule formation was induced with 10 ng/ml vascular endothelial growth factor (VEGF) and 1 ng/ml basic fibroblast growth factor. The cell assay was exposed to test drugs for six days, drugs applied to assay twice during the study. The tubule length and tubule branching were evaluated semiquantitatively under microscope by comparing to positive and negative controls at a predetermined scale.
Results: :
The VEGF-A antibody bevacizumab inhibited tubule formation significantly at ≥0.05 µg/ml (50% inhibition at 0.1 µg/ml), the high binding monoclonal VEGF-A antibody ranibizumab at ≥0.01 µg/ml (50% inhibition at 0.05 µg/ml), and triamcinolone acetonaide at ≥0.01 µg/ml (50% inhibition at 10 µg/ml).
Conclusions: :
The results obtained in this study show good concordance with the therapeutic vitreal concentrations reported in clinical trials of various retinal diseases, indicating that the effective concentrations of several angiogenesis-affecting chemicals can be reliably screened in this human cell culture angiogenesis assay. This is not only cost-effective and ethical step for the non-clinical phase of the development of new treatments for retinal disease but also accelerates this phase and drug discovery.
Keywords: drug toxicity/drug effects • vascular endothelial growth factor • neovascularization