Understanding the Tip:
What are leachables and migratables?
Leachables are substances that migrate into a drug product from its container or closure system during storage, while migratables refer more broadly to all substances that can be transferred from the packaging under real use or storage conditions. These substances may arise from inks, adhesives, rubber stoppers, or plasticizers and can compromise product quality, safety, and efficacy. Including their evaluation in stability programs is essential to ensure compatibility over the product’s shelf life.
Why this matters for pharmaceutical safety:
Without leachable and migratable testing:
- Undetected substances may pose toxicity risks
- Regulatory submissions may be rejected or delayed
- Unexpected impurities could exceed ICH Q3B limits
- Stability failures may be linked to packaging instead of formulation
Proactively assessing leachables protects patients and strengthens your product’s regulatory acceptance.
Regulatory and Technical Context:
ICH and WHO recommendations on container-closure compatibility:
ICH Q3B emphasizes the need to monitor degradation products, including those that may result from packaging interaction. WHO TRS 1010 and FDA guidance stress that the container-closure system should not affect product safety or efficacy throughout the shelf life. CTD Modules 3.2.P.2 and 3.2.P.7 must describe material compatibility, while Module 3.2.P.8.3 should summarize testing outcomes, including any leachable-related concerns.
Audit expectations and global regulatory standards:
Inspectors typically review:
- Leachables and extractables
Absence of these evaluations may result in data deficiencies, additional testing mandates, or shelf-life re-evaluation.
Best Practices and Implementation:
Begin with extractables testing and risk prioritization:
Start by:
- Conducting extractables studies under exaggerated conditions
- Identifying compounds using GC-MS, LC-MS, and ICP-MS
- Creating a leachables target list for routine monitoring
Prioritize risk based on dosage form (e.g., higher risk for injectables or inhalation products).
Perform leachables testing at real-time and accelerated intervals:
Include leachables testing:
- At initial (0M), intermediate (6M), and final (12M/24M) stability time points
- For all intended storage conditions (long-term, accelerated)
- On samples stored in final commercial packaging
Use validated analytical methods sensitive enough to detect trace levels of known or unknown leachables.
Document all findings and link to product safety profile:
Ensure:
- Toxicological thresholds (e.g., PDEs) are compared against observed levels
- Reports are reviewed and approved by QA and toxicology teams
- Results are archived and summarized in regulatory dossiers
Link findings to formulation and packaging development reports to demonstrate comprehensive risk control.
Integrating leachable and migratable testing into your stability study framework is vital for long-term product safety and global regulatory approval. It reflects a mature quality system and a science-driven approach to pharmaceutical risk management.