Bioequivalence and Bioavailability Forum • DDI only in steady state

DDI only in steady state [Design Issues]

posted by Helmut – Vienna, Austria, 2014-12-08 18:43 (4221 d 10:27 ago) – Posting: # 14016
Views: 10,282

Hi Dan,

❝ In case linear PK applies for drug1 and drug2 a single-dose study is sufficient, otherwise I need to investigate steady state PK, right?

Nope. DDI should always be performed with the highest generally recommended dose in steady state (GL Section 5.4.3).

❝ […] Since the same route of elimination is partly used there could be a kind of competition. Could this be detected after single dose administration or do you need staedy state PK?

Exactly. See 5.4.4 of the guideline. It might well be that you see little effect after a single dose because the enzyme system needs some time to get activated.

—
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:

drug-drug interaction in steady state? Dr_Dan 2014-12-08 17:31
- DDI only in steady stateHelmut 2014-12-08 17:43
  - DDI only in steady state Dr_Dan 2014-12-08 18:15
    - DDI only in steady state Helmut 2014-12-08 18:30
      - DDI only in steady state felipeberlinski 2014-12-18 17:37
        
        DDI only in steady state Helmut 2014-12-18 17:59
      - DDI only in steady state Dr_Dan 2015-01-07 15:42
        
        DDI active wash-out Dr_Dan 2015-01-09 12:04
        
        DDI active wash-out nobody 2015-01-09 15:03
        DDI active wash-out Dr_Dan 2015-01-09 15:59
        
        DDI active wash-out nobody 2015-01-09 16:38