I have received two or three queries on this topic in recent weeks. I am providing the response with a web-post so that others may benefit from my response as well. The current query is as follows (the name has been deleted and data has been blacked out to keep it confidential):
Qurey:
I read your many excellent articles which guide well the peoples who are new in drug delivery.
After reading a lot of literature on IVIVC, there is still a query in my mind as asked below:
Plasma drug level can be predicted from in vitro dissolution data by two ways:
1. Using convolution approach
2. Using IVIVC
I know how to predict plasma drug level using convolution approach but don’t know how to calculate from IVIVC.
In this context, I need your guidance.
Suppose I have established Level A IVIVC for a tablet formulation with following outcomes; Y = x.xxxX – x.xxx, R2 = 0.xxx.
Then I changed an excipient and did the dissolution testing for new tablet. The new dissolution data is attached. Its outcomes are as; Y = x.xxxX – x.xxx, R2 = 0.xxx.
Now, how can I predict plasma drug level for this new tablets using previously established IVIVC.
Thanking you in advance and regards
Response:
Please, note that plasma drug levels can only be predicted/estimated using the convolution method. IVIVC cannot be used to predict plasma drug levels. I realize that there has been significant promotion to this effect, but unfortunately it is not correct. Furthermore, IVIVC is also of limited, or of no use, during the product development stage, where prediction/estimation of plasma levels is required and the convolution method is the only option for obtaining the required results.
For further information on this topic the following articles may be of help.
http://www.drug-dissolution-testing.com/?p=1648
http://www.drug-dissolution-testing.com/?p=1643
http://www.drug-dissolution-testing.com/?p=833
