[Solubilization Specificities Interferon beta-1b from Inclusion Bodies].

A new solubilization method of recombinant interferon beta-1b (IFNß-1b) from the inclusion bodies was developed. This method allows to extract the target protein selectively in the solutions of different alcohols, such as ethanol, propanol and isopropanol. It was shown that the more effective IFNß-1b solubilization was achieved in the 55% propanol solution. This method allowed to extract the target protein from inclusion bodies around 85-90%, and significantly reduced Escherichia coli content in the solubilizate, in comparison with standard methods.

[Recombinant granulocyte-colony stimulating factor (filgrastim): optimization of conditions of isolation and purification from inclusion body].

We developed a unified process platform for two recombinant human GCSF medicines--one with the non-prolonged and the other with prolonged action. This unified technology led to a simpler and cheaper production while introduction of the additional pegylation stage to the technological line eased obtaining of the medicines with different action and allowed to standardize technological process documenting according to GMP requirements.

[Recombinant granulocyte-colony stimulating factor (filgrastim): optimization of conjugation with polyethylene glycol].

In order to create an active pharmaceutical substance of the drug with prolonged action the modification of recombinant human granulocyte colony-stimulating factor GCSF (filgrastim) with polyethylene glycol (PEG, M 21.5 kDa) was conducted. A method for preparation of PEG-filgrastim designed for the development and scaling-up of the technological process of production was described. Modification of proteins with PEG was performed by selective covalent attachment of the molecule alpha-methyl-PEG-propionaldehyde to the alpha-amino group of the N-terminal methionine amino acid residue of the recombinant GCSF. The conditions of the reaction, which provide the desired product yield at least 85% of the total protein, also high protein concentration in the reaction mixture (more than 9 mg/mL) and reduce consumption of PEG in terms of terminal alpha-amino group of the protein was chosen. The data of RP HPLC and MALDI-mass spectrometry showed that the produced drug modified by the N-terminal residue and contains no more than 10% of products with a high degree of modification.

Toxicological studies of doxorubicin bound to polysorbate 80-coated poly(butyl cyanoacrylate) nanoparticles in healthy rats and rats with intracranial glioblastoma.

Polysorbate 80-coated poly(butyl cyanoacrylate) nanoparticles (NP) were shown to enable the transport of a number of drugs including the anti-tumour antibiotic doxorubicin (DOX) across the blood-brain barrier (BBB) to the brain after intravenous administration and to considerably reduce the growth of brain tumours in rats. The objective of the present study was to evaluate the acute toxicity of DOX associated with polysorbate 80-coated NP in healthy rats and to establish a therapeutic dose range for this formulation in rats with intracranially implanted 101/8 glioblastoma. Single intravenous administration of empty poly(butyl cyanoacrylate) NP in the dose range 100-400 mg/kg did not cause mortality within the period of observation. NP also did not affect body weight or weight of internal organs. Association of DOX with poly(butyl cyanoacrylate) NP did not produce significant changes of quantitative parameters of acute toxicity of the anti-tumour agent. Likewise, the presence of polysorbate 80 in the formulations was not associated with changes in toxicity compared with free or nanoparticulate drug. Dose regimen of 3x1.5 mg/kg on days 2, 5, 8 after tumour implantation did not cause drug-induced mortality. The results in tumour-bearing rats were similar to those in healthy rats. These results demonstrate that the toxicity of DOX bound to NP was similar or even lower than that of free DOX.

[Optimization of "Photosens" pharmakokinetics by biodegradable nanospheres]. / Optimizatsiia farmakokinetiki preparata "Fotosens" s pomoshch'iu biodegradiruemykh nanochastits.

The present study is dedicated to investigation of pharmacokinetics of the colloidal delivery system based on polybutylcyanoacrylate nanoparticles for the II generation photosensitizer Photosense. Free or nanoparticle-bound Photosense was injected intravenously in healthy rats in the dose 15 mg/kg. It was shown that pharmacokinetic curve of the free drug was characterized by peak concentration while plasma concentrations of nanoparticulate Photosense were relatively steady. Elimination of nanoparticulate Photosense was more rapid comparing to the free drug. It is noteworthy that nanoparticles did not enhance liver uptake of the drug. Lung level of nanoparticulate drug was found to be lower and spleen uptake was enhanced. More important is the fact that nanoparticles provided two-fold decrease of Photosense skin concentration which is potentially important for decrease of drug-related skin phototoxicity. The above data provide evidence that optimization of Photosense pharmacokinetic parameters could be achieved by the use of nanoparticles.