Experimental design on single-time-point high-throughput microsomal stability assay.
An experimental design for a single-time-point microsomal stability assay was evaluated as compared with multiple-time-point studies. Results obtained from single-time-point experiments are in excellent agreement with those from multiple time points. First-order reaction kinetics revealed rapid changes of predicted half-life from percent remaining of the parent compound at the inflection points, suggesting a maximum predictive limit for half-life. Selection of the incubation time in single-time-point assays is important to obtain balanced information for stable and unstable compounds. A short incubation time (e.g., 5 min) is most useful for differentiating between unstable compounds, which is beneficial to direct the synthetic efforts in projects with poor metabolic stability. A long incubation time (e.g., 30 min) is more applicable to a compound series with high metabolic stability. For screening purposes, a moderate incubation time (e.g., 15 min) is recommended to achieve good resolution and a sufficiently high maximum predictive limit for half-life. This study suggests that a single-time-point assay is sufficient for ranking compounds in early drug discovery. It increases throughput and reduces turnaround time and cost.
Di
Li
L
Wyeth Research, P.O. Box CN 8000, Princeton, New Jersey 08543-8000, USA. dil@wyeth.com
Kerns
Edward H
EH
Gao
Ning
N
Li
Susan Q
SQ
Huang
Youping
Y
Bourassa
Jim L
JL
Huryn
Donna M
DM
D000818:Animals; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D004364:Pharmaceutical Preparations / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012107:Research Design / Q000706:statistics & numerical data*
D004364:Pharmaceutical Preparations