IVDR Explained: In Vitro Diagnostic Classification, Performance Evaluation and Transition Deadlines

The In Vitro Diagnostic Regulation (EU) 2017/746, known as the IVDR, replaced the old In Vitro Diagnostic Directive and changed the market for diagnostic manufacturers far more than the MDR changed it for device makers. Under the old directive, most IVDs were self-declared. Under the IVDR, most need a notified body. This guide explains how the IVDR classifies devices, how the conformity routes work, what performance evaluation involves, and how the extended transition deadlines apply to legacy devices.

What the IVDR covers

An in vitro diagnostic medical device is a device intended to examine specimens from the human body, including blood and tissue donations, to provide information about a physiological or pathological process or state, a congenital condition, predisposition to a condition, safety and compatibility with potential recipients, treatment response, or to define therapeutic measures. It includes reagents, calibrators, controls, instruments, software and specimen receptacles. Companion diagnostics, self-tests and near-patient tests are all in scope, and software that processes IVD data may qualify as an IVD in its own right. See our guide on whether software is a medical device for the qualification logic.

Classification under Annex VIII

Annex VIII sets seven classification rules and implementing rules. The class reflects the risk to the individual patient and to public health.

Class	Risk	Examples	Notified body?
A	Low individual and public health risk	General laboratory reagents, specimen receptacles, instruments	No, if non-sterile; yes, if sterile
B	Moderate individual and/or low public health risk	Many clinical chemistry assays, pregnancy self-tests, some general-purpose tests	Yes
C	High individual and/or moderate public health risk	Companion diagnostics, cancer screening and staging tests, genetic tests, HIV and hepatitis monitoring	Yes
D	High individual and high public health risk	Blood donor screening for HIV, HBV, HCV; blood group typing for transfusion	Yes, with extra review

The classification rules look at the intended purpose, the condition being detected, the consequence of a wrong result and the setting (for example self-testing or near-patient testing). Rules 1 to 4 place the highest-risk uses (for example blood screening, infectious disease detection, companion diagnostics and most self-tests) in Class D or C, while rule 6 acts as a default and places devices not covered by another rule in Class B. Document the rule you applied and why. Our overview of device classification explains the general method.

Conformity assessment routes

• Class A (non-sterile): the manufacturer draws up the technical documentation and the declaration of conformity and affixes the CE mark.
• Class A sterile and Class B: a notified body assesses the quality management system and technical documentation sampling, depending on the route chosen.
• Class C: full quality management system assessment, plus assessment of the technical documentation for representative devices (or for each device under the alternative route). Companion diagnostics also involve consultation with a medicines authority.
• Class D: as for Class C, with additional steps: review of the performance evaluation, consultation with an EU reference laboratory where applicable, and batch verification. Common specifications set additional requirements for several Class D tests.

Self-tests and near-patient tests also need evidence that lay users or non-laboratory users can use them correctly, so usability matters as much as analytical performance. See usability engineering (IEC 62366) for the human factors method.

Performance evaluation

The IVDR requires a continuous performance evaluation, planned, documented and updated across the lifecycle. It has three parts:

1. Scientific validity: the association of the analyte with a clinical condition or physiological state, shown through literature, guidelines and your own data.
2. Analytical performance: the ability of the device to detect or measure the analyte correctly, including accuracy, precision, analytical sensitivity and specificity, limits of detection and quantitation, interference, cross-reactivity, stability and, for software, verification and validation.
3. Clinical performance: the ability to yield results that correlate with a particular clinical condition for the intended population, shown through sensitivity, specificity, predictive values and, where appropriate, a performance study.

These are captured in a performance evaluation plan and a performance evaluation report. For Class C and D devices (apart from devices for performance studies), manufacturers also prepare a Summary of Safety and Performance (SSP), which the notified body validates and which is made available to the public through EUDAMED. Where a new clinical performance study is needed, it follows the IVDR rules for performance studies, including ethics, sponsor duties and, where relevant, ISO 20916.

Quality system, PRRC and post-market duties

• Quality management system: Article 10(8) requires a QMS. ISO 13485 is the usual basis. See ISO 13485 training and audit readiness.
• Person responsible for regulatory compliance (PRRC): required for every manufacturer, with defined qualifications.
• Post-market surveillance: a PMS system and plan, with a PMS report for Class A and B or a periodic safety update report (PSUR) for Class C and D. Post-market performance follow-up (PMPF) is part of continuous performance evaluation. See post-market surveillance.
• Vigilance: serious incident and field safety corrective action reporting, aligned with the process in our guide to recalls and FSCAs.
• UDI and EUDAMED: IVD manufacturers face the same registration obligations as device manufacturers. See the EUDAMED guide and UDI in the EU and US.

