You’re choosing excipients and determining amounts, so you go to the IAG (Inactive Ingredient Guide) look up the approved amounts and you’re good to go. Right?
Maybe not… You need to consider EXPOSURE. Exposure is amount over time. Look at the IAG and determine what products have this excipient/inactive ingredient and compute the potential exposure and compare this exposure to that of your excipient. If IAG is higher, great. If lower, you may have a problem. Do some digging – the IAG is not always up to date. If you cannot lower the proposed amount, check:
- recently approved products
- with your supplier for more recent data
- literature reviews to support higher amounts
Many people think that you’ll have to do tox studies. Not always. Camargo has been able to use literature in one case and data gathered during phase 1 or 2 in other cases.