RG7212 anti-TWEAK mAb inhibits tumor growth through inhibition of tumor cell proliferation and survival signaling and by enhancing the host antitumor immune response.

PURPOSE: To explore the role of TWEAK in tumor growth and antitumor immune response and the activity and mechanism of RG7212, an antagonistic anti-TWEAK antibody, in tumor models. EXPERIMENTAL DESIGN: TWEAK-induced signaling and gene expression were explored in tumor cell lines and inhibition of these effects and antitumor efficacy with RG7212 treatment was assessed in human tumor xenograft-, patient-derived xenograft, and syngeneic tumor models and phase I patients. Genetic features correlated with antitumor activity were characterized. RESULTS: In tumor cell lines, TWEAK induces proliferation, survival, and NF-κB signaling and gene expression that promote tumor growth and suppress antitumor immune responses. TWEAK-inducible CD274, CCL2, CXCL-10 and -11 modulate T-cell and monocyte recruitment, T-cell activation, and macrophage differentiation. These factors and TWEAK-induced signaling were decreased, and tumor, blood, and spleen immune cell composition was altered with RG7212 treatment in mice. RG7212 inhibits tumor growth in vivo in models with TWEAK receptor, Fn14, expression, and markers of pathway activation. In phase I testing, signs of tumor shrinkage and stable disease were observed without dose-limiting toxicity. In a patient with advanced, Fn14-positive, malignant melanoma with evidence of tumor regression, proliferation markers were dramatically reduced, tumor T-cell infiltration increased, and tumor macrophage content decreased. Antitumor activity, a lack of toxicity in humans and animals and no evidence of antagonism with standard of care or targeted agents in mice, suggests that RG7212 is a promising agent for use in combination therapies in patients with Fn14-positive tumors.

Identification of novel, potent and selective inhibitors of Polo-like kinase 1.

A series of pyrimidodiazepines was identified as potent Polo-like kinase 1 (PLK1) inhibitors. The synthesis and SAR are discussed. The lead compound 7 (RO3280) has potent inhibitory activity against PLK1, good selectivity against other kinases, and excellent in vitro cellular potency. It showed strong antitumor activity in xenograft mouse models.

High tumor levels of IL6 and IL8 abrogate preclinical efficacy of the γ-secretase inhibitor, RO4929097.

Interest continues to build around the early application of patient selection markers to prospectively identify patients likely to show clinical benefit from cancer therapies. Hypothesis generation and clinical strategies often begin at the preclinical stage where responder and nonresponder tumor cell lines are first identified and characterized. In the present study, we investigate the drivers of in vivo resistance to the γ-secretase inhibitor RO4929097. Beginning at the tissue culture level, we identified apparent IL6 and IL8 expression differences that characterized tumor cell line response to RO4929097. We validated this molecular signature at the preclinical efficacy level identifying additional xenograft models resistant to the in vivo effects of RO4929097. Our data suggest that for IL6 and IL8 overexpressing tumors, RO4929097 no longer impacts angiogenesis or the infiltration of tumor associated fibroblasts. These preclinical data provide a rationale for preselecting patients possessing low levels of IL6 and IL8 prior to RO4929097 dosing. Extending this hypothesis into the clinic, we monitored patient IL6 and IL8 serum levels prior to dosing with RO4929097 during Phase I. Interestingly, the small group of patients deriving some type of clinical benefit from RO4929097 presented with low baseline levels of IL6 and IL8. Our data support the continued investigation of this patient selection marker for RO4929097 and other types of Notch inhibitors undergoing early clinical evaluation.

Safety and pharmacokinetics of daclizumab in pediatric renal transplant recipients.

This study examined the safety and pharmacokinetics/pharmacodynamics of daclizumab in combination with mycophenolate mofetil (or azathioprine), corticosteroids, and cyclosporine or tacrolimus, in 61 pediatric renal allograft recipients in three age groups: less than or equal to five yr (n = 18), 6-12 yr (n = 18), and 13-17 yr (n = 25). The dosing regimen was daclizumab 1.0 mg/kg before transplantation, followed by four biweekly doses. The pharmacokinetics of daclizumab were described using NONMEM software. Median (range) estimated trough daclizumab levels achieved on day 56 (before dose 5) were 3.88 microg/mL (2.48-8.78), 4.54 microg/mL (1.79-18.7), and 4.94 microg/mL (0.05-10.6) in the less than or equal to five yr (n = 15), 6-12 yr (n = 17), and 13-17 yr (n = 22) age groups, respectively. Steady-state median (range) daclizumab exposures were 2040 mg x h/mL (1585-3778), 2757 mg x h/mL (1873-3494) and 3297 mg x h/mL (1705-6453), respectively. Saturation of the IL-2R occurred rapidly and was maintained for greater than or equal to three months after transplantation. Daclizumab was generally well-tolerated with no acute allergic or anaphylactic reactions, deaths or malignancies during the study. The proportion of patients who developed acute rejection at six and 12 months was 8.5% and 16.7%, respectively. This study shows that adding daclizumab at 1 mg/kg to standard immunosuppressive therapy provides safe and effective IL-2R blockade.

