A Phase I Study of the Pan-Notch Inhibitor CB-103 for Patients with Advanced Adenoid Cystic Carcinoma and Other Tumors.

PURPOSE: CB-103 selectively inhibits the CSL-NICD (Notch intracellular domain) interaction leading to transcriptional downregulation of oncogenic Notch pathway activation. This dose-escalation/expansion study aimed to determine safety, pharmacokinetics, and preliminary antitumor activity. EXPERIMENTAL DESIGN: Patients ≥18 years of age with selected advanced solid tumors [namely, adenoid cystic carcinoma (ACC)] and hematologic malignancies were eligible. CB-103 was dosed orally in cycles of 28 days at escalating doses until disease progression. Notch-activating mutations were required in a dose confirmatory cohort. Endpoints included dose-limiting toxicities (DLT), safety, tumor response, pharmacokinetics, and pharmacodynamics. Exploratory analyses focused on correlates of Notch and target gene expression. RESULTS: Seventy-nine patients (64, 12 dose-escalation cohorts; 15, confirmatory cohort) enrolled with 54% receiving two or more lines of prior therapy. ACC was the dominant tumor type (40, 51%). Two DLTs were observed [elevated gamma-glutamyl transferase (GGT), visual change]; recommended phase II dose was declared as 500 mg twice daily (5 days on, 2 days off weekly). Grade 3-4 treatment-related adverse events occurred in 15 patients (19%), including elevated liver function tests (LFTs), anemia, and visual changes. Five (6%) discontinued drug for toxicity; with no drug-related deaths. There were no objective responses, but 37 (49%) had stable disease; including 23 of 40 (58%) patients with ACC. In the ACC cohort, median progression-free survival was 2.5 months [95% confidence interval (CI), 1.5-3.7] and median overall survival was 18.4 months (95% CI, 6.3-not reached). CONCLUSIONS: CB-103 had a manageable safety profile and biological activity but limited clinical antitumor activity as monotherapy in this first-in-human study. SIGNIFICANCE: CB-103 is a novel oral pan-Notch inhibitor that selectively blocks the CSL-NICD interaction leading to transcriptional downregulation of oncogenic Notch pathway activation. This first-in-human dose-escalation and -confirmation study aimed to determine the safety, pharmacokinetics, and preliminary antitumor efficacy of CB-103. We observed a favorable safety profile with good tolerability and biological activity but limited clinical single-agent antitumor activity. Some disease stabilization was observed among an aggressive NOTCH-mutant ACC type-I subgroup where prognosis is poor and therapies are critically needed. Peripheral downregulation of select Notch target gene levels was observed with escalating doses. Future studies exploring CB-103 should enrich for patients with NOTCH-mutant ACC and investigate rational combinatorial approaches in tumors where there is limited success with investigational or approved drugs.

Efficient synthesis of Empagliflozin, an inhibitor of SGLT-2, utilizing an AlCl3-promoted silane reduction of a ß-glycopyranoside.

An efficient production synthesis of the SGLT-2 inhibitor Empagliflozin (5) from acid 1 is described. The key tactical stage involves I/Mg exchange of aryl iodide 2 followed by addition to glucono lactone 3 in THF. Subsequent in situ treatment of the resulting lactol with HCl in MeOH produces ß-anomeric methyl glycopyranoside 4 which is, without isolation, directly reduced with Et3SiH mediated by AlCl3 as a Lewis acid in CH2Cl2/MeCN to afford 5 in 50% overall yield. The process was implemented for production on a metric ton scale for commercial launch.

Randomized, open-label, phase III study comparing patupilone (EPO906) with pegylated liposomal doxorubicin in platinum-refractory or -resistant patients with recurrent epithelial ovarian, primary fallopian tube, or primary peritoneal cancer.

PURPOSE: This study compared the efficacy and safety of patupilone with those of pegylated liposomal doxorubicin (PLD) in patients with platinum-refractory or -resistant epithelial ovarian, primary fallopian tube, or primary peritoneal cancer. PATIENTS AND METHODS: Patients with three or fewer prior regimens were eligible if they had received first-line taxane/platinum-based combination chemotherapy and were platinum refractory or resistant. Patients were randomly assigned to receive patupilone (10 mg/m(2) intravenously every 3 weeks) or PLD (50 mg/m(2) intravenously every 4 weeks). RESULTS: A total of 829 patients were randomly assigned (patupilone, n = 412; PLD, n = 417). There was no statistically significant difference in overall survival (OS), the primary end point, between the patupilone and PLD arms (P = .195; hazard ratio, 0.93; 95% CI, 0.79 to 1.09), with median OS rates of 13.2 and 12.7 months, respectively. Median progression-free survival was 3.7 months for both arms. The overall response rate (all partial responses) was higher in the patupilone arm than in the PLD arm (15.5% v 7.9%; odds ratio, 2.11; 95% CI, 1.36 to 3.29), although disease control rates were similar (59.5% v 56.3%, respectively). Frequently observed adverse events (AEs) of any grade included diarrhea (85.3%) and peripheral neuropathy (39.3%) in the patupilone arm and mucositis/stomatitis (43%) and hand-foot syndrome (41.8%) in the PLD arm. CONCLUSION: Patupilone did not demonstrate significant improvement in OS compared with the active control, PLD. No new or unexpected serious AEs were identified.

