Alzheimer’s An Infectious Disease
While many of us may think of medical devices as complex combinations of metals, plastics, and electronics, many medical devices also contain animal-derived materials. Examples include bovine materials used to make heart valves, sutures, tear duct plugs, and dental implants. These animal-derived materials are not without risk. They may carry transmissible spongiform encephalopathies (TSEs) – including mad cow disease – when improperly collected, stored, or manufactured. The risks are compounded by the fact that currently, there are no treatments for TSE diseases and no way of screening for them in a live person or animal.
To address the risks of TSEs, FDA recently released a draft guidance entitled “Medical Devices Containing Materials Derived from Animal Sources (Except for In Vitro Diagnostic Devices).” This guidance is meant to replace an earlier 1998 guidance that focused on the risk of transmitting bovine spongiform encephalopathy (BSE), commonly known as Mad Cow Disease. While BSE is still included, FDA’s latest guidance also contains the risks of other forms of TSEs, such as scrapie (found in sheep), chronic waste disease (found in deer), and Creutzfeldt-Jakob Disease (found in humans). The guidance is applicable to all medical devices that contain or are exposed to animal-derived materials (e.g., bovine, ovine, porcine, avian materials), with the exception of in vitro diagnostic devices.
FDA further recommends that companies maintain test results for each lot of material at the manufacturing facility. Methods for maintaining the records as well as a description of the tests performed should be provided in regulatory submissions. Moreover, companies should analyze the source of their animal-derived materials, as non-TSE-transmitting animals may be slaughtered in facilities that also process TSE-transmitting animals.
Although FDA’s most recent guidance is a draft, companies using animal-derived material should take note of FDA’s expanded view of not only which animal materials contain risk (i.e., no longer limited to bovine material), but also which steps are appropriate to ensure the safety of those materials. Moreover, companies should remain vigilant about future developments. To date, no test exists that can reliably identify TSE-containing materials. However, should one be developed, “FDA will consider revisiting this guidance as appropriate and recommending that such a test be introduced into the standard operating procedures for bovine tissue collection and processing.”