Expert: Michael Anisfeld - 11/7/2007

Question
Is it accepted to retest the raw materials (API's/ inactives) when it's reach the "expiration date" , or it is just allowed for raw materials with "retesting date" ?? also what is the deference between "retesting date" and "expiration date"?
Please provide me with the official reference if possible.

Best regards

Answer
Under ICH-Q7 (GMPs for APIs) all APIs and by extension excipients) should have "retest dates". When the retest date is reached, the user has one of two options:

a. retest the material, and if it passes, use it wthin 30 days; or

b. start a long term stability study to extend the expiration date for say 1 year, or 2 years.

Much better is to order the API in smaller qantities and never get to the retest date.