Monocyte Activation Test (MAT)
for Radiopharmaceuticals.
Is endotoxin testing alone enough?
Passing a bacterial endotoxins test does not rule out non-endotoxin pyrogens. For your radiopharmaceutical development, this raises an important question: Is endotoxin testing alone adequately justified as your pyrogen control strategy?
Ph. Eur. 5.1.13 “Pyrogenicity” requires a risk-based justification when bacterial endotoxin testing is selected as the sole method for assessing pyrogenicity. The Monocyte Activation Test (MAT), described in Ph. Eur. 2.6.30, detects both endotoxin and non-endotoxin pyrogens and can provide important data to support your testing strategy.
CUP Contract Labs supports product-specific MAT planning for radiopharmaceuticals — from assessing feasibility under radioactive sample conditions to method adaptation and validation planning.
Endotoxins tested.
Pyrogen risk addressed?
What Ph. Eur. 5.1.13 means for your testing strategy.
Bacterial endotoxins are only one group of pyrogens. A passing endotoxin test result therefore does not establish whether non-endotoxin pyrogens are present.
This question should be addressed early, particularly for newly developed products. If the risk of non-endotoxin pyrogens cannot be adequately ruled out, endotoxin testing alone is not sufficiently justified. MAT enables broader pyrogen detection using human immune cells.
Together with a product-specific risk assessment, MAT results can support the decision on whether bacterial endotoxin testing alone is sufficient for routine quality control.
For radiopharmaceuticals, MAT suitability must be demonstrated under the intended sample conditions. Radioactivity, formulation and the timing of testing therefore need to be considered from the outset.
From Project Request
to MAT strategy.
Eight steps toward a robust MAT concept.
Our planned MAT workflow follows a clear, product-specific approach. The objective is not only to perform a test. The objective is a robust concept that is scientifically meaningful, operationally realistic, GMP-relevant in its documentation and suitable for regulatory discussion.
For radiopharmaceuticals, product matrix, radionuclide, activity level, sample volume, timing, radiation protection and validation objective must be considered at an early stage. This helps identify method-related risks before validation or regulatory discussions become time-critical.
You provide product information, development phase, intended test purpose and available sample details. This information forms the basis for the first technical assessment.
We review radionuclide, activity level, formulation, sample volume, matrix composition and timing. This creates a clear picture of the product-specific framework conditions.
We evaluate potential interferences, radiation-related requirements, dilution options and handling. The objective is a realistic assessment of whether MAT can be meaningfully implemented under the given conditions.
We develop a product-specific MAT concept including assay format, controls, sample preparation and acceptance criteria. The study design is aligned with the product, development phase and intended use of the results.
The MAT setup is adapted to the product matrix and radioactive sample workflow. Sample preparation, dilution strategy, controls and readout are specifically aligned with the product.
Interference, spike recovery, reproducibility and suitability are assessed according to the intended use. The validation scope may vary depending on the development phase and regulatory expectations.
Results are documented in a structured study report. This can support development, QA review and regulatory discussion.
Depending on project status, the method can support development studies, comparability work or future QC strategies. The objective is a MAT concept that is not only scientifically sound, but also practically implementable.
expert voices
For radiopharmaceuticals, it is not enough to ask whether a product can generally be tested. The key question is whether the test result remains scientifically meaningful under real radioactive sample constraints.
WHITEPAPER
Monocyte Activation Test for Radiopharmaceuticals.
Scientific background for your MAT strategy.
How can the Monocyte Activation Test be meaningfully transferred to radiopharmaceutical products? Our whitepaper explains the scientific background, regulatory requirements, typical feasibility questions and the structured CUP workflow for MAT projects under radioactive sample constraints.
Would you like to discuss a specific product or validation strategy directly? We can help you assess at an early stage which technical and regulatory questions are relevant for your MAT project.
Frequently asked questions
about MAT planning for radiopharmaceuticals.
Not automatically. The bacterial endotoxins test (BET) does not detect non-endotoxin pyrogens. Under Ph. Eur. 5.1.13, selecting BET as the sole method for assessing pyrogenicity requires a risk-based justification. Product-specific MAT data can help support this decision.
No. Testing during development and the subsequent routine testing strategy require separate consideration. The appropriate routine approach depends on the product-specific risk assessment, the available data and applicable regulatory requirements.
The dedicated MAT setup for radiopharmaceutical and complex injectable products is currently in preparation. Final regulatory notification is planned for August. Early technical discussions, project assessments and feasibility planning are already possible.
Radiopharmaceuticals can differ significantly from conventional parenteral products. Radionuclide, activity level, formulation, sample volume, decay profile and timing may influence cell viability, cytokine readout, dilution strategy and MAT interpretation.
We can already discuss product matrix, radioactive sample constraints, potential interferences, intended use, development phase, validation scope, sample logistics and documentation requirements. This helps define a realistic MAT strategy at an early stage.
At CUP, the focus is not only on performing a test. The key question is whether MAT can generate scientifically meaningful results under the real conditions of a radiopharmaceutical product. This is particularly relevant when validation, QA review or regulatory discussions need to be prepared.
Is BET enough for your product?
Find out early.
Product-specific MAT planning for radiopharmaceutical development.
Are you developing a radiopharmaceutical and looking to understand which MAT data could support your pyrogen testing strategy?
Discuss your product matrix, radionuclide and intended sample conditions with our team. Together, we can assess feasibility and define the next steps toward a product-specific MAT approach.
CUP supports you in the phase in which validation has not yet started, but the key decisions are being made:
- Is MAT suitable for your product?
- Which interferences can be expected?
- Which sample conditions are realistic?
- And how can a test concept be developed that can later be validated?
This creates an early MAT strategy for radiopharmaceutical and complex injectable products that is scientifically meaningful, operationally realistic and suitable for regulatory discussion.