Introduction
GMP Extractables and Leachables Testing is a systematic approach to identifying, characterizing, and evaluating chemical substances that may migrate from product-contact materials into pharmaceutical formulations. It becomes mandatory in practice when the results support a regulatory filing, product release, stability claim, or patient-safety decision.
Pharmaceutical products contact many materials during manufacturing, storage, packaging, and administration, including glass containers, polymer bottles, rubber stoppers, plastic tubing, filters, elastomeric components, syringes, and single-use manufacturing systems. These components are designed to protect the product, yet they can release chemicals that compromise quality and patient safety.
Extractables and leachables are closely related but represent different stages of chemical migration. For pharmaceutical companies, CDMOs, and biotechnology manufacturers, understanding the distinction is essential for selecting materials, setting specifications, and demonstrating regulatory readiness.
At ResolveMass Laboratories Inc., a Canadian analytical CRO/CDMO, our analytical characterization and pharmaceutical testing capabilities support the scientific evaluation of complex materials and potential chemical impurities. A well-designed E&L strategy generates reliable analytical evidence for product development and quality decisions.
Summary:
- Extractables are compounds that can be released from packaging, manufacturing equipment, or product-contact materials under exaggerated laboratory conditions.
- Leachables are compounds that actually migrate into the drug product during manufacturing, storage, or administration.
- GMP-grade E&L testing becomes critical when product-contact materials can introduce chemical contaminants that may affect patient safety, product quality, stability, or regulatory compliance.
- USP <1663> provides guidance on extractables assessment, while USP <1664> addresses leachables assessment.
- ICH Q3E (still draft guidance) provides a developing framework for assessing extractables and leachables.
- Risk-based testing considers material composition, dosage form, route of administration, exposure duration, formulation, and patient population.
- Analytical techniques such as GC-MS, LC-MS/MS, ICP-MS, and high-resolution mass spectrometry identify and quantify organic and inorganic leachables.
- A comprehensive E&L program supports development, GMP manufacturing, regulatory submissions, and lifecycle management.
- Start early. Establish a scientifically justified E&L strategy during development, not at commercial manufacturing or submission.
1. What Are Extractables and Leachables in Pharmaceutical Manufacturing?
Extractables and leachables are chemical substances that originate from packaging, manufacturing equipment, or delivery materials and may enter a pharmaceutical product. They differ in the conditions under which they are released and detected.
What Are Extractables?
Extractables are compounds released from a material under aggressive laboratory conditions, such as elevated temperature, extreme pH, or strong organic solvents. These studies reveal the potential chemical composition of substances that could migrate from product-contact materials.
Common sources include:
- Plastic containers and polymer packaging
- Rubber stoppers and elastomeric seals
- Plastic tubing and transfer lines
- Filters and filtration membranes
- Single-use bioprocessing bags
- Adhesives, coatings, and lubricants
- Pharmaceutical manufacturing equipment
Typical extractable compounds include antioxidants, plasticizers, monomers, oligomers, residual solvents, processing aids, and elemental impurities.
What Are Leachables?
Leachables are compounds that migrate into the actual drug product under normal or simulated conditions of manufacturing, storage, and administration. They are evaluated under conditions designed to represent real-life exposure.
Examples include:
- Plasticizers migrating from polymer containers into liquid formulations
- Rubber stopper additives entering injectable products
- Silicone-related compounds migrating into biologic formulations
- Antioxidants and degradation products released from plastic packaging
- Metal ions from product-contact manufacturing components
Leachables matter most because their presence in the final product can affect patient safety, stability, efficacy, and quality.
2. Extractables vs. Leachables: Key Differences
Extractables represent the potential chemical release from a material, whereas leachables are the compounds that actually migrate into a drug product under relevant conditions.
| Parameter | Extractables | Leachables |
|---|---|---|
| Definition | Compounds released under controlled extraction conditions | Compounds migrating into the drug product |
| Testing conditions | Exaggerated or aggressive | Actual or simulated use conditions |
| Primary objective | Identify potential chemical contaminants | Determine actual product exposure |
| Testing material | Packaging or product-contact components | Drug product or representative formulation |
| Conditions | Elevated temperature, solvents, controlled pH | Intended storage and manufacturing conditions |
| Timing | Development and material qualification | Development and stability studies |
| Analytical purpose | Establish an extractables profile | Identify and quantify product-related leachables |
| Risk assessment | Potential migration and hazard identification | Patient exposure and toxicological evaluation |
Important: An extractable is not automatically a leachable. A substance found in an aggressive extraction may never migrate into the drug product under normal conditions. Extractables data does, however, help predict and investigate potential leachables.
