Month: October 2020

Difference Between PK and BE in Clinical Research?

PK and BE indicate pharmacokinetics and bio equivalent, respectively. The former is pharmacokinetics, which mainly is the drug concentration change after some time in blood. While BE is bioequivalence, it really is generally called and once the drug outcomes of two drugs in the organism are consistent, along with the index usually adopts PK index, which could be the Cmax and AUC drug concentration curve within the blood, falling between 80 and 125. Of course, sometimes BE is judged by dissolution curve and other pharmacodynamic indicators.

Generally, BE uses absolute bioavailability or relative bioavailability, while PK mainly collects blood/urinary drug concentration to have pharmacokinetic parameters (like half-life, peak concentration, Peak time, clearance rate, apparent distribution, bioavailability, etc.). Pharmacokinetics collects data by different doses, drug cycles, genders, races, health groups, drug administration etc.; while bioequivalence is expressed using pharmacokinetic parameters – the region under the curve (AUC), peak concentration (Cmax).

The function of the experimental design between two differs from the others, with regards to generic drugs or modified dosage forms. Therefore, you will find generally two preparations for BE, you are the reference preparation, another is the self-developed preparation, to check their relative bioavailability or absolute bioavailability and discover whether the drug is equivalent.

According to the registration requirements, PK and BE have to carry out (I take chemical drugs for example):

  1. PK: mainly for chemical drugs Class 1/2/3, except 1.6 and 3.4. It is put into single-dose, low-medium-high three-dose group and multiple doses. For Class 5, controlled release formulations, a comparative study of pharmacokinetics is necessary.
  2. BE: BE studies are needed for Class 5 and 6 for oral preparations.
    For precisely how to implement PK and BE, please make reference to these two guiding principles.

People on this field think of it as pharmacodynamics or Pharmacokinetics. Now pharmacokinetics has grown to be an independent course; people during my department like to it is known as DMPK (the total name is Drug Metabolism and Pharmacokinetics).
The traditional and classic specification of Pharmacokinetics refers back to the establishment of dynamic functions or model equations with mathematical method, which describes the disposition process after drugs entering the entire body. Pharmacokinetics is in reality a synthetic vocabulary. The two elements of the roots represent “drugs” and “kinetics”. Together, they are often called pharmacokinetics. It is universally accepted that mathematical methods and model equations would be the foundations of Pharmacokinetics.

Traditional Pharmacokinetics are yet to developed because the statistical Moment and compartmental analysis are mature, while its mathematical meaning is developing rapidly. The most intuitive reflection could be the pharmacokinetics (PK) – pharmacodynamics (PD) modelling and Population pharmacokinetics. Even the two branches of pharmacokinetics, and also the use of various other pharmacy mathematical methods, gave birth to an emerging marginal discipline, Pharmacometrices.