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EGFR activation induces cell proliferation, neoformation of blood vessels, survival, and metastasis of the cancer cells. Nimotuzumab is an engineered, intermediate affinity anti-EGFR antibody, that apart from other drugs in its class, is very safe and does not cause hypomagnesemia or grade 3-4 cutaneous rash. The antibody inhibits cell proliferation and angiogenesis, activates natural killer cells, stimulates dendritic cell maturation, and induces cytotoxic T cells. Nimotuzumab restores MHC-I expression on tumor cells, hindering one of the EGFR immune-escape ways. The antibody has been extensively studied in 7 clinical trials, concurrently with irradiation or irradiation plus chemotherapy in subjects with inoperable head and neck tumors. Nimotuzumab was safe and efficacious in unfit patients receiving irradiation alone and in subjects treated with cisplatin and radiotherapy. In patients with locally advanced squamous cell carcinomas of the head and neck, nimotuzumab in combination with low dose cisplatin and radiotherapy was superior to cisplatin and radiotherapy in progression free survival, disease free survival, and locoregional tumor control.
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Finally, fast blood clearance nimotuzumab is a humanized monoclonal antibody that recognise, with high specific affinity, the epidermal growth factor receptor (EGF-R) which play an important role in the growth process associated with many solid tumors. In this work, the whole antibody was digested with papain in order to generate a Fab fragment, derivatized with NHS-HYNIC-Tfa and radiolabel with technetium-99m (99mTc) as a potential agent of molecular imaging of cancer. Both, whole and fragment radiolabels were in-vivo and in-vitro characterized. Radiolabeling conditions with Tricine as coligand and quality controls were assessed to confirm the integrity of the labeled fragment. Biodistribution and imaging studies in normal and spontaneous adenocarcinoma mice were performed at different times to determine the in-vivo characteristics of the radiolabel fragment. Tumor localization was visualized by conventional gamma camera imaging studies, and the results were compared with the whole antibody. Also, an immunoreactivity assay was carried out for both. The results showed clearly the integrity of the nimotuzumab fragment and the affinity by the receptor was verified. Fab(nimotuzumab)-HYNIC was obtained with high purity and a simple strategy of radiolabeling was performed. Finally, a fast blood clearance was observed in the biodistribution studies increasing the tumor uptake of Fab(nimotuzumab)- HYNIC-99mTc over time, with tumor/muscle ratios of 3.81 ± 0.50, 5.16 ± 1.97 and 6.32 ± 1.98 at 1 h, 4 h and 24 h post injection. Urinary excretion resulted in 32.89 ± 3.91 %ID eliminated at 24 h. Scintigraphy images showed uptake in the tumor and the activity in non-target organs was consistent with the biodistribution data at the same time points. Hence, these preliminary results showed important further characteristic of Fab(nimotuzumab)-HYNIC-99mTc as a molecular imaging agent of cancer.
Assuntos
Adenocarcinoma/diagnóstico por imagem , Anticorpos Monoclonais Humanizados/análise , Receptores ErbB/análise , Hidrazinas/análise , Imagem Molecular/métodos , Ácidos Nicotínicos/análise , Tecnécio/análise , Animais , Anticorpos Monoclonais Humanizados/metabolismo , Anticorpos Monoclonais Humanizados/farmacocinética , Receptores ErbB/metabolismo , Humanos , Hidrazinas/metabolismo , Hidrazinas/farmacocinética , Camundongos , Ácidos Nicotínicos/metabolismo , Ácidos Nicotínicos/farmacocinética , Papaína/metabolismo , Cintilografia/métodos , Tecnécio/metabolismo , Tecnécio/farmacocinética , Distribuição TecidualRESUMO
Objetivo: Valorar la importancia de la introducción de los estudios de evaluación económica en el desarrollo de los ensayos clínicos con productos biotecnológicos. Métodos: Se realizó una revisión bibliográfica para argumentar el valor que tiene la incorporación de los estudios farmacoeconómicos en las diferentes fases del desarrollo de un producto biotecnológico, como elemento fundamental para la búsqueda de eficiencia en la toma de decisiones en los sectores de la industria Biofarmacéutica y el Sistema Nacional de Salud. Resultados: La inserción de los estudios farmacoeconómicos en los ensayos clínicos con fármacos de producción biotecnológica es de vital importancia, ya que se podrá conocer si el fármaco es eficiente o no, decidir su inclusión en el cuadro básico de medicamentos, fijar su precio, así como, compararlo con las diferentes alternativas terapéuticas disponibles en el mercado y ayudar a determinar que opciones deberían emplearse de forma rutinaria, además de maximizar las oportunidades que estas nuevas terapias pueden ofrecer. Conclusiones: La inclusión de los estudios farmacoeconómicos en el desarrollo de los productos biotecnológicos, posibilitará incrementar la eficiencia, de forma tal que se prioricen y asignen los recursos necesarios de la industria Biofarmacéutica a las opciones terapéuticas que presenten mayores ventajas tanto económicas como sociales en términos de salud.
