CLASSIFICATION OF MEDICAL DEVICES

US FDA has classified all the devices in three classes namely, Class I, Class II and Class III. Class I devices are subject to the least regulatory control. They present minimal potential for harm to the user and are often simpler in design than Class II or Class III devices. Examples of Class I devices include elastic bandages, examination gloves, and hand-held surgical instruments.Most Class I devices are exempt from the premarket notification and/or good manufacturing practices regulation. Class II devices are those for which general controls alone are insufficient to assure safety and effectiveness, and existing methods are available to provide such assurances. In addition to complying with general controls, Class II devices are also subject to special controls. Special controls may include special labeling requirements, mandatory performance standards and postmarket surveillance. Examples of Class II devices include powered wheelchairs, infusion pumps, and surgical drapes. Class III is the most stringent regulatory category for devices. Class III devices are those for which insufficient information exists to assure safety and effectiveness solely through general or special controls. Class III devices are usually those that support or sustain human life, are of substantial importance in preventing impairment of human health, or which present a potential, unreasonable risk of illness or injury. Examples of Class III devices which require a premarket approval include replacement heart valves, silicone gel-filled breast implants, and implanted cerebella stimulators.

In other countries medical devices have been classified usually into four classes namely Class I, IIa, IIb and III (sometimes they are also classified as Class A,B,C & D. The Global Harmonized Task Force (GHTF) has recommended ABCD classes. The risk associated with Class I or A is lowest and with Class III or D is greatest.

In India still system of classifying devices has not been introduced. But looking at the on-going efforts to make an umbrella regulation to cover all the medical devices under the ambit of Drugs & Cosmetic Act & Rules, classification of devices will be a must. Whether in India the devices are classified or not, internationally they are. Hence, once a manufacturer determines that his product is a medical device, it is important for him to know in which class his medical device falls. This will help him in realizing the extent of control to be exercised by the regulatory agencies on his product. In the past, in absence of such classification, manufacturers were not serious about applicability of GMP requirements to their manufacturing units. At times such situations invite unnecessary arguments between the manufacturer and the regulator.

In some countries like Australia, another class of Active Implantable Medical Devices has been included. Since GHTF classification rules are likely to be adopted world-over, the present information is mainly based upon document.

1.0 The Determination of Device Class using this Rules-based System

General classification system for medical devices

The manufacturer should:

1. Decide if the product concerned is a medical device, using the appropriate definition.

NOTE :

Medical devices that are used for the in vitro examination of specimens derived from the human body are not covered by the classification rules within this document (see Scope).

2. Document the intended use of the medical device.

3. Take into consideration all the rules that follow in order to establish the proper classification for the device, noting that where a medical device has features that place it into more than one class, classification and conformity assessment should be based on the highest class indicated.

4. Determine if the device is subject to special national rules that apply within a particular jurisdiction.

Notes :

Once a rules-based system has been adopted, modifications may occasionally be required. For example, where through post-market experience, a level of risk for a type of medical device, classified using the criteria found in this guidance document is no longer appropriate, consideration should be given to re-classification of the device type by a change to the rules.

Similarly, the historical knowledge of a device may necessitate a different class than the one assigned by the initial classification. Unlike the principle of reclassification after post-market experience with a device, this principle of historical knowledge should be applied immediately when the initial classification yields an inappropriate result.

Where special national rules are applied, resulting in a device class other than that suggested by the present rules, then a different conformity assessment procedure may be indicated. This may have an effect on the acceptability of such devices for free movement in countries where these present rules have been adopted unless other, or additional, conformity assessment procedures are carried out.

2.0 Initial Classification Rules

The actual classification of each device depends on the claims made by the manufacturer and on its intended use. While the provision of illustrative examples in the table that follows is helpful when interpreting the purpose of each rule, it must be emphasised that the actual classification of a particular device must be considered individually, taking account of its design and intended use.

For more information on classification rules applicable to various types of medical devices, please write to us or see Document No. GHTF/SG1/N15:2006 at www.ghtf.org

If you  have questions related to this subject, please write to Dr G L Jain at  drgljain@medisourceasia.com

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