Showing posts with label TSE. Show all posts
Showing posts with label TSE. Show all posts

Friday, December 18, 2009

Got Animal-Derived Materials? Part 3

By Dr. Ray Nims

The assessment of viral and transmissible spongiform encephalopathy (TSE) risk for animal-derived materials (ADM) used in the manufacture of biologics, which we have described in previous blogs, is just one component of an overall ADM program that should be in place at each organization producing biologics.



A formal ADM program at a biologics manufacturer ideally should be driven by an overriding SOP or policy document. This should address the procedures in place for minimizing the use of ADM, for procuring ADM with a view to minimizing viral and TSE risk, and for assessing the viral and TSE risk associated with the ADM that are used. There are specific sourcing requirements for ADM that are intended to minimize TSE risk (EMEA/410/01 Rev. 2 October 2003), and these must be followed or justification provided if deviated from. The evaluation of ADM for the presence of viruses of concern is addressed in the Code of Federal Regulations, Title 9 Part 113.53. ADM viral and TSE risk assessments should be conducted according to a formalized procedure by teams of individuals with education, training, and/or experience appropriate for these tasks. The composition of the risk assessment teams and the qualifications of their members should be described in revisable controlled documents. The risk assessments themselves should be recorded in controlled documents which may revised as new information becomes available from the ADM suppliers. The ADM information that is used as part of the risk assessment process should be archived in a manner tying it to the risk assessment itself.


The existence of a formalized ADM program, qualified risk assessment teams, as well as reports documenting the individual ADM risk assessments may be the subject of regulatory scrutiny during periodic inspections or inspections tied to a new product application. This is especially likely if the product is intended for global distribution, as these ADM issues are specifically mentioned in EP (Chapter 5.1.7) and EMEA (EMEA/410/01 Rev. 2 October 2003) guidance.

Thursday, October 29, 2009

Got animal-derived materials? Part 2

By Ray Nims

As part of a formal animal-derived materials program, biopharma companies must assess the viral and TSE risk associated with materials derived from animals or which have been in contact with animal-derived materials at some point. We have addressed the viral risk within a previous blog installment. Now let’s consider the TSE risk.

TSEs (transmissible spongiform encephalopathies) are fatal diseases believed to result from exposure of a few animal species (including various ruminants, cervids, ungulates, cats, minks, and humans) to “infectious” prion proteins. The infectious proteins (PrPSc) are capable of interacting with and altering the normal prion proteins (PrPc) within the brain and spinal cord, changing the normal proteins to the abnormal form. Since humans have contracted prion disease as a result of consuming tissues from cattle with bovine spongiform encephalopathy (mad cow disease), there is concern about the use of bovine materials and materials from other “relevant species” in the manufacture of biopharmaceuticals.

The EMEA has provided a guidance document (EMEA/410/01 Rev. 2 October 2003; http://www.emea.europa.eu/pdfs/human/bwp/TSE%20NFG%20410-rev2.pdf) describing the requirements for the use of animal-derived materials from relevant animal species (cattle, sheep, goats, and other animals which are naturally susceptible to TSEs but not including humans or non-human primates) in the manufacture of medicinal or veterinary products. The guidance applies to active substances, excipients and adjuvants, raw and starting materials and reagents, and materials which come into contact with products or equipment used to make product. The major point of the guidance is that TSE risk can be minimized, but in many cases not entirely eliminated. Where TSE risk cannot be avoided through elimination of animal-derived materials completely, the guidance provides principles for the minimization of TSE risk which include: the use of low-risk (non-relevant) animal species, the geographical sourcing of relevant species from low-risk regions, the use of low-risk tissues, the use of appropriate slaughter techniques to reduce potential for contamination of low-risk tissues with high-risk tissues, the appropriate oversight of manufacture of the animal products through Quality Assurance and self and external auditing and Quality Control testing, and the implementation of process designs to remove or inactivate the abnormal prion proteins.

Biopharma companies using animal-derived materials are instructed to perform risk assessments on those materials, which take into account the factors described above. The risk assessments must be completed as part of a formalized animal-derived materials program, documented procedurally and executed by staff that are experienced and trained to conduct such assessments. EMEA inspectors will expect to see this formal program in place. Risk assessments for individual raw materials may then be rolled up into a risk assessment for the biopharma product. The rolled up risk assessment may also consider manufacturing steps at the biopharma which may remove or inactivate the abnormal prion proteins, though these, if cited, may need to be validated. Finally, it is expected that companies will conduct a benefit/risk evaluation to assure that any benefits realized by the patient taking the product will outweigh and justify the risk associated with the use of materials derived from relevant animal species.