Back to the Top
Dear All,
I'm actively working in a monkey pk/TK study of a recombination
humanized cytokine at very low dose level (daily subcutaneously dosed
at ~5ug/kg based on the potential clinical dosage). However, after the
first dose, all the serum samples had the concentration lower than the
LOQ (commerical ELISA kit, 7pg/mL). Directly observed by the OD
values, we believed that the Cmax should be 1~2 hrs postdose. From the
published article, which dosed at 10 times higher dosage, the T1/2
should be ~3 hrs.
The question is, for IND submission, must I develop a more sensitive
analytical method? (I'm going to try some electrochemical detection,
which might had the LOQ approximate about 1 pg/g. but I also doubt if
this was sensitive enough, if the Cmax was 7 pg/mL, we need a LOQ at
least 0.7pg/mL as the guidance) . Radio-lable is the last choice,
considering the further clinical trial.
Can anybody give me more suggestion from the regulatory view? can we
dose at 20 times higher level and submiss the data? Higher level will
meet the linear or nonlinear problem, but extraploation of the lower
level will not? right?
Thanks a lot
Ning
Want to post a follow-up message on this topic?
If this link does not work with your browser send a follow-up message to PharmPK@boomer.org with "Recombination humanized cytokine assay" as the subject | Support PharmPK by using the |
Copyright 1995-2011 David W. A. Bourne (david@boomer.org)