In response to stakeholders’ concerns, the General Chapters – Packaging and Distribution Expert Committee introduced two revisions earlier this year to United States Pharmacopeia (USP) 661.2 Plastic Packaging Systems for Pharmaceutical Use, which provides test methods and standards for plastic packaging systems.
The comment period regarding the proposed updates ended May 31, 2023, and the committee will vote whether or not to move forward with these two changes in the upcoming weeks.
1. Lowering extraction time and temperature.
Desmond Hunt, scientific liaison to the general chapters, explains that one of the proposed revisions addresses the concern that the lowest extraction temperature in the chapter could lead to melting of the packaging system. The update would include another extraction temperature that will allow testing for packaging materials that melt at 70 degrees.
The change in the chapter would be as follows:
Heat in an autoclave until 121 ± 2° is reached (typically in 20–30 minutes) and maintain at this temperature for 30 minutes. If heating at 121° leads to the deterioration of the container, heat at 100 ± 2° in an autoclave or oven. If heating at 100° leads to the deterioration of the container, heat at 70 ± 2° for 24 hours in an autoclave or oven. If heating at 70° leads to the deterioration of the container, heat at 50 ± 2° for 72 hours.
2. Aligning total organic carbon acceptance criteria.
When the chapter was initially developed, the specifications for total organic carbon (TOC) were the same as chapter 643; however, last year the expert committee changed them. Hunt shares that stakeholders reached out to the committee asking them to keep the specifications that were in USP general chapter 643 to make sure they stayed aligned.
The second revision to the chapter would be as follows:
The difference in TOC concentrations between Solution C1 and a suitable blank is NMT 32 milligrams per liter for containers ≤ 5 milliliters; NMT 24 mg/L for containers > 5 and ≤ 100 mL; and NMT 8 mg/L for containers > 100 mL.
Steps in the right direction.
Hunt sees the proposed revisions as positive: “We added an additional extraction temperature, so now those companies who were struggling to test their materials should be fine,” he says. “And aligning the TOC specifications with 643 is a positive direction for industry because you would want limits to apply across the board and not just for one chapter versus another.”
According to Hunt, the revision process for the plastic packaging chapter has been underway since its initial development several years ago. The official implementation date of USP 661.2 is December 1, 2025.
“I hope companies have this on their radar and — depending on how big their portfolio is — they’re looking to make sure the materials they have comply,” says Hunt.
Kassandra Kania is a freelance writer based in Charlotte, NC. She has written extensively about healthcare packaging for a variety of publications.