Patupilone (epothilone B) for recurrent glioblastoma: clinical outcome and translational analysis of a single-institution phase I/II trial.

BACKGROUND: Patients with glioblastoma (GBM) inevitably develop recurrent or progressive disease after initial multimodal treatment and have a median survival of 6-9 months from time of progression. To date, there is no accepted standard treatment for GBM relapse or progression. Patupilone (EPO906) is a novel natural microtubule-stabilizing cytotoxic agent that crosses the blood-brain barrier and has been found to have preclinical activity in glioma models. METHODS: This is a single-institution, early-phase I/II trial of GBM patients with tumor progression who qualified for second surgery with the goal of evaluating efficacy and safety of the single-agent patupilone (10 mg/m(2), every 3 weeks). Patients received patupilone 1 week prior to second surgery and every 3 weeks thereafter until tumor progression or toxicity. Primary end points were progression-free survival (PFS) and overall survival (OS) at 6 months as well as patupilone concentration in tumor tissue. Secondary end points were toxicity, patupilone concentration in plasma and translational analyses for predictive biomarkers. RESULTS: Nine patients with a mean age of 54.6 ± 8.6 years were recruited between June 2008 and April 2010. Median survival and 1-year OS after second surgery were 11 months (95% CI, 5-17 months) and 45% (95% CI, 14-76), respectively. Median PFS was 1.5 months (95% CI, 1.3-1.7 months) and PFS6 was 22% (95% CI, 0-46), with 2 patients remaining recurrence-free at 9.75 and 22 months. At the time of surgery, the concentration of patupilone in tumor tissue was 30 times higher than in the plasma. Tumor response was not predictable by the tested biomarkers. Treatment was generally well tolerated with no hematological, but cumulative, though reversible sensory neuropathy grade ≤3 was seen in 2 patients (22%) at 8 months and grade 4 diarrhea in the 2nd patient (11%). Non-patupilone-related peri-operative complications occurred in 2 patients resulting in discontinuation of patupilone therapy. There were no neurocognitive changes 3 months after surgery compared to baseline. CONCLUSIONS: In recurrent GBM, patupilone can be given safely pre- and postoperatively. The drug accumulates in the tumor tissue. The treatment results in long-term PFS in some patients. Patupilone represents a valuable novel compound which deserves further evaluation in combination with radiation therapy in patients with GBM.

Conversion of self-assembled monolayers into nanocrystalline graphene: structure and electric transport.

Graphene-based materials have been suggested for applications ranging from nanoelectronics to nanobiotechnology. However, the realization of graphene-based technologies will require large quantities of free-standing two-dimensional (2D) carbon materials with tunable physical and chemical properties. Bottom-up approaches via molecular self-assembly have great potential to fulfill this demand. Here, we report on the fabrication and characterization of graphene made by electron-radiation induced cross-linking of aromatic self-assembled monolayers (SAMs) and their subsequent annealing. In this process, the SAM is converted into a nanocrystalline graphene sheet with well-defined thickness and arbitrary dimensions. Electric transport data demonstrate that this transformation is accompanied by an insulator to metal transition that can be utilized to control electrical properties such as conductivity, electron mobility, and ambipolar electric field effect of the fabricated graphene sheets. The suggested route opens broad prospects toward the engineering of free-standing 2D carbon materials with tunable properties on various solid substrates and on holey substrates as suspended membranes.

Design of selective peptidomimetic agonists for the human orphan receptor BRS-3.

