BR132014031480E2 - USE OF THALIDOMIDE IN BROADCASTING RELEASE BIODEGRADABLE POLYMER SYSTEMS FOR CANCER TREATMENT - Google Patents

Abstract

The use of thalidomide in biodegradable polymer extended-release systems for cancer treatment This Certificate of Addition entitled “Thalidomide extended release device and use in eye diseases causing neovascularization” refers to the use of thalidomide drug incorporated into a polymeric system prolonged release biodegradable substance in the treatment of cancer, especially solid tumors.

Description

“USE OF THALIDOMIDE IN BIODEGRADABLE PROMOTIONAL RELEASE POLYMER SYSTEMS FOR CANCER TREATMENT” [001] Certificate of Addition of Invention of application BR1020120093162 filed April 20, 2012. The present invention relates to the use of the thalidomide drug, incorporated into a sustained release biodegradable polymeric system, in the treatment of cancer, especially solid tumors.

In many developed countries cancer is the second leading cause of death, falling behind cardiovascular disease. On the other hand, in less developed countries, epidemiological data point to the growth of cancer cases, making this a public health problem worldwide. The probable causes for this epidemiological transition are population growth and aging associated with lifestyle habits. The World Health Organization predicts that by 2030 there will be 11.5 million deaths from cancer worldwide and that the number of new cases this year will reach 15.5 million. Additionally, today more than half of all cancer cases occur in less developed countries or countries in transition in South America or Asia. (WORLD HEALTH ORGANIZATION. Are the number of cancer cases increasing or decreasing in the world? Available at: <http://www.who.int/features/qa/15/en/index.html>. Accessed on: Nov 6 2013.) A GfK Bridgehead Institute survey commissioned by GE Healthcare in May and June 2013 indicated spending of about $ 33.9 billion per year for cancer-related costs.

The second most common type of cancer in the world, breast cancer is the most common among women worldwide, accounting for 22% of new cases each year, with 1.38 million new cases diagnosed in 2008. About 75% of new breast cancer cases occur in developing countries. It is also the leading cause of cancer death in the female population, with more than half of deaths occurring in developing countries.

[004] Cancer treatment is by one or more combined modalities. The main one is surgery, which can be used in conjunction with radiotherapy and chemotherapy. Treatment is determined according to the location, type of cancer, and the extent or stage of the disease. In general, it is performed in schemes that combine different modalities and different drugs to ensure the elimination of different cancer cells (National Cancer Institute. Portal National Cancer Institute - INCA. Available at: <http: //www2.inca .gov.br / wps / wcm / connect / inca / portal / home> Accessed on: November 6, 2013, 2013).

Chemotherapy is the treatment with drugs, especially in cancer. Unlike surgery and radiotherapy, which are considered localized treatments, chemotherapy is usually a systemic treatment. This means that drugs are distributed throughout the body and reach cancer wherever it is located. Still, there are ways to limit the action of chemotherapy to one part of the body. (AMERICAN CANCER SOCIETY. Types of Cancer Treatment. Available at: <http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/index>. Accessed: 7 Nov. 2013).

Other drugs used to treat cancer are not included in the chemotherapy group. While the latter benefit from the rapid cell division observed in cancer cells, the others address different characteristics that differentiate tumors from normal tissues. (AMERICAN CANCER SOCIETY. Types of Cancer Treatment. Available at: <http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/index>. Accessed: 7 Nov. 2013).

Some therapies block or inhibit enzymes involved in signaling cancer cell growth. Thus, if they do not produce a tumor shrinkage, they at least reduce uncontrolled growth, which increases the chances of success of an associated chemotherapy. In addition, they may represent a survival gain for patients. They may also target proteins in cancer cells that induce apoptosis. Examples of such a group of substances include tyrosine kinase inhibitors, mTOR inhibitors, proteasome inhibitors, and growth factor inhibitors. (AMERICAN CANCER SOCIETY. Types of Cancer Treatment. Available at: <http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/index>. Accessed: 7 Nov. 2013).

