Science Inventory

The High Throughput Toxicokinetic (HTTK) R Package


Wambaugh, J. The High Throughput Toxicokinetic (HTTK) R Package. Presented at NCCT Computational Toxicology Communities of Practice Webinar, RTP, NC, June 27, 2019.


Webinar presentation given by EPA Scientist Dr. John Wambaugh for the 6/27/2019 NCCT Communities of Practice webinar on the High Throughput Toxicokinetic (HTTK) R Package.


Toxicokinetics (TK) provides a bridge between toxicity and exposure assessment by predicting tissue concentrations due to exposure, however traditional TK methods are resource intensive. Relatively high throughput TK (HTTK) methods have been used by the pharmaceutical industry to determine range of efficacious doses and to prospectively evaluate success of planned clinical trials. A key application of HTTK has been “reverse dosimetry” (also called Reverse TK or RTK). RTK can approximately convert in vitro HTS results to daily doses needed to produce similar levels in a human for comparison to exposure data. A new EPA open source R package (“httk”) is freely available on CRAN allows RTK and other statistical analyses. HTTK allows dosimetric adjustment of high-throughput screening (HTS) data across thousands of chemicals. New, chemical-specific in vitro experiments have been conducted by Cyprotex, using a revised protocol for measuring protein binding. Comparison between high throughput toxicokinetics (HTTK) predicted concentrations and in vivo data is a valuable approach for evaluation and establishing confidence. Recent analyses indicate that some properties (e.g. average and maximum concentration) can be predicted with confidence.The views expressed in this presentation are those of the author and do not necessarily reflect the views or policies of the US EPA.

Record Details:

Product Published Date:06/27/2019
Record Last Revised:08/14/2019
OMB Category:Other
Record ID: 345861