Volume 7: Medicines and Cosmetics
5. Issue of guidelines
Guidelines on medical devices
Introduction
Responsibility for medical devices
Issue of guidelines on medical devices: a chronological account
February 1989
March 1989

Introduction

5.62 We noted in Chapter 2 that, prior to 1993, medical devices were not licensed under the Medicines Act, but were subject to a voluntary Manufacturers Registration Scheme (MRS). Being unlicensed, they were not covered by the CSM/VPC guidelines. However, the Supplies Technology Division (STD) of Procurement Directorate (PD), which monitored the MRS, identified the implications of BSE for such devices. It was notified in February 1989 of the steps being taken in relation to medicinal products by MAFF and Medicines Division, and obtained at the same time an advance copy of the Southwood Report. Guidelines to MRS members, slightly adapted from those issued by the CSM/VPC, were provided in March 1989.

Responsibility for medical devices

5.63 Medical devices differ from medicines in that their principal intended action is typically achieved by a physical rather than pharmacological, immunological or metabolic means. Certain dental and surgical materials, such as catgut, required a licence under the Medicines Act, and fell within the remit of the CDSM: we are not concerned with such products in this section. Examples of medical devices that were outside the licensing system include heart valves, pacemakers and hip joints. At the time when BSE emerged, such devices were regulated only by the MRS. ¹

5.64 As explained in vol. 14: Responsibilities for Human and Animal Health, STD was responsible for promoting and investigating the safety of a wide range of medical devices and equipment. Miss Marilyn Duncan was the Grade 5 in charge of much of this work in STD, reporting to the Director of PD. ²

Issue of guidelines on medical devices: a chronological account

February 1989

5.65 Mr Burton, who was head of the Pharmaceutical Supply and Technology Section (PSTS) of STD, told us that on 17 February 1989 he received a minute from Mr Hagger alerting him to recent developments on BSE. The minute outlined the recent steps taken by DH and MAFF and invited him to attend the HVMBG meeting scheduled for 22 February 1989. ³

5.66 Mr Burton told us that immediately upon reading Mr Hagger's minute he realised that it had implications for his areas of responsibility, namely supplies of pharmaceuticals; the safety of medical devices not covered by the Medicines Act; and product licences for which the Secretary of State was the licence holder, which had historically been held by STD. Mr Burton obtained a copy of the Southwood Report and discovered that it concentrated on food and pharmaceuticals, and appeared to omit reference to the bulk of unlicensed products. ⁴

5.67 Staff within STD met to discuss BSE on 21 February prior to the HVMBG meeting that Mr Burton was to attend the next day. During the meeting three areas of interest concerning BSE were identified: the effect on pharmaceutical supplies including vaccines, named patient supplies and NHS in-house manufactured products; the effect on product licences held by STD on behalf of the Secretary of State for Health; and the implications for control and supply of those medical devices derived from animal sources. ⁵ Mr Burton attended the second HVMBG meeting on 22 February. We have discussed that meeting in paragraph 5.37 above.

5.68 On 22 February, after the HVMBG meeting, Miss Duncan sent a minute to Dr Metters, Senior Principal Medical Officer, MED SEB. She said:

As you will know from Dr Sutton we only became aware of the Southwood Report on Friday and it is clear that those compiling the report were unaware that there are a range of unlicensed medical devices made from or containing material of bovine origin. ⁶

5.69 Miss Duncan explained that STD had already prepared a provisional list of devices that they knew, from their MRS data and from individual specialist knowledge, contained material of animal origin. She said they had considerable information on how the companies sterilised their products, but noted that there was regrettably little scientific information on how effective these processes were against the infective 'material' in this case. She was asking Dr Hoxey to consult further on this. ⁷

5.70 Miss Duncan suggested it was clear that the Department needed to take action to complement that to be taken for licensed products; she proposed that a formal letter and questionnaire and guidance notes be faxed to UK companies known to use bovine materials, and sent by post to all medical device companies which might conceivably use animal materials, the majority of which were in the USA.

