Purified Bulk Harvest
Final bulk, drug substance or bulk drug substance are used to describe the bulk drug after all of the downstream purification has occurred and the product has been vialed. This substance usually has excipients added such as buffers or other materials. The drug substance must be characterized to demonstrate that the drug has been manufactured to meet specifications and these are outlined here.
The regulations for General Biological Products Standards under 21 CFR Part 610 provide that each lot must be tested for potency, general safety, sterility, endotoxin, purity and identity.
Product potency testing can be carried out by in vivo or in vitro assays or through “matrix testing” of a combination of both. These assays are required to show the material is active and to provide a measure of the specific activity of the product.
A number of these tests will be product specific and the appropriate guidelines should be consulted. For example, a number of contaminants from the host cells such as proteins or DNA or materials used to purify the virus such as benzonase will be measured. TEM and titration for ratio of infectious to non infectious gene therapy vectors is often required.
Contact our scientists to discuss your testing requirements.