C L I N I C A L
T R I A L S
Blood to Plasma Ratio: An Important Determinant of the Pharmacokinetic Behavior of Drugs High affinity of a compound for red blood cells can lead to its sequestration in the cells but this property of certain drugs may be overlooked in the process of drug development. This article will illustrate that measuring drug concentration in both compartments - plasma and red blood cells is required for accurate pharmacokinetic assessment of drugs. Pallavi Limaye Director of Consulting, BioIVT
Steve McGreal Senior Scientist, BioIVT
T
he blood-to-plasma ratio (B/P ratio or Rb) is an important parameter in pharmacokinetics (PK) that reflects the distribution of a drug between red blood cells (RBCs) and plasma. It is defined as the ratio of the concentration of a drug in whole blood (CB) to the concentration of the drug in plasma (CP).
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P H AR M A F O C U S E U R O PE
ISSUE 02 - 2023