In order to develop gene therapy treatments for humans, vectors must be produced in very large quantities. This process is quite complex and requires extreme safety precautions.
To produce the vectors, specially developed cell factories are used, which are capable of producing gene-drugs if the proper raw materials are provided.
- First step: the factory-cells are grown in liquid media in culture bottles or in large vats which at present (year 2012) can contain up to 200 liters.
- Second step: The cells multiply in culture medium and various parameters are verified during this stage. It takes about two weeks to produce a sufficient quantity of cells.
- Third step: the real starting point. The cells are given the instructions to produce the bio-medicine. They are given a program in the form of a DNA fragment or architect-virus, which gives them all the information necessary to construct the bio-medicine. This phase takes between three and six days.
- Fourth step: Now the scientists only have to recover the bio-medicines—this is the purification step. This takes place on a chromatographic column which retains the bio-medicines and lets the cell debris wash out. Then a liquid is added which detaches the bio-medicine molecules. At this point 4 liters of product is recovered for 200 liters of culture. Once concentrated, this is reduced to 200 ml, which is stored in 2 ml ampoules. This operation takes about 2 days.
- Fifth step: The ampoules of product undergo analysis by the quality control department, which has also permanently controlled each component at each production step.
The result is a bio-medicine which conforms to regulatory requirements, and which will be administered to patients in the framework of clinical trials.