ToxEvaluator: an integrated computational platform to aid the interpretation of toxicology study-related findings

Attempts are frequently made to investigate adverse findings from preclinical toxicology studies in order to better understand underlying toxicity mechanisms. These efforts often begin with limited information, including a description of the adverse finding, knowledge of the structure of the chemical associated with its cause and the intended pharmacological target. ToxEvaluator was developed jointly by Pfizer and the Comparative Toxicogenomics Database (http://ctdbase.org) team at North Carolina State University as an in silico platform to facilitate interpretation of toxicity findings in light of prior knowledge. Through the integration of a diverse set of in silico tools that leverage a number of public and proprietary databases, ToxEvaluator streamlines the process of aggregating and interrogating diverse sources of information. The user enters compound and target identifiers, and selects adverse event descriptors from a safety lexicon and mapped MeSH disease terms. ToxEvaluator provides a summary report with multiple distinct areas organized according to what target or structural aspects have been linked to the adverse finding, including primary pharmacology, structurally similar proprietary compounds, structurally similar public domain compounds, predicted secondary (i.e. off-target) pharmacology and known secondary pharmacology. Similar proprietary compounds and their associated in vivo toxicity findings are reported, along with a link to relevant supporting documents. For similar public domain compounds and interacting targets, ToxEvaluator integrates relationships curated in Comparative Toxicogenomics Database, returning all direct and inferred linkages between them. As an example of its utility, we demonstrate how ToxEvaluator rapidly identified direct (primary pharmacology) and indirect (secondary pharmacology) linkages between cerivastatin and myopathy.

Rapid method for estimating the octanol--water partition coefficient (log P ow) by microemulsion electrokinetic chromatography

Several surfactant systems were evaluated based on their system constants determined by the solvation parameter model for the design of a surrogate chromatographic model for the rapid estimation of octanol-water partition coefficient (log Pow) by microemulsion electrokinetic chromatography. The system constant ratios responsible for the log Pow partition system are (nearly) the same as those for the microemulsion system containing sodium dodecyl sulfate (1.4% w/v), butan-1-ol (8% v/v) and heptane (1.2% v/v). Neutral and basic compounds are analyzed using a fused-silica capillary column with a 50 mM sodium phosphate-sodium borate (3:2) buffer at pH 10. Weakly acid compounds require the use of sulfonated silica capillary column and a 50 mM sodium phosphate buffer at pH 3. For 29 varied neutral and weakly basic compounds the average error between log Pow estimated using MEEKC and literature values was +/-0.12 over a log Pow range from 0.3 to 5.8.