Understanding the effects of disulfide bond reduction on the structure, function and stability of monoclonal antibodies used in therapy

State of the art biotherapeutics such as monoclonal antibodies (mAbs) contain disulfide bonds. MAbs are manufactured using recombinant cellular expression systems, which can secrete thiol reductase enzymes into the culture medium. These enzymes can reduce disulfide bonds in the antibodies, causing structural and functional changes during manufacturing. Furthermore, diseases such as cancer and inflammatory disorders that are commonly treated by such antibodies also secrete large amounts of reductases, meaning the antibodies can be modified in vivo after administration of the formulated drug.

The aim of this project is to characterise the effects of disulfide bond reduction on the structure, function and stability after formulation of mAbs. A combination of state-of-the-art biophysical analysis by mass spectrometry, and bioassays for function, will elucidate the impact of reduction on both structure and function. This will provide fundamental structural knowledge to improve safety and efficacy of biotherapeutics in general and
will inform routes to improve the manufacturing process and the formulation of antibody-based products. This work aligns to the EPSRC Manufacturing the Future theme, and is a strategic fit to the challenge of developing healthcare for an ageing population.

The project involves expertise and collaboration with the National Institute of Biological Standards and Control (NIBSC), and also LGC, to complement the analytical, structural, computational and formulation expertise of the UCL Department of Biochemical Engineering.

The benefits of the proposed EPSRC Centre for Doctoral Training (CDT) aligned to the EPSRC Centre for Innovative Manufacture of Emergent Macromolecular Therapies will be significant. The CDT will address an acute skills storage of trained manpower, needed to take this industry forward for the benefit of the UK, and ultimately to improve the levels of healthcare provision nationally. This is a radical new opportunity for the industry which suffers from a lack of joined up thinking and hence tends to operate in discrete silos of expertise. The integrated approach offered by the CDT would pay high dividends. UK companies will benefit from access to highly skilled doctorates who will each have benefited from a wide and interdisciplinary research approach created by the CDT. Macromolecular medicines are complex and labile so that bioprocess development times and costs tend to be high due to unforeseen issues that occur during scale-up of the manufacturing process. Currently there is little scope to alter a manufacturing process because the effect of changes cannot be readily predicted. This is compounded by lack of individuals skilled in the methods needed. Our transformative CDT research training agenda will allow for the first time engineers and scientists to create the methods and approaches needed for UK companies to genuinely understand and control directly, for the first time, the quality of output during manufacture, in spite of biological variability. By creating and then testing manufacturing models and methods for whole bioprocesses using the resources of a national EPSRC Centre we shall gain fundamental engineering insights crucial for the more effective direction of acquisitions of experimental data and also the improved design and operation of whole bioprocesses. Manufacturing efficiencies will be raised and waste reduced. Such a vision is consistent with recent efforts by the regulatory authorities, and in particular the Quality by Design (QbD) initiative of the International Committee on Harmonisation (ICH), to develop science-based regulatory submissions for approval to manufacture new biological products. The CDT will create a network to provide a conduit for effective knowledge exchange from the very best academic groups in the UK. A key metric of success will be retention of CDT graduates within the industry where they will be effective in the application of Centre concepts with industrial practice and the adoption of the methods created. Potential patients will benefit as the innovations created by the CDT research will significantly aid reduction in development times of macromolecular medicines, which is particularly crucial for those addressing previously unmet clinical needs and the treatment of severe conditions such as arthritis, cardiovascular disease, viral infections and cancers. By providing industry the capabilities and tools to achieve changes to manufacturing processes we shall open up possibilities for major improvements to processes during production and hence reduce costs to the NHS. The capacity to treat conditions such as rheumatoid arthritis much more effectively in ageing populations is vital but it still poses a problem with respect to stretched NHS budgets. A significantly greater number of drugs will be capable of meeting NICE's thresholds and thus benefit extended patient populations. The UK economy will benefit because the academic research and training offered by the CDT will complement the country's strength in bioscience discovery. Collaboration between bioprocess engineers, process modellers manufacturing experts, regulators and physical scientists will ensure effective knowledge and skills transfer between the science and engineering base and UK industry and the regulating agencies. This will strengthen the UK position in the global healthcare market and attract further R&D investment from global business which recognises the UK as a good place to conduct these activities.