Another alternative is drugs that stimulate the immune system to recognize and attack cancer cells, which is called immunotherapy, a relatively new option compared to other forms of cancer treatment. Different immunotherapies can be active (stimulating the patient's own immune system to fight the disease) or passive (administering components of the immune system to the patient, such as antibodies). Examples of immunotherapies include monoclonal antibodies (rituximab, alemtuzumab, etc.), non-specific and adjuvant immunotherapies (BCG, interleukin-2, interferon-alpha, etc.), as well as immunomodulatory drugs (thalidomide, lenalidomide, etc.) and vaccines.

New alternative technologies for treating cancer are also under development, such as the use of nanotechnology, stem cell transplantation, photodynamic therapy and the use of hyperthermia techniques, as well as the development of new drug delivery systems. (AMERICAN CANCER SOCIETY. Types of Cancer Treatment. Available at: <http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/index>. Accessed: 7 Nov. 2013).

[010] An interesting group of drugs used in cancer treatment are angiogenesis inhibitors. These prevent or reduce the formation of new vessels which is important for limiting nutrient supplementation to tumors that cannot grow (AMERICAN CANCER SOCIETY. Types of Cancer Treatment. Available at: <http://www.cancer.org / treatment / treatmentsandsideeffects / treatmenttypes / inde x> Accessed on: 7 November 2013).

[011] Among the substances researched as angiogenesis inhibitors used in cancer treatment, we can highlight bevacizumab. Bevacizumab is a humanized monoclonal antibody produced by recombinant DNA technology that, like ranibizumab, binds to all VEGF (endothelial growth factor) isoforms, thereby inhibiting their binding to their receptors on the surface of endothelial cells. (Food and Drug Administration. Department of Health & Human Sercice. AVASTIN® was approved for commercial marketing or use under § 351 of the Public Health Service Act on February 26, 2004. Rockville, MD, 2004, 9p. Available at: <http : //www.fda.gov/cder/foi/appletter/2004/125085ltr.pdf> Accessed 11 Mar 2011).

[012] This drug has been approved for the treatment of metastatic colorectal carcinoma, is used as a chemotherapeutic agent in various types of tumors, and phase 3 clinical trials are underway for other types of cancer such as lung, kidney and breast (PRASAD PS, SCHWARTZ SD, HUBSCHMAN JP Age-related macular degeneration: Current novel therapies (Maturitas, v. 66, pp. 46-50, 2010). However, systemic therapy is associated with an increased risk of thromboembolic events (Schouten JSA, La Heij EC, Webers CAB, Lundqvist IJ, Hendrikse F. A systematic review on the effect of bevacizumab in exudative age-related macular degeneration. Graefe's Archive of Clinical and Experimental Ophthalmology, v. 247, p. 1-11,2009).

[013] Despite advances in oncology in recent years, treatments have undesirable side effects and often poor therapeutic responses. Thus, there is an intense search for therapeutic alternatives with new drugs, new combinations or therapeutic regimens that can reduce undesirable effects and increase efficiency, supplanting the resistance mechanisms that are being observed in tumors (AMERICAN CANCER SOCIETY. Types of Cancer Treatment. Available at: <http://www.cancer.org/treatment/treatmentsandsideeffects/treatmenttypes/index> Accessed on: 7 November 2013.; GUPTA, SC; SUNG, B .; PRASAD, S .; WEBB, LJ ; AGGARWAL, BB Cancer drug discovery by repurposing: teaching new tricks to old dogs. Trends in pharmacological sciences, v. 34, no. 9, pp. 508-17, Sep 2013; OPREA, TI; MESTRES, J. Drug; repurposing: far beyond new targets for old drugs The AAPS journal, v. 14, no. 4, pp. 759-63, Dec 2012).

Thalidomide has been related to a number of biological effects (anti-inflammatory, immunomodulatory, anti-angiogenic, antitumor and apoptotic) with potential for the control or cure of different diseases. Thus, interest in its use as an antitumor agent has grown and several clinical studies are being conducted accordingly (EICHHOLZ, A.; MERCHANT, S.; GAYA, AM. Anti-angiogenesis therapies: their potential in cancer management. OncoTargets and therapy , v. 3, pp. 69-82, Jan 2010.; US NATIONAL INSTITUTES OF HEALTH Clinical Trials Available at: <http://clinicaltrials.gov/ct2/results?term=thalidomide&Search=Search>. Nov. 7, 2013).

