Publications by authors named "Quadt C"

The Werner syndrome RecQ helicase WRN was identified as a synthetic lethal target in cancer cells with microsatellite instability (MSI) by several genetic screens. Despite advances in treatment with immune checkpoint inhibitors, there is an unmet need in the treatment of MSI cancers. Here we report the structural, biochemical, cellular and pharmacological characterization of the clinical-stage WRN helicase inhibitor HRO761, which was identified through an innovative hit-finding and lead-optimization strategy.

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Article Synopsis
  • Hyperglycemia is a common side effect of PI3Kα inhibitors like alpelisib, and early detection is key for effective patient management.
  • This study used data from two clinical trials to build a machine learning model identifying baseline characteristics that predict the risk of developing severe hyperglycemia in patients.
  • The model successfully classified patients into high and low-risk groups, revealing that those at high risk experienced a significantly higher incidence of hyperglycemia and related treatment discontinuations.
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Background: Alpelisib in combination with cetuximab showed synergistic anti-tumour activity in head and neck squamous cell carcinoma (HNSCC) models.

Objectives: The recommended phase 2 dose (RP2D) was determined in a phase 1b dose-escalation study. Phase 2 evaluated anti-tumour activity with a randomised part in cetuximab-naïve patients and a non-randomised part in cetuximab-resistant patients.

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This phase I study aimed to determine tolerability and preliminary efficacy of single-agent alpelisib (BYL719) in Japanese patients with advanced solid malignancies. The primary objective of the study was to estimate the maximum tolerated dose (MTD) and/or recommended phase II dose (RP2D) of oral alpelisib in patients with advanced solid tumors who had progressed despite standard therapy. The expansion part included patients with PIK3CA mutation/amplification; safety, preliminary efficacy, pharmacokinetic (PK)/pharmacodynamic profile, and food effect on the PK profile of alpelisib at the MTD/RP2D were determined.

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Importance: The phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in patients with estrogen receptor-positive (ER+), endocrine therapy-resistant breast cancers.

Objective: To assess the maximum tolerated dose (MTD), safety, and activity of alpelisib, an oral, PI3Kα-specific inhibitor, plus fulvestrant in patients with ER+ advanced breast cancer (ABC).

Design, Setting, And Participants: An open-label, single-arm, phase 1b study of alpelisib plus fulvestrant was conducted at 10 centers in 5 countries.

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Purpose: BEZ235 is a dual kinase inhibitor of phosphatidylinositol 3-kinase (PI3K) and mammalian target of rapamycin, which are key components of the PI3K pathway. This was an open-label, multicenter, dose-escalation, phase I study of single-agent BEZ235 in Japanese oncology patients to determine the maximum tolerated dose (MTD) of BEZ235 based on dose-limiting toxicities (DLTs).

Methods: Dose escalation was guided by a standard 3 + 3 method and was based on DLTs observed in Cycle 1 and other safety, pharmacokinetic, and pharmacodynamic information.

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Purpose: To determine the maximum tolerated dose (MTD) of BEZ235, an oral inhibitor of class I PI3K and mTOR complexes 1 and 2.

Methods: We performed a phase I/Ib, multicenter, open-label study of oral BEZ235 administered in a continuous daily schedule. The study consisted of two parts: dose-escalation part and safety-expansion part.

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Purpose We report the first-in-human phase Ia study to our knowledge ( ClinicalTrials.gov identifier: NCT01219699) identifying the maximum tolerated dose and assessing safety and preliminary efficacy of single-agent alpelisib (BYL719), an oral phosphatidylinositol 3-kinase α (PI3Kα)-selective inhibitor. Patients and Methods In the dose-escalation phase, patients with PIK3CA-altered advanced solid tumors received once-daily or twice-daily oral alpelisib on a continuous schedule.

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The PI3K-AKT-mTOR pathway is frequently activated in cancer. PI3K inhibitors, including the pan-PI3K inhibitor buparlisib (BKM120) and the PI3Kα-selective inhibitor alpelisib (BYL719), currently in clinical development by Novartis Oncology, may therefore be effective as anticancer agents. Early clinical studies with PI3K inhibitors have demonstrated preliminary antitumor activity and acceptable safety profiles.

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Broad and deep tumour genome sequencing has shed new light on tumour heterogeneity and provided important insights into the evolution of metastases arising from different clones. There is an additional layer of complexity, in that tumour evolution may be influenced by selective pressure provided by therapy, in a similar fashion to that occurring in infectious diseases. Here we studied tumour genomic evolution in a patient (index patient) with metastatic breast cancer bearing an activating PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha, PI(3)Kα) mutation.

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Aims: The aim was to characterize the population pharmacokinetics of BYL719 in cancer patients and assess the time course of tumour response in relation to drug exposure and dosing schedule.

Methods: Plasma samples and longitudinal tumour size measurements were collected from 60 patients with advanced solid malignancies who received oral BYL719 once daily (30-450 mg) or twice daily at 120 mg or 200 mg. Non-linear mixed effect modelling was employed to develop the population pharmacokinetic and pharmacodynamic model.

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Buparlisib (BKM120) is an oral pan-phosphatidylinositol 3-kinase inhibitor, targeting all four isoforms of class I PI3K (α, β, γ and δ). This open-label Phase I dose-escalation study was conducted to determine the maximum tolerated dose of continuous daily buparlisib in Japanese patients with advanced solid tumors. Secondary objectives included safety and tolerability, pharmacokinetics, antitumor activity and pharmacodynamic marker changes.

