There are some important factors to consider in the development, production, transport, and storage of ADCs. Proteins, including antibodies, must be stored carefully to prevent their decomposition. However, if ADCs undergo repeated freeze-thaw cycles they are susceptible to aggregation, which can affect their efficacy, so they are often stored at 2–8°C. To enable longer-term storage, ADCs are generally subjected to freeze-drying, which is also known as lyophilization. Most of the currently marketed ADCs are lyophilized products. However, the rate of freezing is difficult to control when using the conventional, static freezers employed for lyophilization. Uncontrolled freezing can also cause proteins to aggregate, leading to their denaturation.
Controlled freezing, therefore, is an increasingly important topic in ADC production. Plate-based freezer technology allows the precise control of temperature decreases, with setpoints that can be introduced according to a product’s characteristics, allowing faster or slower freezing, as required. With plate-freezers, such as Single Use Support’s RoSS.pFTU system, protein degradation is prevented from occurring during the freezing process by ensuring controlled, rapid, and uniform freezing. A consistently high freezing velocity leads to a significantly lower level of cryoconcentration (the concentration of proteins in the solid or liquid parts of a partially frozen mixture), denaturation, and formation of aggregates. It also enables better preservation of the original characteristics of the substance being frozen. RoSS.pFTU is a controlled hybrid freezer which can be used for both in one platform, to freeze and thaw single-use bags with plates and bottles with blast freezing technology.