In vivo investigation of twin-screw extruded lipid implants for vaccine delivery

Composites of fatty acids and ceramic powders are versatile biomaterials for personalized implants and controlled release of pharmaceuticals

“…It may be possible to formulate similar lipid/ceramic matrices with other solid lipids found naturally in the human body. Implantable matrices based on cholesterol, phospholipids and triglycerides have been extensively and successfully explored for sustained release of pharmaceuticals [32][33][34], but as far as we know not for structurally loaded or larger implants. These studies with pharmaceutical release devices support our findings that solid lipid implants are biocompatible and further indicate that the resorption rates and drug release rates can be controlled by varying the lipid composition.…”

Vaccine implants: current status and recent advancements

“…The manufacture of the implants was further developed with twin-screw extruded lipid implants being made (Figure 1). The implants could be produced with uniform density and shape using a one-step extrusion procedure [15]. The twin-screw extruded lipid implants consisting of cholesterol, soybean lecithin and Dynasan 114, and loaded with OVA and Quil A, generated improved cellular and humoral response in mice after subcutaneous implantation.…”

“…A seminal contribution to the field of vaccine implants was made by Mooney and collaborators who developed a disruptive technology using tablet-shaped PLGA scaffolds containing granulocyte-macrophage Reproduced under CC BY 4.0 license [16] and with permission from [15,28].…”

“…(C) Cyto-exclusive implant design consisting of a polyanhydride vaccine depot (rod) enclosed in an ultra-high molecular mass polyethylene implant with a hydrophilic poly(vinylidene fluoride) (PVDF) membrane cap. PVDF pores (0.65 mm) allows flow of proteins into and out of the implant, while excluding leukocytes.Reproduced under CC BY 4.0 license[16] and with permission from[15,28].…”

Impact of implant composition of twin-screw extruded lipid implants on the release behavior

“…64 The use of synthetic polymer matrix materials has the additional problem that during 65 manufacture irreversible changes in structure and activity of proteins can be induced 66 by heating, high shear forces, exposure to organic solvents and increased osmotic 67 pressure (Vogelhuber, Magni, Mouro, et al, 2003). 68 An interesting alternative is to utilize lipid implants as parenteral controlled delivery Recently, we reported that lipid implants for vaccine delivery can be prepared by 88 twin-screw extrusion (M. P. Even et al, 2014). They were solid, easy to handle and 89 showed good mechanical properties.…”