Bioequivalence and Bioavailability Forum • Concentration-time graphs and higher last sampling time point

Concentration-time graphs and higher last sampling time point [PK / PD]

posted by Smitha – India, 2018-11-29 12:22 (1967 d 19:54 ago) – Posting: # 19657
Views: 4,245

Hello all,

I have 2 questions on PK for a BE study

Sometimes, the last quantifiable concentration is higher than the preceding concentration in the elimination phase.
1. What would be the impact of such a profile?
2. Are there any regulatory requirements on how these need to be handled?
3. If the guideline or the CRO SOP does not address this issue, is it acceptable to accept the data as is? Does it need to be addressed in an SOP/protocol?
For a BE study, a window period is given for the sampling time points and usually most CROs use the scheduled time point if the sampling deviation is within the window period to plot the concentration-time graphs. The actual sampling time point is used in the graphs only if the sampling is outside the window period.
1. If the actual time-point is used even if the sampling deviation is within the window period, is it appropriate? Is there an impact on the PK data e.g AUC?
2. Are there any regulatory requirements on how these need to be handled?

Would appreciate the members opinions on the above points.

Thank you.

Regards,
Smitha

Concentration-time graphs and higher last sampling time pointSmitha 2018-11-29 11:22
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