Compositions, which are stable in storage, and a method of production of pharmaceutical based nanoparticulate formulations for clinical use in photodynamic therapy comprising a hydrophobic photosensitizer, poly(lactic-co-glycolic) acid and stabilizing agents are provided. These nanoparticulate pharmaceutical formulations provide therapeutically effective amounts of photosensitizer for parenteral administration. In particular, tetrapyrrole derivatives can be used as photosensitizers, whose efficacy and safety are enhanced by such nanoparticulate formulations. It also teaches the method of preparing PLGA-based nanoparticles under sterile conditions. In one of the preferred embodiments of the present invention PLGA-based nanoparticles have a mean particle size less than 500 nm and the photosensitizer is temoporfin, 5,10,15,20-tetrakis(3-hydroxyphenyl)-chlorin (mTHPC). In another embodiment, the photosensitizer 2,3-dihydroxy-5,10,15,20-tetrakis(3-hydroxyphenyl)-chlorin (mTHPD-OH) is formulated as a nanoparticle for parenteral administration. Yet, in another embodiment preferred photosensitizer is 5,10,15,20-tetrakis(3-hydroxyphenyl)-porphyrin (mTHPP). The formulations can be used for treating hyperplasic and neoplasic conditions, inflammatory problems, and more specifically to target tumor cells.
