Bioequivalence and Bioavailability Forum

and what about power? [BE/BA News]

posted by Helmut  – Vienna, Austria, 2012-03-08 14:36 (4813 d 00:28 ago) – Posting: # 8236
Views: 22,554

Dear ElMaestro!

❝ In simple cases we might write something like P(Success) = P(BE AUC and Cmax)= P(BE AUC) * P(BE Cmax), but in reality Cmax and AUC are correlated and therefore the two components are not independent. It is implicitly assumed anyway when companies just ignore the less variable component and power the study for Cmax and assume that if Cmax is BE then AUC will be as well.

Yessir! If you want to step into murky waters:

KF Phillips
Power for Testing Multiple Instances of the Two One-sided Tests Procedure
Int J Biostat 5(1), 1–12 (2009)

❝ Now for the bi-phasic formulations. Here I am not sure what to do. […] One could of course try and ID the most variable of them (C_max,II?) …

I would say more likely C_max,I.

❝ … and power on basis of that but I would certainly not feel comfortable to relay the message to management that the chancee of success is 80% if the dimensioning is based on power consideration for just one of the three/four parameters.

❝ Finally, linear kinetics: How to assess it? What if something appears linear based on phase I but not really linear based on phase II?

Oh dear! Yes, that’s theoretically possible if partial AUCs are very different (e.g. saturation of enzymes). Do you want me to check my MPH-data? Linear PK within 10–60 mg based on AUC_0-t.

—
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:

• EMA: Q&A on biphasic MR products Helmut 2012-03-06 15:23 [BE/BA News] 
  • EMA: Q&A on biphasic MR products ElMaestro 2012-03-06 19:09
    • EMA: Q&A on biphasic MR products Helmut 2012-03-07 03:52
      • EMA: Q&A on biphasic MR products ElMaestro 2012-03-07 19:20
  • EMA vs. FDA d_labes 2012-03-07 10:26
    • MPH examples Helmut 2012-03-07 14:22
      • MPH examples d_labes 2012-03-07 16:18
        • MPH examples Helmut 2012-03-08 01:07
          • FDA more straight? d_labes 2012-03-08 08:29
            • and what about power? ElMaestro 2012-03-08 11:37
              • and what about power? d_labes 2012-03-08 13:26
              • and what about power?Helmut 2012-03-08 13:36
            • FDA more straight? Helmut 2012-03-08 12:51
              • FDA more straight? luvblooms 2012-03-09 06:55
                • Multiphasic MR ≠ DR Helmut 2012-03-09 12:18
                  • Multiphasic MR ≠ DR jag009 2012-03-28 15:29
                    • Metadate CD (30/70) Helmut 2012-03-28 15:45