Purification of monoclonal antibodis using counter current chromatography

This project aims to develop a considerably improved method for the purification of monoclonal antibodies (mAbs) at a preparative, pilot or industrial scale by using a new, emerging technology with a liquid stationary phase. In 2005 the sales of protein therapeutics was estimated to be worth over $50 billion, of which $15 billion was contributed by antibodies. It has been projected that antibodies will show three fold faster growth than other proteins of 21% per annum over the next 5 years to 2010 reaching over $35 billion (Datamonitor 2006). There were 21 protein blockbusters in 2005 versus 6 in 2000 and 7 of the last 11 were antibodies. This is led by the increased interest shown by major pharma companies such as AstraZeneca, GSK and Merck in acquiring new protein drugs. Biologics are predicted to account for 57% of large pharma growth between 2004 and 2010. Since outsourced production is expected to increase from 58% to 69% over the 5 years from 2006, Lonza Biologics, as one of the largest contract manufacturing organisations (CMO) and therefore a predominant force in the process development and production of antibodies to the biologics sector, have a vested interest in production methods for antibodies. It has been noted by governments that the supply of protein therapeutics has a high cost and this has been illustrated by several high profile cases in the British courts where patients have won access to drugs previously denied to them by NICE. As a result there have been agency lead projects to reduce these costs, such as the AIMS project in Europe and the FDA's 21st Century Initiative, which have tried to identify and lower the barriers to entry of new production techniques. This is on top of the industry's efforts to lower such costs internally. At Lonza, the Downstream Processing (DSP) Process Engineering Group has been formed to dedicate resource to investigating such innovative technologies and the use of liquid / liquid extraction by counter current methods is seen as one of the key emerging technologies in this field. MAbs can be produced by cell fermentation and this is the approach adopted by Lonza. The titre in these fermentations is increasing to generally over 5g/L and can be as much as 10g/L. Fermentations can be as large as 20,000L with as much as 200kg mAb coming from a single fermenter. With such masses reaching the purification processes, traditional fixed bed columns can no longer cope with the load placed on them and multiple cycles are required, leading to plant throughput issues. This, together with the limited binding capacity of such columns, means that resin lifespan has been decreased to fewer batches. Combined, these issues have generated an important need to investigate alternatives. This project aims to develop a different method of purification, one that uses a liquid rather than a solid stationary phase. It can therefore operate with the presence of particulate matter direct from the fermentation, and be scaled up to large sizes without pressure problems. The aim is to develop a separation protocol for the preparative-scale purification of monoclonal antibodies using counter-current chromatography (CCC) or centrifugal partition chromatography (CPC). This protocol may use an aqueous two-phase system (ATPS) or an aqueous-organic solvent system. It may also adopt a novel approach such as the use of ionic liquids, the use of affinity ligands within the liquid stationary phase, or the use of a unique continuous counter-current extraction process, approaches that can only be employed when the stationary phase is a fluid. In summary, the goal is to purify mAbs directly from cell fermentations using liquid-liquid technology at a scale up to 200kg per fermenter. To achieve this goal, the research project will be wide ranging, looking at a number of possible options, though always taking full advantage of the fluid nature of the stationary phase.