Combination therapy using verteporfin and ranibizumab; optimizing the timing in the CAM model.

Combining photodynamic therapy (PDT) using verteporfin (Visudyne) with ranibizumab (Lucentis) can optimize the overall treatment outcome by providing more efficacy in vessel closure, and thus reduce the need for retreatment in patients with wet age-related macular degeneration. In this preclinical study in the chorioallantoic membrane (CAM) of the chicken embryo, we compare the vascular occlusion effects of verteporfin and ranibizumab as monotherapies with those observed in the combined therapy. In order to optimize the combination therapy, we varied the timing and sequence of the PDT and antivascular endothelial growth factor modalities.

Effect of nanoparticle size on the extravasation and the photothrombic activity of meso(p-tetracarboxyphenyl)porphyrin.

Particle size should be optimized to achieve targeted and extended drug delivery to the affected tissues. We describe here the effects of the mean particle size on the pharmacokinetics and photothrombic activity of meso-tetra(carboxyphenyl)porphyrin (TCPP), which is encapsulated into biodegradable nanoparticles based on poly(d,l-lactic acid). Four batches of nanoparticles with different mean sizes ranging from 121 to 343 nm, were prepared using the emulsification-diffusion technique.

Encapsulation of porphyrins and chlorins in biodegradable nanoparticles: the effect of dye lipophilicity on the extravasation and the photothrombic activity. A comparative study.

In the present work, we performed a preclinical inter-comparison study using several photosensitizers with the goal of optimizing photodynamic therapy (PDT) for the treatment of choroidal neovascularization (CNV) associated with age-related macular degeneration. The tested molecules were the porphyrins meso-tetraphenylporphyrin (TPP) and meso-tetra-(4-carboxyphenyl)-porphyrin (TCPP), and the chlorins pheophorbide-a (Pheo-a) and chlorin e(6) (Ce(6)). Each of these molecules was entrapped in biodegradable nanoparticles (NP) based on poly(d,l-lactic acid).

Improved photodynamic activity of porphyrin loaded into nanoparticles: an in vivo evaluation using chick embryos.

Hydrophobic porphyrins are potentially interesting molecules for the photodynamic therapy (PDT) of solid cancers or ocular vascularization diseases. Their pharmaceutical development is, however, hampered by their lipophilicity, which renders formulation difficult especially when intravenous administration is needed. Encapsulation of a lipophilic derivative of porphyrin, the meso-tetra(p-hydroxyphenyl)porphyrin (p-THPP), into polymeric biodegradable poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles proved to enhance its photodynamic activity against mammary tumour cells when compared to free drug.