Objective: To assess the importance of the introduction of economic evaluation studies in the development of clinical trials with biotechnology drugs. Methods: A literature review was conducted in order to argue the value of incorporating pharmacoeconomic studies in the different phases of a biotech product development as a key element in the search for efficiency in decision-making in the Biopharmaceutical industry and the National Health System. Results: The insertion of the pharmacoeconomic studies in the clinical trial with biotech drugs is very important, because they will permit to know if the drug is efficient or not, their inclusion in the drug scheme, their price, as well as, to compare it with the different therapeutic alternatives available in the market and to determine the therapeutic options that should use in routine medical practice and maximize the opportunities that these new innovative drugs can offer. Conclusions: The inclusion of pharmacoeconomic studies in the development of biotech product will enable increased the efficiency, as well as, to prioritize and allocate the necessary resources of Biopharmaceutical industry to the therapeutic options with greatest economic and social advantages.
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In this work Nimotuzumab (monoclonal antibody, recognizes the EGF-R) was radiolabeled with (177)Lu as a potential cancer therapy radiopharmaceutical. In-vitro cell binding studies and in-vivo biodistribution and imaging studies were performed to determine the radiochemical stability, targeting specificity and pharmacokinetics of the (177)Lu-labeled antibody. Nimotuzumab was derivatized with DOTA-NHS at room temperature for 2 hours. DOTA-Nimotuzumab was radiolabeled with (177)LuCl3 (15 MBq/mg) at 37°C for 1 h. The radiochemical purity was assessed by ITLC, silica gel and by RP-HPLC. Binding specificity studies were performed with EGF-R positive A431 human epithelial carcinoma and EGF-R negative MDA-MB-435 breast carcinoma cells. Biodistribution studies were performed in healthy female CD-1 mice at 1 h, 4 h, 24 h, and A431 xenografted nude mice at 10 min, 1 h, 4 h, 24 h, 48 h, and 96 h. SPECT-CT imaging studies were performed in A431 xenografted mice at 24 h post injection. DOTA-Nimotuzumab was efficiently labeled with (177) LuCl(3) at 37°C. The in vitro stability of labeled product was optimal over 24 h in buffered saline and mouse serum. Specific recognition of EGF-R by (177)Lu-DOTA-Nimotuzumab was observed in A431 cell binding studies. Biodistribution studies demonstrated increasing tumor uptake of (177)Lu-DOTA-Nimotuzumab over time, with tumor to muscle ratios of 6.26, 10.68, and 18.82 at 4 h, 24 h, and 96 h post injection. Imaging of A431 xenografted mice showed high uptake in the tumor. (177)Lu-DOTA-Nimotuzumab has the potential to be a promising therapy agent, which may be useful in the treatment of patients with EGF-R positive cancer.
Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Compostos Radiofarmacêuticos/farmacologia , Animais , Anticorpos Monoclonais Humanizados/farmacocinética , Antineoplásicos/farmacocinética , Estabilidade de Medicamentos , Receptores ErbB/metabolismo , Feminino , Fígado/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias/metabolismo , Octreotida/análogos & derivados , Octreotida/farmacocinética , Octreotida/farmacologia , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/farmacologia , Compostos Radiofarmacêuticos/farmacocinética , Baço/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único , Transplante Heterólogo , Células Tumorais CultivadasRESUMO
Los anticuerpos monoclonales y sus fragmentos marcados se han empleado ampliamente en el diagnóstico y seguimiento de diferentes tipos de neoplasias. El objetivo del trabajo fue desarrollar una metodología para el marcaje indirecto de anticuerpos con 99mTc, partiendo de la N2-dietilentriamino-pentaacetil lisina amida como agente quelatante. Mediante reacción con un exceso molar de 2-iminotiolano (1:200) y reducción con un exceso de 2-mercaptoetanol (1:2000) se generaron en el anticuerpo 3.5 +/- 0.6 y 5.8 +/- 0.5 grupos SH, respectivamente, por lo que se continuó el trabajo con la segunda metodología. Se incubó el h-R3 reducido durante 12 h con N6-ciclohexilmaleimido-N2-dietilentriaminopentaacetil lisina amida, obtenida previamente mediante la reacción de la N2-dietilentriamino-pentaacetil lisina amida con sulfosuccinimidil4(N-maleimido-metil) ciclohexano-1-carboxilato de sodio. La eficiencia de marcaje con 99mTc del anticuerpo monoclonal h-R3 modificado según este método fue de (98.6 +/-1.4) por ciento, manteniendo una estabilidad satisfactoria hasta 24 h frente al exceso de L-cisteína (1:300). Conclusiones: La metodología desarrollada permitió el marcaje indirecto del anticuerpo monoclonal humanizado h-R3 con 99mTc de forma satisfactoria, empleando la N2- dietilentriaminopentaacetil lisina amida como agente quelatante bifuncional.
