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Despite the rapid development of medical technologies, chemotherapy treatment still occupies an important place in clinical oncology. In this regard, the current research in this area focuses on the synthesis of new highly effective antitumor substances that have minimal side effects and the development of stable pharmaceutical formulations (PF) on their basis. In order to solve this problem, the I. Ya. Postovsky Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences actively sought for original substances, namely, nitrosourea (NU) derivatives, one of the most promising classes of anticancer drugs. As a result of this research, a novel NU derivative was synthesized, namely ormustine, which showed high antitumor activity in preliminary preclinical trials. It is now crucial to develop an ormustine pharmaceutical formulation. Conducted technological studies showed that the most suitable solvent for the drug substance is 0.1 M hydrochloric acid, which ensures its rapid dissolution by ultrasonic treatment. A significant reduction in the concentration of the active ingredient during the storage of the solution required the development of a technique of its lyophilization and the selection of a shaper such as a Kollidon 17 PF. Upon completion of the development of a pharmaceutical formulation of ormustine, its stability after lyophilization was demonstrated, and a sufficient amount of the drug has been acquired for preclinical research.

Background. In connection with the prospect of the use of an analog of the hypothalamic hormone somatostatin synthesized by the laboratory of chemical synthesis Institute of experimental diagnostics and chemotherapy of FSBI «N.N. Blokhin Russian Cancer Research Center» and showed a high anti-tumor activity as a drug arises a need to establish an optimal technology of its receipt. In preliminary studies in a modelformulation for an analog of the hypothalamic hormone somatostatin selected liposome technological process of which has a series of specific steps comprising. Objective. Development of technology for obtaining liposomal formulation hypothalamic hormone somatostatin analogue. Materials and methods. Liposomes analog of the hypothalamic hormone somatostatin obtained by method Bengema in modification for hydrophobic substances. To reduce the diameter of the liposome are used methods extrusion, homogenization and ultrasonic. Analysis of the size of the liposomes was performed by correlation spectroscopy light scattering using nanosizer. The pH of the liposomal dispersion was determined by potentiometry. The quantitative content of the drug substance was determined by spectrophotometry using a standard sample with X (282 ± 3) nm and an alcoholic solution of empty liposomes as a reference solution. Amount of incorporated drug was calculated as the ratio of the concentration of drug in the liposome dispersion after filtration to the concentration of drug in the dispersion after preparation. Results and Conclusion. The hydrophobic nature of the substance causes an analog of the hypothalamic hormone somatostatin technological features of obtaining liposomal formulation. Since the step of forming a film of the lipid substance is dissolved in an organic solvent together with lipids, film is hydrated by a solution of cryoprotectant. Grinding liposomes an analog of the hypothalamic hormone somatostatin appropriate to be carried out using homogenization or extrusion methods, due to the high efficiency of these methods, the preservation stability of the liposomes and a high percentage of inclusion an analog of the hypothalamic hormone somatostatin, included in the liposomal bilayer. At the stage of separating the non-inclusion of substance an analog of the hypothalamic hormone somatostatin due to the insolubility of the substance in the water, you can use the filtering method, without the need for complicated procedures gel filtration, dialysis, etc. Furthermore the process of separating a substance not included can be combined with the sterilization of the liposome dispersion by selecting a particular filter material.

Short Communications Despite a wide range of chemotherapeutic drugs used in actual therapy of malignant tumours, the main limitation of use in clinical practice is the expressed toxicity of most of these. There existed a need to search, study and develop dosage forms of drugs with high antitumor activity and low expressed side effects. Such dosage forms are needed to deliver analogues of a peptide hormone of hypothalamus, somatostatin, which inhibited release of human growth hormone, thyrotropin, glucagon, insulin, and also suppressed proliferation of many normal and tumor cells [1]. Analogues of somatostatin such as octreotide and lantreotide are under clinical investigation [2]. Indications for their use in oncology are, endocrine tumours of digestive tract and pancreas and therapy of androgen-independent prostate cancer. Thus, synthesis of new analogues of the somatostatin group, investigation of the mechanisms of action of their antiproliferative activities, and development of dosage forms are the new directions of research in this field.

The research is devoted to development and study of photosensitizers on a base of injectable nanoparticular formulations of phthalocyanine derivatives absorbing at long wavelength (near-infrared) range of 710-740 nm: Thiosens [liposomal form of aluminum hydroxide 1,8,15,22-tetrakis(phenylsulfanyl)phthalocyanine] and Octasens [polymeric micellar form of zinc 1 ,4,8,11,15,18,22,25-octachloro-2,3,9,10,16,17,23,24-octakis-(decylsulfanyl)phthalocyanine based on domestic poloxamer . Experiments have shown that the photosensitizers under study show high selectivity of accumulation and prolonged retaining at high concentration in tumor, relatively fast clearance from normal tissue and high therapeutic efficiency of photodynamic treatment on model tumors.