3. When Does GMP Extractables and Leachables Testing Become Mandatory?
GMP Extractables and Leachables Testing becomes necessary when risk assessments, applicable regulatory requirements, or product-specific circumstances indicate that chemicals migrating from product-contact materials could affect drug product safety, quality, or purity.
No universal rule requires the same E&L package for every product. Manufacturers must instead demonstrate that their packaging and manufacturing materials are suitable for their intended use. Data that supports a filing, release decision, or stability claim should be generated in a GMP-compliant environment, following a GMP-compliant extractables and leachables (E&L) study design.
3.1 Injectable and Parenteral Drug Products
Injectables generally require a more stringent assessment because contaminants can enter the bloodstream or tissues without passing through the gastrointestinal tract.
Materials to consider:
- Rubber stoppers and vial seals
- Prefilled syringe components
- Glass vials and polymer containers
- Injectable product tubing
- Sterile filtration membranes
- IV administration sets
For example, an injectable stored in a polymer container may be exposed to plasticizers, antioxidants, or other additives over its shelf life. GMP-grade E&L testing determines whether these compounds migrate and whether their concentrations raise a safety concern.
3.2 Biologics and Monoclonal Antibody Formulations
Biological products are especially sensitive to interactions with packaging and manufacturing materials. Even low concentrations of certain leachables may influence protein stability or aggregation.
Potential sources:
- Single-use bioprocessing systems
- Bioreactor bags and connectors
- Silicone-coated syringes
- Polymer storage containers
- Tubing and filtration assemblies
Silicone-related compounds or other organic contaminants may contribute to particle formation or aggregation. E&L studies for biologics should therefore be integrated with stability studies, formulation compatibility assessments, and product quality investigations.
3.3 Single-Use Manufacturing Systems
Single-use technologies reduce cleaning requirements and cross-contamination risk, but disposable components can introduce extractables and leachables into process intermediates or finished products. Learn more about single-use systems and GMP E&L testing.
Common examples:
- Bioprocessing bags
- Tubing assemblies
- Connectors and fittings
- Sterile filters
- Disposable mixing systems
- Sampling components
Manufacturers should evaluate these materials and decide whether supplier extractables data adequately covers their actual process conditions.
3.4 Long-Term Storage and Drug Delivery Systems
Products with long shelf lives or prolonged polymer contact need chemical compatibility assessments. Examples include long-acting injectables, implantable delivery systems, ophthalmic solutions, inhalation products, prefilled syringes, and transdermal systems. The longer a product contacts a material, the greater the opportunity for migration, depending on formulation and material properties.
3.5 Clinical to Commercial Scale-Up
Changes in scale, suppliers, or packaging configuration between clinical and commercial manufacturing can alter the chemical profile. Planning E&L testing for clinical to commercial scale-up helps avoid repeat studies and late-stage surprises.
Quick Reference: Is GMP Compliance Required?
| Scenario | GMP-grade testing expected? |
|---|---|
| Leachables data in an IND, NDA, ANDA, BLA, or MAA | Yes |
| Leachables monitoring on registration or commercial stability batches | Yes |
| Data used to release product or justify a specification | Yes |
| Change in packaging material, supplier, or sterilization method | Usually, after a documented risk assessment |
| Early packaging screening and feasibility work | Not necessarily |
| Method development before validation | Not necessarily |
4. Regulatory Guidelines Governing GMP Extractables and Leachables Testing
Regulators expect proof that packaging and product-contact materials do not compromise the safety, quality, or purity of a drug product. Several regulatory and pharmacopeial references guide this work.
4.1 USP <1663>: Assessment of Extractables
USP <1663> provides a scientific framework for designing and conducting extractables assessments for packaging and delivery systems. It addresses:
- Selection of extraction conditions
- Identification of potential extractables
- Analytical evaluation of extracted compounds
- Material characterization
- Interpretation of extractables profiles
- Application of extractables data to risk assessments
USP <1663> is an informational general chapter. It does not prescribe universal extraction conditions or mandatory acceptance limits for every packaging system.
