Nevertheless, a series of quality criteria have been introduced, keeping in mind the specific requirements of the REACH legislation, such as scientific validity (with two independent sets of compounds for validation), and clear, transparent documentation.
According to this definition, the relevant targets that do not appear in the top m ranked targets receive a precision score of 0. In the end, the averaged values of the PR n, RE n, F n and PR' for all compounds of validation datasets were reported.
Although this early stage screening allowed identification of neuroprotective compounds, further validation of hits from this assay will be necessary in higher vertebrate models of ALS.
For "compound-out" validation we used 67 mixtures, which included 34 new compounds (in total 1309 measurements); for "mixture-out" validation we used a set of 631 measurements, which included 27 new mixtures.
To validate the final HTS assay configuration, a screen of a small compound set (validation set) was run in triplicate.
However, the results of the same method, as well as of other methods for the "mixture-out" and "compound-out" validation protocols, are not significantly different from those calculated using the weighted sum of individual mixtures.
The final values used during the compound file validation and simulation studies were 4.596 × 10−4 cm/s, 37.6 µl/min/10 hepatocytes, and 2.55 l/h, respectively.
The results for the compound file validation are presented in the Supplementary Materials online section (Supplementary 1; Supplementary Tables S1 S4; Supplementary Figures S1 S4).
Initial compound file validation against clinical data showed that in the absence of detailed information on the supersaturation state following stomach emptying to intestine and the gut wall permeability, the model underpredicted the drug absorption and the elimination profile (data not shown).
Conversely, the new set of validation compounds included all compounds for which we found new data from the sources mentioned, and is thus probably more heterogeneous than the first validation set, which had the same data source.
