RESUMO
Prostate-specific membrane antigen (PSMA) is a membrane-bound glutamate carboxypeptidase that is highly expressed in nearly all prostate cancers with the highest expression in metastatic castration-resistant prostate cancer (mCRPC). The prevalence of increased surface expression and constitutive internalization of PSMA make it an attractive target for an antibody-drug conjugate (ADC) approach to treating patients with mCRPC. MEDI3726 (previously known as ADCT-401) is an ADC consisting of an engineered version of the anti-PSMA antibody J591 site specifically conjugated to the pyrrolobenzodiazepine (PBD) dimer tesirine. MEDI3726 specifically binds the extracellular domain of PSMA and, once internalized, releases the PBD dimer to crosslink DNA and trigger cell death. In vitro, MEDI3726 demonstrated potent and specific cytotoxicity in a panel of PSMA-positive prostate cancer cell lines, consistent with internalization and DNA interstrand crosslinking. In vivo, MEDI3726 showed robust antitumor activity against the LNCaP and the castration-resistant CWR22Rv1 prostate cancer cell line xenografts. MEDI3726 also demonstrated durable antitumor activity in the PSMA-positive human prostate cancer patient-derived xenograft (PDX) LuCaP models. This activity correlated with increased phosphorylated Histone H2AX in tumor xenografts treated with MEDI3726. MEDI3726 is being evaluated in a phase I clinical trial as a treatment for patients with metastatic castrate-resistant prostate cancer (NCT02991911). Mol Cancer Ther; 17(10); 2176-86. ©2018 AACR.
Assuntos
Antineoplásicos Imunológicos/farmacologia , Biomarcadores Tumorais/antagonistas & inibidores , Glutamato Carboxipeptidase II/antagonistas & inibidores , Imunoconjugados/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/imunologia , Animais , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Linhagem Celular Tumoral , Reações Cruzadas/imunologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Expressão Gênica , Glutamato Carboxipeptidase II/genética , Glutamato Carboxipeptidase II/metabolismo , Humanos , Imuno-Histoquímica , Macaca fascicularis , Masculino , Camundongos , Neoplasias da Próstata/patologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Toxicokinetic analysis is an essential part of nonclinical drug development. Advances in bioanalytical techniques have opened up the potential to use smaller sample volumes (microsamples) to assess drug exposure in blood, plasma and/or serum. Microsampling can increase the amount of nonclinical safety information available, improve its validity by linking toxic effects to drug exposure in individual animals and represents the most significant opportunity to reduce animal use in toxicology studies in the short term. In May 2013, a workshop was held with 80 delegates from 33 companies with the aim of sharing information and knowledge on microsampling technologies. This article covers the discussions at the workshop, current practice in the industry, regulatory experiences and the future direction of microsampling across drug development.