Challenges for the pharmaceutical technical development of protein coformulations

Objectives This review discusses challenges to stability, analytics and manufacturing of protein coformulations. Furthermore, general considerations to be taken into account for the pharmaceutical development of coformulated protein drug products are highlighted. Key findings Coformulation of two or more active substances in one single dosage form has recently seen increasing use offering several advantages, such as increased efficacy and/or the overall reduction of adverse event incidents in patients. Most marketed coformulated drug products are composed of small molecules. As proteins are not only comparatively large but also complex molecules, the maintenance of their physicochemical integrity within a formulation throughout pharmaceutical processing, storage, transport, handling and patient administration to ensure proper pharmacokinetics and pharmacodynamics in vivo already represents various challenges for single-entity products. Thus, nowadays, only sparse biologics-based coformulations can be found, as additional complexity during development is given for these products. Summary The complexity of the dosage form and the protein molecules results into additional challenges to formulation, manufacture, storage, transport, handling and patient administration, stability and analytics during the pharmaceutical development of protein coformulations. Various points have to be considered during different stages of development in order to obtain a safe and efficacious product.