Transition deadlines for legacy devices

Regulation (EU) 2024/1860 extended the IVDR transition for devices that were lawfully on the market under the IVDD, with certificates or declarations of conformity issued before 26 May 2022. The extension depends on milestones, not just on the date.

IVDR class	Application to notified body by	Written agreement by	Legacy device may stay on the market until
D	26 May 2025	26 September 2025	31 December 2027
C	26 May 2026	26 September 2026	31 December 2028
B and A sterile	26 May 2027	26 September 2027	31 December 2029

Conditions apply throughout: the device must have been legally on the market under the IVDD before 26 May 2022, it must continue to comply with the directive and not present an unacceptable risk, it must not undergo significant changes in design or intended purpose, and the manufacturer must have an IVDR-compliant QMS in place and follow the milestones. Missing a milestone means you cannot rely on the transition for that device. Devices that were never on the market under the IVDD, and Class A non-sterile devices, do not benefit from the extension.

In-house devices made and used within health institutions have their own staged requirements under Article 5(5), with a later date for the justification that no equivalent device is available on the market. Laboratories should check the current text and national implementation.

A practical IVDR plan for a legacy portfolio

1. Re-classify each product under Annex VIII and record the rule used.
2. Map the milestones for each class and set internal dates ahead of the legal ones.
3. Prioritise. Begin with the products with the nearest deadline and with the largest revenue and clinical impact. Retire or divest products that will not repay the cost.
4. Secure notified body capacity. Apply early, agree the written agreement and plan for a long review.
5. Close evidence gaps. Build performance evaluation plans, run missing analytical and clinical studies and prepare the SSP.
6. Upgrade the QMS. Add IVDR-specific processes for PMS, PMPF, vigilance, PRRC and UDI.
7. Control change. Avoid significant changes to transition devices. See change control for 510(k) and MDR for how to assess significance.
8. Register in EUDAMED within the applicable deadlines.

The policy outlook

In December 2025 the European Commission proposed a wider simplification of both the MDR and the IVDR. At the time of writing it is a proposal going through the Parliament and the Council and is not law, so the regulations and deadlines above still apply. Follow the legislative progress, but do not delay milestone work in the hope of change.

Common mistakes

• Assuming an old IVDD self-declaration still protects the device after the milestone dates have passed.
• Choosing the wrong classification rule, then facing a different notified body route late in the project.
• Under-estimating the clinical performance evidence needed for Class C.
• Making a significant change to a transition device and losing the transition.
• Applying to a notified body without an IVDR-compliant QMS.
• Ignoring the PRRC, PMS and vigilance duties that apply regardless of the transition.

Frequently asked questions

Which IVDs still do not need a notified body?

Class A non-sterile devices, such as many general laboratory products. Everything else, including Class A sterile devices, needs a notified body.

What if my legacy device was self-declared under the IVDD?

It can use the extended transition only if it meets the conditions and milestones for its IVDR class. If it moves into class B, C or D, you must apply to a notified body by the date for that class.

Do companion diagnostics have special rules?

Yes. They are generally Class C, and the notified body must consult a medicines authority (the EMA or a national authority) on the suitability of the device for the medicine it supports.

What is the Summary of Safety and Performance?

It is a public document for Class C and D devices that summarises intended purpose, performance and safety evidence, written to be understood by the intended user and, for self-tests, the lay user. The notified body validates it.

Is the IVDR being replaced?

The Commission has proposed simplification changes, but the IVDR remains in force and the proposal has not been adopted. Treat the current text and transition rules as the basis for your plan.

IVDR deadlines, conditions and guidance change, and national rules for in-house devices differ. Confirm the current position with your notified body, the Commission and your regulatory advisers before relying on this guide for a specific product.

Related reading

• EU medical device regulations (MDR and IVDR): the broader map of the EU system.
• EUDAMED guide: registration duties and deadlines.
• Post-market surveillance: PMS, PSUR and vigilance.
• Clinical evaluation under EU MDR: compare with IVDR performance evaluation.
• UDI in the EU and US: identifiers for IVDs.

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