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1.
Cancer Lett ; 587: 216713, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38364961

RESUMO

Human leukocyte antigen (HLA) class I defects are associated with cancer progression. However, their prognostic significance is controversial and may be modulated by immune checkpoints. Here, we investigated whether the checkpoint B7-H3 modulates the relationship between HLA class I and pancreatic ductal adenocarcinoma (PDAC) prognosis. PDAC tumors were analyzed for the expression of B7-H3, HLA class I, HLA class II molecules, and for the presence of tumor-infiltrating immune cells. We observed defective HLA class I and HLA class II expressions in 75% and 59% of PDAC samples, respectively. HLA class I and B7-H3 expression were positively related at mRNA and protein level, potentially because of shared regulation by RELA, a sub-unit of NF-kB. High B7-H3 expression and low CD8+ T cell density were indicators of poor survival, while HLA class I was not. Defective HLA class I expression was associated with unfavorable survival only in patients with low B7-H3 expression. Favorable survival was observed only when HLA class I expression was high and B7-H3 expression low. Our results provide the rationale for targeting B7-H3 in patients with PDAC tumors displaying high HLA class I levels.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Antígenos B7/genética , Antígenos B7/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Carcinoma Ductal Pancreático/patologia , Progressão da Doença , Antígenos de Histocompatibilidade Classe I , Linfócitos do Interstício Tumoral , Neoplasias Pancreáticas/metabolismo , Prognóstico
2.
Nat Med ; 29(11): 2814-2824, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37857711

RESUMO

Tebotelimab, a bispecific PD-1×LAG-3 DART molecule that blocks both PD-1 and LAG-3, was investigated for clinical safety and activity in a phase 1 dose-escalation and cohort-expansion clinical trial in patients with solid tumors or hematologic malignancies and disease progression on previous treatment. Primary endpoints were safety and maximum tolerated dose of tebotelimab when administered as a single agent (n = 269) or in combination with the anti-HER2 antibody margetuximab (n = 84). Secondary endpoints included anti-tumor activity. In patients with advanced cancer treated with tebotelimab monotherapy, 68% (184/269) experienced treatment-related adverse events (TRAEs; 22% were grade ≥3). No maximum tolerated dose was defined; the recommended phase 2 dose (RP2D) was 600 mg once every 2 weeks. There were tumor decreases in 34% (59/172) of response-evaluable patients in the dose-escalation cohorts, with objective responses in multiple solid tumor types, including PD-1-refractory disease, and in LAG-3+ non-Hodgkin lymphomas, including CAR-T refractory disease. To enhance potential anti-tumor responses, we tested margetuximab plus tebotelimab. In patients with HER2+ tumors treated with tebotelimab plus margetuximab, 74% (62/84) had TRAEs (17% were grade ≥3). The RP2D was 600 mg once every 3 weeks. The confirmed objective response rate in these patients was 19% (14/72), including responses in patients typically not responsive to anti-HER2/anti-PD-1 combination therapy. ClinicalTrials.gov identifier: NCT03219268 .


Assuntos
Neoplasias Hematológicas , Imunoconjugados , Neoplasias , Humanos , Receptor de Morte Celular Programada 1/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias/patologia , Neoplasias Hematológicas/tratamento farmacológico
3.
Nat Med ; 29(4): 888-897, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37012549

RESUMO

B7 homolog 3 (B7-H3; CD276), a tumor-associated antigen and possible immune checkpoint, is highly expressed in prostate cancer (PCa) and is associated with early recurrence and metastasis. Enoblituzumab is a humanized, Fc-engineered, B7-H3-targeting antibody that mediates antibody-dependent cellular cytotoxicity. In this phase 2, biomarker-rich neoadjuvant trial, 32 biological males with operable intermediate to high-risk localized PCa were enrolled to evaluate the safety, anti-tumor activity and immunogenicity of enoblituzumab when given before prostatectomy. The coprimary outcomes were safety and undetectable prostate-specific antigen (PSA) level (PSA0) 1 year postprostatectomy, and the aim was to obtain an estimate of PSA0 with reasonable precision. The primary safety endpoint was met with no notable unexpected surgical or medical complications, or surgical delay. Overall, 12% of patients experienced grade 3 adverse events and no grade 4 events occurred. The coprimary endpoint of the PSA0 rate 1 year postprostatectomy was 66% (95% confidence interval 47-81%). The use of B7-H3-targeted immunotherapy in PCa is feasible and generally safe and preliminary data suggest potential clinical activity. The present study validates B7-H3 as a rational target for therapy development in PCa with larger studies planned. The ClinicalTrials.gov identifier is NCT02923180.


