Bioequivalence and Bioavailability Forum

Dear Torn
Due to gastro-intestinal complications you have to take isotretinoin with a meal. At time of clinical conduct of your study Guideline CPMP/QWP/EWP/1401/98 with the respective Q&A document EMEA/CHMP/EWP/40326/2006 was effective. In general, a bioequivalence study should be conducted under fasting conditions as this is considered to be the most sensitive condition to detect a potential difference between formulations (CPMP/QWP/EWP/1401/98 Rev. 1). This would also be the case for isotretinoin if this drug could be administered in the fasted state which is due to gastro-intestinal complications not possible. The SmPC does not contain any information about the composition of a meal to be taken with isotretinoin. The Q&A document points out that: “The composition of the meal should be described and taken into account, since a light meal might sometimes be preferable to mimic clinical conditions, especially when the fed state is expected to be less sensitive to differences in pharmacokinetics.”

I hope this helps
Kind regards
Dan