Thalidomide (C13H10N2O4) is a synthetic isomerism derivative of glutamic acid (MELCHERT, M.; LIST, A. The thalidomide saga. The International Journal of Biochemistry & Cell Biology, v. 39, no. 7 8, pp. 1489-99, Jan 2007.). Due to its anti-angiogenic, anti-inflammatory and immunomodulatory properties, thalidomide has aroused the interest of the scientific community in recent years to have therapeutic effects in various diseases such as Kaposi's sarcoma in patients with AIDS, rheumatological diseases, Crohn's disease, cerebral malaria. , multiple sclerosis, psoriasis, sepsis, tuberculosis and some cancers.

[016] The main impetus in resuming interest in the use of thalidomide was the discovery of its angiogenesis inhibiting property. Cancer treatment can be directed to the stroma that supports tumor growth rather than directly to the tumor cells. Thalidomide has been shown to inhibit angiogenesis induced by basic fibroblast growth factor (bFGF) and endothelial growth factor (VEGF) (KENYON, BM; BROWNE, F .; D'AMATO, RJ. Effects of thalidomide and related metabolites in a corneal mouse model of neovascularization Experimental eye research, v. 64, no. 6, p. 971-8, Jun 1997.; KRUSE, FE; JOUSSEN, A ;; ROHRSCHNEIDER, K .; BECKER, MD; VOLCKER, HE Thalidomide inhibits corneal angiogenesis induced by vascular endothelial growth factor Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv für klinische and experimentelle Ophthalmologie, v. 236, no 6, p 461-6, Jun 1998 ).

[017] The inhibiting effect of angiogenesis by thalidomide is further described in US8039488 entitled "Methods and compositions for inhibiting angiogenesis" (D'AMATO RJ. Methods and compositions for inhibition of angiogenesis. Patent US8039488, 2011). In this patent it is shown that thalidomide and other related compounds, such as its precursors, analogs, metabolites and hydrolysis products, inhibited angiogenesis and were able to treat diseases resulting from angiogenesis.

New thalidomide-derived drugs (lenalidomide and pomalidomide), known as IMIDs, are being related to higher cancer-fighting potentials, with reduced adverse effects.

[019] In a study by Zhang et al. (2005), the effect of thalidomide on angiogenesis, tumor growth and metastasis of hepatocellular carcinoma in hairless mice was evaluated. It was observed that the VEGF level in the thalidomide-treated group was significantly lower than that of the control group and that thalidomide is capable of inhibiting angiogenesis and metastasis of hepatocellular carcinoma (ZHANG Z, LIU Z, SUN Q. Effects of thalidomide. on angiogenesis and tumor growth and metastasis of human hepatocellular carcinoma in nude mice World Journal of Gastroenterology, v. 11, pp. 216-220, 2005).

[020] Several doses and conditions are found to be employed in studies with thalidomide in animal models with cancer. These studies use oral or intraparenteral administration in immediate release forms as solutions using dimethyl sulfoxide (DMSO) or dimethylformamide (DMF), suspensions, or powders (GUIRGIS, A.A; ZAHRAN, M.AH .; MOHAMED, AS; et Effect of thalidomide dithiocarbamate analogs on the intercellular adhesion molecule-1 expression International immunopharmacology, v. 10, no. 7, p 80611, July 2010; (RUDDY, JMB; MAJUMDAR, SK Antitumorigenic Evaluation of Thalidomide Alone and in Combination with Cisplatin in DBA2 / J. Mice. Journal of Biomedicine & Biotechnology, v. 2, no. 1, pp. 7-13, Jan 2002).

Other formulations are described in the literature. These include classic formulations such as suspensions, but also others that target other forms of administration or changes in the bioavailability of thalidomide, such as liposomes, nanoparticles, and microparticles. These formulations seek to solve the problems of solubility, stability and adverse effects of thalidomide.

