Why the Monocyte Activation Test (MAT) is Now the Industry Standard
The pyrogen detection landscape is rapidly evolving. Effective July 1, 2025, the European Pharmacopoeia (Supplement 11.8) mandates the transition from the Rabbit Pyrogen Test (RPT) to a suitable in vitro method, such as the Monocyte Activation Test (MAT), for the detection of pyrogens in biologics and pharmaceuticals.
With 10+ years of MAT experience, we deliver scientifically-validated regulatory-ready results: reliably and ethically.
MAT offers significant advantages, including:
- Ethical: Completely eliminates animal use, aligning with the 3Rs principle (Replacement, Reduction, Refinement) and our focus on advancing alternatives to animal testing through our Alternative Methods Advancement Project™ (AMAP™).
- Scientifically accurate: MAT provides precise, accurate, and specific results based on the human-relevant reaction test methods.
- Regulatory compliance: Fully aligned with the latest European Pharmacopoeia pyrogenicity testing requirements (EP 2.6.8, 2.6.30, 5.1.10) and United States Pharmacopeia (USP <1225>, <151>) standards.
Pyrogenicity Testing Services
Monocyte Activation Test (MAT)
MAT is an advanced, animal-free pyrogenicity test method that uses cryopreserved human blood, PBMCs, or cell lines as a source of monocytes. The monocytes are incubated with endotoxin standards, controls, and test samples. If pyrogenic substances are present, monocytes release inflammatory cytokines like IL-1β or IL-6. These cytokines are then detected in a microtiter plate using specific antibodies and a colorimetric reaction with results expressed as endotoxin equivalent units/mL (EEU/mL).
MAT detects a broader range of pyrogens compared to traditional methods, including both endotoxins and non-endotoxin pyrogens, making it especially valuable for biologics and complex pharmaceuticals. Its human-relevant approach also enhances sensitivity and reliability for these advanced biotherapeutics.
Rabbit Pyrogen Test (RPT)
We continue to offer RPT to clients outside Europe, particularly those adhering to FDA guidelines. Within Europe, RPT is available when no suitable non-animal alternatives are available and approval has been granted by the European Medicines Agency (EMA).
The RPT detects pyrogens by injecting a sample of the biologic into rabbits and monitoring their temperature for several hours; a significant rise indicates pyrogens are present. All RPTs are performed using our own specific-pathogen-free (SPF) rabbits and in accordance with all pharmacopeia standards.
We also support clients considering transitioning to MAT for pyrogen testing; comparative validation studies and regulatory guidance are offered to help with future regulatory preparedness.
Endotoxin Testing
As part of our comprehensive pyrogen testing services, we offer in vitro bacterial endotoxin testing. All our assays are performed to meet all pharmacopoeia requirements, including gel-clot (qualitative) and turbidimetric kinetic and chromogenic (quantitative) methods. We also provide preliminary screening and validation of products as well as a backup technical service to clients.
Pyrogen Detection Application Suitability
| MAT | Rabbit Pyrogen Test | Endotoxin (LAL) | ||
|---|---|---|---|---|
| Principle of Test | ||||
| Fever Reaction Human | Fever Reaction Mammal | Defense Mechanism Arthropoda | ||
| Detectable Pyrogens | Gram-negative | + | + | + |
| Gram-positive | + | + | – | |
| Fungi | + | + | – | |
| Virus | + | +/– 1 | – | |
| Applications | Pharmaceuticals | + | + | + |
| Biologics | + | + | +/– 2 | |
| Blood components | + | – | – | |
| Cellular products | + | – | +/– | |
| Air pollutants | + | +3 | +/– 3 | |
| Medical devices | + | +3 | +/– 3 | |
| 1 Variable pyrogenic responses 2 Rabbit testing often required 3 Can only be tested indirectly by extracting device or filter with pyrogen-free water or saline | ||||
Supporting Your Transition to MAT
We understand that transitioning from RPT to MAT requires careful planning and product-specific validation. We actively support your transition by providing:
- Regulatory consultancy and guidance
- Comparative validation studies
- Training and education on MAT methodologies
Transitioning begins with ascertaining that MAT is a suitable test method for your product. This is done via interference factor testing, ensuring that the % recovery of a spiked product with a known concentration of endotoxin or non-endotoxin pyrogens is within regulatory standards (50-200%).
Pre-validation studies and product-specific validations follow, in accordance with EP or combined EP & ICH guidelines, depending on your target market.
Frequently Asked Questions (FAQs) About Pyrogenicity Testing
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What European regulation mandates the Monocyte Activation Test (MAT)?
The European Pharmacopoeia (Supplement 11.8) requires replacement of RPT with MAT, with a public deadline of June 30, 2025.
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Can we still request RPT testing?
Yes, RPT remains available for pyrogen testing in global markets outside Europe, notably North America. In Europe, MAT must be used unless specific exceptions apply and are approved by the EMA and local authorities.
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How long does MAT take compared to RPT?
MAT typically requires about two days and involves more hands-on work compared to the RPT or endotoxin testing methods.
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What should we consider when transitioning from RPT to MAT?
Transitioning involves product-specific validation. In some cases, the FDA may require Hold Time Studies (Low Endotoxin Recovery) to assess potential masking effects over time.
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Is MAT testing globally accepted?
MAT meets regulatory standards outlined by the European Pharmacopoeia (EP 2.6.8, EP 2.6.30, EP 5.1.10) and the US Pharmacopeia (USP <1225>, USP <151>). Other regions and countries are also moving toward MAT as an alternative to RPT.