4.2 USP <1664>: Assessment of Drug Product Leachables
USP <1664> guides the evaluation of leachables associated with packaging and delivery systems. It focuses on which compounds migrate into the drug product and their potential impact on patient safety and quality. Key considerations:
- Identification of potential leachables
- Drug product compatibility
- Analytical method selection
- Stability-related migration
- Toxicological evaluation
- Control strategies for identified leachables
Like <1663>, it supports scientifically justified assessments rather than a single testing protocol.
4.3 ICH Q3E: Extractables and Leachables
ICH Q3E is a developing international framework for assessing and controlling E&L in pharmaceutical products. The draft guideline, published in August 2025, takes a holistic, risk-based approach that complements existing impurity guidelines:
- ICH Q3A: Impurities in New Drug Substances
- ICH Q3B: Impurities in New Drug Products
- ICH Q3C: Residual Solvents
- ICH Q3D: Elemental Impurities
- ICH M7: DNA-Reactive (Mutagenic) Impurities
Public consultation closed in December 2025, and the EMA published an overview of comments in January 2026, updated in April 2026. As of November 2026, Q3E should be treated as draft guidance until a final version is adopted. Manufacturers should not treat draft recommendations as binding requirements.
4.4 FDA Requirements for Container Closure Systems
FDA emphasizes that packaging components must not adversely affect the safety, identity, strength, quality, or purity of drug products. Under 21 CFR 211.94, containers and closures must be suitable for their intended use and protect against contamination and deterioration.
FDA’s August 2026 draft guidance, Container Closure Systems for Human Drugs and Biological Products, offers updated recommendations. It is draft guidance and is not legally binding.
Regulatory Snapshot
| Reference | Scope | Status |
|---|---|---|
| USP <1663> | Extractables assessment | Informational general chapter |
| USP <1664> | Leachables assessment | Informational general chapter |
| ICH Q3E | E&L risk-based framework | Draft guidance |
| 21 CFR 211.94 | Container and closure suitability | Binding regulation |
| FDA container closure guidance | Container closure evaluation | Draft guidance, not legally binding |
5. How Is GMP Extractables and Leachables Testing Performed?
GMP Extractables and Leachables Testing follows a structured workflow: material assessment, extraction studies, analytical characterization, leachables evaluation, and toxicological risk assessment.
Step 1: Material Risk Assessment
Identify all materials with direct or indirect product contact. Consider material composition, manufacturing process, contact duration, storage conditions, formulation, route of administration, and potential patient exposure. This determines which materials need further investigation.
Step 2: Extractables Study
Selected solvents and controlled conditions reveal compounds that may be released. Conditions reflect the material, intended application, and worst-case exposure. Common approaches:
- Polar solvent extraction
- Non-polar solvent extraction
- Aqueous extraction
- Elevated-temperature extraction
- Controlled pH extraction
The goal is a comprehensive extractables profile without introducing analytical artifacts or degrading the material in ways unrelated to its intended use.
Step 3: Analytical Characterization
| Analytical technique | Primary application |
|---|---|
| GC-MS | Volatile and semi-volatile organic compounds |
| GC-HRMS | High-resolution characterization of volatile and semi-volatile compounds |
| LC-MS/MS | Targeted identification and quantification of organic compounds |
| LC-HRMS | Non-volatile and thermally labile organic compounds |
| ICP-MS | Elemental and inorganic impurities |
| FTIR | Material identification and polymer characterization |
| NMR | Structural elucidation of selected unknown compounds |
Combining complementary techniques gives broader chemical coverage than any single platform.
Step 4: Leachables Study
Leachables studies evaluate migration into the actual formulation, or a scientifically justified representative product, at multiple time points under relevant storage conditions. Important parameters:
- Temperature and storage duration
- Formulation pH and solvent composition
- Container contact surface area
- Product concentration
- Light exposure, where relevant
A liquid injectable in a polymer container, for example, may be evaluated during accelerated and long-term stability studies.
Step 5: Identification and Quantification
Detected compounds are identified using reference standards, mass spectral libraries, accurate-mass data, fragmentation patterns, and other supporting evidence. Quantification may use:
- Authentic reference standards
- Compound-specific calibration
- Appropriate surrogate standards where justified
- Semi-quantitative approaches when authentic standards are unavailable
Unknown compounds should be assigned identification confidence levels, and analytical uncertainty should be considered during interpretation.
