BRPI1003297A2 - antineoplastic pharmaceutical compositions containing substituted nitroimidazole compounds - Google Patents

Abstract

ANTINEOPLASTIC PHARMACEUTICAL COMPOSITIONS CONTAINING REPLACED NITROIMIDAZOLOUS COMPOUNDS. The present invention describes antineoplastic pharmaceutical compositions containing substituted nitroimidazole. Since the compositions can be used in the treatment of neoplasms at an early stage or in combination with drugs with antitumor activity already established in more advanced stages of the disease.

Description

"ANTINEOPLASIC PHARMACEUTICAL COMPOSITIONS CONTAINING SUBSTITUTED NITROIMIDAZOLE COMPOUNDS"

The present invention describes antineoplastic pharmaceutical compositions containing substituted nitroimidazole compounds. The compositions may be used in the treatment of early stage neoplasms or in combination with drugs with antitumor activity already established in more advanced stages of the disease.

Solid tumors, such as lung, colon and breast carcinomas, are the main types of cancer in men. There is considerable evidence that the presence of hypoxic cells present in solid tumors may limit the effectiveness of radiotherapy. These same cells may also be resistant to many of the commercially available chemotherapeutic agents. However, this apparent obstacle can be explored for the design of agents with selective cytotoxicity for hypoxic cells (Cerecetto, H., Gonzalez, M., Lavaggi, ML Development of Hypoxia Selective Cytotoxins for Cancer Treatment: An Update. Med. Chem. 2, 315, 2006. Papadopoulou, V., Bloomer, WD Exploiting hypoxia in solid tumors with DNA-targeted bioreductive drugs Drugs Fut 29, 807, 2004. Wouters, BG, Weppler, S.A, Koritzinsky, M. , Landuyt, W., Nuyts, S., Theys, J., Chiu, RK, Lambin, P. Hypoxia as a target for combined modality treatments (Eur. J. Cancer. 38, 240, 2002).

In 1972, Lin and colleagues hypothesized that hypoxic cell regions could have a greater capacity for reduction than well-oxygenated cell regions. By analogy, hypoxic cells in solid tumors could exist in a microenvironment that would allow reductive processes to occur. Therefore, it was concluded that these characteristics of hypoxia cells could be explored in the development of chemotherapeutic agents, which would only become cytotoxic after metabolic activation. Thereafter, the concept of bioreductive activation of substances in hypoxia cells has been extensively studied (Dai, J., Liu, Y., Zhou, Y., Nagle, DG Hypoxia-selective antitumor agents: norsesterterpene peroxides from the marine sponge. Diacamus Ievii preferentially suppresses the growth of tumor cells under hypoxic conditions J. Nat. Prod. 70, 130, 2007. Lalani, AS, Alters, SE, Wong1 A., Albertella1 MR, Cleland1 JL, Henner, WD Selective tumor targeting bythe hypoxia-activated prodrug AQ4N blocks tumor growth and metastasis in preclinical models of pancreatic cancer Cancer Clin Res 13, 2216, 2007. Yamazakil, Y., Kunimoto1 S., Ikeda1 D. Rakicidin A. Hypoxia-Selective Cytotoxin. Pharm. Bull 30, 261, 2007. Anderson1 RF, Shinde1 SS, Hay1 MP, Gamage, SA, Denny1 WA Radical properties governing the hypoxia-selective cytotoxicity of 3-amino-1,2,4-benzotriazine antitumor 1,4 dioxides, Org. Biomol. Chem. 3, 2167, 2005).

The ability of nitroaromatics to act as bioreducible agents is already well established and therefore these compounds can be used as hypoxia cell selectivity prodrugs (Abreu, FC; Ferraz, PAL; Goulart, MOFJ. Braz. Chem. Soe (13, pp. 19-35, 2002; Hay, P., P. et al., J. Med. Chem., v. 38, pp. 1928-1941, 1995).

