Aseptic Vial Filling

Ideally, injectable drugs are sterilized in their final containers by a foolproof method like autoclaving. This is not possible for biologicals like monoclonal antibodies (mAbs), so they must be manufactured aseptically, sterilized by filtration and then filled into sterile vials or ampoules. The final filling procedure is the most critical aseptic process and should be done in a very clean environment. Automatic machines are used for large production processes and eliminate the risk of contamination associated with manual processes. However, preparing material for early clinical trials can be problematic because the batch size is normally too small for a filling machine (e.g., 500-1000 vials). Normal practice is to fill this number of vials by hand, but the vials and closures have to be washed, depyrogenated (by baking in an oven), and sterilized, and the filling has to be carried out in a very strictly controlled environment, because the vials are open throughout the process and are only stoppered and sealed in a second step.