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1.
PLoS One ; 16(9): e0257477, 2021.
Article in English | MEDLINE | ID: mdl-34555055

ABSTRACT

GPR40 (FFAR1) is a promising target for the managing type 2 diabetes (T2D). The most advanced GPR40 agonist TAK-875 exhibited satisfactory glucose-lowering effects in phase II and III studies. However, the phase III studies of TAK-875 revealed drug-induced liver injury (DILI). It is unknown whether DILI is a consequence of a specific GPR40 agonist or is an inherent feature of all GPR40 agonists. CPL207280 is a novel GPR40 agonist that improves diabetes in Zucker Diabetic Fatty (ZDF) rats, Goto Kakizaki (GK) rats and db/db mice. In this report, the DILI-related toxicity of CPL207280 was compared directly with that of TAK-875. In vitro studies evaluating hepatic biliary transporter inhibition, mitochondrial function, and metabolic profiling were performed in hepatocytes from different species. The long term toxicity of CPL207280 was studied in vivo in rats and monkeys. Activity of CPL207280 was one order of magnitude lesser than that of TAK-875 for the inhibition of bile acid transporters. CPL207280 had a negligible effect on the hepatic mitochondria. In contrast to TAK-875, which was metabolized through toxic glucuronidation, CPL207280 was metabolized mainly through oxidation. No deleterious hepatic effects were observed in chronically treated healthy and diabetic animals. The study presents promising data on the feasibility of creating a liver-safe GPR40 agonist. Additionally, it can be concluded that DILI is not a hallmark of GPR40 agonists; it is linked to the intrinsic properties of an individual agonist.


Subject(s)
Benzofurans , Hypoglycemic Agents , Sulfones , Animals , Blood Glucose , Diabetes Mellitus, Type 2 , Male , Mice , Rats
2.
Int J Toxicol ; 35(4): 438-53, 2016 07.
Article in English | MEDLINE | ID: mdl-27098749

ABSTRACT

BMX-001, a manganese porphyrin that has anti-inflammatory, antioxidant, and antitumor properties, is being developed as a potential therapeutic for high-grade glioma (HGG) and head and neck (H&N) cancer. An IND has been opened for BMX-001 in the treatment of HGG (NCT02655601) and another is in preparation for H&N. The safety of BMX-001 has been evaluated in a battery of nonclinical Good Laboratory Practice (GLP)-compliant studies. Systemic toxicity has been evaluated using the intended cGMP product administered subcutaneously for periods of up to 5 weeks in both the mouse and the monkey and included toxicokinetic evaluations to characterize systemic exposure and tissue distribution and clearance of BMX-001. In additional GLP studies, BMX-001 was not irritating to the skin or eye and caused no changes in cardiac rate or rhythm or blood pressure. Mixed results for genotoxicity were seen with the weight of evidence indicating that BMX-001 poses no genotoxic risk in humans. In systemic mouse and monkey studies, loading/maintenance dose no observed adverse effect levels were 12/2 mg/kg/dose and 6/2 mg/kg/dose, respectively, with maintenance doses administered every 3 days after the initial loading dose. Systemic data were used to determine a Food and Drug Administration-approved safe starting dose for the initial clinical study in patients with HGG. BMX-001 was detected in analyzed tissues, including the brain, persisting well past the short plasma clearance period. The highest levels of BMX-001 were seen in the liver and kidneys, with amounts in these tissues returning to close to undetectable levels after a 2-week cessation of dosing.


Subject(s)
Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/toxicity , Metalloporphyrins/pharmacokinetics , Metalloporphyrins/toxicity , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/blood , Brain/metabolism , Eye/drug effects , Female , Guinea Pigs , Heart Rate/drug effects , Kidney/metabolism , Liver/metabolism , Macaca fascicularis , Male , Maximum Tolerated Dose , Metalloporphyrins/administration & dosage , Metalloporphyrins/blood , Mice , Mutagenicity Tests , Rabbits , Skin/drug effects
3.
Int J Toxicol ; 35(2): 243-51, 2016.
Article in English | MEDLINE | ID: mdl-26867944

ABSTRACT

This survey serves as the ninth in a series of toxicology salary surveys conducted at 3-year intervals and beginning in 1988. An electronic survey instrument was distributed to 5919 individuals including members of the Society of Toxicology, American College of Toxicology, and 23 additional professional organizations. Question items inquired about gender, age, degree, years of experience, certifications held, areas of specialization, society membership, employment and income. Overall, 1293 responses were received (response rate 21.8%). The results of the 2014 survey provide insight into the job market and career path for current and future toxicologists.