[022] Given its promising biological activities, unfortunately thalidomide has unfavorable physicochemical properties. It is a small molecule (PM 258 g / mol) with an asymmetric, polar center with low lipophilicity and has groups that can function as an acid or base in hydrogen bonds. Above that, it is highlighted that it is a very crystalline solid with high melting point and that has two polymorphs (alpha and beta). It is therefore practically insoluble in water and in many commonly used solvents, with an octanol / water partition coefficient log P 0,3. (GOOSEN, C.; LAING, TJ; DU, PJ; GOOSEN, TC; FLYNN, GL. Physicochemical characterization and solubility analysis of thalidomide and its N-alkyl analogs. Pharmaceutical research, v. 19, no. 1, p. 13- 9, Jan 2002). Also, their solubility in commonly used oils is less than 0.25 mg / g (ARAÚJO, F.A; KELMANN, RG; ARAÚJO, B.V; et al. Development and characterization of parenteral nanoemulsions containing thalidomide. sciences: Official Journal of the European Federation for Pharmaceutical Sciences, v. 42, no. 3, pp. 238-45, 14 Mar 2011). Its best solubility is found in solvents such as DMSO, DMF, dioxane and pyridine (UNITED STATES PHARMACOPEIA. Reference Tables: Description and Solubility - T Reference Tables: Description and Solubility - T. USP-NF. 29. ed. [Sl: sn] , 2005).

As a result of low solubility, the bioavailability of thalidomide after oral administration is limited as the drug is slowly absorbed from the gastrointestinal tract and may exhibit incomplete and erratic absorption (KALE, R .; TAYADE, P .; SARAF). , M .; JUVEKAR, A. Molecular encapsulation of thalidomide with sulfobutyl ether-7 beta-cyclodextrin for immediate release property: enhanced in vivo antitumor and antiangiogenesis efficacy in mice Drug development and industrial pharmacy, v. 34, no. 14956, Mar 2008). It is in class II of the biopharmaceutical classification system (SILVA, A.; MENEGHINI, L.; BAJERSKI, L. Discriminatory Dissolution Test for Tablets Containing a-and b-Thalidomide Polymorphs. Dissolutiontech.com, no. FEBRUARY, p. 19- 25, 2013). Thalidomide has Tmax (maximum time) in the body from 2.9 to 5.7 hours, with the area over the curve (AUC) proportional to the dose increase, but Cmax (maximum concentration) does not respond proportionally to the increase in dose. dose. Despite having different pharmacokinetic properties and activities, stereoisomers show interconversion in physiological environment catalyzed by serum albumin in humans (ERIKSSON, T .; BJORKMAN, S .; ROTH, B .; FYGE, A .; HOGLUN, P. Enantiomers of thalidomide. : blood distribution and the influence of serum albumin on chiral inversion and hydrolysis (Chirality, v. 10, no. 3, pp. 223-228, 1998).

In addition to the problems related to its solubility, thalidomide exhibits spontaneous and rapid hydrolysis at pH above 6, favored by its four amide bonds, which leads to the production of more than twelve degradation products (LEPPER, ER; SMITH, NF; COX, MC; SCRIPTURE, CD; FIGG, WD Thalidomide metabolism and hydrolysis: mechanisms and implications. Current drug metabolism, v. 7, no. 6, pp. 677-85, Aug 2006). In addition, thalidomide is also metabolised by cytochrome P450 (CYP450). Enzyme metabolism products are hydroxylated compounds, namely 5'-hydroxyitalidomide and 5-hydroxyitalidomide. On the other hand, pharmacokinetic studies have identified three human plasma hydrolysis products: α- (o-carboxybenzamido) glutarimide, 2-phthalimidoglutaramic acid and 4-phthalimidoglutaramic acid. These degradation products must have different activities. The two enzymatic metabolism products are often related to the antiangiogenic and antiproliferative effects of thalidomide.

