Thursday, 29 September 2022
Europe - Rome

The worldwide demand for biotechnologically produced proteins is growing significantly, driven by recombinant monoclonal antibodies (mAbs), whose overall sale is expected to grow up to $125 billion by 2020, with more than 70 mAbs products on the market. To satisfy this request, production processes have been optimized for higher concentration by significant progress in cell culture media and recombinant technologies. However, this development created a bottleneck in the following downstream processing (DSP), which currently relies on complex, inefficient and expensive separation stages, traditionally operated in batch-mode and primarily based on chromatography. With the therapeutic potential for species of the complexity of mAbs established, the challenge now moves to rise access to such molecules through being able to isolate and purify them at target scale and to reduce manufacturing costs.

Preparative crystallization is a cost effective and easily scalable purification technique for the recovery of target products directly from clarified fermentation broths. Crystallization has thus immense potential to be used for separation and formulation in mAbs manufacture as it offers the option to remove many of the DSP steps.





Furthermore, the solid-crystalline state affords for higher product activity, stability and a sustained release capability (bioavailability) relative to liquid-based formulations or amorphous freeze-dried solids.

Nevertheless, crystallization of protein is intrinsically more difficult and uncertain than for small molecules, particularly from complex mixtures, due to their large molecular weights, structural complexities and flexibility, and the presence of impurities. Therefore, up to now, crystallization has been prevented to be widely used in the industrial purification of biopharmaceuticals.




On this premise, the targeted scientific breakthrough of AMECRYS is to definitively unlock the industrial application of protein crystallization in biopharmaceutics by developing an innovative, continuous, downstream processing for mAbs purification based on the Template-Assisted Membrane Crystallizer as key-unit, leading to the complete replacement of the expensive and cumbersome conventional multi-step batch chromatography-based platform. The new process will be tested on molecules representative of important therapeutic formats, such as anti-cancer antibody molecules. 


Membrane crystallization is a radically new separation technology based on the use of macroporous hydrophobic membranes to extract solvent in vapor phase from the feed solution. The technological concept differs from a traditional membrane filtration process: under a partial porizes at the feed/membrane interface, diffuses through the macropores and condenses at the extractant side. Unique advantages with respect to conventional crystallizers are pressure gradient established according to the principles of vapour-liquid equilibrium, the solvent vap


Figure 11

  • accurate control of the trans-membrane flux of solvent that drives the system through tailored and homogeneous supersaturation pathways within the Metastable Zone, thus improving product crystallization in terms of particle shape and size distribution, eventual polymorph selection, and impurity control;


  • chemical-physical properties (surface energy/contact angle) and topography (roughness/porosity/pore size & size distribution) of the membrane represent novel tools to modulate the extent of the Gibbs free energy barrier to heterogeneous nucleation and, ultimately, to control crystallization kinetics.




 The additional innovative idea of AMECRYS being applied is template-assisted crystallization of mAbs by 3D-nanotemplates, used as selective molecular recognitors in multicomponent solutions to enable crystallization-reluctant molecules like proteins to effectively interact. Moreover, the success of AMECRYS will substantially contribute to the paradigm shift from conventional batch to innovative continuous manufacturing in the pharmaceutical industry.


In the long-term vision of the AMECRYS’ Consortium, conscious of the recognition of membranes in several industrial sectors, continuous template-assisted membrane crystallization has the potential to revolutionize the DSP manufacturing platform in biopharma, leading to drastic reduction of raw materials consumption and wastes generation, providing distributed, miniaturized and modular manufacturing systems allocable at the point of use, opening new market opportunities such as “on demand” personalized medicines, localized productive cycles also in remote areas, low volume drugs production for niche and orphan indications. In perspective, unique features of template-assisted membrane crystallization might open the way to revolutionary technological solutions in biopharmaceutical production.