Medtech MDD (93/42/EEC) vs MDR (2017/745)
MDD vs MDR: what changed and what your transition actually needs
The EU Medical Device Regulation (2017/745) replaced the Medical Device Directive (93/42/EEC). It widens scope, up-classifies most software, demands far more clinical evidence and post-market surveillance, mandates UDI and EUDAMED, and requires re-certification by a notified body. Legacy MDD devices must transition by 31 December 2027 or 2028 depending on class.
| MDD (93/42/EEC) | MDR (2017/745) | |
|---|---|---|
| Legal instrument | A Directive — transposed into each member state's national law | A Regulation — directly applicable across the EU, with less national variation |
| Scope | Medical devices as defined in the Directive | Wider — adds certain non-medical/aesthetic products (Annex XVI) and tightens rules on reprocessing and software |
| Classification | 18 rules; much standalone software sat in Class I | 22 rules; Rule 11 pushes most software to Class IIa or higher; reusable surgical instruments become Class Ir |
| Clinical evidence | Lighter; the equivalence route was widely used | Much heavier — clinical evaluation plus ongoing PMCF; equivalence is far harder to claim |
| Notified body | Certification under the Directive | Re-designation under MDR required — a capacity bottleneck driving the transition timeline |
| Traceability | Limited unique-identification requirements | UDI mandatory; registration in the EUDAMED database |
| Post-market | Basic vigilance reporting | Systematic PMS, periodic safety update reports (PSUR), PMCF, and trend reporting |
| Organisational | No equivalent requirement | A Person Responsible for Regulatory Compliance (PRRC) is required |
| Transition deadline | Being phased out | Legacy devices: 31 Dec 2027 (Class III + IIb implantable) or 31 Dec 2028 (other), per Regulation 2023/607 |
The MDD and MDR are not two options you choose between — the MDR replaced the MDD, and the only live question is how cleanly a legacy device crosses over. New devices are MDR-only. Devices CE-marked under the MDD can stay on the market under transitional provisions, but each must be re-certified by an MDR-designated notified body by its class deadline.
What changed is not cosmetic. The MDR is a Regulation, so it applies directly across the EU with less room for national interpretation. It widens scope, and — through Rule 11 — up-classifies most standalone software, which is the single change that catches software-driven device makers by surprise: a product that was comfortably Class I under the MDD often lands in Class IIa or higher under the MDR, pulling in a notified body where none was needed before. The clinical-evidence bar rises sharply, the equivalence shortcut narrows, and post-market surveillance becomes a standing obligation (PMS, PSUR, PMCF, trend reporting) rather than reactive vigilance. UDI and EUDAMED add a traceability layer, and every manufacturer needs a PRRC.
The practical bottleneck is rarely the legal text — it is notified-body capacity and the evidence reassembly needed to move a legacy technical file onto MDR’s heavier clinical and post-market requirements. Treat your class deadline (31 December 2027 or 2028) as the date your MDR certificate must be issued by, and work backwards from the notified-body queue, not the calendar. The full date cluster and the 2024 application milestones are on the EU MDR transition tracker.
A useful way to scope the work: inventory every legacy device, re-run classification under the MDR’s 22 rules (especially Rule 11 for software), and map each device’s existing evidence against the MDR’s clinical and post-market gaps. The devices that miss the deadline are almost always the ones where regulatory owned the transition alone and engineering found out late.
Sources
Last reviewed . Pathways and rules change — confirm against the cited primary source.