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Activating mutations of the PIK3CA gene occur frequently in breast cancer, and inhibitors that are specific for phosphatidylinositol 3-kinase (PI3K) p110α, such as BYL719, are being investigated in clinical trials. In a search for correlates of sensitivity to p110α inhibition among PIK3CA-mutant breast cancer cell lines, we observed that sensitivity to BYL719 (as assessed by cell proliferation) was associated with full inhibition of signaling through the TORC1 pathway. Conversely, cancer cells that were resistant to BYL719 had persistently active mTORC1 signaling, although Akt phosphorylation was inhibited.

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Purpose: A phase I study was conducted with the primary objective of determining the maximum tolerated dose (MTD) of AUY922 in patients with advanced solid tumors. Secondary objectives included characterization of the safety, pharmacokinetic, and pharmacodynamic profiles.

Patients And Methods: Patients with advanced solid tumors received 1-hour i.

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Heat shock protein 90 (HSP90) is involved in protein folding and functions as a chaperone for numerous client proteins, many of which are important in non-small cell lung cancer (NSCLC) pathogenesis. We sought to define preclinical effects of the HSP90 inhibitor NVP-AUY922 and identify predictors of response. We assessed in vitro effects of NVP-AUY922 on proliferation and protein expression in NSCLC cell lines.

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HSP90 enables the activation of many client proteins of which the most clinically validated is HER2. NVP-AUY922, a potent HSP90 inhibitor, is currently in phase II clinical trials. To explore its potential clinical use in HER2-amplified breast and gastric cancers, we evaluated the effect of AUY922 alone and in combination with trastuzumab in both trastuzumab-sensitive and -resistant models.

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Unlabelled: Angiogenesis is a critical step in tumor development, in which vascular endothelial growth factor (VEGF) is a key growth aspect. Heat shock protein 90 (HSP90), a molecular chaperone, is essential for the activity of key proteins involved in VEGF transcription. Currently, no biomarkers to predict the effect of, or monitor, HSP90 inhibition therapy in individual patients exist.

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NVP-AUY922, a potent heat shock protein (HSP) 90 inhibitor, downregulates the expression of many oncogenic proteins, including the human epidermal growth factor receptor-2 (HER2). Because HER2 downregulation is a potential biomarker for early response to HSP90-targeted therapies, we used the (89)Zr-labelled HER2 antibody trastuzumab to quantify the alterations in HER2 expression after NVP-AUY922 treatment with HER2 positron emission tomography (PET) imaging. The HER2 overexpressing human SKOV-3 ovarian tumour cell line was used for in vitro experiments and as xenograft model in nude athymic mice.

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Heat shock protein 90 (HSP90) is a promising target for tumor therapy. The novel HSP90 inhibitor NVP-AUY922 has preclinical activity in multiple myeloma, however, little is known about effective combination partners to design clinical studies. Multiple myeloma cell lines, OPM-2, RPMI-8226, U-266, LP-1, MM1.

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The 90 kD heat shock protein (Hsp90) molecular chaperone sustains multiple components of oncogenic pathways and has recently emerged as a therapeutic target that is now being clinically tested in a number of malignancies. In order to address formulation issues and to deal with possible resistance mechanisms against small molecule Hsp90 inhibitors, a range of compounds based on different molecular scaffolds are now being developed. The present study preclinically tested the effects of the novel 2-aminothienopyrimidine class Hsp90 inhibitor NVP-BEP800, which is suitable for oral formulations, on multiple myeloma cells from established cell lines and on a larger cohort (n = 40) of primary myeloma samples.

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We as well as others have recently shown that Hsp90 is overexpressed in multiple myeloma (MM) and critically contributes to tumour cell survival. Pharmacologic blockade of Hsp90 has consistently been found to induce MM cell death. However, most data have been obtained with MM cell lines whereas knowledge about the molecular effects of pharmacologic Hsp90 blockade in primary tumour cells is limited.

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Introduction: Heat shock protein 90 (HSP90) is a key component of a multichaperone complex involved in the post-translational folding of a large number of client proteins, many of which play essential roles in tumorigenesis. HSP90 has emerged in recent years as a promising new target for anticancer therapies.

Methods: The concentrations of the HSP90 inhibitor NVP-AUY922 required to reduce cell numbers by 50% (GI50 values) were established in a panel of breast cancer cell lines and patient-derived human breast tumors.

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Aim Of The Study: Adecatumumab (also known as MT201) is a human recombinant IgG1 monoclonal antibody binding with low affinity to epithelial cell adhesion molecule (EpCAM). To explore safety, pharmacokinetics and pharmacodynamics of adecatumumab, a phase I trial in patients with hormone refractory prostate cancer (HRPC) was performed.

Methods: Twenty patients were treated with two adecatumumab infusions on days 0 and 14 in cohorts with doses of ten up to 262 mg/m2.

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BscCD19xCD3 is a bispecific single-chain antibody construct with exceptional cytotoxic potency in vitro and in vivo. Here, we have investigated the biological activity of bscCD19xCD3 in chimpanzee, the only animal species identified in which bscCD19xCD3 showed bispecific binding, redirected B-cell lysis and cytokine production comparable to human cells. Pharmacokinetic analysis following 2-h intravenous infusion of 0.

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The effects of salm-calcitonin on breast cancer osteolytic skeletal metastases have been studied on conventional radiographs. Radiographic criteria for positive response have been defined. It is concluded that radiographs are inadequate for assessing the effects of salm-calcitonin.

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