The ICH Q11 Expert Working Group (EWG) has been wrestling with balancing regulatory transparency with industry flexibility in defining the starting material as it moves forward in drafting the guideline on drug substance development and manufacturing.
Reporting on the discussions that took place the previous week at the EWG’s meeting in Tallinn, Estonia, Q11 rapporteur Brian Withers (Abbott, U.K.) pointed out at DIA’s Annual Meeting in Washington, D.C. in mid-June that the starting material guidance was among the challenges drawing his group’s attention.
With the application of the Q7 drug substance GMPs at issue, Withers explained, the later the starting material is designated in the process, “the more flexibility there is for industry [but] the less visibility there is to the regulator, either in a submission or via review of the quality system. So the challenge for the expert working group has been how to get that balance between transparency and flexibility in terms of the two approaches.”
Industry has also had to think about this balance in terms of how much value to place on predictability. If industry wanted predictability, the guidance could have been written easily to delineate the starting material as a specific number of steps, say five or six, from the last step in the synthesis, Withers stressed.
“That would have been, I think, acceptable to all the agencies, and it would have given predictability to industry. But it wouldn’t necessarily give the flexibility for industry to propose alternatives when it is linked to the overall control strategy for the drug substance. That has proved difficult – again, how to build in a risk-based approach to the designation of the starting material.”
[Withers’ update on how the EWG is proceeding to resolve the issues around starting materials is provided for subscribers here. See the companion story in IPQ’s “In the News” to learn more about the discussions at the Tallinn EWG meeting on the structure and content of the ICH Q11 guideline.]