The modeling framework successfully predicted survival in a phase III trial on the basis of capecitabine phase II data in CRC. It is a useful tool to support end-of-phase II decisions and design of phase III studies.

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TTG captured therapeutic benefit with bevacizumab in first-line CRC patients. Chinese ethnicity had no impact. Longitudinal tumor size data coupled with model-based approaches may offer a powerful alternative in the design and analysis of early clinical studies.

Atezolizumab, a humanized immunoglobulin G1 (IgG1) monoclonal antibody targeting human programmed death-ligand 1 (PD-L1), is US Food and Drug Administration (FDA) approved in metastatic urothelial carcinoma (MUC) and is being investigated in various malignancies. This analysis based upon 906 patients from two phase I and one phase II MUC studies, is the first report of the clinical pharmacokinetics (PK) and pharmacodynamics (PD) of atezolizumab. Atezolizumab exhibited linear PK over a dose range of 1-20 mg/kg, including the labeled 1,200 mg dose. The clearance, volume of distribution, and terminal half-life estimates from population pharmacokinetic (PopPK) analysis of 0.200 L/day, 6.91 L, and 27 days, respectively, were as expected for an IgG1. Exposure-response analyses did not identify statistically significant relationships with either objective response rate or adverse events of grades 3-5 or of special interest. None of the statistically significant covariates from PopPK (body weight, gender, antitherapeutic antibody, albumin, and tumor burden) would require dose adjustment.

BackgroundIleal lesions of Crohn's disease (CD) patients are abnormally colonized by pathogenic adherent-invasive Escherichia coli (AIEC) able to invade and to replicate within intestinal epithelial cells and macrophages.Principal FindingsWe report here the complete genome sequence of E. coli LF82, the reference strain of adherent-invasive E. coli associated with ileal Crohn's disease. The LF82 genome of 4,881,487 bp total size contains a circular chromosome with a size of 4,773,108 bp and a plasmid of 108,379 bp. The analysis of predicted coding sequences (CDSs) within the LF82 flexible genome indicated that this genome is close to the avian pathogenic strain APEC_01, meningitis-associated strain S88 and urinary-isolated strain UTI89 with regards to flexible genome and single nucleotide polymorphisms in various virulence factors. Interestingly, we observed that strains LF82 and UTI89 adhered at a similar level to Intestine-407 cells and that like LF82, APEC_01 and UTI89 were highly invasive. However, A1EC strain LF82 had an intermediate killer phenotype compared to APEC-01 and UTI89 and the LF82 genome does not harbour most of specific virulence genes from ExPEC. LF82 genome has evolved from those of ExPEC B2 strains by the acquisition of Salmonella and Yersinia isolated or clustered genes or CDSs located on pLF82 plasmid and at various loci on the chromosome.ConclusionLF82 genome analysis indicated that a number of genes, gene clusters and pathoadaptative mutations which have been acquired may play a role in virulence of AIEC strain LF82.

SummaryGenetic determinants that co-operate with type 1 pili to mediate invasion were sought for in adherentinvasive Escherichia coli strain LF82 isolated from a patient with Crohn's disease. Thus, we showed that flagella play a direct role in the adhesion process via active motility. In addition to downregulating type 1 pili expression, flagella also play an undefined role in strain LF82 invasion, which is not restricted to motility or flagellar structure, but could be related to co-ordinate expression of invasive determinants.

SummaryFliI is the peripheral membrane ATPase pivotal to the type III protein export mechanism underlying the assembly of the bacterial flagellum. Gel filtration and multiangle light scattering showed that purified soluble native FliI protein was in a monomeric state but, in the presence of ATP, FliI showed a propensity to oligomerize. Electron microscopy revealed that FliI assembles to a ring structure, the yield of which was increased by the presence of a non-hydrolysable ATP analogue. Single particle analysis of the resulting electron micrograph images, to which no symmetry was applied, showed that the FliI ring structure has sixfold symmetry and an external diameter of ª ª ª ª 10 nm. The oligomeric ring has a central cavity of 2.5-3.0 nm, which is comparable to the known diameter of the flagellar export channel into which export substrates feed. Enzymatic activity of the FliI ATPase showed positive co-operativity, establishing that oligomerization and enzyme activity are coupled. Escherichia coli phospholipids increased enzyme co-operativity, and in vitro cross-linking demonstrated that they promoted FliI multimerization. The data reveal central facets of the structure and action of the flagellar assembly ATPase and, by extension, the homologous ATPases of virulence-related type III export systems.

Standard endpoints often poorly predict overall survival (OS) with immunotherapies. We investigated the predictive performance of model-based tumor growth inhibition (TGI) metrics using data from atezolizumab clinical trials in patients with non-small cell lung cancer. OS benefit with atezolizumab versus docetaxel was observed in both POPLAR (phase II) and OAK (phase III), although progression-free survival was similar between arms. A multivariate model linking baseline patient characteristics and on-treatment tumor growth rate constant (KG), estimated using time profiles of sum of longest diameters (RECIST 1.1) to OS, was developed using POPLAR data. The model was evaluated to predict OAK outcome based on estimated KG at TGI data cutoffs ranging from 10 to 122 weeks. In POPLAR, TGI profiles in both arms crossed at 25 weeks, with more shrinkage with docetaxel and slower KG with atezolizumab. A log-normal OS model, with albumin and number of metastatic sites as independent prognostic factors and estimated KG, predicted OS HR in subpopulations of patients with varying baseline PD-L1 expression in both POPLAR and OAK: model-predicted OAK HR (95% prediction interval), 0.73 (0.63-0.85), versus 0.73 observed. The POPLAR OS model predicted greater than 97% chance of success of OAK (significant OS HR, < 0.05) from the 40-week data cutoff onward with 50% of the total number of tumor assessments when a successful study was predicted from 70 weeks onward based on observed OS. KG has potential as a model-based early endpoint to inform decisions in cancer immunotherapy studies. .