Assuntos
Antineoplásicos , Neoplasias da Próstata , Masculino , Humanos , Antígeno Prostático Específico/uso terapêutico , Terapia Neoadjuvante , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Antígenos B7
4.
Oncology (Williston Park) ; 37(4): 176-183, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37104758

RESUMO

PURPOSE: To assess the ability of circulating tumor DNA (ctDNA)-based testing to identify patients with HER2 (encoded by ERBB2)-positive gastric/gastroesophageal adenocarcinoma (GEA) who progressed on or after trastuzumab-containing treatments were treated with combination therapy of anti-HER2 and anti-PD-1 agents. METHODS: ctDNA analysis was performed retrospectively using plasma samples collected at study entry from 86 patients participating in the phase 1/2 CP-MGAH22-05 study (NCT02689284). RESULTS: Objective response rate (ORR) was significantly higher in evaluable ERBB2 amplification-positive vs - negative patients based on ctDNA analysis at study entry (37% vs 6%, respectively; P = .00094). ORR was 23% across all patients who were evaluable for response. ERBB2 amplification was detected at study entry in 57% of patients (all HER2 positive at diagnosis), and detection was higher (88%) when HER2 status was determined by immunohistochemistry fewer than 6 months before study entry. ctDNA was detected in 98% (84/86) of patients tested at study entry. Codetected ERBB2-activating mutations were not associated with response. CONCLUSIONS: Current ERBB2 status may be more effective than archival status at predicting clinical benefit from margetuximab plus pembrolizumab therapy. ctDNA testing for ERBB2 status prior to treatment will spare patients from repeat tissue biopsies, which may be reserved for reflex testing when ctDNA is not detected.


Assuntos
Adenocarcinoma , DNA Tumoral Circulante , Neoplasias Gástricas , Humanos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Receptor ErbB-2/genética , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Trastuzumab/uso terapêutico
5.
Mol Cancer Ther ; 21(7): 1047-1059, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35511740

RESUMO

ADAM metallopeptidase domain 9 (ADAM9) is a member of the ADAM family of multifunctional, multidomain type 1 transmembrane proteins. ADAM9 is overexpressed in many cancers, including non-small cell lung, pancreatic, gastric, breast, ovarian, and colorectal cancer, but exhibits limited expression in normal tissues. A target-unbiased discovery platform based on intact tumor and progenitor cell immunizations, followed by an IHC screen, led to the identification of anti-ADAM9 antibodies with selective tumor-versus-normal tissue binding. Subsequent analysis revealed anti-ADAM9 antibodies were efficiently internalized and processed by tumor cells making ADAM9 an attractive target for antibody-drug conjugate (ADC) development. Here, we describe the preclinical evaluation of IMGC936, a novel ADC targeted against ADAM9. IMGC936 is comprised of a high-affinity humanized antibody site-specifically conjugated to DM21-C, a next-generation linker-payload that combines a maytansinoid microtubule-disrupting payload with a stable tripeptide linker, at a drug antibody ratio of approximately 2.0. In addition, the YTE mutation (M252Y/S254T/T256E) was introduced into the CH2 domain of the antibody Fc to maximize in vivo plasma half-life and exposure. IMGC936 exhibited cytotoxicity toward ADAM9-positive human tumor cell lines, as well as bystander killing, potent antitumor activity in human cell line-derived xenograft and patient-derived xenograft tumor models, and an acceptable safety profile in cynomolgus monkeys with favorable pharmacokinetic properties. Our preclinical data provide a strong scientific rationale for the further development of IMGC936 as a therapeutic candidate for the treatment of ADAM9-positive cancers. A first-in-human study of IMGC936 in patients with advanced solid tumors has been initiated (NCT04622774).


