Substance based Medical Device Classification under MDR - Rule 21

[ciccina]

Hello everybody!
I’m studying the new MDR for medical device and I have a question related to classification. One of the new rule introduced in the MDR is the rule 21 which includes substance based medical devices. If I well understood all these medical devices will be classified under rule 21 and the class of risk will vary depend on the product absorption.
Can you give me practical example for each risk class (IIb, IIa and III)?
I have a medical device (substance based) for the treatment of acidity and gastroesophageal reflux which acts in the stomach but is then evacuated through faeces. In which class does it fall?
I think class IIb, rule 21 but I’m not sure.

Thank you in advance!

 

[RobertvanBoxtel]

The product you refer to and when you can prove the intended purpose and related mechanism of action not to be pharmacological (Etc), most likely it will be considered a medical device. Be sure that you can prove the mechanism of action and that indeed it is not absorbed in the body.

Regarding rule 21:
that is a correct assessment, if indeed the absorption is not applicable.

 

[pkost]

Devices that are composed of substances or of combinations of substances that are intended to be introduced into the human body via a body orifice or applied to the skin and that are absorbed by or locally dispersed in the human body are classified as:

— class III if they, or their products of metabolism, are systemically absorbed by the human body in order to achieve the intended purpose;

— class III if they achieve their intended purpose in the stomach or lower gastrointestinal tract and they, or their products of metabolism, are systemically absorbed by the human body;
— class IIa if they are applied to the skin or if they are applied in the nasal or oral cavity as far as the pharynx, and achieve their intended purpose on those cavities; and
— class IIb in all other cases.

If you are looking at a sodium alginate type product then that would be Class III as it achieves its purpose in the stomach; it is irrelevent that the products are not systematically absorbed

It is introduced orally; it is intended to locally disperse in the stomach. It achieves its intended purpose in the stomach

you may be able to justify IIb if you can demonstrate that the action is achieved by coating the oesophagus (you can't do this with sodium alginate though)

 

[Ben S UK]

Is there a definition of 'systemic absorption'?

I imagine most substances that enter the stomach, will to some extent be absorbed. I'd be keen to know how this is intended to be interpreted?

 

[cam5603]

I have the same issue with a product : spray for ear hygiene.

For me the rule 21 has to be applied (Invasive medical device containing a substance (sea water) locally dispersed in ear).

I think that it could be a class IIb ? What do you think ?

 

[TycoSQR]

Hi,

I have a similar issue with that rule 21.
We produce a sterile gel intended for cleansing eyelids affectd by pathology, helping maintain hydratation and encouraging healing.

Under the MDD it is a non invasive which comes into contact with injured skin and belongs to class IIa.

Under MDR this rule still applies but there is also rule 21 and this bit :
class IIa if they are applied to the skin or if they are applied in the nasal or oral cavity as far as the pharynx, and achieve their intended purpose on those cavities;

I is still a IIa medical device but the only difference is that under rule 21 we have to perform studies such as those described in annex II 6.2c :
- absorption, distribution, metabolism and excretion;
- possible interactions of those substances, or of their products of metabolism in the human body, with other devices, medicinal products or other substances, considering the target population, and its associated medical conditions;
- local tolerance; and
- toxicity, including single-dose toxicity, repeat-dose toxicity, genotoxicity, carcinogenicity and reproductive and developmental toxicity, as applicable depending on the level and nature of exposure to the device.

Our device is not intended to be introduced into the body but is that enough to avoid this rule ?

 

[Quita]

Hi TycoSQR,

What did you decide about the studies in annex II 6.2c?

Thanks in advance for your reply!

 

[TycoSQR]

Hi TycoSQR,

What did you decide about the studies in annex II 6.2c?

Thanks in advance for your reply!

Hi,

Sorry for the late reply.

We will try to assess the mode of action of each substance through literature review and if possible prepare a rational to justify not performing ADME studies required.

If the information is not present our provider will propose additional tests that may be able to mitigate the need for ADME tests.

I guess I will know if it worked by the end of Q1 2019.

 

[Quita]

Hi TycoSQR,

Sounds like an acceptable approach! What kind of additional tests are you referring to? And could you please let me know if it worked end of Q1?

Many thanks in advance!

 

[efren_reina]

Hi everyone,

What a interesting discussion!
As you mentioned before there are a different issues related with the new rule 21. The first question coming into my mind is about the definitions of "locally dispersed" or "sistemically absorved". Regarding these questions... do you know if it is there some documents availables related with this terms??

My feeling is that even you can prove the inteded prupose and related mechanism of action of the device correctly if there is not any definitions which match with any phenomen... The demonstration is not without doubts.

Btw, the ADME tests referred above are only placed with the aim to characterize pharma devices but no for medical devices (yet). Thus, IMO the verification and/or validation of this kind of devices -which can be related with rule 21- will be conducting through a new Commmon Specification or a new specific standard for these devices. So what's your opinion on that point? Do you recieve any feedback from NB regarding these issues?

Thanks!!