Purpose
To evaluate the ability of human airway epithelial cell layers and a simple rat isolated perfused lung (IPL) model to predict pulmonary drug absorption in rats
in vivo
.
Method
The ...permeability of seven compounds selected to possess a range of lipophilicity was measured in two airway cell lines (Calu-3 and 16HBE14o-), in normal human bronchial epithelial (NHBE) cells and using a simple isolated perfused lungs (IPL) technique. Data from the cell layers and
ex vivo
lungs were compared to published absorption rates from rat lungs measured
in vivo
.
Results
A strong relationship was observed between the logarithm of the
in vivo
absorption half-life and the absorption half-life in the IPL (
r
= 0.97; excluding formoterol). Good log-linear relationships were also found between the apparent first-order absorption rate
in vivo
and cell layer permeability with correlation coefficients of 0.92, 0.93, 0.91 in Calu-3, 16HBE14o- and NHBE cells, respectively.
Conclusion
The simple IPL technique provided a good prediction of drug absorption from the lungs, making it a useful method for empirical screening of drug absorption in the lungs. Permeability measurements were similar in all the respiratory epithelial cell models evaluated, with Calu-3 having the advantage for routine permeability screening purposes of being readily availability, robust and easy to culture.
The transient receptor potential (subfamily M, member 8; TRPM8) is a nonselective cation channel localized in primary sensory neurons, and is a candidate for cold thermosensing, mediation of cold ...pain, and bladder overactivity. Studies with TRPM8 knockout mice and selective TRPM8 channel blockers demonstrate a lack of cold sensitivity and reduced cold pain in various rodent models. Furthermore, TRPM8 blockers significantly lower body temperature. We have identified a moderately potent (IC50 = 103 nM), selective TRPM8 antagonist, PF-05105679 (R)-3-(1-(4-fluorophenyl)ethyl)(quinolin-3-ylcarbonyl)aminomethylbenzoic acid. It demonstrated activity in vivo in the guinea pig bladder ice water and menthol challenge tests with an IC50 of 200 nM and reduced core body temperature in the rat (at concentrations >1219 nM). PF-05105679 was suitable for acute administration to humans and was evaluated for effects on core body temperature and experimentally induced cold pain, using the cold pressor test. Unbound plasma concentrations greater than the IC50 were achieved with 600- and 900-mg doses. The compound displayed a significant inhibition of pain in the cold pressor test, with efficacy equivalent to oxycodone (20 mg) at 1.5 hours postdose. No effect on core body temperature was observed. An unexpected adverse event (hot feeling) was reported, predominantly periorally, in 23 and 36% of volunteers (600- and 900-mg dose, respectively), which in two volunteers was nontolerable. In conclusion, this study supports a role for TRPM8 in acute cold pain signaling at doses that do not cause hypothermia.
Purpose
To evaluate the behaviour of an oral matrix modified release formulation in the canine gastrointestinal tract, and establish if a mechanical weakness previously observed in clinical studies ...would have been identified in the dog model.
Materials and Methods
In vitro
release profiles were obtained for two modified release matrix tablets containing UK-294,315, designed to release over either 6 (formulation A) or 18 (formulation B) hours. Tablets were labelled with
153
samarium and
in vivo
pharmacoscintigraphy studies were performed in four beagle dogs in the fasted state for both formulations, and following ingestion of an FDA high fat meal for formulation B.
Results
The matrix tablet formulations displayed significantly different
in vitro
release profiles (
F
2
< 50), with time to 80% release for formulation A and B of 406 and 987 min respectively. Complete
in vivo
disintegration occurred at 339 ± 181 and 229 ± 171 for formulation A and B respectively in the fasted state, and at 207 ± 154 min for formulation B in the fed state, in disagreement with
in vitro
release.
Conclusion
The fed/fasted dog model would have predicted a lack of physical robustness in the matrix tablet formulation B, however it would not have predicted the clear fed/fasted effects on performance observed previously in man.
The present work aimed to differentiate between
in vitro
dissolution profiles of ibuprofen as input for GastroPlus™ and to see the impact on systemic exposure.
In vitro
dissolution profiles of ...ibuprofen obtained under low- and high-buffered dissolution media were used as input using the z-factor approach. In a second step, a customized surface pH calculator was applied to predict the surface pH of ibuprofen under these low- and high-buffered dissolution conditions. These surface pH values were adopted in GastroPlus™ and simulations were performed to predict the systemic outcome. Simulated data were compared with systemic data of ibuprofen obtained under fasted state conditions in healthy subjects. The slower dissolution rate observed when working under low-buffered conditions nicely matched with the slower dissolution rate as observed during the clinical aspiration study and was in line with the systemic exposure of the drug. Finally, a population simulation was performed to explore the impact of z-factor towards bioequivalence (BE) criteria (so-called safe space). Concerning future perspectives, the customized calculator should be developed in such a way to make it possible to predict the dissolution rate (being informed by the particle size distribution) which, in its turn, can be used as a surrogate to predict the USP2 dissolution curve. Subsequently, validation can be done by using this profile as input for PBPK platforms.