In addition to the difficulties generated by its pharmacokinetics, we also highlight the serious adverse effects thalidomide presents, such as thrombovenous embolism, neutropenia, leukopenia, lymphopenia, anemia, thrombocytopenia, peripheral neuropathy, tremor, dizziness, paraesthesia, dysesthesia, drowsiness, constipation, peripheral edema and teratogenesis (EICHHOLZ, A.; MERCHANT, S.; GAYA, AM Anti-angiogenesis therapies: their potential in cancer management. OncoTargets and therapy, v. 3, p. 69-82, Jan 2010) . Such adverse effects limit their use, sometimes resulting in discontinuation of treatment, an important risk for cancer therapy (YAKOUB-AGHA, I.; MARY, J.-Y .; HULIN, C .; et al. Low-dose. versus high-dose thalidomide for advanced multiple myeloma: a prospective trial from the Intergroupe Francophone du Myélome (IFM) European journal of haematology, 25 Oct 2012). Especially because of the risk of neuropathogenicity, the lowest possible dose of thalidomide should be given, preferably once a day, at night because of its sedative effect (WANNMACHER, L. Return of Thalidomide: What is the Evidence? medications: selected topics, pp. 1-6, 2005).

[026] Assessed by the physicochemical characteristics, pharmacokinetics and adverse effects of thalidomide, the potential for improvement of thalidomide therapeutic response when administered as a polymeric implant for cancer treatment is noted.

[027] Biodegradable implants represent a potential pharmaceutical form in the treatment of tumors as they promote: (1) controlled release of the drug, enabling the maintenance of effective therapeutic levels over a prolonged period of time; (2) release directly to the site of action, avoiding side effects caused when administered systemically and protecting compounds from inactivation before reaching the site of action. These systems, because they are biodegradable, do not require surgical removal after complete drug release. They represent a therapeutic alternative, which has the advantage of avoiding weekly, daily or more frequent administration of the drug, allowing greater adherence to treatment (DASH, A.; CUDWORTH, G. Therapeutic applications of implantable drug delivery systems. Journal of pharmacological and toxicological, v. 12, no. 1998, pp. 1-12, 1998).

[028] Local application may increase drug concentration in target tissue, with likely efficacy gain. In addition, the time to drug exposure may also be increased. Substances whose activity is linearly related to concentration produce higher cell mortality when administered at high concentration. While drugs with exposure-related lethality potential produce better results in prolonged exposures. (PINTO REIS, C.; NEUFELD, RJ; RIBEIRO, AJ; VEIGA, F. Nanoencapsulation I. Methods for preparation of drug-loaded polymeric nanoparticles. Nanomedicine: nanotechnology, biology, and medicine, v. 2, n. 1, p 8-21, Mar 2006).

[029] The development of drug delivery systems is an area of innovation that includes the use of polymers. Macromolecules composed of repeated units linked by covalent bonds forming a chain, these compounds provide sustained and targeted release. (HASIRCI, V .; LEWANDROWSKI, K.; GRESSER, JD; WISE, DL; TRANTOLO, DJ Versatility of biodegradable biopolymers: degradability and an in vivo application. Journal of Biotechnology, v. 86, no. 2, p. 135- 50, 30 March 2001; PILLAI; PILLAI, O; PANCHAGNULA, R. Polymers in Drug Delivery (Current Opinion in Chemical Biology, pp. 447-451, 2001).

[030] Some polymeric systems, such as implants, micro and nanoparticles, have been proposed as pharmaceutical formulations. The biocompatibility of these systems refers to the ability of the material to produce an appropriate host response in a specific situation. This concept is related to the idea that the response produced should be evaluated according to the application and that the nature of that response to a specific material may vary in different situations. Especially in the case of biodegradable polymeric implants both polymer devices and degradation products must produce a satisfactory local and systemic response. In this sense, the polymers used in drug delivery systems must be chemically inert, non-carcinogenic, hypoallergenic and not causing intense inflammatory response at the application site (WILLIAMS, DF. On the mechanisms of biocompatibility. Biomaterials, v. 29, No. 20, pp. 2941-53, Jul 2008).

