IVDR (EU 2017/746): Classification, Notified Body Requirements, and Transition Deadlines

Regulation (EU) 2017/746, the In Vitro Diagnostic Medical Devices Regulation (IVDR), replaced the older In Vitro Diagnostic Medical Devices Directive (98/79/EC, “IVDD”) as the legal framework for placing in vitro diagnostic (IVD) devices on the EU market. It entered into force on 26 May 2017 and became fully applicable on 26 May 2022. For a diagnostics developer, the practical effect of IVDR is not one new rule but three that compound: a stricter, rule-based risk classification (Annex VIII), a conformity-assessment route that now routes most devices through a Notified Body instead of manufacturer self-declaration, and an extended set of transitional deadlines that are still actively running today.

This guide works through those three pieces in the order a developer actually needs them: how a device gets classified, what that classification then requires for conformity assessment, and which transition deadline applies right now.

How IVDR Classifies a Device: Annex VIII and the Seven Rules

Unlike IVDD, which classified devices by matching them against fixed lists (Annex II List A, List B, “devices for self-testing,” and everything else by default), IVDR classifies devices by applying seven risk-based rules set out in Annex VIII. Each rule targets a category of intended purpose, and a device is assigned to the highest class any applicable rule produces. In outline:

• Rule 1 covers devices intended to detect the presence of, or exposure to, a transmissible agent in blood, blood components, cells, tissues or organs intended for transfusion or transplantation, where an incorrect result carries a high risk of death or severe disability for the recipient or the individual tested. These devices are Class D.
• Rule 2 covers devices for blood grouping, tissue typing, or detecting transmissible-agent infection where an erroneous result creates a high public-health risk (e.g. HIV, HBV, HCV, HTLV screening). Also generally Class D.
• Rule 3 is the broadest and covers most everyday diagnostic use: determining infectious disease status where there is a risk of propagation, screening for congenital disorders, monitoring therapeutic levels, staging disease, detecting genetic markers or predisposition, and companion diagnostics. Depending on the specific sub-case this rule produces Class C in most instances, with a smaller number of high-severity sub-cases reaching Class D.
• Rule 4 governs self-testing and near-patient-testing devices specifically. A near-patient test is generally assigned the same class as the equivalent laboratory device; self-testing devices are typically Class C unless already captured at a higher class by another rule, with a narrow set of low-risk self-tests (e.g. pregnancy testing) reaching only Class B.
• Rule 5 covers general-purpose laboratory reagents, instruments, and products with no stated or claimed specific intended purpose (buffer solutions, general culture media, and similar). These fall to Class A.
• Rule 6 is the residual rule for devices not covered by Rules 1-5 or 7, which reach Class B by default.
• Rule 7 covers instruments specifically intended for IVD procedures; these are generally Class B, or Class A if the instrument does not itself perform a measurement.

The practical result, confirmed by MDCG 2020-16 rev.4 (“Guidance on Classification Rules for in vitro Diagnostic Medical Devices under Regulation (EU) 2017/746”), is that the great majority of assays that actually inform a clinical decision land in Class B, C, or D — general laboratory consumables and simple instruments are the main devices left in Class A. A manufacturer should classify against the full Annex VIII rule set, not by analogy to a device’s old IVDD category: the rule structure is different enough that many devices move up, not sideways.

The Conformity-Assessment Shift: Self-Certification Is No Longer the Default

The classification outcome matters because it determines the conformity-assessment route, and this is where IVDR made its biggest practical change. Under IVDD, the large majority of IVDs — commonly cited industry estimates put the figure around 80-90% — were self-certified: the manufacturer alone declared conformity, with no third-party (Notified Body) review at all. Only devices on the IVDD’s specific higher-risk lists needed Notified Body involvement.

IVDR inverts that ratio. Under the Annex VIII classes:

• Class A, non-sterile devices remain on manufacturer self-declaration, with no Notified Body role — the one class where IVDR still works like most of IVDD did.
• Class A, sterile devices require Notified Body involvement limited to the aspects of manufacture relating to achieving and maintaining sterility.
• Class B, C, and D devices all require a Notified Body to review the manufacturer’s quality management system and, with increasing scrutiny at each class, the technical documentation itself. Class C additionally triggers, for certain device categories such as companion diagnostics, a consultation procedure with a national reference laboratory or an EU reference laboratory and, in some cases, a relevant expert panel. Class D goes further still: it requires EU reference laboratory verification of the manufacturer’s performance claims and batch testing where an EU reference laboratory has been designated for that device category.

Because most real diagnostic assays classify into B, C, or D under the rules above, the practical consequence is that most IVDs sold in the EU today need a Notified Body relationship they did not need under IVDD — and Notified Body capacity for IVDR has been a persistent bottleneck industry-wide since 2022, which is part of why the transitional deadlines below exist at all.