Graphical Abstract
The objective of the research was to establish the capability of the Intelisite capsule to deliver the probe drugs, theophylline and frusemide, in the form of split immediate release (IR) tablets, to ...the small intestine and colon. The two probe drugs were administered together in an open, random, three-way crossover study in eight healthy volunteers, comparing absorption following Intelisite delivery in the small bowel and colon to conventional IR dosing. Gamma scintigraphy was employed to monitor the gastrointestinal transit and activation of the Intelisite capsule. Standard pharmacokinetic parameters, and the percentage remaining in the capsules post defecation were determined. The Intelisite capsule was well tolerated in human volunteers and successfully activated on 15/16 occasions. Pharmacoscintigraphy showed internal marker release from the Intelisite capsule to be ∼10-fold faster in the small intestine than in the colon. Theophylline and frusemide were both well absorbed following Intelisite activation in the small intestine, whereas complete colonic absorption was only observed in 1/7 subjects for theophylline, and 0/7 subjects for frusemide. The probe drugs were successfully delivered in particulate form from the Intelisite capsule in the small intestine and produced expected pharmacokinetic profiles. However drug release in the colon was incomplete and variable possibly due to: low water content, poor mixing, and a high loading dose.
Purpose
The aim of this study was to evaluate clearance from the buccal cavity and pharmacokinetic profiles of a sublingual spray formulation in the dog, to assist in interpretation of future ...pharmacokinetic studies.
Methods
Radiolabelled buprenorphine in a spray formulation (400 μg/100 μl in 30% ethanol) was administered sublingually to four beagle dogs, and the residence in the oral cavity was determined using gamma scintigraphy. Pharmacokinetic sampling was performed to facilitate correlation of location of dose with significant pharmacokinetic events.
Results
Scintigraphic imaging revealed that clearance of the formulation from the oral cavity was rapid, with a mean
T
50%
clearance of 0.86 ± 0.46 min, and
T
80%
clearance of 2.75 ± 1.52 min. In comparison, absorption of buprenorphine was relatively slow, with a
T
max
of 0.56 ± 0.13 h. Good buccal absorption despite short residence time can be explained by lipophilicity of buprenorphine enabling rapid sequestration into the oral mucosa, prior to diffusion and absorption directly into systemic circulation.
Conclusion
This study demonstrated rapid clearance of a sublingual solution from the canine oral cavity, with
T
50%
similar to results previously reported in man, providing initial confidence in using a conscious dog model to achieve representative residence times for a sublingual solution.
A new series of carbapenems, having a saturated or partially unsaturated heterocycle at C-2, has been synthesised. The in vitro antibacterial activity of these compounds and their stability to human ...dehydropeptidase-1 (DHP-1) are described. The stereochemistry of the C-2 side-chain and the presence of a double bond in the heterocycle were shown to have significant effects on the stabilities of the compounds to DHP-1.
The synthesis, antibacterial activity and stability to human dehydropeptidase-1 (DHP-1) of three small series of carbapenems carrying carbon-linked substituents at C-2 are described. C-2 Ethenyl ...carbapenems showed moderate antibacterial activity but poor stability to DHP-1. C-2 Oxyiminomethyl carbapenems demonstrated variable activity and stability. C-2 α-(Hydroxy)benzyl carbapenems were the most promising and showed good potency and DHP-1 stability.
Background: Although diffuse large B cell lymphoma (DLBCL) can be cured using immuno-chemotherapy, 40% of patients experience relapse or refractory disease. Large-scale profiling studies have mainly ...focused on DLBCL at diagnosis, resolving different outcome groups based on gene expression (e.g. cell-of-origin (COO) or molecular high grade), MYC/BCL2 translocations (double-hit lymphoma) or gene mutations and copy number aberrations (Schmitz et al, NEJM 2018; Chapuy et al, Nature Medicine 2018). In comparison, longitudinal studies have been hindered by the limited availability of sequential biopsy samples. To date, the relapse-specific gene mutations identified are limited and inconsistent across studies. In our study, we have focussed attention on the changes in gene expression profile (GEP) accompanying DLBCL relapse.