Drug delivery systems derived from synthetic biodegradable polymers generally use polyamides, polyamino acids, polyalkylcyanoacrylates, polyesters, polyorthoesters, polyurethanes and polyacrylamides (YASUKAWA, T .; KIMURA, H .; TABATA, Y .; OGURA, Y. Biodegradable scleral plugs for vitreoretinal drug delivery (Advanced drug delivery reviews, v. 52, no. 1, pp. 25-36, 31 Oct 2001). These biodegradable polymers are generally in the form of rods, discs or membranes (JAIN, RA). (Biomaterials, v. 21, n. 23) 2475-2490, 2000; KIMURA, H.; OGURA, Y. Biodegradable polymers for ocular drug delivery Ophthalmologica, v. 4678601, pp. 143-155, 2001 KLOSE, D.; SIEPMANN, F.; ELKHARRAZ, K SIEPMANN, J. PLGA-based drug delivery systems: importance of the type of drug and device geometry International journal of pharmaceutics, v. 354, no. 1-2, pp. 95-103, 16 Apr 2008).

PLGA or poly (glycolic lactic acid) is a copolymer used in various FDA approved therapeutic devices due to its biodegradability and biocompatibility. PLGA degradation occurs by cleavage of the polymeric chain by hydrolysis, releasing lactic and glycolic acid. The acids formed are the body's natural metabolites and can be eliminated by the Krebs cycle in the form of carbon dioxide and water (DINARVAND, R .; SEPEHRI, N .; MANOOCHEHRI, S .; ROUHANI, H .; ATYABI, F. Polylactide-co-glycolide nanoparticles for controlled delivery of anticancer agents, International Journal of Nanomedicine, v. 6, pp 877-95, Jan 2011).

Several PLGA and polymers derived therefrom can be found with different chain sizes, terminal groups, optical activity and with different proportions of lactic acid and glycolic acid monomers. They may be interspersed with other molecules such as polyethylene glycol and sugars. Such variations result in changes in physicochemical properties of this polymer, such as crystallinity and hydrophobicity (HASIRCI, V .; LEWANDROWSKI, K.; GRESSER, JD; WISE, DL; TRANTOLO, DJ. Versatility of biodegradable biopolymers: degradability and an in vivo application Journal of Biotechnology, v. 86, no. 2, pp. 135-50, 30 Mar 2001). Finally, there is a difference in the degradation time of the different copolymers. Thus, for example, the lactic acid polymer may have an increased degradation time when composed only of the L-isomer. Moreover, the 50:50 PLGA has different viscosities and end groups which may confer different characteristics to the products obtained from the product. of these.

[034] Although different drugs are currently being used and researched for cancer treatment, the potential and sometimes unknown adverse effects associated with these substances may make their clinical use difficult. For this reason, thalidomide has been of particular interest for use due to the extensive clinical experience surrounding its adverse effects and the literature describing its angiogenesis inhibiting property (ARAGON-CHING JB, DAHUT WL. VEGF inhibitors and prostate cancer therapy). Current Molecular Pharmacology, v. 2, pp. 161-168, 2009).

[035] Patent application BR1020120093160, entitled "Thalidomide prolonged release device and use in eye diseases causing neovascularization", refers to a device for the prolonged administration of thalidomide, which is incorporated in a monolithic system consisting of a Biodegradable polymer matrix of the polyester class. The device is preferably in the form of an implant and administration of this drug is preferably by intraocular route. This device can be used to treat eye diseases that cause neovascularization.

[036] However, to date the state of the art does not clearly describe the administration of thalidomide using a biodegradable prolonged release system with the possibility of reducing systemic adverse effects for the treatment of cancer. An alternative to this application is the use of thalidomide incorporated in formulation of polymeric systems in the form of implants.

[037] Thus, in the present technology a new use of the thalidomide system incorporated into a biodegradable extended release polymeric system (PLGA) has been demonstrated. The advantage of using this composition in cancer treatment is that it allows adjustments in drug concentration, the type of PLGA used, the size of the implant. Thus, there is the possibility of adjusting the dose and release rate of the active substance from the implant.

