Methods for freeze-drying and rehydrating biologics

The present disclosure pertains to lyophilized compositions comprising elements of the culture medium of protozoa and at least one cryoprotectant as well as processes for obtaining lyophilized compositions containing freeze-dried protozoa of an intracellular nature and being devoid of protozoal host cells, the composition containing a moisture content of less than 12% by weight and being capable of reconstitution to restore said protozoa to viable and infectious states. Said lyophilised compositions comprise a culture medium selected from: DMEM, RPMI or PBS; a cryoprotectant selected DMSO, a monosaccharide, a disaccharide, an oligosaccharide, a polysaccharide or a mixture thereof; and further comprising one or more of: an osmoprotectant which is ectoine, an anti-oxidant selected from GSH, EGCG, ascorbic acid or a mixture thereof, and/or another additive which is proline.