Lyophilized peptide

Why are peptides freeze-dried?

Lyophilization removes water from a frozen product under vacuum, letting ice sublime directly to vapor rather than melting first [1]. FDA lists the advantages as enhanced stability of the dry powder, avoiding excessive heating of the product, and rapid, easy dissolution once reconstituted [1]. A 2000 pharmaceutical review calls freeze-drying the most common method for making solid protein pharmaceuticals, done to achieve an acceptable shelf life [2]. The process itself creates freezing and drying stresses that can denature the protein if not controlled [2].

How stable is a lyophilized peptide, and what happens after reconstitution?

Manufacturers set a moisture specification for each freeze-dried product based on its own stability data [1]; there is no single standard shelf life. As one example, FDA's review of MOTS-c cites literature reporting the freeze-dried peptide is stable stored below −20°C, desiccated and protected from light, while the reconstituted solution is recommended to be kept at +4°C for only 2 to 7 days [3]. FDA notes peptides generally can be extremely sensitive to formulation, process and environmental conditions such as pH, heat and concentration, which can cause aggregation or degradation [3].