Step 6: Toxicological Risk Assessment
The final step evaluates whether identified leachables pose an unacceptable patient risk. The assessment considers chemical identity, daily exposure, route of administration, treatment duration, toxicological data, mutagenicity or other hazard characteristics, and applicable safety thresholds. Additional toxicological testing or expert evaluation may be needed before control limits are set.
Documentation and Data Integrity
GMP status depends on traceable records as much as on the science. Procedures, raw data, deviations, investigations, and final assessments must be documented and reviewed. See our guidance on GMP data integrity for extractables and leachables testing.
6. What Are the Critical Analytical Challenges in E&L Testing?
The major challenges are identifying unknown compounds, detecting trace-level contaminants, separating genuine leachables from analytical artifacts, and establishing scientifically justified safety limits.
6.1 Identification of Unknown Compounds
Unknown compounds may come from polymer degradation, additives, adhesives, or processing residues. High-resolution mass spectrometry (HRMS) supports accurate-mass measurement and structural characterization.
6.2 Trace-Level Detection
Some concerning leachables occur at very low concentrations. Methods must demonstrate suitable sensitivity, selectivity, precision, and accuracy for the intended assessment.
6.3 Matrix Interference
Excipients, proteins, buffers, and other components, particularly in biologics and injectables, can interfere with measurements. Proper sample preparation, chromatographic separation, and matrix-specific method validation minimize this.
6.4 Establishing Analytical Evaluation Thresholds (AET)
The AET is the level above which an extractable or leachable should be identified and evaluated. Calculations consider:
- Relevant toxicological safety thresholds
- Maximum daily product exposure
- Product-specific concentration and dosing
- Analytical uncertainty and response-factor considerations
An AET is not a universal toxicological acceptance limit or a generic instrument detection limit. It is an analytical decision threshold that guides chemical characterization.
7. What Are the Risks of Inadequate GMP Extractables and Leachables Testing?
Inadequate E&L assessment can cause product quality issues, patient safety concerns, regulatory questions, and commercial delays.
| Risk | Potential impact |
|---|---|
| Undetected chemical contaminants | Patient exposure to harmful substances |
| Packaging incompatibility | Changes in drug product quality |
| Protein aggregation | Reduced biologic stability |
| Unknown leachables | Additional regulatory investigations |
| Inadequate material qualification | Delays in manufacturing approval |
| Insufficient analytical documentation | Regulatory review deficiencies |
| Uncontrolled material changes | Increased lifecycle quality risk |
If a rubber stopper releases an additive into an injectable, the contaminant can stay undetected without proper characterization. Likewise, leachables from single-use components may affect biologic intermediates. An effective program surfaces these risks before they become manufacturing or regulatory problems.
8. How Can Manufacturers Establish an Effective GMP E&L Strategy?
An effective strategy integrates material qualification, analytical testing, toxicological evaluation, and lifecycle management into the pharmaceutical quality system.
- Conduct early material risk assessments. Evaluate materials during development, not at commercial production.
- Obtain supplier documentation. Request composition, extractables profiles, processing details, and compliance documents.
- Select appropriate analytical methods. Use complementary techniques (GC-MS, LC-MS/MS, HRMS, ICP-MS) matched to the expected chemical profile.
- Establish justified acceptance criteria. Evaluate compounds against toxicological and regulatory considerations.
- Integrate E&L with stability studies. Monitor potential leachables across relevant storage periods.
- Maintain GMP documentation. Keep procedures, raw data, deviations, investigations, and assessments reviewed and traceable.
- Reassess after material changes. New suppliers, polymer formulations, processes, sterilization conditions, or packaging configurations may require updated risk assessment and testing.
- Qualify your partners. Apply rigorous CDMO qualification and audit practices to any laboratory or manufacturer generating GMP data on your behalf.
9. How ResolveMass Laboratories Inc. Supports Pharmaceutical E&L Analytical Requirements
Reliable E&L assessment requires more than detecting compounds. It needs sound method selection, compound identification, quantitative evaluation, and scientifically supported interpretation.
