USP <661> - Plastic Packaging Systems and Their Materials of Construction

What it says

General Chapter <661> describes physicochemical testing requirements for plastic materials and packaging systems used with pharmaceutical products, addressing both the base plastic materials themselves and the complete assembled packaging system, including extraction testing and spectroscopic identification methods.

Paraphrased for plain-language clarity. Always verify against the current published regulation text.

What it means in practice

• This chapter addresses plastic packaging specifically, complementing the elastomeric closure testing under USP <381> and providing the material-level and system-level qualification framework for the broader container-closure requirements described under 21 CFR 211.94.
• Testing at both the individual material and the complete assembled system level reflects that a packaging system's overall performance depends not just on individual component quality but on how those components function together as an integrated system.
• This chapter's requirements connect to biological reactivity testing under Chapters <87> and <88>, together forming a complete plastic packaging qualification framework addressing both physicochemical and biological compatibility.

What inspectors look for

• Whether plastic packaging qualification addresses both individual material characteristics and complete system performance, not just one or the other.
• Whether extraction testing results are connected to the broader extractables and leachables risk assessment for the specific product and packaging combination.
• Whether a packaging material or system change triggers the full scope of applicable requalification testing, not just a subset assumed sufficient.

Related regulations