Labeled monoclonal antibodies and their fragments are been widely employed for the diagnosis and follow up of different kinds of neoplasm. The aim of the present work was to develop a method for indirect labeling of antibodies with 99mTc, using N2-diethylentriamine-pentaacetil lysine amide as chelating agent. By reactions with a 200-fold molar excess of 2-iminothiolane, and the reduction using a 2000-fold molar excess of 2-mercaptoethanol, 3.5 +/- 0.6 and 5.8 +/- 0.5 sulfhydril groups, respectively, were generated in the antibody. Thus, work was continued using the second procedure. Reduced h-R3 was incubated for 12 h with N6-cyclohexylmaleimide-N2-diethylentriamine-pentaacetil lysine amide, previously obtained by the reaction of N2-diethylentriamine-pentaacetil lysine amide with sodium sulfosuccinimidyl4(N-maleimidomethyl)cyclohexane-1-carboxylate. Labeling efficiency of h-R3 monoclonal antibody, modified by this method with 99mTc, was (98.6 +/- 1.4) percent. A satisfactory stability of the label was observed up to 24 h in presence of a 300-fold molar excess of L-cysteine. Conclusions: Developed procedure allowed satisfactory indirect labeling of the humanized monoclonal antibody h-R3 with 99mTc, using N2-diethylentriamine-pentaacetil lysine amide as bifunctional chelating agent.
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Humanos , Anticorpos Monoclonais , Marcação por Isótopo/métodos , Tecnécio , Quelantes , Estabilidade de Medicamentos , Fatores de TempoRESUMO
UNLABELLED: Monoclonal antibody (mAb) ior c5 is an IgG1, which recognizes a glycoprotein tumor specific antigen IOR C2 over expressed in the surface of colon and ovarian cancer cells. The aim of the present work was to evaluate the diagnostic efficacy of the 99mTc-labeled mAb ior c5 for the detection of colorectal tumors, its metastases and recurrences. METHODS: Eighty six patients with colorectal or anal cancer, mean age 57 +/- 13 yrs, were involved in a phase 1/11 multicentric, open clinical trial to assess the ability of Radioimmunoscintigraphy (RIS) with 99mTc- mAb ior c5 to detect those tumors. Seventy-four patients received 1 mg of c5 labeled with 1480-1850 MBq to determinate diagnosis efficacy and safety of murine mAb by intravenously (i.v.) bolus injection (group 1). In order to evaluate pharmacokinetic, bio distribution and dosimetry of this radiolabel molecule, 12 patients received 3 mg of labeled ior c5. Planar anterior and posterior images of the lesion sites and suspected metastases were acquired at 2, 4 and 18-24 hours after injection using a matrix size 128 x128 and 500 Kcounts per view. SPECT were scanned at 5 hr post-injection, using a 360' circular orbit with 64 images. HAMA response was measured in serum at 2, 4, 8 and 12 week post-administration. RESULTS: Labeling efficiency was (97.8 - 0.6) %. No adverse reactions or side effects were observed. Overall sensitivity, specificity, accuracy, positive and negative predictive values of the immunoscintigraphy were 95.80%, 100%, 96.51%, 100.0% and 82.35%, respectively. Unknown metastases were detected in 37 of 86 cases (43.02%). No HAMA response was found. CONCLUSIONS: Immunoscintigraphy with 99mTc-labeled mAb ior c5 could be a useful procedure for the diagnosis and follow-up of the patients with colorectal tumors, its metastasis and recurrences.