ResolveMass Laboratories Inc. supports pharmaceutical and biotechnology organizations with specialized analytical testing and characterization relevant to complex impurity investigations and material evaluation.
| Analytical capability | Relevance to E&L assessment |
|---|---|
| GC-MS | Volatile and semi-volatile organic compounds |
| GC-HRMS | High-resolution characterization of unknown organic compounds |
| LC-MS/MS | Sensitive targeted quantification of selected leachables |
| LC-HRMS | Non-volatile and unknown organic compounds |
| ICP-MS | Elemental impurity and metal analysis |
| NMR | Structural elucidation of unknown substances |
| FTIR | Material identification and functional group characterization |
Potential areas of support include:
- Identification and characterization of organic impurities
- Targeted analytical investigations
- Trace-level impurity quantification
- Elemental impurity analysis
- Structural characterization of unknown compounds
- Analytical method development and validation
- Pharmaceutical product and material characterization
For GMP-compliant E&L study projects, the analytical scope should be set through a product-specific assessment. Instrument availability alone does not mean a complete E&L study, including toxicological assessment and regulatory acceptance, is covered.
Conclusion:
Extractables identify compounds that could migrate from product-contact materials, while leachables studies establish which substances actually enter the drug product under real or simulated conditions. GMP Extractables and Leachables Testing becomes essential when packaging, manufacturing components, or delivery systems present a potential risk to patient safety or product quality.
USP <1663>, USP <1664>, FDA container closure requirements, and the developing ICH Q3E framework provide scientific and regulatory direction. The most effective approach is to integrate E&L testing early, choose suitable analytical techniques, set justified safety thresholds, and maintain GMP documentation across the product lifecycle.
Frequently Asked Questions:
Inadequate E&L testing may result in undetected chemical contamination, packaging incompatibility, product degradation, protein aggregation, patient exposure to potentially harmful compounds, and regulatory deficiencies. It may also delay pharmaceutical product development and commercial approval.
ICH Q3E provides an international framework for evaluating and controlling extractables and leachables in pharmaceutical products. It promotes a risk-based approach to chemical characterization, analytical evaluation, and toxicological assessment. Its regulatory status should be checked before applying draft recommendations as requirements.
Pharmaceutical companies can reduce E&L risks by:
– Selecting suitable pharmaceutical-grade packaging materials.
– Evaluating supplier extractables documentation.
– Conducting material compatibility assessments.
– Performing risk-based E&L studies.
– Monitoring leachables during stability testing.
– Establishing appropriate analytical control strategies.
– Reassessing materials after significant manufacturing changes.
Single-use bioprocessing systems require an appropriate risk-based E&L assessment because polymer bags, tubing, filters, and connectors may release chemical substances into process fluids. The extent of testing depends on process conditions, material characteristics, contact duration, and potential impact on the final drug product.
Reference
- Samaras JJ, Micheletti M, Ding W. Transformation of biopharmaceutical manufacturing through single-use technologies: current state, remaining challenges, and future development. Annual Review of Chemical and Biomolecular Engineering. 2022 Jun 7;13(1):73-97.https://www.annualreviews.org/content/journals/10.1146/annurev-chembioeng-092220-030223
- Jossen V, van den Bos C, Eibl R, Eibl D. Manufacturing human mesenchymal stem cells at clinical scale: process and regulatory challenges. Applied microbiology and biotechnology. 2018 May;102(9):3981-94.https://link.springer.com/article/10.1007/s00253-018-8912-x
- Ball O, Zylberberg C. Towards a common framework for defining ancillary material quality across the development spectrum. Cytotherapy. 2019 Dec 1;21(12):1234-45.https://www.sciencedirect.com/science/article/pii/S1465324919308680
- Solomon J, Csontos L, Clarke D, Bonyhadi M, Zylberberg C, McNiece I, Kurtzberg J, Bell R, Deans R. Current perspectives on the use of ancillary materials for the manufacture of cellular therapies. Cytotherapy. 2016 Jan 1;18(1):1-2.https://www.sciencedirect.com/science/article/pii/S1465324915010671
- Minas W. Transforming a R&D-oriented start-up into a GMP-compliant biopharmaceutical production. Pharm. Ind. 2018;80(4,482-492):201s.https://www.researchgate.net/profile/Wolfgang-Minas/publication/324981919_Transforming_a_RD-oriented_start-up_into_a_GMP-compliant_biopharmaceutical_production_organization/links/62e7dc4a9d410c5ff37af9a6/Transforming-a-R-D-oriented-start-up-into-a-GMP-compliant-biopharmaceutical-production-organization.pdf
- Detela G, Lodge A. Manufacturing process development of ATMPs within a regulatory framework for EU clinical trial & marketing authorisation applications. Cell Gene Ther. Insights. 2016;2(4):425-52.https://cdn.insights.bio/uploads/attachments/Lodge%20&%20Detela.pdf
About the Author
