Primidone BE study for USFDA submission [Regulatives / Guidelines]
Couldn't find any approval packages on Drugs@FDA, so I'm going to have to use science rather than precedent, shucks.
PEMA and PHB are both active metabolites, but based on the FDA general guidance, I am not sure that triggers a requirement to test for them.
However, the guidance specifically recommends PK samples for metabolites when there may be gut/enteric metabolism. Primidone undergoes autoinduction so it is likely metabolized by 3A4, which is in the gut. I suppose this is a trigger for metabolite monitoring?
Another point about autoinduction, is there are persistent effects on metabolism. A long washout period, determined by turnover number of CYPs should be applied. I am not sure what you guys do in practice. PHB can hang with the best of them (like rifampin) in terms of induction.
PEMA and PHB are both active metabolites, but based on the FDA general guidance, I am not sure that triggers a requirement to test for them.
However, the guidance specifically recommends PK samples for metabolites when there may be gut/enteric metabolism. Primidone undergoes autoinduction so it is likely metabolized by 3A4, which is in the gut. I suppose this is a trigger for metabolite monitoring?
Another point about autoinduction, is there are persistent effects on metabolism. A long washout period, determined by turnover number of CYPs should be applied. I am not sure what you guys do in practice. PHB can hang with the best of them (like rifampin) in terms of induction.
Complete thread:
- Primidone BE study for USFDA submission Ramesh Ramalingam 2018-04-09 05:54 [Regulatives / Guidelines]
- Primidone BE study for USFDA submission jag009 2018-04-09 16:16
- Primidone BE study for USFDA submissionbebac_fan 2018-04-10 01:11
- Primidone BE study for USFDA submission Ramesh Ramalingam 2018-04-11 06:07
- Primidone BE study for USFDA submission Ramesh Ramalingam 2018-04-11 06:05
- Primidone BE study for USFDA submissionbebac_fan 2018-04-10 01:11
- Primidone BE study for USFDA submission balakotu 2018-04-12 15:01
- Primidone BE study for USFDA submission jag009 2018-04-09 16:16