The concept of bioreductive activation of substances in hypoxic cells has been extensively studied (Dai, J. et al. J. Nat. Prod. V. 70, p. 130-133, 2007 .; Lalani1 AS et al. Clin. Cancer Res. V. 13, pp. 2216-2225, 2007.; Yamazaki, Y. et al., Hypoxia-Selective Cytotoxin., Biol. Pharm. Buli. V.30, pp. 261-265, 2007 .; Cerecetto, H. Gonzalez, M .; Lavaggi1 ML Med. Chem. V. 2, pp. 315-327, 2006) and it is noteworthy that two substances, tirapazamine and banoxantrone (AQ4N) are currently in the final stages of study. Screening Information (Novacea. About AQ4N. Available at: http://www.redorbit.com/news/health/1255929/novaceas_proofofprinciple_study of_aq4n_in_solid_tumors_published_in / index.html Accessed March 28, 2009, Marcu1 L .; Olver1 I. Curr Clin Pharmacol v. 1, pp. 71-79, 2006). Antitumor activity for hypoxic cells of nitrogen mustards derived from 2,5-dinitrobenzamide is also under investigation, with promising results (Atwell, GJ et al. J. Med. Chem. V.50, p. 1197-1212, 2007) .

In the late 1960s, Adams, Fowler, and colleagues first pioneered the use of high electron affinity compounds as radiosensitizers for hypoxia cells. Such compounds would have the ability to mimic the damaging effects of oxygen. Successful treatment of solid tumors using metronidazole confirmed this hypothesis. These compounds were developed as radiosensitizers, but it was subsequently shown that prolonged exposure of hypoxia cells to nitroaromatics results in selective cell death even in the absence of radiation.

Although nitroimidazoles such as metroimidazole and misonidazole have selectivity for hypoxic cells, they have low potency, and consequently high doses are required to exert a cytotoxic action. (Adams, GE; Br. Med. Bull 1973, 29, 48; Rauth, A.M; Kaufman, K.; Br, J. Radiat. 1975, 48, 209; Oliveira, RB; Alves, RJ Bioreducible Antineoplastic Agents: A New Alternative for the Treatment of Solid Tumors. (New Chem, 2002, 25, 976).

Kajfez et al described the synthesis of 2-methyl-4 (5) -nitroimidazole derivatives, including 1- (2-iodoethyl) -2-methyl-5-nitroimidazole with antitricomone activity (Kajfez, F .; Sunjic, V. ; Kolbah, D.; Fajdiga, T.; Oklobdzija, M. 1- Substitution in 2-methyl-4 (5) -nitroimidazole I. Synthesis of compounds with potential antitrichomonal activity J. Med. 167).

Busatti et al reported the effects of metronidazole analogs such as 1- (2-iodoethyl) -2-methyl-5-nitroimidazole (MTI) on Giardia lambia cultures (HG Busatti, Vieira, JC Viana, HE Silva , EM Souza-Fagundes, OA Martins-Filho, RJ Alves and MA Gomes, Parasitol Res. 2007, 102, 145).

Currently we find some patents available for the invention:

EP 866709 discloses a parenteral pharmaceutical composition containing tirapazamine for treating cancer, especially solid tumors, used alone or in combination with radiotherapy or other chemotherapeutic agents.

Patent application W02008118150 discloses a method for treating, preventing or ameliorating hyperproliferative disorders by determining the level of nitric oxide synthase in body fluids and the subsequent administration of bioreducible substances, including banoxantrone.

Although the treatment of cancer patients using hypoxic cell-selective bioreducible substances is under investigation, these substances are not yet commercially available. New options for substances showing selectivity for hypoxia and high potency tumor cells are important in an attempt to overcome the disadvantages of currently investigated options such as normal cell toxicity, inadequate physicochemical properties, and the need for association with classic antitumor drugs.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1: Structural formula of substituted nitroimidazole compounds

Figure 2: Structure of 1- (2-Iodoethyl) -2-methyl-5-nitroimidazole (MTI)

Figure 3: Pure MTI DSC (Differential Exploratory Calorimetry) Curve

Figure 4: DSC (Differential Exploratory Calorimetry) curve of the MTI: p-CD complex.

Figure 5: DSC (Differential Exploratory Calorimetry) curve of the physical mixture MTI: β-CD.

Figure 6: DSC (Differential Exploratory Calorimetry) curve of β-CD.

Figure 7: MTI solubility diagram: p-CD.

Figure 8: Comparison graph of tumor growth between control group and MTI at a dose of 40 mg / kg (n = 7).

Figure 9: Comparison graph of tumor growth between control group and MTI: ΗΡ-β-CD complex at a dose of 40 mg / kg (n = 5). DETAILED DESCRIPTION OF TECHNOLOGY

The present invention describes antineoplastic pharmaceutical compositions containing substituted nitroimidazole compounds having the structural formula of Figure 1.