Assuntos
Imunoconjugados , Proteínas ADAM , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Imunoconjugados/química , Proteínas de Membrana/genética , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Immunother Cancer ; 10(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35414591

RESUMO

BACKGROUND: Availability of checkpoint inhibitors has created a paradigm shift in the management of patients with solid tumors. Despite this, most patients do not respond to immunotherapy, and there is considerable interest in developing combination therapies to improve response rates and outcomes. B7-H3 (CD276) is a member of the B7 family of cell surface molecules and provides an alternative immune checkpoint molecule to therapeutically target alone or in combination with programmed cell death-1 (PD-1)-targeted therapies. Enoblituzumab, an investigational anti-B7-H3 humanized monoclonal antibody, incorporates an immunoglobulin G1 fragment crystallizable (Fc) domain that enhances Fcγ receptor-mediated antibody-dependent cellular cytotoxicity. Coordinated engagement of innate and adaptive immunity by targeting distinct members of the B7 family (B7-H3 and PD-1) is hypothesized to provide greater antitumor activity than either agent alone. METHODS: In this phase I/II study, patients received intravenous enoblituzumab (3-15 mg/kg) weekly plus intravenous pembrolizumab (2 mg/kg) every 3 weeks during dose-escalation and cohort expansion. Expansion cohorts included non-small cell lung cancer (NSCLC; checkpoint inhibitor [CPI]-naïve and post-CPI, programmed death-ligand 1 [PD-L1] <1%), head and neck squamous cell carcinoma (HNSCC; CPI-naïve), urothelial cancer (post-CPI), and melanoma (post-CPI). Disease was assessed using Response Evaluation Criteria in Solid Tumors version 1.1 after 6 weeks and every 9 weeks thereafter. Safety and pharmacokinetic data were provided for all enrolled patients; efficacy data focused on HNSCC and NSCLC cohorts. RESULTS: Overall, 133 patients were enrolled and received ≥1 dose of study treatment. The maximum tolerated dose of enoblituzumab with pembrolizumab at 2 mg/kg was not reached. Intravenous enoblituzumab (15 mg/kg) every 3 weeks plus pembrolizumab (2 mg/kg) every 3 weeks was recommended for phase II evaluation. Treatment-related adverse events occurred in 116 patients (87.2%) and were grade ≥3 in 28.6%. One treatment-related death occurred (pneumonitis). Objective responses occurred in 6 of 18 (33.3% [95% CI 13.3 to 59.0]) patients with CPI-naïve HNSCC and in 5 of 14 (35.7% [95% CI 12.8 to 64.9]) patients with CPI-naïve NSCLC. CONCLUSIONS: Checkpoint targeting with enoblituzumab and pembrolizumab demonstrated acceptable safety and antitumor activity in patients with CPI-naïve HNSCC and NSCLC. TRIAL REGISTRATION NUMBER: NCT02475213.


Assuntos
Antineoplásicos Imunológicos , Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias de Cabeça e Pescoço , Neoplasias Pulmonares , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Antígenos B7 , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Neoplasias Pulmonares/patologia , Receptor de Morte Celular Programada 1 , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico
7.
Cell Rep Med ; 1(9): 100163, 2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33377134

RESUMO

Combination immunotherapy with antibodies directed against PD-1 and CTLA-4 shows improved clinical benefit across cancer indications compared to single agents, albeit with increased toxicity. Leveraging the observation that PD-1 and CTLA-4 are co-expressed by tumor-infiltrating lymphocytes, an investigational PD-1 x CTLA-4 bispecific DART molecule, MGD019, is engineered to maximize checkpoint blockade in the tumor microenvironment via enhanced CTLA-4 blockade in a PD-1-binding-dependent manner. In vitro, MGD019 mediates the combinatorial blockade of PD-1 and CTLA-4, confirming dual inhibition via a single molecule. MGD019 is well tolerated in non-human primates, with evidence of both PD-1 and CTLA-4 blockade, including increases in Ki67+CD8 and ICOS+CD4 T cells, respectively. In the ongoing MGD019 first-in-human study enrolling patients with advanced solid tumors (NCT03761017), an analysis undertaken following the dose escalation phase revealed acceptable safety, pharmacodynamic evidence of combinatorial blockade, and objective responses in multiple tumor types typically unresponsive to checkpoint inhibitor therapy.


Assuntos
Anticorpos/uso terapêutico , Antígeno CTLA-4/imunologia , Imunoterapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Antígeno CTLA-4/efeitos dos fármacos , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Receptor de Morte Celular Programada 1/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
8.
Mol Cancer Ther ; 19(11): 2235-2244, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32967924

RESUMO

B7-H3, also referred to as CD276, is a member of the B7 family of immune regulatory proteins. B7-H3 is overexpressed on many solid cancers, including prostate cancer, renal cell carcinoma, melanoma, squamous cell carcinoma of the head and neck, non-small cell lung cancer, and breast cancer. Overexpression of B7-H3 is associated with disease severity, risk of recurrence and reduced survival. In this article, we report the preclinical development of MGC018, an antibody-drug conjugate targeted against B7-H3. MGC018 is comprised of the cleavable linker-duocarmycin payload, valine-citrulline-seco duocarmycin hydroxybenzamide azaindole (vc-seco-DUBA), conjugated to an anti-B7-H3 humanized IgG1/kappa mAb through reduced interchain disulfides, with an average drug-to-antibody ratio of approximately 2.7. MGC018 exhibited cytotoxicity toward B7-H3-positive human tumor cell lines, and exhibited bystander killing of target-negative tumor cells when cocultured with B7-H3-positive tumor cells. MGC018 displayed potent antitumor activity in preclinical tumor models of breast, ovarian, and lung cancer, as well as melanoma. In addition, antitumor activity was observed toward patient-derived xenograft models of breast, prostate, and head and neck cancer displaying heterogeneous expression of B7-H3. Importantly, MGC018 exhibited a favorable pharmacokinetic and safety profile in cynomolgus monkeys following repeat-dose administration. The antitumor activity observed preclinically with MGC018, together with the positive safety profile, provides evidence of a potentially favorable therapeutic index and supports the continued development of MGC018 for the treatment of solid cancers. GRAPHICAL ABSTRACT: http://mct.aacrjournals.org/content/molcanther/19/11/2235/F1.large.jpg.


Assuntos
Antígenos B7/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , Inibidores de Checkpoint Imunológico/farmacologia , Imunoconjugados/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antígenos B7/genética , Antígenos B7/metabolismo , Efeito Espectador , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos , Técnicas de Silenciamento de Genes , Humanos , Inibidores de Checkpoint Imunológico/química , Inibidores de Checkpoint Imunológico/isolamento & purificação , Imunoconjugados/química , Imunoconjugados/isolamento & purificação , Camundongos , Neoplasias/metabolismo , Neoplasias/patologia , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Immunotoxicol ; 17(1): 67-85, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32100588

RESUMO

Currently, there is a multitude of CD3 bispecifics with different molecular designs and binding properties in preclinical and clinical development for the treatment of liquid or solid tumors. The key safety concerns with CD3 bispecifics are excessive release of cytokines, which may translate to potentially life-threating cytokine release syndrome (CRS), target organ toxicity due to redirection of T-cells to normal tissues expressing the tumor-associated antigen (TAA) (off-tumor/on-target cytotoxicity), and, in some instances, neurotoxicity. Another key challenge is to arrive at a safe clinical starting dose and an efficient escalating strategy that allows patients in early dose cohorts the potential for clinical benefit in Phase 1 trials. To expand the therapeutic index and bring more treatment options to patients, there are intense efforts to overcome these challenges through improvements in molecular design, preclinical safety assessment strategies, and clinical management practices. A recent workshop at the U.S. Food and Drug Administration (FDA) with industry, academic, and regulatory agency representation was held to discuss the challenges and explore where such improvements to the development of CD3 bispecifics can be implemented. Here, the content of the presentations and the discussion that occurred during this workshop are summarized.


Assuntos
Anticorpos Biespecíficos/toxicidade , Antígenos de Neoplasias/metabolismo , Antineoplásicos/toxicidade , Complexo CD3/antagonistas & inibidores , Síndrome da Liberação de Citocina/prevenção & controle , Animais , Anticorpos Biespecíficos/administração & dosagem , Antígenos de Neoplasias/imunologia , Antineoplásicos/administração & dosagem , Complexo CD3/imunologia , Complexo CD3/metabolismo , Consenso , Conferências de Consenso como Assunto , Síndrome da Liberação de Citocina/induzido quimicamente , Síndrome da Liberação de Citocina/imunologia , Citocinas/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais/normas , Europa (Continente) , Humanos , Japão , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T/antagonistas & inibidores , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Pesquisa Translacional Biomédica/normas , Estados Unidos , United States Food and Drug Administration
10.
J Diabetes Complications ; 33(9): 603-609, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31235433

RESUMO

AIM: To assess the role of periodontal disease (PD) as a predictor of coronary artery disease (CAD) and mortality in a prospective type 1 diabetes (T1D) cohort and to evaluate the role of smoking in this relationship. METHODS: Data were based on 320 participants of the Pittsburgh Epidemiology of Diabetes Complications study of T1D who, during 1992-94, received a partial mouth periodontal exam, and who were followed for up to 19 years to ascertain complication incidence. PD was defined as clinical attachment loss of ≥4 mm for at least 10% of the examined sites. Predictors of all-cause mortality; Hard CAD (CAD death, myocardial infarction or revascularization), and Total CAD (Hard CAD, angina, ischemic ECG) were assessed using Cox models. RESULTS: During 19 years of follow-up, 33.7% (97/288) developed CAD, 27.3% (83/304) developed Hard CAD, and 16.9% (54/320) died. Among current smokers, 46.4% (26/56) developed CAD, 42.7% (24/56) developed Hard CAD and 29.5% (18/61) died. PD was not associated with all-cause mortality, although it was a significant predictor of both CAD (HR = 1.12, CI = 1.01-1.23) and Hard CAD (HR = 1.30, CI = 1.11-1.51). As smoking modified the PD-CAD and PD-Hard CAD associations, analyses were stratified by smoking status. PD was associated with an increased risk of CAD (HR = 1.25, CI = 1.03-1.50) and Hard CAD (HR = 1.85, CI = 1.17-2.93) only among smokers. CONCLUSION: PD was a significant predictor of CAD and Hard CAD among current smokers with T1D.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Doenças Periodontais/epidemiologia , Fumar/epidemiologia , Adulto , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos
11.
MedEdPORTAL ; 15: 10855, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31934617

RESUMO

Introduction: The opioid epidemic has awakened educators to the insufficiency of training in the areas of pain management and substance use disorders within the curricula of health sciences schools. The University of Pittsburgh Center of Excellence in Pain Education created an online educational module focusing on factors contributing to the opioid epidemic and the role of robust interprofessional communication in avoiding common practitioner errors. Methods: The 1-hour module created by an interprofessional team comprised a pretest, video presentation featuring case vignettes, posttest, and learner satisfaction survey. The content of the module focused on four core concepts: (1) managing acute perioperative pain, (2) maximizing opioid safety, and (3) identifying and (4) managing suspected opioid abuse and diversion. Results: Data were obtained from 250 dental, pharmacy, and nursing students from the University of Pittsburgh who completed the module as part of their respective profession-specific curricula. Results collapsed across the three school-specific implementations indicated an average increase in knowledge test scores from pre- to posttest (Z = -8.82, p < .001). In addition, the learner satisfaction data revealed an overall positive response to the module, with students commenting that they enjoyed the module and felt it provided them with a valuable learning experience. Discussion: Learner outcomes and feedback suggest that our interprofessional team was successful in creating an effective learning module applicable to several health care professions, namely, pharmacy, dentistry, and nursing. Future studies might address the application of the knowledge gained to actual patient care.


Assuntos
Analgésicos Opioides/uso terapêutico , Dor Facial/tratamento farmacológico , Dente Serotino/cirurgia , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Manejo da Dor/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Extração Dentária/efeitos adversos , Instrução por Computador , Avaliação Educacional , Pesquisas sobre Atenção à Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estudantes de Odontologia , Estudantes de Enfermagem , Estudantes de Farmácia
12.
Mol Cancer Ther ; 17(8): 1761-1772, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29866746

RESUMO

We have developed MGD007 (anti-glycoprotein A33 x anti-CD3), a DART protein designed to redirect T cells to target gpA33 expressing colon cancer. The gpA33 target was selected on the basis of an antibody-based screen to identify cancer antigens universally expressed in both primary and metastatic colorectal cancer specimens, including putative cancer stem cell populations. MGD007 displays the anticipated-bispecific binding properties and mediates potent lysis of gpA33-positive cancer cell lines, including models of colorectal cancer stem cells, through recruitment of T cells. Xenograft studies showed tumor growth inhibition at doses as low as 4 µg/kg. Both CD8 and CD4 T cells mediated lysis of gpA33-expressing tumor cells, with activity accompanied by increases in granzyme and perforin. Notably, suppressive T-cell populations could also be leveraged to mediate lysis of gpA33-expressing tumor cells. Concomitant with CTL activity, both T-cell activation and expansion are observed in a gpA33-dependent manner. No cytokine activation was observed with human PBMC alone, consistent with the absence of gpA33 expression on peripheral blood cell populations. Following prolonged exposure to MGD007 and gpA33 positive tumor cells, T cells express PD-1 and LAG-3 and acquire a memory phenotype but retain ability to support potent cell killing. In cynomolgus monkeys, 4 weekly doses of 100 µg/kg were well tolerated, with prolonged PK consistent with that of an Fc-containing molecule. Taken together, MGD007 displays potent activity against colorectal cancer cells consistent with a mechanism of action endowed in its design and support further investigation of MGD007 as a potential novel therapeutic treatment for colorectal cancer. Mol Cancer Ther; 17(8); 1761-72. ©2018 AACR.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Imunoterapia/métodos , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Feminino , Haplorrinos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Metástase Neoplásica
13.
Oncoimmunology ; 7(4): e1341032, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29632712

RESUMO

Many patients with B-cell malignancies can be successfully treated, although tumor eradication is rarely achieved. T-cell-directed killing of tumor cells using engineered T-cells or bispecific antibodies is a promising approach for the treatment of hematologic malignancies. We investigated the efficacy of CD19xCD3 DART bispecific antibody in a broad panel of human primary B-cell malignancies. The CD19xCD3 DART identified 2 distinct subsets of patients, in which the neoplastic lymphocytes were eliminated with rapid or slow kinetics. Delayed responses were always overcome by a prolonged or repeated DART exposure. Both CD4 and CD8 effector cytotoxic cells were generated, and DART-mediated killing of CD4+ cells into cytotoxic effectors required the presence of CD8+ cells. Serial exposures to DART led to the exponential expansion of CD4 + and CD8 + cells and to the sequential ablation of neoplastic cells in absence of a PD-L1-mediated exhaustion. Lastly, patient-derived neoplastic B-cells (B-Acute Lymphoblast Leukemia and Diffuse Large B Cell Lymphoma) could be proficiently eradicated in a xenograft mouse model by DART-armed cytokine induced killer (CIK) cells. Collectively, patient tailored DART exposures can result in the effective elimination of CD19 positive leukemia and B-cell lymphoma and the association of bispecific antibodies with unmatched CIK cells represents an effective modality for the treatment of CD19 positive leukemia/lymphoma.

14.
Clin Cancer Res ; 23(6): 1506-1518, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27663593

RESUMO

Purpose: CD19, a B-cell lineage-specific marker, is highly represented in B-cell malignancies and an attractive target for therapeutic interventions. MGD011 is a CD19 x CD3 DART bispecific protein designed to redirect T lymphocytes to eliminate CD19-expressing cells. MGD011 has been engineered with a modified human Fc domain for improved pharmacokinetic (PK) properties and designed to cross-react with the corresponding antigens in cynomolgus monkeys. Here, we report on the preclinical activity, safety and PK properties of MGD011.Experimental Design: The activity of MGD011 was evaluated in several in vitro and in vivo models. PK, safety and pharmacodynamic activity was also assessed in dose-escalation and repeat-dose studies of MGD011 administered once weekly in cynomolgus monkeys.Results: MGD011 mediated killing of human B-cell lymphoma lines by human or cynomolgus monkey PBMCs as well as autologous B-cell depletion in PBMCs from both species. MGD011-mediated killing was accompanied by target-dependent T-cell activation and expansion, cytokine release and upregulation of perforin and granzyme B. MGD011 demonstrated antitumor activity against localized and disseminated lymphoma xenografts reconstituted with human PBMCs. In cynomolgus monkeys, MGD011 displayed a terminal half-life of 6.7 days; once weekly intravenous infusion of MGD011 at doses up to 100 µg/kg, the highest dose tested, was well tolerated and resulted in dose-dependent, durable decreases in circulating B cells accompanied by profound reductions of B lymphocytes in lymphoid organs.Conclusions: The preclinical activity, safety and PK profile support clinical investigation of MGD011 as a therapeutic candidate for the treatment of B-cell malignancies. Clin Cancer Res; 23(6); 1506-18. ©2016 AACR.


Assuntos
Anticorpos Biespecíficos/administração & dosagem , Antígenos CD19/imunologia , Linfoma de Células B/tratamento farmacológico , Linfócitos T/imunologia , Animais , Anticorpos Biespecíficos/imunologia , Antígenos CD19/uso terapêutico , Humanos , Linfoma de Células B/imunologia , Linfoma de Células B/patologia , Macaca fascicularis , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Blood ; 127(1): 122-31, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26531164

RESUMO

T-cell-directed killing of tumor cells using bispecific antibodies is a promising approach for the treatment of hematologic malignancies. Here we describe our preclinical work with a dual-affinity retargeting (DART) molecule generated from antibodies to CD3 and CD123, designed to redirect T cells against acute myeloid leukemia blasts. The CD3×CD123 DART (also referred to as MGD006/S80880) consists of 2 independent polypeptides, each composed of the VH of 1 antibody in tandem with the VL of the other antibody. The target antigen CD123 (interleukin 3RA) is highly and differentially expressed in acute myeloid leukemia (AML) blasts compared with normal hematopoietic stem and progenitor cells. In this study we demonstrate that the CD3×CD123 DART binds to both human CD3 and CD123 to mediate target-effector cell association, T-cell activation, proliferation, and receptor diversification. The CD3×CD123 DART also induces a dose-dependent killing of AML cell lines and primary AML blasts in vitro and in vivo. These results provide the basis for testing the CD3×CD123 DART in the treatment of patients with CD123(+) AML.


Assuntos
Anticorpos Biespecíficos/imunologia , Apoptose , Complexo CD3/imunologia , Subunidade alfa de Receptor de Interleucina-3/imunologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/terapia , Linfócitos T/imunologia , Animais , Complexo CD3/metabolismo , Proliferação de Células , Citometria de Fluxo , Genes Codificadores da Cadeia alfa de Receptores de Linfócitos T/genética , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Técnicas Imunoenzimáticas , Subunidade alfa de Receptor de Interleucina-3/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Antibodies (Basel) ; 5(1)2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-31557987

RESUMO

Bispecific antibodies offer a promising approach for the treatment of cancer but can be challenging to engineer and manufacture. Here we report the development of PF-06671008, an extended-half-life dual-affinity re-targeting (DART®) bispecific molecule against P-cadherin and CD3 that demonstrates antibody-like properties. Using phage display, we identified anti-P-cadherin single chain Fv (scFv) that were subsequently affinity-optimized to picomolar affinity using stringent phage selection strategies, resulting in low picomolar potency in cytotoxic T lymphocyte (CTL) killing assays in the DART format. The crystal structure of this disulfide-constrained diabody shows that it forms a novel compact structure with the two antigen binding sites separated from each other by approximately 30 Å and facing approximately 90° apart. We show here that introduction of the human Fc domain in PF-06671008 has produced a molecule with an extended half-life (-4.4 days in human FcRn knock-in mice), high stability (Tm1 > 68 °C), high expression (>1 g/L), and robust purification properties (highly pure heterodimer), all with minimal impact on potency. Finally, we demonstrate in vivo anti-tumor efficacy in a human colorectal/human peripheral blood mononuclear cell (PBMC) co-mix xenograft mouse model. These results suggest PF-06671008 is a promising new bispecific for the treatment of patients with solid tumors expressing P-cadherin.

17.
Curr Med Res Opin ; 31(12): 2185-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26471741

RESUMO

The results of numerous double-blind, placebo-controlled clinical trials consistently demonstrate that nonsteroidal antiinflammatory drugs should be the first line agents in treating postsurgical dental pain. Additive and potential opioid-sparing effects have also been reported in oral surgery pain by combining an optimal dose of an NSAID with acetaminophen 500 mg. While opioid combination drugs are indicated in some dental postsurgical patients, clinicians can no longer ignore the scourge of prescription opioid abuse in the United States. Other potential opioid sparing strategies include the use of locally delivered antimicrobial/antiinflammatory agents such as Bexident Post or extended duration local anesthetic agents such as liposomal bupivacaine placed directly in or in the vicinity of the extraction socket.


Assuntos
Cicatriz/prevenção & controle , Inflamação/tratamento farmacológico , Dor Pós-Operatória/tratamento farmacológico , Extração Dentária/métodos , Feminino , Humanos , Masculino
18.
Clin Proteomics ; 12(1): 18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26279647

RESUMO

BACKGROUND: Support for early detection of lung cancer has emerged from the National Lung Screening Trial (NLST), in which low-dose computed tomography (LDCT) screening reduced lung cancer mortality by 20 % relative to chest x-ray. The US Preventive Services Task Force (USPSTF) recently recommended annual screening for the high-risk population, concluding that the benefits (life years gained) outweighed harms (false positive findings, abortive biopsy/surgery, radiation exposure). In making their recommendation, the USPSTF noted that the moderate net benefit of screening was dependent on the resolution of most false-positive results without invasive procedures. Circulating biomarkers may serve as a valuable adjunctive tool to imaging. RESULTS: We developed a broad-based proteomics discovery program, integrating liquid chromatography/mass spectrometry (LC/MS) analyses of freshly resected lung tumor specimens (n = 13), lung cancer cell lines (n = 17), and conditioned media collected from tumor cell lines (n = 7). To enrich for biomarkers likely to be found at elevated levels in the peripheral circulation of lung cancer patients, proteins were prioritized based on predicted subcellular localization (secreted, cell-membrane associated) and differential expression in disease samples. 179 candidate biomarkers were identified. Several markers selected for further validation showed elevated levels in serum collected from subjects with stage I NSCLC (n = 94), relative to healthy smoker controls (n = 189). An 8-marker model was developed (TFPI, MDK, OPN, MMP2, TIMP1, CEA, CYFRA 21-1, SCC) which accurately distinguished subjects with lung cancer (n = 50) from high risk smokers (n = 50) in an independent validation study (AUC = 0.775). CONCLUSIONS: Integrating biomarker discovery from multiple sample types (fresh tissue, cell lines and conditioned medium) has resulted in a diverse repertoire of candidate biomarkers. This unique collection of biomarkers may have clinical utility in lung cancer detection and diagnoses.

19.
Arch Environ Contam Toxicol ; 69(4): 557-65, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26115694

RESUMO

Environmental pollutants, such as crude oil and other petroleum-based fuels, inhibit and limit an organism's ability to perceive a chemical stimulus. Despite the increased use of alternative fuels, such as biodiesel, there have been few studies investigating the impact of these chemicals on the behavior of aquatic organisms. The purpose of this study was to compare the sublethal effects of biodiesel and crude oil exposure on chemically mediated behaviors in a freshwater keystone species. Crayfish (Orconectes rusticus) were tested on their ability to respond appropriately to a positive chemical stimulus within a Y-maze choice paradigm. Behavior was quantified by measuring time spent finding an odor source, duration of time spent at the odor source, percentage of crayfish that found the odor source, and percentage of crayfish that chose the correct arm of the arena. Results indicated negative impacts of both biodiesel and crude oil on the ability of crayfish to locate the food source. However, there were no significant differences between behavioral performances when crayfish were exposed to crude oil compared with biodiesel. Thus, biodiesel and crude oil have equally negative effects on the chemosensory behavior of crayfish. These findings indicate that biodiesel has the potential to have similar negative ecological impacts as other fuel source toxins.


Assuntos
Astacoidea/fisiologia , Biocombustíveis/toxicidade , Comportamento Alimentar/efeitos dos fármacos , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidade , Animais
20.
Sci Transl Med ; 7(289): 289ra82, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-26019218

RESUMO

Current therapies for acute myeloid leukemia (AML) are largely ineffective, and AML patients may benefit from targeted immunotherapy approaches. MGD006 is a bispecific CD3xCD123 dual-affinity re-targeting (DART) molecule that binds T lymphocytes and cells expressing CD123, an antigen up-regulated in several hematological malignancies including AML. MGD006 mediates blast killing in AML samples, together with concomitant activation and expansion of residual T cells. MGD006 is designed to be rapidly cleared, and therefore requires continuous delivery. In a mouse model of continuous administration, MGD006 eliminated engrafted KG-1a cells (an AML-M0 line) in human PBMC (peripheral blood mononuclear cell)-reconstituted NSG/ß2m(-/-) mice at doses as low as 0.5 µg/kg per day for ~7 days. MGD006 binds to human and cynomolgus monkey antigens with similar affinities and redirects T cells from either species to kill CD123-expressing target cells. MGD006 was well tolerated in monkeys continuously infused with 0.1 µg/kg per day escalated weekly to up to 1 µg/kg per day during a 4-week period. Depletion of circulating CD123-positive cells was observed as early as 72 hours after treatment initiation and persisted throughout the infusion period. Cytokine release, observed after the first infusion, was reduced after subsequent administrations, even when the dose was escalated. T cells from animals with prolonged in vivo exposure exhibited unperturbed target cell lysis ex vivo, indicating no exhaustion. A transient decrease in red cell mass was observed, with no neutropenia or thrombocytopenia. These studies support clinical testing of MGD006 in hematological malignancies, including AML.


Assuntos
Complexo CD3/metabolismo , Subunidade alfa de Receptor de Interleucina-3/metabolismo , Leucemia Mieloide Aguda/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD , Medula Óssea/patologia , Morte Celular , Proliferação de Células , Citocinas/metabolismo , Relação Dose-Resposta Imunológica , Feminino , Hematopoese , Humanos , Leucemia Mieloide Aguda/patologia , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Macaca fascicularis , Masculino , Camundongos , Ligação Proteica , Engenharia de Proteínas
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