Current IVDR Transition Deadlines (Article 110, as Extended by Regulation (EU) 2022/112)

IVDR became fully applicable on 26 May 2022, but the original transition period in Article 110 was too short relative to real Notified Body capacity, so Regulation (EU) 2022/112 extended it. The extended deadlines run by device class — broadly, the highest-risk devices got the least extra time, the lowest-risk devices got the most:

• Class D devices: extended deadline of 26 May 2025.
• Class C devices: extended deadline of 26 May 2026.
• Class B devices, and Class A devices placed on the market in sterile condition: extended deadline of 26 May 2027.

These extended deadlines are conditional, not automatic — in general they apply only to a device that was already legally placed on the market under IVDD before 26 May 2022 (i.e. it carried a valid IVDD declaration of conformity or, where one was required, a still-valid IVDD certificate), continues to meet IVDD requirements, and has not undergone a significant change in design or intended purpose. MDCG 2021-4 rev.1 sets out the detailed conditions specifically for Class D devices moving through this transitional route, and MDCG 2022-15 covers the market-surveillance expectations for devices still relying on it.

As of today, this means the Class D and Class C transition windows have already closed — any Class D or Class C device still on the market now must hold full IVDR conformity, not a carried-over IVDD status. The one transitional window still open is for Class B devices and sterile Class A devices, running to 26 May 2027. A manufacturer relying on any of these dates should confirm current status directly against Article 110 IVDR and the MDCG guidance above rather than a secondary summary, since a further legislative amendment is always possible and would supersede this without notice to any one source.

What This Means in Practice for a Diagnostics Developer

1. Classify early, against the full Annex VIII rule set — not by carrying over an IVDD category. A device that was self-certified under IVDD can land in Class B, C, or even D under IVDR, which changes the entire regulatory pathway and timeline for it.
2. If the device lands in Class B, C, or D, secure a Notified Body relationship as early as possible. Given ongoing Notified Body capacity constraints, this is frequently the longest item on the critical path to market — longer than the technical work itself for many manufacturers.
3. Build the technical documentation and performance evaluation file to IVDR’s standard from the outset, including the Performance Evaluation Report, Scientific Validity Report, Analytical and Clinical Performance Reports, and a Post-Market Performance Follow-up (PMPF) plan — these largely did not exist in this form under IVDD and cannot be assembled quickly at the end of a project.
4. Register in EUDAMED for the modules currently mandatory (Actor registration and UDI/Device registration as of the applicable dates), and obtain a Single Registration Number (SRN) as an economic operator before placing a device on the market — see CASRAI’s EUDAMED guide for the current module-by-module status.
5. Confirm whether transitional provisions genuinely apply to an existing device rather than assuming they do — the conditions above (valid prior certification, no significant design change, continued IVDD compliance) are specific, and a device that fails any of them needs full IVDR conformity now, regardless of its class.

Related IVDR and Device-Quality Requirements

IVDR classification and conformity assessment do not sit in isolation from the rest of a device manufacturer’s quality system. A Class B, C, or D IVD needs a certified quality management system — see CASRAI’s guides to ISO 13485 and ISO 13485 certification — and a risk management file built to ISO 14971. Devices that include software components (increasingly common for algorithm-driven diagnostics) are separately subject to IEC 62304 software lifecycle requirements, and a standalone diagnostic algorithm may itself qualify as Software as a Medical Device (SaMD). Once a device is on the market, any corrective action taken in the field is governed by the same Field Safety Corrective Action (FSCA) framework that applies under EU MDR. For the people managing this across an organization, CASRAI’s guide to Regulatory Affairs Certification (RAC) covers the credential most associated with this work.

Frequently Asked Questions

What is Regulation (EU) 2017/746?

It is the EU’s In Vitro Diagnostic Medical Devices Regulation (IVDR), the legal framework governing how in vitro diagnostic devices are classified, assessed for conformity, and monitored after they reach the EU market. It replaced Directive 98/79/EC (IVDD) and has applied in full since 26 May 2022.

What are the IVDR device classes?

IVDR uses four risk classes — A (lowest risk) through D (highest risk) — assigned by applying the seven rules in Annex VIII to a device’s intended purpose, rather than by matching it against a fixed list as IVDD did.

Does my IVD need Notified Body involvement under IVDR?

Only non-sterile Class A devices remain on manufacturer self-declaration with no Notified Body role. Sterile Class A devices need limited Notified Body review of sterility aspects, and every Class B, C, or D device needs a Notified Body to review the quality management system and, increasingly by class, the technical documentation itself.

What happened to IVDD self-certification?

Under IVDD, most IVDs were self-certified with no third-party review. IVDR reverses that: because most real diagnostic assays now classify into Class B, C, or D, most devices that could previously be self-certified now require Notified Body conformity assessment.

What is the current IVDR transition deadline?

Under Article 110 IVDR as extended by Regulation (EU) 2022/112, the transitional deadlines were 26 May 2025 for Class D devices and 26 May 2026 for Class C devices — both now past — leaving only the Class B and sterile Class A deadline of 26 May 2027 still open, and only for devices that meet the specific conditions of the transitional route (valid prior IVDD status, no significant design change, continued IVDD compliance).