New tool substances may help to unravel the physiological role of the human orphan receptor BRS-3 and its possible use as a drug target for the treatment of obesity and cancer. In continuation of our work on BRS-3, the solid- and solution-phase synthesis of a library of low molecular weight peptidomimetic agonists based on the recently developed short peptide agonist 4 is described. Functional potencies of the compounds were determined measuring calcium mobilization in a fluorometric imaging plate reader (FLIPR) assay. Focusing on the N-terminus, the d-Phe-Gln moiety of 4 was modified in a combinatorial SAR-oriented medicinal chemistry approach. With the incorporation of N-arylated glycine and alanine building blocks azaglycine, piperazine, or piperidine and the synthesis of semicarbazides and semicarbazones, a number of highly potent and selective compounds with a reduced number of peptide bonds were obtained, which also should have enhanced metabolic stability.

Vascular endothelial growth factor mediated angiogenic potential of pancreatic ductal carcinomas enhanced by hypoxia: an in vitro and in vivo study.

Angiogenesis in pancreatic ductal adenocarcinomas depends on the presence of angiogenic factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) and is thought to be stimulated by hypoxia. We tested the angiogenic potential of 9 cell lines of pancreatic ductal carcinoma origin by screening mRNA and protein expression of VEGF and bFGF and the release of VEGF into culture medium under normoxic and hypoxic (5% or 0.2% O2) conditions. Angiogenic activity was determined using 2- and 3-D endothelial cell assays. Furthermore, VEGF expression and tumor vascularization were studied in human pancreatic carcinoma tissues from orthotopic xenografts and resection specimens. All cell lines expressed (mRNA, protein) and secreted VEGF, whereas bFGF was only found in 3 cell lines and was secreted into the medium in low concentrations. In addition to the dominant isoforms VEGF121,VEGF165 and VEGF189, 2 isoforms described recently, VEGF145 and VEGF183, were detected. Severe hypoxia (0.2% O2), but not moderate hypoxia (5% O2) raised VEGF mRNA expression and protein secretion in 7/9 and 5/9 cell lines, respectively. Conditioned media from 7/9, 6/9, 8/9 and 7/9 cell lines stimulated endothelial cell proliferation under normoxic (24 and 48 hr) or hypoxic (24 hr, 0.2% and 48 hr 5% O2) conditions, respectively. Conditioned media from 4/9 cell lines also induced capillary-like sprouting under normoxic conditions and from 6/9 under hypoxic (0.2% O2) conditions. In xenografted carcinoma tissues microvessel density was found not to be increased around areas of ischemic necrosis. In resected ductal carcinomas showing tumor necrosis VEGF expression and microvessel density were only increased in 3/12 and 2/13 cases, respectively. In conclusion, in vitro most pancreatic ductal carcinomas show a distinct VEGF related angiogenic potential, as demonstrated by 2- and 3-D endothelial cell proliferation, which may be promoted by severe hypoxia. Surprisingly, perinecrotic tumor areas, which are supposed to be hypoxic, only rarely showed the expected increase in microvessel density and VEGF expression.

Systematic optimization of a lead-structure identities for a selective short peptide agonist for the human orphan receptor BRS-3.

The orphan receptor, human bombesin receptor subtype 3 (BRS-3) was assigned to the G-protein coupled bombesin receptor family because of its high sequence homology with the neuromedin B receptor (NMB-R) and gastrin-releasing peptide receptor (GRP-R). Since its pharmacology is stiIl unknown, new highly potent and selective tool-substances are needed, that may be able to elucidate its possible role in obesity and cancer. We have performed structure activity relationship studies on the high affinity peptide agonists [D-Phe6,beta-Ala11,Phe13,Nle14]Bn(6-14) and [D-Phe6,Phe13]Bn(6-13)propylamide, using their ability to mobilize intracellular calcium in BRS-3 transfected CHOGa-16 cells combined with receptor binding studies. It was demonstrated that for [D-Phe,beta-Ala11,Phe13,Nle14]Bn(6-14) the side chains of the residues Trp8 and Phe13, and to a smaller extent beta-Ala11, are the important amino acid side chains for receptor activation and binding, however for [D-Phe6,Phe13]Bn(6-13) propylamide His12 seems to be more important than Phe13. C-and N-terminal deletions and amino acid substitutions allowed further understanding. It was demonstrated that substitution of His 12 by Tyr leads to a high selectivity towards GRP-R. Using the acquired information, a small tetrapeptide library was designed with compounds presenting Trp and Phe at varying stereochemistry and distances, which led to the discovery of the lead-structure H-D-Phe-Gln-D-Trp-Phe-NH2. Systematic SAR revealed the important structural features of this peptide, C-terminal optimization resulted in the highly active and selective BRS-3 agonist H-D-Phe-Gln-D-Trp-1-(2-phenylethyl)amide. In summary, the size of the peptide was reduced from 8 or 9 amino acids to a tripeptide for BRS-3.