EU MDR: What Changed From the Directive

Regulation (EU) 2017/745, the Medical Device Regulation, replaced the Medical Device Directive. It applied from May 2021 after a delay, and the change is larger than the name suggests.

A regulation applies directly across member states, where a directive had to be transposed into national law. That alone removed a layer of national variation.

What actually got harder

More clinical evidence. MDR raised the expectation for clinical data supporting a device, and narrowed when equivalence to another manufacturer's device can be claimed. Devices that were on the market for years under the directive with thin clinical files are the ones this hit.

Reclassification. Several device types moved up a class. Software in particular: Rule 11 pushed much clinical decision support into Class IIa or higher, and a device that was self-certified Class I under the MDD may need a notified body under MDR.

Fewer self-certified devices. The MDR removed a route many manufacturers relied on.

Post-market obligations became explicit. A post-market surveillance plan, a PMCF plan, periodic safety update reports for Class IIa and above, and a summary of safety and clinical performance for implantable and Class III devices.

Person responsible for regulatory compliance. A named individual with defined qualifications inside the manufacturer, which the directive did not require.

UDI and EUDAMED, which the directive had no equivalent of.

The technical documentation

Annexes II and III set out what the file contains: device description and specification, information to be supplied by the manufacturer, design and manufacturing information, the general safety and performance requirements with evidence against each, benefit-risk and risk management, product verification and validation including the clinical evaluation, and the post-market surveillance documentation.

The general safety and performance requirements are a checklist you must answer item by item, stating whether each applies and how conformity is demonstrated. A file that says "applicable" without pointing at the evidence is the common gap.

The transition

Original deadlines slipped. Extensions moved certificate validity for legacy devices well past the original 2024 date, on conditions: the manufacturer must have applied to a notified body, have a compliant quality management system, and the device must not have significantly changed.

The last condition catches people. A significant change under the directive certificate ends the transition benefit for that device.