Custom-made devices under the EU MDR

The definition turns on patient-specific design and prescription control. The device must be made in accordance with a written prescription from a person authorised by national law, the prescription must give specific design characteristics under that person's responsibility, and the device must be intended for one particular patient or user.

The exclusion matters: a mass-produced device that is only adapted to a professional user's requirements is not a custom-made device. A device mass-produced by industrial manufacturing processes under written prescriptions is also outside the custom-made definition.

Before placing a custom-made device on the market, the manufacturer must follow Annex XIII and draw up the required statement. Article 21 also requires the device to be accompanied by that statement, made available to the identified patient or user.

Annex XIII requires documentation that lets competent authorities understand the design, manufacture, and performance of the device, including expected performance, so they can assess conformity. The manufacturer must keep the statement for at least 10 years after placing the device on the market, or at least 15 years for implantable devices.

Custom-made devices do not follow the standard class I, IIa, IIb, or III conformity assessment routes used for non-custom-made devices. Article 52(8) points custom-made-device manufacturers to Annex XIII and the Annex XIII statement before placing the device on the market.

There is an added rule for class III custom-made implantable devices: in addition to Annex XIII, the manufacturer must undergo a conformity assessment under Chapter I of Annex IX or may choose Part A of Annex XI.

Annex XIII requires the manufacturer to review and document post-production experience, including PMCF where applicable, and to apply necessary corrective action. Serious incidents and field safety corrective actions must be reported under Article 87 when the manufacturer learns of them.

For class IIa, IIb, and III custom-made devices, Article 86 and MDCG 2022-21 treat the PSUR as part of the Annex XIII documentation. MDCG 2022-21 also states that custom-made-device PSURs may cover device groups or families if the manufacturer justifies the grouping.