Methods: We retrospectively collected archival paired diagnostic/relapse formalin fixed paraffin embedded tumor biopsies from 38 de novo DLBCL patients collected from multiple UK sites treated with rituximab-based immuno-chemotherapy, where partial or complete remission was reported following treatment. COO classification was performed by the Lymph2Cx assay on NanoString to distinguish activated B-cell-like (ABC) and germinal center B-cell-like (GCB) subtypes. The Ion AmpliSeq™ Transcriptome Human Gene Expression Kit was used to measure the expression levels of > 20,000 genes on the paired samples.
Results: COO remained stable from diagnosis to relapse in 17 ABC-ABC pairs, 11 GCB-GCB pairs and 4 unclassified (UNC)-UNC pairs. Frank COO switching was observed in 6 cases (1 ABC-GCB, 2 ABC-UNC, 2 GCB-UNC, 1 UNC-ABC). Pairs with stable COO were taken forward for further analysis. Gene expression analysis using the limma R package identified 163 and 136 genes as differentially expressed (DE) (p <= 0.01 and absolute log2FC > 1) between the diagnostic and relapse biopsies in ABC and GCB tumors respectively, with only a one gene overlap. Gene Set Enrichment Analysis further suggested that ABC and GCB relapses are mediated via different mechanisms, with tumor growth and proliferation signatures enriched in ABC relapses, whilst adaptive immunity-related signatures accompanied GCB relapses.
Next, we aimed to utilise our relapse-specific genes to identify outcome predictors at diagnosis using publicly available GEP datasets. In order to increase our discovery power and accuracy, a larger set of DE genes from the paired differential analysis (796 genes in ABC pairs and 387 from GCB pairs) were selected (p <= 0.05) and subsequently used in a training cohort (GEP from Reddy et al, Cell 2017). The Prediction Analysis for Microarrays R (PAMR) algorithm identified a 30-gene signature within DE genes from ABC pairs (Fig1.A), capable of separating the 249 ABC cases into 136 low and 113 high-risk cases with significantly inferior overall survival (Hazard Ratio (HR)=1.89, log-rank p=0.0017, measure of goodness-of-fit C-index=0.71; Fig1.B). No equivalent signature was found in the GCB cases using this approach.
The prognostic significance of this 30-gene discriminator was successfully validated using a linear predictor in two independent GEP datasets: 1) a population-based cohort (Lenz et al, NEJM 2008) with 93 R-CHOP-treated ABC cases identifying 47 low and 46 high-risk cases (HR=1.92, p=0.046, C-index=0.77; Fig1.C) and 2) a clinical trial dataset (REMoDL-B, Davies et al, Lancet Oncol 2019) with 255 ABC cases identifying 110 low and 145 high-risk ABC cases (HR=1.95, p=0.0051, C-index=0.70; Fig1.D).
Conclusions: Here we describe a 30-gene discriminator in ABC-DLBCL, derived from genes differentially expressed between diagnosis and relapse, that allowed the definition of clinically distinct high and low risk subgroups in ABC-DLBCLs at diagnosis. The clinical translation of such a tool may be useful to guide therapy for this unfavourable subgroup of ABC-DLBCLs. Validation of this signature is currently underway in additional datasets and further study is required to understand the contribution of these genes in DLBCL pathology.
Display omitted
Korfi:Roche: Consultancy. Burton:Celgene: Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees. Rule:TG Therapeutics: Consultancy, Honoraria; Napp: Consultancy; Kite: Consultancy; Pharmacyclics: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Sunesis: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Astra-Zeneca: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Crosbie:Janssen: Honoraria. Scott:Celgene: Consultancy; Janssen: Consultancy, Research Funding; NanoString: Patents & Royalties: Named inventor on a patent licensed to NanoSting Institution, Research Funding; Roche/Genentech: Research Funding. Rimsza:NanoSting: Patents & Royalties: Named inventor on a patent licensed to NanoSting Institution. Davies:Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding; Bayer: Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Research Funding; Karyopharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Research Funding; Acerta Pharma: Honoraria, Research Funding; ADCT Therapeutics: Honoraria, Research Funding; BioInvent: Research Funding; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; MorphoSys AG: Honoraria, Membership on an entity's Board of Directors or advisory committees. Gribben:Abbvie: Consultancy, Honoraria, Research Funding; Acerta/Astra Zeneca: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding. Okosun:Gilead Sciences: Honoraria, Research Funding. Johnson:Epizyme: Honoraria, Research Funding; Novartis: Honoraria; Kite: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria; Boehringer Ingelheim: Honoraria; Takeda: Honoraria; Genmab: Honoraria; Celgene: Honoraria; Incyte: Honoraria. Fitzgibbon:Epizyme: Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Speakers Bureau.
PDF
