ICH Q6 Explained: Specifications, Control Strategy, and What’s Changing in Q6(R1)

In this episode of Let’s ComBinate, Subhi continues the ICH Q-series with ICH Q6 and explains why specifications are central to defining and controlling drug products and drug-device combination products.

He breaks down how ICH Q6 formalizes:

• what to test (attributes or CQAs tied to safety and efficacy)

• how to test (methods and procedures)

• what is acceptable (acceptance criteria or limits)

All of which come together to support the release decision.

He also covers the difference between ICH Q6A (small molecules) and ICH Q6B (biologics), highlighting the increased variability in biologics and the greater reliance on characterization and process understanding.

Finally, he summarizes key themes from the 2024 ICH Q6(R1) concept paper, including:

• alignment of shared principles across Q6A and Q6B

• expanded scope to include new modalities and combination products

• linkage to ICH Q12 lifecycle management and established conditions

• a shift toward more science and risk based approaches with less reliance on routine batch testing

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Key References

• ICH Q6 Guidelines (Q6A and Q6B):

https://www.ich.org/page/quality-guidelines

• ICH Q6(R1) Concept Paper (2024):

https://www.ich.org/page/quality-guidelines (navigate to Q6 revision concept paper)

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Timestamps

00:00 Intro to ICH Q6

00:36 Host background

01:05 Why specifications matter

01:49 Q6A vs Q6B overview

02:33 Purpose of ICH Q6

02:59 What is a specification

04:27 Q6 R1 update themes

05:49 Lifecycle and risk based specifications

06:29 Wrap up and next steps

Subhi Saadeh is the Founder and Principal at Let’s Combinate, where he helps teams develop and control drug-device combination products by aligning quality systems, development, and regulatory expectations across drug and device domains.