Single use bioreactors for the clinical production of monoclonal antibodies – a study to analyze the performance of a CHO cell line and the quality of the produced monoclonal antibody

Background In recent years, the use of disposables in the pharmaceutical industry has increased extensively. Disposables can be used in many areas of biopharmaceutical production. The use of disposables not only reduces investment costs, but also requires less manpower to operate, since time consuming change-over procedures are significantly reduced. In addition, disposables enable a high flexibility by reducing unit operation times such as cleaning and sterilization as well as the validation of these procedures [1]. Disposable bioreactors can be subdivided into two main groups, static and dynamic systems. The dynamic systems differ with regard to the power input in stirred, vibromixed or wave-induced systems [2]. Since the power input, the mixing time, the tip speed and the oxygen transfer coefficient may influence the cell culture process and the product quality itself, a thorough characterization of the system used is necessary [3]. SSB (stainless steel bioreactors) and SUB (single use bioreactors) differ in terms of their physical design. Usually, an SSB is equipped with two or three stirrer blades. In contrast, stirred SUBs usually have just one stirrer blade. In addition, the design and the position of the stirrer differ significantly. These distinctions lead to different physical characteristics regarding the power input, mixing time, and tip speed. The SUBs are characterized by a significantly lower power input and tip speed and a significantly higher mixing time. In order to maintain a sufficient oxygen transfer coefficient, the single use bioreactor is equipped with a micro sparger with a pore size of 25 μm. Furthermore, pure oxygen can be used to achieve higher dissolved oxygen concentrations in the cell cultivation medium. This study describes the influence of these technical differences on the performance of a CHO cell line and the product quality of a monoclonal antibody.