Ocular Pharmacokinetics

Pharmacokinetic Simulations of Intravitreal Biologicals: Aspects of Drug Delivery to the Posterior and Anterior Segments

“…Our results support the view that intravitreal biologicals are eliminated nearly completely via the anterior route [7,9,25]. Some qualitative and outlier reports claim that biologicals are eliminated via the posterior route [26,27], but quantitative data and kinetic analyses show that anterior segment elimination of the biologicals is 4.5–50 times greater than the posterior elimination [8,19,25].…”

Pharmacokinetic Simulations of Intravitreal Biologicals: Aspects of Drug Delivery to the Posterior and Anterior Segments

“…Our results support the view that intravitreal biologicals are eliminated nearly completely via the anterior route [7,9,25]. Some qualitative and outlier reports claim that biologicals are eliminated via the posterior route [26,27], but quantitative data and kinetic analyses show that anterior segment elimination of the biologicals is 4.5–50 times greater than the posterior elimination [8,19,25].…”

Comparative Permeability of Human and Rabbit Corneas to Cyclosporin and Tritiated Water

“…The rapid penetration of human and rabbit corneas by water are consistent with results from a previous study and is indicative of the comparable rates of diffusion of this low molecular weight permeant through corneal epithelium, endothelium and stroma (37). However, our results do not confirm those from a more recent study which indicated that the permeability of the human cornea is lower than that of its rabbit counterpart (11). All enhancers used in the present study significantly increased CsA flux rates across fresh and frozen/thawed rabbit cornea compared to fresh and frozen/thawed tissue without enhancer over the entire course of the experiment, except in the presence of 20% Cremophor-EL where these differences became non-significant after 18 hours.…”

Pharmacokinetics of Pullulan–Dexamethasone Conjugates in Retinal Drug Delivery

“…and vitreal half-life (Figure 7) [49]. Location of pullulan conjugate in this plot, next t straight line of compounds with anterior elimination route, supports the notion tha conjugate is mainly eliminated via anterior route.…”

“…The simulated particle concentrations in the aqueous humor were close to the experimental values, indicating that practically all pullulan conjugates are eliminated from the vitreous via anterior route. Moreover, the Maurice plot (C v /C a vs. vitreal half-life) derived estimates of anterior elimination suggested that the major fraction (at least 82.7%) of intravitreally injected pullulan conjugate is eliminated via anterior route [49]. An anterior elimination route has been shown earlier for soluble macromolecules (e.g., antibodies) [57,58], but we have shown here for the first time that this route dominates the vitreal elimination of nanoparticles.…”

Pharmacokinetic Simulations of Intravitreal Biologicals: Aspects of Drug Delivery to the Posterior and Anterior Segments

“…Our results support the view that intravitreal biologicals are eliminated nearly completely via the anterior route [7,9,25]. Some qualitative and outlier reports claim that biologicals are eliminated via the posterior route [26,27], but quantitative data and kinetic analyses show that anterior segment elimination of the biologicals is 4.5–50 times greater than the posterior elimination [8,19,25].…”

Comparative Permeability of Human and Rabbit Corneas to Cyclosporin and Tritiated Water

“…The rapid penetration of human and rabbit corneas by water are consistent with results from a previous study and is indicative of the comparable rates of diffusion of this low molecular weight permeant through corneal epithelium, endothelium and stroma (37). However, our results do not confirm those from a more recent study which indicated that the permeability of the human cornea is lower than that of its rabbit counterpart (11). All enhancers used in the present study significantly increased CsA flux rates across fresh and frozen/thawed rabbit cornea compared to fresh and frozen/thawed tissue without enhancer over the entire course of the experiment, except in the presence of 20% Cremophor-EL where these differences became non-significant after 18 hours.…”

Pharmacokinetics of Pullulan–Dexamethasone Conjugates in Retinal Drug Delivery

“…and vitreal half-life (Figure 7) [49]. Location of pullulan conjugate in this plot, next t straight line of compounds with anterior elimination route, supports the notion tha conjugate is mainly eliminated via anterior route.…”

“…The simulated particle concentrations in the aqueous humor were close to the experimental values, indicating that practically all pullulan conjugates are eliminated from the vitreous via anterior route. Moreover, the Maurice plot (C v /C a vs. vitreal half-life) derived estimates of anterior elimination suggested that the major fraction (at least 82.7%) of intravitreally injected pullulan conjugate is eliminated via anterior route [49]. An anterior elimination route has been shown earlier for soluble macromolecules (e.g., antibodies) [57,58], but we have shown here for the first time that this route dominates the vitreal elimination of nanoparticles.…”

Pharmacokinetic Simulations of Intravitreal Biologicals: Aspects of Drug Delivery to the Posterior and Anterior Segments

“…Our results support the view that intravitreal biologicals are eliminated nearly completely via the anterior route [7,9,25]. Some qualitative and outlier reports claim that biologicals are eliminated via the posterior route [26,27], but quantitative data and kinetic analyses show that anterior segment elimination of the biologicals is 4.5–50 times greater than the posterior elimination [8,19,25].…”

Comparative Permeability of Human and Rabbit Corneas to Cyclosporin and Tritiated Water

“…The rapid penetration of human and rabbit corneas by water are consistent with results from a previous study and is indicative of the comparable rates of diffusion of this low molecular weight permeant through corneal epithelium, endothelium and stroma (37). However, our results do not confirm those from a more recent study which indicated that the permeability of the human cornea is lower than that of its rabbit counterpart (11). All enhancers used in the present study significantly increased CsA flux rates across fresh and frozen/thawed rabbit cornea compared to fresh and frozen/thawed tissue without enhancer over the entire course of the experiment, except in the presence of 20% Cremophor-EL where these differences became non-significant after 18 hours.…”

Pharmacokinetics of Pullulan–Dexamethasone Conjugates in Retinal Drug Delivery

“…and vitreal half-life (Figure 7) [49]. Location of pullulan conjugate in this plot, next t straight line of compounds with anterior elimination route, supports the notion tha conjugate is mainly eliminated via anterior route.…”

“…The simulated particle concentrations in the aqueous humor were close to the experimental values, indicating that practically all pullulan conjugates are eliminated from the vitreous via anterior route. Moreover, the Maurice plot (C v /C a vs. vitreal half-life) derived estimates of anterior elimination suggested that the major fraction (at least 82.7%) of intravitreally injected pullulan conjugate is eliminated via anterior route [49]. An anterior elimination route has been shown earlier for soluble macromolecules (e.g., antibodies) [57,58], but we have shown here for the first time that this route dominates the vitreal elimination of nanoparticles.…”