[038] The polymer used (PLGA) absorbs water and degrades, generating products that are absorbed by the body and is therefore a bioabsorbable polymer. The process of polymer degradation and drug release is quite slow, taking about two months to complete. Thus, after the implant is applied by minor surgical procedure or by means of an appropriate syringe, no further surgical removal is required. Implantation is performed parenterally, either subcutaneously or in a cavity or tissue adjacent to the tumor. Thalidomide may be administered using this biodegradable system with or without drugs of different pharmacological classes.

[039] Priority is given to assessing the effect on tumors that allow localized therapy, but the use of thalidomide implants in tumors that are not well delimited is not excluded.

DESCRIPTION OF THE FIGURES

[040] Figure 1 depicts the in vivo release profiles of PLGA implants containing 25%, 50% or 75% thalidomide (THD).

[041] Figure 2 is a photograph of micrographs of histological sections of the skin at the site of drug-free (a, b) or THD 75% w / w (c, d) implant placement. Highlighted are giant cells in the drug-free implant group (b) and inflammatory cells with nuclei in picnosis and cariorrexia in the implant group with 75% w / w THD (d).

[042] Figure 3 is a graph depicting sponge hemoglobin concentration removed from mice from control groups (CT) and implant-treated groups containing 75% THD (TT) after 7 and 10 days of implantation. Data represent mean ± SDR. * Values significantly different from negative control (P <0.05; unpaired t-test).

[044] Figure 4 is a graph depicting N-acetyl-bD-glucosaminidase (NAG) activity in the sponge removed from the control group (CT), and implant-treated groups containing 75% w / w THD following 7 days and 10 days of deployment. Data represent mean ± SDR. * Values significantly different from negative control (P <0.05; unpaired t-test).

Figure 5 is a graph depicting the effects of THD implants on Ehrlich tumor growth. Data represent the mean ± SDR (* P <0.05, t-Test).

DETAILED DESCRIPTION OF THE INVENTION

[046] The present invention is based on the use of thalidomide incorporated in a polymeric system compatible with parenteral application adjacent to the tumor in humans and other mammals, which drug may or may not be associated with other drugs.

[047] The present invention may be better understood by the following non-limiting examples: Example 1 - Preparation of the thalidomide-containing biodegradable system [048] For preparation of the implants, 10-75% thalidomide and 25-90 are initially weighed. 50:50% PLGA, which are solubilized in a mixture of acetonitrile and distilled water in an ultrasonic bath under heating at 3545 ° C. The obtained solution is immediately filtered using a 0.22pm sterile filter. The solution is frozen in liquid nitrogen. Then the solvent of the solution is removed by lyophilization. The obtained powder mixture is then used for the preparation of the implant by the hot molding method. Molding is carried out under pressure in the form of rods using heating at a temperature between 80 ° C and 110 ° C.

The obtained rods had an average weight of 3.5 to 4.5 mg, 3.0 to 5.0 mm in length and 0.9 to 1.2 mm in diameter.

Example 2: Evaluation of the in vivo release rate of thalidomide incorporated into the biodegradable systems developed in Example 1 after subcutaneous application [050] Female Swiss mice were anesthetized and a 0.5 cm to 1.2 cm incision was made and the skin was suspended with the aid of forceps with 25% w / w thalidomide or 50% w / w thalidomide or 75% w / w thalidomide implants. A previously weighed implant was inserted with forceps under the skin. The incision was closed by suture. At times 3, 7, 14 and 28 days, the animals were euthanized and the implants were recovered for quantitation of the remaining thalidomide by high performance liquid chromatography. [051] In vivo release profiles of PLGA implants containing 25%, 50% or 75% THD indicate a greater importance of burst release in formulations with higher drug concentrations (Figure 1).

Example 3: In vivo biocompatibility assessment of thalidomide incorporated into the biodegradable systems developed in Example 1 after subcutaneous application [052] Female Swiss mice received implants without thalidomide or with 25% w / w thalidomide or 50% w / w thalidomide or 75% w / w thalidomide by the surgical procedure described in Example 2. After 28 days, the skin of the animal in the region of the implant was sampled, at least 0.8 cm at 2, 0 cm for each direction from the implant. Histological sections (4 pm) of implant-containing skin samples were mounted on slides and stained with hematoxylin and eosin. The slides were evaluated by optical microscope.