Being the substituent "X" of Figure 1 selected from the group comprising I1 H, F, Cl, Br, OH1 N3, OPO3H1 OPO (OR) 2, NHR1NR2, NR3X1 OSO2R1 OSO2Ar1 OAr1 OCOR1 OCONHR1 SH1 SR1 SAr; where R may be H1 alkyl (C-2 to C-30.com or unbranched); aryl (aromatic or heteroaromatic); alkyl aryl (C-2 to C-30, with or without branching, aromatic or heteroaromatic).

The compositions of the present invention are characterized by the use of substituted nitroimidazole compounds combined with pharmaceutically acceptable excipients. Standard compositions may be liquid, solid or semi-solid. The liquid preparations may be in solution, suspension, emulsion, parenteral or oral form. Semisolids in the form of gels, ointments, creams or pastes and solids in the form of capsules, tablets, dragees or lozenges.

Examples of excipients include methylcellulose, hydroxypropylcellulose, hydroxyethylcellulose, carboxymethylcellulose, polymers derived from acrylic and methacrylic acid, polyethylene glycols, solid petroleum jelly, solid paraffin, Ianoline1 vegetable oils, mineral oil, cetyl alcohol, sterile alcohol, cetostearyl alcohol, glyceryl monostearate, cetyl esters, nonionic and anionic self-emulsifying wax and sodium lauryl sulfate, for semi-solid dosage forms.

Disintegrating binders1, diluents, lubricants, surfactants such as cellulose, lactose, starch, mannitol, magnesium stearate, talc, colloidal silicon dioxide, magnesium oxide and kaolin for solid preparations.

For liquid dosage forms solubilizers and surfactants such as glycerine, propylene glycol, sucrose, sodium lauryl sulfate and polysorbate may be used. For injections, water for injections may be used. Excipients may also contain minor amounts of additives such as isotonicity and chemical stability enhancing substances such as preservatives, chelators and stabilizers, examples of such substances include phosphate buffer, bicarbonate buffer and Tris buffer, thimerosal, m- or o-cresol, formalin, alcohol benzyl, parabens, EDTA1 BHA1 BHT; in addition to sweeteners, colorings and flavorings.

Such compositions may be administered intramuscularly, intravenously, topically, orally, by inhalation or as devices that may be implanted or injected. They can be used in the treatment of early stage neoplasms or in combination with drugs with antitumor activity already established in more advanced stages of the disease.

The present invention may be better understood by the following non-limiting examples of technology:

Example 1: Preparation and Characterization of MTI Inclusion Complexes: β-CD

A) Preparation of inclusion complexes

The MTI: β-CD inclusion complex was prepared by mixing β-CD and MTI (Figure 2) in water and acetone at a 1: 1 molar ratio. The mixture was stirred for 48 hours at room temperature. Subsequently, the acetone was evaporated and the resulting mixture was lyophilized. The lyophilized powder was kept in a desiccator under vacuum.

B) Characterization of inclusion complexes by differential exploratory calorimetry (DSC)

The 1: 1 β-CD-MTI inclusion complex, physical mixtures and pure MTI were characterized by differential exploratory calorimetry (DSC). In the DSC curve of free MTI (Figure 3) an endothermic event was observed at 101.20 ° C corresponding to the fusion of the MTI. In the DSC curve of the complex (Figure 4) no melting peak of the MTI was observed, indicating that it is within the DC cavity. The curve of the physical mixture (Figure 5) shows an endothermic event at 103.16 ° C corresponding to fusion of the MTI not found in the β-CD cavity. The broad peaks below 100 ° C that appear in the complex (Figure 4), physical mixture (Figure 6) and free β-CD curves (Figure 6) correspond to the elimination of water molecules present within the β-CD cavity. C) Solubility isotherm measurement

The concentration of soluble MTI at different concentrations of β-CD is illustrated in Table 1.

Table 1: Concentration of soluble MTI at different concentrations of β-CD.

