The first spray-dried fibrin medical sealant has been granted FDA approval. The sealant, Raplixa, is intended to control bleeding during surgery. The sealant uses two proteins, thrombin and fibrinogen, which are found in human blood. When the sealant dissolves in blood, a reaction between those proteins causes clotting that then seals small blood vessels, which could not be closed with sutures or cautery. The proteins needed for this adhesive are purified separately and then spray-dried to form powders. Once dried the proteins can be stably stored together, meaning that no mixing is required prior to application. Dry storage also means the sealant tolerates a broad range of temperatures and can be stored without refrigeration. FDA approval was based on a clinical study involving 721 patients where the sealant was used in conjunction with an absorbable gelatin sponge. The combination of sealant and sponge was more effective than a sponge alone in stopping bleeding during vascular, spinal, hepatic and soft tissue surgeries.