[053] At the end of the third day after implant administration, macroscopically no process of rejection of the pharmaceutical form by animal tissues was observed. It was noted that the healing process continued without the presence of exudate or ulcerations. The same was found in subsequent time monitoring. There was also no weight loss or change in behavior.

[054] The area around the implant application site in vivo was clear. In the histopathological analyzes (Figure 2) of the skin removed from the implantation site, a layer of fibrous cells forming a capsule lining the cavity where the PLGA implant was isolated can be observed. Inside this capsule were observed immune cells that represent the body's response to the presence of the implant. Note the presence of lymphocytes, macrophages and giant cells, which characterize an inflammatory response to the foreign body. This inflammatory response was considered as a normal response without damage to the organism, which can be confirmed by the maintenance of body mass, as well as the behavior of mice and skin appearance at the implantation site during the testing period.

Example 4: Evaluation of in vivo antiangiogenic and antiinflammatory activity in a murine non-biocompatible sponge implantation model of thalidomide incorporated in the biodegradable systems developed in Example 1 [055] Female Swiss mice received implants with 75% w / w thalidomide by surgical procedure described in Example 2. Two groups (7 and 10 days after implantation) correspond to negative controls in which the thalidomide-containing implant was not included. In the treated groups (7 and 10 days) PLGA implants containing 75% w / w THD were added.

[056] Disc-shaped polyester-urethane sponges were used as a matrix for fibrovascular tissue growth. The mice received the sponges subcutaneously.

[057] Sponge vascularization was indirectly dosed by the amount of hemoglobin (Hb) using the Drabkin method (BELO et al. 2004; FERREIRA et al. 2007). Mononuclear cell infiltrate was quantified by measuring the level of activity of the lysosomal enzyme N-acetyl-b-D-glucosaminidase (NAG) that is present at high concentrations in activated magrophages.

[058] There was a significant reduction in hemoglobin concentration, which can therefore be considered as a reduction in the number of functional vessels in the sponge when implants containing 75% THD were applied (Figure 3). Thus, the THD delivered in these PLGA implants and released during the study period would be maintaining its antiangiogenic effect. Statistically significant difference was observed for the treated and control groups at both times.

[059] A statistically significant difference in NAG activity was found between the control group and the treated group after 10 days (Figure 4), indicating that thalidomide promotes regression in the inflammatory process involving mononuclear cell infiltrate, primarily activated macrophages. .

Example 5: Evaluation of in vivo antitumor activity in a solid Erlich murine tumor model of thalidomide incorporated into the biodegradable systems developed in Example 1 [060] Female Swiss mice were inoculated on the back with an injection containing 2.5 x 10 6 tumor cells. Ehrlich obtained from ascites in Swiss mice.

[061] Five days after tumor inoculation, the animals were divided into two groups of five animals in each: Group 1 (control) received drug-free PLGA implants; Group 2 (treated) received a PLGA implant containing 25% thalidomide. Sixty days after implantation the animals were sacrificed and the tumor was removed for volume measurement and histopathological analysis.

The thalidomide-containing implant was able to reduce tumor volume by 47% (P <0.05) (Figure 5).

Claims (3)

1. USE OF THALIDOMIDE IN EXTENDED RELEASE BIODEGRADABLE POLYMER SYSTEMS characterized by being in cancer treatment and the polymeric system preferably consists of a monolithic system composed of a biodegradable polymer matrix of the polyester class, preferably poly D, L-acid lactic-glycolic co-acid (PLGA). USE OF THALIDOMIDE IN EXTENDED RELEASE BIODEGRADABLE POLYMER SYSTEMS according to claim 1, characterized in that the polymeric system is preferably in the form of an implant. USE OF THALIDOMIDE IN EXTENDED RELEASE BIODEGRADABLE POLYMER SYSTEMS according to claims 1 and 2, characterized in that it is preferably for the treatment of solid cancer.