<table> table see original document page 8 </column> </row> <table>

The inclusion complex MTI ^ -CD presented type B solubility diagram (Figure 7), that is, with the formation of low aqueous solubility complexes. In this diagram there is an initial increase in soluble MTI concentration with increase in CD concentration. After a maximum point, where the soluble concentration of free and complexed MTI is maximum, this concentration decreases with increasing concentration of cyclodextrin, by the formation of insoluble inclusion complex. Example 2: Evaluation of MTI's in vivo antitumor activity

A) Induction of Ehrlich ascites tumor in mice

For ascites tumor induction, three female Swiss mice weighing between 25 and 30 grams were used for each experiment. Ehrlich cells that were conserved in liquid nitrogen were thawed in a water bath at 37 ° C. They were transferred to a previously cleaned Falcon tube and 0.9% saline was slowly and gradually added thereto until the total cell suspension volume was approximately 20 ml. The suspension was immediately centrifuged for 5 minutes at 5 ° C and 3000 RPM speed. The medium in which the cells were conserved was removed as supernatant. The cells were resuspended with the aid of a Pasteur pipette in about 1.5 ml of 0.9% saline and then the cell concentration in the suspension was determined using the Neubauer chamber. The suspension was adequately diluted and 1x106 cells were injected intraperitoneally into each mouse in a total volume of 0.5 ml.

B) Ehrlich solid tumor induction in mice

Initially, 2 χ 106 Ehrlich tumor cells were taken from ascitic tumor mice and implanted in female Swiss mice, weighing 20 to 25 grams subcutaneously, dorsolaterally. After 10 days, the tumors were measured and the samples to be tested were administered intratumorally.

C) Evaluation of antitumor activity in mice

MTI was administered to a group of 7 animals at a dose of 40 mg / kg solubilized in saline containing PEG 400 (polyethylene glycol) (40%). The same number of animals was used in the control group. The 40 mg / kg MTI: β-CD complex was administered to 5 animals and the same number of animals were used as controls.

Doses were administered intratumorally twice a week for 3 weeks, with the exception of free MTI, whose treatment lasted 2 weeks. Tumor volumes (mm3) were calculated from measurements of their size (T) and width (L). Tumor volume was then determined using the formula T (L) 2/2 (Viale, M., Vannozzi, MO, Merlo, F., Cafaggi, S., Parodi, B., Esposito, M. Cisplatin Combined with the New Cisplatin-Procaine Complex DPR: In Vitro and In Vitro Studies (Eur. J. Cancer 1996, 32A, 2327). The animals had free access to water and feed and were kept in an environment with light cycle control.

Pure MTI showed antitumor activity when compared to the control group, as shown in the graph in Figure 8. The group treated with the MTI! Β-CD complex showed no significant improvement when compared to the group receiving pure MTI treatment (Figure 9).

Claims (7)

1. SUBSTITUTED NITROIMIDAZOls, characterized in that they have the following structural formula: <formula> formula see original document page 11 </formula> - X being selected from the group comprising I, H, F, Cl, Br, OH, N3, OPO3H1 OPO ( OR) 2, NHR1NR2, NR3X, OSO2R1 OSO2Ar1 OAr1 OCOR, OCON, OCONHR, SH, SR, SAr, where R may be H, alkyl (C-2 to C-30, with or without branching); aryl (aromatic or heteroaromatic); alkyl aryl (C-2 to C-30, with or without branching, aromatic or heteroaromatic). 2. ANTINEOPLASTIC PHARMACEUTICAL COMPOSITION, characterized in that it comprises substituted nitroimidazoles having the following structural formula: - X being selected from the group comprising I, H, F, Cl, Br1 OH, N3, OPO3H, OPO (OR) 2, NHR1NR2, NR3X1 OSO2R1 OSO2Ar , OAr, OCOR, OCON, OCONHR, SH1 SR, SAr, where R may be H, alkyl (C-2 to C-30, with or without branching); aryl (aromatic or heteroaromatic); (C-2 to C-30 alkyl aryl, with or without branching, aromatic or heteroaromatic), and - at least one pharmaceutically and physiologically acceptable excipient or adjuvant. ANTINEOPLASTIC PHARMACEUTICAL COMPOSITION according to claim 2, characterized in that the substituted nitroimidazole compounds are used in their free form, included or combined with cyclodextrins. ANTINEOPLASTIC PHARMACEUTICAL COMPOSITION according to claim 3, characterized in that cyclodextrins are selected from the group comprising α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin and derivatives thereof. ANTINEOPLASTIC PHARMACEUTICAL COMPOSITION according to Claims 1 to 4, characterized in that the substituted nitroimidazole compounds are used individually or in combination with other antineoplastic agents. ANTINEOPLASTIC PHARMACEUTICAL COMPOSITION according to Claims 1 to 5, characterized in that it is administered by oral, subcutaneous, intramuscular, intravenous, intraperitoneal, intratumoral, transdermal routes or as devices which may be implanted or injected. 7. USE OF REPLACED NITROIMIDAZOLE COMPOUNDS, characterized in being in the preparation of antitumor drugs.