Bioequivalence and Bioavailability Forum

Dear Priyanka!

❝ FDA suggests that if half-life is greater than 24 hours study can be truncated for 72 hrs. But in EU there is no cut off value like FDA. It suggests "A sampling period longer than 72 h is therefore not considered necessary for any immediate release formulation irrespective of the half life of the drug."

Exactly. You asked for EMA. They don’t give a damn about what the FDA said in 2003. If you want to submit a study in Europe, follow EMA’s rules.

❝ In the current study the half-life is 23 hrs. If we take 5 half-life's to complete sampling schedule it takes up to 120 hrs. But as per the EU longer than 72 is not required for immediate release formulations. Hence Can we consider truncation in this case?

What the heck are you trying to tell me? Is this sentence somehow difficult to comprehend?

A sampling period longer than 72 h is therefore not considered necessary for any immediate release formulation irrespective of the half life of the drug.

Truncation at 72 hours is easier and acceptable. We have fought for this option for many years. Love it or leave it; it’s up to you which design you want to use. I suggest to keep the total number of samples; you may ‘invest’ saved later samples in the area of C_max in order to reduce variability. If you want to go with a ‘classical’ design, don’t forget that your t_½ of 23 hours likely is a mean value. You have to cover 80% of AUC_∞.