Bioequivalence and Bioavailability Forum • NCA 'model independent'?

NCA 'model independent'? [Bioanalytics]

posted by Helmut – Vienna, Austria, 2007-08-11 22:09 (6095 d 04:42 ago) – Posting: # 972
Views: 10,897

Dear Dr. Shiv!

❝ <5% assumption is to again monitor concentration upto 5 half-lives.

❝ All the assumptions are model independent. Again, in BE studies only non-compartmental models are used.

I certainly agree with you that all guidelines recommend NCA for BE.
But we must not forget that NCA is not really independent from a PK model.
When you are talking about half-life, you are implying (at least for the ‘terminal’ phase within the profile) first order elimination.
The ‘5% rule’ is doubtful for a Michaelis-Menten type of elimination, and simply wrong for a zero-order process (e.g., ethanol).
So again, study planing in all its aspects (number and distribution of sampling points, length of sampling interval,…) must always be guided by a thorough knowledge of the drug’s PK.

—
Dif-tor heh smusma 🖖🏼 Довге життя Україна!
Helmut Schütz

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes

Complete thread:

PK Vs Analytical Charl 2007-07-23 10:44 [Bioanalytics]
- PK Vs Analytical Helmut 2007-07-23 18:04
  - PK Vs Analytical Charl 2007-07-24 10:31
    - PK Vs Analytical Helmut 2007-07-24 13:42
      - PK Vs Analytical Charl 2007-07-24 15:02
- PK Vs Analytical drshiv 2007-07-31 08:47
  - PK Vs Analytical Charl 2007-07-31 14:07
    - PK Vs Analytical drshiv 2007-08-07 16:37
      - NCA 'model independent'?Helmut 2007-08-11 20:09
        
        NCA 'model independent'? drshiv 2007-08-12 13:08
        
        Numerical integration Helmut 2007-08-12 18:51
        
        Numerical integration drshiv 2007-08-14 08:29