Bioequivalence and Bioavailability Forum

Dear Ratnakar!

❝ ❝ I’m always suggesting to use actual sampling times

❝                                 ^^^^^^^^^^^^^^^^^^^^^^^

❝ […] recently i have received a letter from WHO for using actual time for PK analysis

Not surprising; see WHO Technical Report Series, No. 937 (2006)
Annex 7:

6.10 Reporting of Results
The tabulated results should present the date of run, subject, study period, product administered (multisource or comparator) and time elapsed between drug application and blood sampling in a clear format.

Annex 9:

19.3 Actual sampling times and deviations from the pre-specified sampling times should be recorded.

❝ […] as earlier we were cinsidering schedule time if the deviation is

❝ <10% and for deviation >10% actual time.

Since you are already able to perform the calculation on actual times (according to your procedure if deviation >10%), why not to employ it in all cases?

❝ Generally we have a window of 2 min for inhouse sampling and for ambulatory samples we have a window of 1 hr mentioed in the protocol, now my question is should we use actual time for all the deviation irrespective as mentioned above (i.e. even the sample is delayed by 1 min also) or for only those samples for which protocol deviation required to be filed?

If ever possible use the actual sampling time in the calculation. Many CROs record all actual times, and define time windows in the protocol where deviations have to be commented in the CRF.

❝ Currently we have mentioned actual time to be considered for all the deviations even it is for 1 min also.

Hhm, isn’t that a contradiction?