In vitro and in vivo activity of R547: a potent and selective cyclin-dependent kinase inhibitor currently in phase I clinical trials.

The cyclin-dependent protein kinases are key regulators of cell cycle progression. Aberrant expression or altered activity of distinct cyclin-dependent kinase (CDK) complexes results in escape of cells from cell cycle control, leading to unrestricted cell proliferation. CDK inhibitors have the potential to induce cell cycle arrest and apoptosis in cancer cells, and identifying small-molecule CDK inhibitors has been a major focus in cancer research. Several CDK inhibitors are entering the clinic, the most recent being selective CDK2 and CDK4 inhibitors. We have identified a diaminopyrimidine compound, R547, which is a potent and selective ATP-competitive CDK inhibitor. In cell-free assays, R547 effectively inhibited CDK1/cyclin B, CDK2/cyclin E, and CDK4/cyclin D1 (K(i) = 1-3 nmol/L) and was inactive (K(i) > 5,000 nmol/L) against a panel of >120 unrelated kinases. In vitro, R547 effectively inhibited the proliferation of tumor cell lines independent of multidrug resistant status, histologic type, retinoblastoma protein, or p53 status, with IC(50)s

Biological evaluation of a multi-targeted small molecule inhibitor of tumor-induced angiogenesis.

RO4396686 is a small molecule KDR, FGFR, and PDGFR inhibitor with good pharmacokinetic properties in rodents. In a mouse corneal neovascularization assay, this compound inhibited VEGF-induced angiogenesis. Tested in a H460a xenograft tumor model this agent effected significant tumor growth inhibition at doses as low as 50mg/kg.

RO4383596, an orally active KDR, FGFR, and PDGFR inhibitor: synthesis and biological evaluation.

(+/-)-1-(anti-3-Hydroxy-cyclopentyl)-3-(4-methoxy-phenyl)-7-phenylamino-3,4-dihydro-1H-pyrimido[4,5-d]pyrimidin-2-one (RO4383596) is a potent and selective inhibitor of the pro-angiogenic receptor tyrosine kinases KDR, FGFR, and PDGFR. This agent has an excellent pharmacokinetic profile and is highly efficacious in rodent models of angiogenesis upon oral administration.

Determinación del diámetro de tuberías mediante trazador

La determinación de las condiciones internas de las tuberías es un paso clave en el planeamiento, la operación y el mantenimiento de un sistema de distribución de agua. El deterioro en el interior de las mismas, se debe, generalmente, a la existencia de depósitos que se acumulan en sus paredes a lo largo del tiempo. Estos depósitos reducen el diámetro interno de las tuberías y aumentan las rugosisdades, reduciendo la capacidad hidráulica y acelerando la pérdida de calidad del agua. Tradicionalmente, los diámetros internos de las tuberías de un sistema de agua se definían de acuerdo a los estándares industriales de cañerías nuevas, pero este enfoque puede conducir a resultados inadecuados, porque el diámetro efectivo cambia con el tiempo. Se propone y analiza el método que utiliza la vitamina C como trazador para realizar ensayos in situ que determinen el diámetro de una tubería en servicio. Se presenta la técnica desarrollada por la Water & Electric Board’s Water Distribution System (EWEB) de Oregon, Estados Unidos y su experiencia llevada a cabo en Eugene, bajo condiciones de pocas tuberculosidades o incrustaciones. Demostrando que en éstas condiciones, el método es seguro, económico, no destructivo, preciso y confiable para determinar el diámetro medio efectivo de las tuberías

Determinación del diámetro de tuberías mediante trazador

La determinación de las condiciones internas de las tuberías es un paso clave en el planeamiento, la operación y el mantenimiento de un sistema de distribución de agua. El deterioro en el interior de las mismas, se debe, generalmente, a la existencia de depósitos que se acumulan en sus paredes a lo largo del tiempo. Estos depósitos reducen el diámetro interno de las tuberías y aumentan las rugosisdades, reduciendo la capacidad hidráulica y acelerando la pérdida de calidad del agua. Tradicionalmente, los diámetros internos de las tuberías de un sistema de agua se definían de acuerdo a los estándares industriales de cañerías nuevas, pero este enfoque puede conducir a resultados inadecuados, porque el diámetro efectivo cambia con el tiempo. Se propone y analiza el método que utiliza la vitamina C como trazador para realizar ensayos in situ que determinen el diámetro de una tubería en servicio. Se presenta la técnica desarrollada por la Water & Electric Boards Water Distribution System (EWEB) de Oregon, Estados Unidos y su experiencia llevada a cabo en Eugene, bajo condiciones de pocas tuberculosidades o incrustaciones. Demostrando que en éstas condiciones, el método es seguro, económico, no destructivo, preciso y confiable para determinar el diámetro medio efectivo de las tuberías