Pre-dose samples [Design Issues]

posted by Helmut Homepage – Vienna, Austria, 2020-01-09 12:36 (466 d 04:53 ago) – Posting: # 21069
Views: 1,766

Hi Pharma_88,

» A case of Steady state bioequivalence study in which dose is administered twice daily from Day XX to Day XX. Suppose Day 01 to Day 07 where on day 07 only morning dose will be administered.

This is only acceptable if you know that there are no circadian differences in PK. Otherwise, you have to administer both doses on day 7 as well and assess the complete 24 hours profile.

» As per guideline, at least 3 pre-dose samples are required to collect. But as we are administrating Drug twice daily, its is necessary to collect pre-dose for morning and evening both for few days i.e Day 01 (morning evening), Day 04 (morning evening) and Day 07 (Morning)?

The idea behind is to assess whether you reached (pseudo-) steady state.* Hence, pre-doses on the mornings of day 5, 6, 7.

» Also suggest for t.i.d. administration.


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