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Anticorpos Monoclonais , Neoplasias do Ânus/diagnóstico por imagem , Carcinoma/diagnóstico por imagem , Neoplasias Colorretais/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Neoplasias do Ânus/patologia , Carcinoma/patologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , CintilografiaRESUMO
AIM: To evaluate the biodistribution, internal radiation dosimetry and toxicity of the humanized MAb h-R3 labelled with Tc in humans. METHODS: Twenty-five patients with suspected epithelial-derived tumours were included in this study and divided into two groups: group I consisted of 10 patients who received 3 mg/1110 MBq (3 mg/30 mCi); and group II consisted of 15 patients who received 6 mg/2220 MBq (6 mg/60 mCi). Single photon emission computed tomography (SPECT) and planar images, and multiple blood and urine samples were collected up to 24 h after injection. Haematological parameters and adverse effects were classified according to the WHO criteria. Biodistribution, human anti-mouse antibody (HAMA) response and absorbed doses were estimated and reported. RESULTS: Liver, spleen, kidneys and heart were identified as source organs. Their higher uptakes were 53.3+/-6.4%ID, 2.0+/-1.4%ID, 9.8+/-4.3%ID and 2.8+/-0.9%ID, respectively. The urinary bladder and large intestine also had a significant uptake. The mean urinary excretion was around 22%ID. The liver received the highest absorbed doses followed by the kidneys and the urinary bladder wall. There were no haematological or biochemical abnormalities with clinical significance related to the product. No patient developed HAMA response. Preliminary analysis of clinical results showed a sensitivity of 76.5% and a specificity of 100%. CONCLUSIONS: The results of this study suggest that Tc-h-R3 could be used in patients in a safe and effective way, for the diagnosis of epithelial-derived tumours at the two evaluated dose levels.
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Anticorpos Monoclonais/química , Receptores ErbB/química , Neoplasias Epiteliais e Glandulares/terapia , Radioimunodetecção/métodos , Radioimunoterapia/métodos , Tecnécio/farmacologia , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Autoanticorpos/química , Receptores ErbB/imunologia , Feminino , Humanos , Imunoconjugados/química , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Compostos de Organotecnécio , Radiometria , Compostos Radiofarmacêuticos/farmacologia , Sensibilidade e Especificidade , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Contagem Corporal TotalRESUMO
h-R3 is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody (MAb). This receptor is over-expressed in the majority of tumors of epithelial origin, including glioblastomas. 188Rhenium (188Re) constitutes an ideal radionuclide for imagining and radioimmunotherapy, and its toxicity is known, nevertheless, it is unknown if 188Os, as 188Re's daughter, has any local or systemic toxicity effect when it is administered intracerebrally for treating intracranial tumors. For this reason we decided to assess the toxicity of stable 188Os once the complete decay of 188Re has occurred, by administering intracerebrally to rats the h-R3 labeled with 188Os. Forty rats (20 each sex) were distributed randomly into four experimental groups (ten per group): control group received 5microL of glucoheptonate solution vehicle; two other groups were treated with unlabeled or labeled h-R3 with 188Os. The remaining group served as a non-treated control group. A single 5 microL dose (2.5 microL into each lateral ventricle) of neutral solution containing 50 microg of h-R3 labeled initially with 13.25 microCi of 188Re was stereotactically administered into lateral ventricles 8 days after the conjugation with the radionuclide was done. Each animal was observed daily for detection of toxicity signs. Body weights were recorded on days 0, 7 and 14. Blood samples for analysis of hematological and clinical chemistry parameters were taken on days 0 and 14. Necropsy and histopathological studies were carried out at the end of the study. All animals gained weight by day 14. There were no changes in hematological and clinical chemistry, but minimal histopathological changes were observed at the application sites. This study shows that single doses of 188Os-h-R3 is tolerable and causes minimal local and no systemic toxicity effects in rats.
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Anticorpos Monoclonais/toxicidade , Encéfalo/efeitos dos fármacos , Osmio/toxicidade , Radioisótopos/administração & dosagem , Radioisótopos/toxicidade , Animais , Anticorpos Monoclonais/administração & dosagem , Encéfalo/patologia , Receptores ErbB/imunologia , Feminino , Injeções Intraventriculares , Masculino , Osmio/administração & dosagem , Ratos , Ratos Sprague-DawleyRESUMO
PURPOSE: To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built. PATIENTS AND METHODS: Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response. RESULTS: The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity. CONCLUSION: h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms.