RESUMO
Treatment of acute myeloid leukemia (AML) among the elderly is challenging because of intolerance of intensive therapy and therapy-resistant biology. Hypomethylating agents (HMAs) are commonly used, with suboptimal outcomes. Vadastuximab talirine is a CD33-directed antibody conjugated to pyrrolobenzodiazepine (PBD) dimers. Preclinically, HMAs followed by vadastuximab talirine produced upregulated CD33 expression, increased DNA incorporation by PBD, and enhanced cytotoxicity. A combination cohort in a phase 1 study (NCT01902329) assessed safety, tolerability, and activity of vadastuximab talirine with HMAs. Those eligible had Eastern Cooperative Oncology Group status 0 to 1 and previously untreated CD33-positive AML, and declined intensive therapy. Vadastuximab talirine was administered intravenously at 10 µg/kg on last day of HMA (azacitidine or decitabine) infusion in 4-week cycles. Among 53 patients treated, the median age was 75 years. Patients had adverse (38%) or intermediate (62%) cytogenetic risk. Median treatment duration was 19.3 weeks. No dose-limiting toxicities were reported. The majority of adverse events were a result of myelosuppression, with some causing therapy delays. Thirty- and 60-day mortality rates were 2% and 8%, respectively. The composite remission rate (complete remission [CR] and CR with incomplete blood count recovery) was 70%. Fifty-one percent of remissions were minimal residual disease-negative by flow cytometry. Similarly high remission rates were observed in patients with secondary AML, aged at least 75 years, and with adverse cytogenetic risk. Median relapse-free survival and overall survival were 7.7 and 11.3 months, respectively. Compared with historical data for HMA monotherapy, the combination of vadastuximab talirine with HMAs produced a high remission rate, but was accompanied by increased hematologic toxicity.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Leucemia Mieloide Aguda/tratamento farmacológico , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Azacitidina/administração & dosagem , Azacitidina/efeitos adversos , Azacitidina/farmacocinética , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Benzodiazepinas/farmacocinética , Decitabina/administração & dosagem , Decitabina/efeitos adversos , Decitabina/farmacocinética , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Pirróis/administração & dosagem , Pirróis/efeitos adversos , Pirróis/farmacocinética , Taxa de SobrevidaRESUMO
The kidney proximal tubule is the primary site in the nephron for excretion of waste products through a combination of active uptake and secretory processes and is also a primary target of drug-induced nephrotoxicity. Here, we describe the development and functional characterization of a 3-dimensional flow-directed human kidney proximal tubule microphysiological system. The system replicates the polarity of the proximal tubule, expresses appropriate marker proteins, exhibits biochemical and synthetic activities, as well as secretory and reabsorptive processes associated with proximal tubule function in vivo. This microphysiological system can serve as an ideal platform for ex vivo modeling of renal drug clearance and drug-induced nephrotoxicity. Additionally, this novel system can be used for preclinical screening of new chemical compounds prior to initiating human clinical trials.
Assuntos
Túbulos Renais Proximais/fisiologia , Modelos Biológicos , Eliminação Renal/fisiologia , Transporte Biológico Ativo , Técnicas de Cultura de Células , Sobrevivência Celular , Células Epiteliais/metabolismo , Humanos , Túbulos Renais Proximais/citologiaRESUMO
The antibody-drug conjugate (ADC) tisotumab vedotin (TV) received accelerated approval from the US Food and Drug Administration for treatment of adults with recurrent or metastatic cervical cancer (r/mCC) with disease progression on or after chemotherapy. A population pharmacokinetic (PK) model, developed using dosing data from four clinical TV studies, was used to estimate individual exposure and explore safety and efficacy exposure-response (ER) relationships. Because PK analysis showed no appreciable accumulation of TV and monomethyl auristatin E (MMAE) with repeated dosing, cycle 1 exposure metrics and predicted average concentrations from time zero until end of the cycle in which an event occurred (CavgLast ) were used for ER analyses. The probability of achieving objective response increased significantly as the ADC cycle 1 maximum serum concentration (Cmax ) increased. The probability of treatment-related adverse events (AEs) leading to dose modification increased significantly as ADC cycle 1 area under the concentration-time curve (AUC) increased. Number of grade 2+ ocular AEs increased significantly as ADC cycle 1 AUC, Cmax , and ADC CavgLast increased. MMAE cycle 1 AUC predicted risk of serious treatment-related AEs. The relationship between ADC exposure and efficacy end points suggests ADC treatment was associated with clinically meaningful response across the observed exposures; greater exposure was associated with increased efficacy. The relationship between ADC and MMAE exposure and safety end points suggests increased exposure was associated with increased AE risk. These results align with clinical findings showing TV 2 mg/kg (≤200 mg for patients ≥100 kg) every 3 weeks is efficacious and tolerable for patients with r/mCC.
Assuntos
Imunoconjugados , Recidiva Local de Neoplasia , Adulto , Humanos , Anticorpos Monoclonais Humanizados/efeitos adversos , Imunoconjugados/efeitos adversosRESUMO
Tisotumab vedotin is an investigational antibody-drug conjugate (ADC) for treatment of solid tumors expressing tissue factor with accelerated approval from the US Food and Drug Administration for treatment of recurrent or metastatic cervical cancer with disease progression during or after chemotherapy. This study describes development of a population pharmacokinetic (PK) model to assess the PK profile of tisotumab vedotin and microtubule-disrupting agent monomethyl auristatin E (MMAE) using data from 399 patients with solid tumors across four phase I/II trials. The ADC-MMAE model describes ADC and MMAE concentrations following intravenous administration of tisotumab vedotin. This four-compartment model comprises a two-compartment ADC model with parallel linear and Michaelis-Menten elimination, a delay compartment, and a one-compartment MMAE model. Nonspecific linear clearance of ADC was 1.42 L/day, central volume of distribution (Vc ) was 3.10 L, and median terminal half-life of ADC was 4.04 days. Apparent clearance of MMAE was 42.8 L/day, and apparent volume of distribution was 2.09 L. Terminal slope of the MMAE concentration-time curve was defined by the delay compartment rate with a half-life of 2.56 days. Patients with higher body weight and lower albumin concentration had faster ADC clearance. Male patients and those with higher body weight and lower albumin concentration had higher Vc . Body weight was the most influential covariate influencing distribution and elimination of ADC and MMAE, thus supporting weight-based dosing of tisotumab vedotin. Presence of antidrug antibodies (detected in 3.3% of patients) did not affect key PK parameters or exposures for ADC and MMAE.
Assuntos
Imunoconjugados , Neoplasias , Albuminas , Anticorpos Monoclonais Humanizados/farmacocinética , Peso Corporal , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Neoplasias/tratamento farmacológico , Oligopeptídeos/farmacocinética , Tromboplastina/uso terapêuticoRESUMO
The liver is the main site for drug and xenobiotics metabolism, including inactivation or bioactivation. In order to improve the predictability of drug safety and efficacy in clinical development, and to facilitate the evaluation of the potential human health effects from exposure to environmental contaminants, there is a critical need to accurately model human organ systems such as the liver in vitro. We are developing a microphysiological system (MPS) based on a new commercial microfluidic platform (Nortis, Inc.) that can utilize primary liver cells from multiple species (e.g., rat and human). Compared to conventional monolayer cell culture, which typically survives for 5-7days or less, primary rat or human hepatocytes in an MPS exhibited higher viability and improved hepatic functions, such as albumin production, expression of hepatocyte marker HNF4α and canaliculi structure, for up to 14days. Additionally, induction of Cytochrome P450 (CYP) 1A and 3A4 in cryopreserved human hepatocytes was observed in the MPS. The acute cytotoxicity of the potent hepatotoxic and hepatocarcinogen, aflatoxin B1, was evaluated in human hepatocytes cultured in an MPS, demonstrating the utility of this model for acute hepatotoxicity assessment. These results indicate that MPS-cultured hepatocytes provide a promising approach for evaluating chemical toxicity in vitro.
Assuntos
Técnicas de Cultura de Células , Doença Hepática Induzida por Substâncias e Drogas , Avaliação Pré-Clínica de Medicamentos/métodos , Testes de Toxicidade/métodos , Adulto , Aflatoxina B1/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Criança , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/metabolismo , Feminino , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Adulto JovemRESUMO
Glyburide is commonly prescribed for the treatment of gestational diabetes mellitus; however, fetal exposure to glyburide is not well understood and may have short- and long-term consequences for the health of the child. Glyburide can cross the placenta; fetal concentrations at term are nearly comparable to maternal levels. Whether or not glyburide is metabolized in the fetus and by what mechanisms has yet to be determined. In this study, we determined the kinetic parameters for glyburide depletion by CYP3A isoenzymes; characterized glyburide metabolism by human fetal liver tissues collected during the first or early second trimester of pregnancy; and identified the major enzyme responsible for glyburide metabolism in human fetal livers. CYP3A4 had the highest metabolic capacity towards glyburide, followed by CYP3A7 and CYP3A5 (Clint,u=37.1, 13.0, and 8.7ml/min/nmol P450, respectively). M5 was the predominant metabolite generated by CYP3A7 and human fetal liver microsomes (HFLMs) with approximately 96% relative abundance. M5 was also the dominant metabolite generated by CYP3A4, CYP3A5, and adult liver microsomes; however, M1-M4 were also present, with up to 15% relative abundance. CYP3A7 protein levels in HFLMs were highly correlated with glyburide Clint, 16α-OH DHEA formation, and 4'-OH midazolam formation. Likewise, glyburide Clint was highly correlated with 16α-OH DHEA formation. Fetal demographics as well as CYP3A5 and CYP3A7 genotype did not alter CYP3A7 protein levels or glyburide Clint. These results indicate that human fetal livers metabolize glyburide predominantly to M5 and that CYP3A7 is the major enzyme responsible for glyburide metabolism in human fetal livers.
Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Glibureto/metabolismo , Hipoglicemiantes/metabolismo , Fígado/embriologia , Sequência de Aminoácidos , Hidrocarboneto de Aril Hidroxilases/química , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP3A , Glibureto/farmacocinética , Humanos , Hipoglicemiantes/farmacocinética , Fígado/enzimologia , Fígado/metabolismo , Microssomos Hepáticos/enzimologia , Dados de Sequência Molecular , Espectrometria de Massas em TandemRESUMO
Kidney disease is a public health problem that affects more than 20 million people in the US adult population, yet little is understood about the impact of kidney disease on drug disposition. Consequently there is a critical need to be able to model the human kidney and other organ systems, to improve our understanding of drug efficacy, safety, and toxicity, especially during drug development. The kidneys in general, and the proximal tubule specifically, play a central role in the elimination of xenobiotics. With recent advances in molecular investigation, considerable information has been gathered regarding the substrate profiles of the individual transporters expressed in the proximal tubule. However, we have little knowledge of how these transporters coupled with intracellular enzymes and influenced by metabolic pathways form an efficient secretory and reabsorptive mechanism in the renal tubule. Proximal tubular secretion and reabsorption of xenobiotics is critically dependent on interactions with peritubular capillaries and the interstitium. We plan to robustly model the human kidney tubule interstitium, utilizing an ex vivo three-dimensional modular microphysiological system with human kidney-derived cells. The microphysiological system should accurately reflect human physiology, be usable to predict renal handling of xenobiotics, and should assess mechanisms of kidney injury, and the biological response to injury, from endogenous and exogenous intoxicants.