5.71 Dr Metters agreed with Miss Duncan, and asked that Dr Pickles be kept closely informed. ⁸

5.72 On 23 February, Mr Burton attended the CSM meeting. He told us that insulin, heparin, heart valves and dura mater were considered by the CSM, in addition to other medicinal products using bovine material. ⁹

March 1989

5.73 Guidelines and a questionnaire relating to medical devices were sent on 17 March 1989, under cover of a letter signed by Miss Duncan, to 328 recipients drawn from the membership of the MRS in relation to sterile medical devices and surgical products. ¹⁰ The letter stated that 'in parallel' with the action taken by the Licensing Authority on medicines, PD/STD was 'considering the implications of the BSE agent for those surgical implants and blood contact medical devices which fell outside the scope of the Medicines Act'. It continued:

Supplies Technology Division, in conjunction with the UK Committee on Safety of Medicines, has considered the Southwood Report and agrees that the risk to man of infection by BSE and other scrapie-like agents resulting from the use of such devices is remote. As a purely precautionary measure, we have developed the enclosed guidelines for manufacturers of medical devices who use bovine, or other animal materials, either as a component or in the production process. The guidance represents 'best practice' for future manufacture and outlines the steps which should now be taken to implement it. It is realised that this guidance may not be fully applicable in all circumstances and it will be further developed in the light of experience. ¹¹

5.74 Recipients were asked to respond by 1 May 1989.

5.75 The guidelines attached to the letter read as follows:

1. Scope

It is recommended that all products in the following categories, which are supplied to hospitals in the United Kingdom, and which do not fall under the remit of the Medicines Act, should in general conform to this guidance if they contain material from a bovine source,* or if bovine material has been used during their manufacture.

Categories:

a). Biological heart valves.

b). Other cardiovascular implants (eg vascular prostheses, cardiac patches etc)

c). Orthopaedic implants such as tendons, bone grafts etc.

d). Single use sterile devices that use such animal derivatives as heparin and gelatin in, for example, coatings.

e). Any other implantable products or products which come into contact with blood or the lymphatic system and which utilise materials of bovine origin.

a. Tissues to be excluded

Brain or neural tissue, spleen, thymus and other lymphoid tissue, placental tissue or cell cultures of bovine origin should not be used in manufacture.

b. Cattle sources for all other tissues

Bovine material should come from animals, taken from a closed herd in the female line since 1980, in which no animal has been clinically suspected of having BSE, and which has not been fed rations containing ruminant derived proteins during that period.

Collection techniques

All possible measures should be taken to avoid contamination of the bovine material with BSE, in particular:

No tissue should be used when collected postmortem from a bovine animal if brain penetrative stunning has been used.

All tissue collected should be taken using sterile equipment. Needles, syringes, scalpel blades etc should be used as disposable items.

It is recommended that whenever possible, source animals should be calves up to 6 months old.

For serum: all cellular components must be removed.

For foetal calf serum: great care should be taken to avoid contamination by placenta and foetal fluids. All cellular components must be removed.

Sterilisation of equipment

When sterilisation procedures are used, they should be demonstrated to be capable of inactivating scrapie-like agents. At the present time the following autoclave cycles are recommended:

a) A single cycle at 134ºC (30 psi) for 18 minutes hold time at temperature.

OR

b) Six separate cycles at 134º (30 psi) for 3 minutes hold time at temperature.

5. Sterilisation of product

Standard methods of sterilisation of medical devices are currently thought to be ineffective against scrapie-like agents, but further research continues. It is for this reason that we have adopted the approach of controlling the source of animal materials.

These guidelines may need to be updated in the light of further scientific knowledge.

* Although these guidelines relate to BSE and materials of bovine origin, they should also be considered as generally applicable to material from sheep, goats, deer and other animals susceptible to scrapie-like agents. ¹²

5.76 The questionnaire for medical devices was almost identical to the questionnaire for licensed medicines (see paragraph 5.53 above). It did not, however, include a question on when existing stocks would be exhausted. ¹³

5.77 Follow-up action taken on medical devices and the adequacy of the response is dealt with in Chapter 6.