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Cytochrome P450 inhibition assay

Understand the potential drug-drug interaction liabilities of your compounds by using our cytochrome P450 (CYP450) reversible inhibition assay for a range of isoforms.

The cytochrome P450 inhibition assay is one of our portfolio of in vitro ADME screening services. Cyprotex deliver consistent, high quality data with cost-efficiency that comes from a highly automated approach


Inhibition of cytochrome P450 (CYP450) enzymes

  • Cytochrome P450 are a family of enzymes which play a major role in the metabolism of drugs.
  • Assessment of the potential of a compound to inhibit a specific cytochrome P450 enzyme is important as co-administration of compounds may result in one or both inhibiting the other’s metabolism. This may affect plasma levels in vivo and potentially lead to adverse drug reactions or toxicity.
  • In vitro cytochrome P450 inhibition data are useful in designing strategies for investigating clinical DDI Studies.
  • Cyprotex's Cytochrome P450 Inhibition assays use industry accepted probe substrates and human liver microsomes.
  • In Cyprotex's Cytochrome P450 Inhibition assay, a decrease in the formation of the metabolites compared to the vehicle control is used to calculate an IC50 value (test compound concentration which produces 50% inhibition).
  cytochrome p450 inhibition
‘The effects of new drugs on well characterized drug metabolism reactions known to be specific for various human drug-metabolizing enzymes are routinely examined using in vitro approaches.’
1Obach RS, Walsky RL, Venkatakrishnan K, Gaman EA, Houston JB and Tremaine LM. (2006) JPET 316; 336-348.
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8 Nomeir AA et al. (2001) Drug Metab Dispos 29 (5); 748-53.
9 FDA Draft Guidance for Industry. Drug Interaction Studies – Study Design, Data Analysis, Implications for Dosing, and Labeling Recommendations (2012)
10 The European Medicines Agency (EMA) Guideline on the Investigation of Drug Interactions (Adopted in 2012)
11 Bjornsson TD et al. (2003) Drug Met Dispos 31; 815-832.
12 Stresser DM et al. (2000) Drug Metab Dispos 28; 1440-1448.

1 Obach RS et al. (2006) JPET 316; 336-348.
2 Bu HZ et al. (2001) Eur J Pharm Sci 12 (4); 447-52.
3 Turpeinen M et al. (2004) Drug Metab Dispos 32 (6); 626-631.
4 Back DJ et al. (1988) Br J Clin Pharmacol 26 (1); 23-29.
5 Dierks EA et al. (2001) Drug Metab Dispos 29 (1); 23-9.
6 Eagling VA et al. (1998) Br J Clin Pharmacol 45 (2); 107-114.
7 Moody GC et al. (1999) Xenobiotica 29 (1); 53-75.

cytochrome P450 inhibition

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This website was last updated
on 16th April 2014
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