Extrusion

Using hot melt extrusion, we have both the facilities and expertise to develop tailor made controlled-release delivery systems such as vaginal rings and implants.

Hot melt extrusion is the process of melting a polymer at elevated temperatures and forcing it through a die in order to produce a strand with a fixed cross-sectional profile in a continuous manner. Over the past decades hot melt extrusion has emerged as a suitable technology for the production of pharmaceutical drug delivery systems such as vaginal rings, implants, and transdermal films.

In pharmaceutical manufacturing mainly two different types of extruders are used. For mixing operations generally twin-screw extruders are used and the obtained mixture is in most cases an intermediate product required for further processing. Further processing of the intermediate mixture can take place on a co-extruder, which is a machine used for the manufacture of the actual delivery system, for example an implant. A co-extruder essentially is a set-up of two or more extruders connected to the same extruder die. Using multiple extruders connected to each other make it possible to manufacture more complex delivery systems in an efficient and robust manner.

Twin-screw extruders are versatile mixing machines with co-rotating screws, which can be adapted to specific processing needs. Typically, twin-screw extruders are used for the manufacture of a homogeneous intermediate, which is used in the further manufacture of the final delivery system. For this purpose, the hot molten strands exiting the extruder die are cooled in-line and cut to small pellets using a strand granulator.

The purpose of a co-extrusion line is the manufacturer of delivery systems with more complex geometry, for example an implant comprising of a drug loaded core which is encompassed by a thin rate limiting sheath. The melt streams exiting the individual extruders are subsequently combined to form the desired core-sheath geometry in the extruder die.  The technique is very versatile as composition and geometry of each layer can be adjusted to achieve the desired release of one or more drugs. Moreover, the manufacturing process is continuous and very suitable for robust industrial-scale manufacturing of delivery systems.