Subject(s)
Salaries and Fringe Benefits , Surveys and Questionnaires , Toxicology , Adult , Aged , Female , Humans , Male , Middle Aged , Workforce
4.
Int J Toxicol ; 35(2): 95-178, 2016.
Article in English | MEDLINE | ID: mdl-26755718

ABSTRACT

Formulation of nonclinical evaluations is a challenge, with the fundamental need to achieve multiples of the clinical exposure complicated by differences in species and routes of administration-specific tolerances, depending on concentrations, volumes, dosing regimen, duration of each administration, and study duration. Current practice to approach these differences is based on individual experience and scattered literature with no comprehensive data source (the most notable exception being our 2006 publication on this same subject). Lack of formulation tolerance data results in excessive animal use, unplanned delays in the evaluation and development of drugs, and vehicle-dependent results. A consulting firm, a chemical company, and 4 contract research organizations conducted a rigorous data mining operation of vehicle data from studies dating from 1991 to 2015, enhancing the data from this author's 2006 publication (3 of the six 2015 contributors were also 2006 contributors). Additional data were found in the published literature. The results identified 108 single-component vehicles (and 305 combination formulations) used in more than 1,040 studies across multiple species (dog, primate, rat, mouse, rabbit, guinea pig, minipig, pig, chick embryo, and cat) by multiple routes for a wide range of study durations. The tabulated data include maximum tolerated use levels by species, route, duration of study, dose-limiting toxicity where reported, review of the available literature on each vehicle, guidance on syringe selection, volume and pH limits by route with basic guidance on nonclinical formulation development, and guidance on factors to be considered in nonclinical route selection.


Subject(s)
Toxicity Tests , Animals , Dose-Response Relationship, Drug , Drug Administration Routes , Species Specificity
5.
Int J Toxicol ; 33(6): 490-7, 2014.
Article in English | MEDLINE | ID: mdl-25359732

ABSTRACT

The minimal inhibitory concentration (MIC) of an antimicrobial agent for a microbial population (MIC(50, obs) and MIC(90, obs)) is an interpolated value determined for antibacterial drugs by in vitro methods. Many studies have tried to determine the correlation between the MIC(50, obs) or MIC(90, obs) value and the physicochemical parameters to allow quantitaive structure activity relationship (QSAR) predictions of efficacy. A rigorous evaluation of approaches to this problem is presented here. In order to find a correlation between chemical structure and the derivatives of the MIC values for 9 indicatory bacterial strains, it is necessary to employ a number of physicochemical parameters in combination. Only an arithmetic expression composed of many features illustrating the chemical structure of the molecule can be linked to the ƒMIC(50, obs) value. This article demonstrated that, despite the complexity of the MIC value used as the end point, it is possible to validate the model in a limited extent.


Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Models, Theoretical , Bacteria/growth & development , Microbial Sensitivity Tests , Molecular Structure , Structure-Activity Relationship
6.
Int J Toxicol ; 32(1): 11-22, 2013.
Article in English | MEDLINE | ID: mdl-23160313

ABSTRACT

This survey serves as the eighth in a series of toxicology salary surveys conducted at 3-year intervals and beginning in 1988. An electronic survey instrument was distributed to 5800 individuals including members of the Society of Toxicology, American College of Toxicology, and 23 additional professional organizations. Question items inquired about gender, age, degree, years of experience, certifications held, areas of specialization, society membership, employment and income. Overall, 2057 responses were received (response rate 35.5%). The results of the 2012 survey provide insight into the job market and career path for current and future toxicologists.


Subject(s)
Salaries and Fringe Benefits , Toxicology/economics , Career Choice , Data Collection , Female , Humans , Male , Salaries and Fringe Benefits/statistics & numerical data , Salaries and Fringe Benefits/trends , Sex Factors , Surveys and Questionnaires , Unemployment/statistics & numerical data , Unemployment/trends , United States
7.
Int J Toxicol ; 31(1): 25-33, 2012.
Article in English | MEDLINE | ID: mdl-22215410

ABSTRACT

The correlation between 52 physicochemical parameters and mean residence time (MRT) for 27 drugs used in human and dog were investigated. The physicochemical parameter values calculated provided a basis for deriving a series of arithmetic expressions, which were used to build a mathematical model describing the relationship between them and the MRT values. From the entire set of analyzed parameters, a subset of 14 was identified that contributed to the derivation of an arithmetic expression: Log(PSA - WPSA + ACID) x [XlogP - (LogKp - EAxLn(Caco2 + AMINE + SAF))] + (AMIDE + IP - FG) - Ln(MW + PISA) the value of which is highly correlated with the MRT value in dogs (P < .001) and allowed prediction of the MRT predicted (MRT(pred)). In humans, no correlation was found that allowed the calculation of MRT(pred). These results indicate that predicting the pharmacokinetics of any specific drug for humans based on pharmacokinetic data obtained in the dog should be undertaken with knowledge of the inherent limitations.


Subject(s)
Models, Biological , Pharmacokinetics , Animals , Area Under Curve , Dogs , Humans , Pharmaceutical Preparations/metabolism
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