Bioequivalence and Bioavailability Forum

❝ is there any guidance which I can refer to in this point?

• It is acceptable to give a drug on the very last day of its shelf life to patients. Hence, the same is applicable in a BE study.
  
• Once the drug is in the circulation only the stability in matrix is relevant. The parent/metabolite(s) don’t “know” whats happening to the formulation. 
  
• For my analogy of expired reference standards see the FDA’s drafted BMV guidance Section III.B.1.a.
  That’s similar: If the stability of a stock solution is validated you can still use it, although the reference might have expired in the meantime.
  Logic behind: When you weighed the standard in, it was within its shelf life and therefore, the concentration of the stock solution correct. The drug in the stock solution doesn’t “care” that the standard expired.