Thin Films in Drug Delivery

November 30, 2012 Greg Rosenberg

Oral thin film (OTF) drug delivery systems are generally designed to dissolve in the mouth, cheek, under the tongue or in the intestinal tract.  Each intended use can pose a unique challenge for thin film producers.  While attention must be paid to film thickness, simply producing a good quality thin film isn’t enough.  When the drug to be administered is compounded in liquid form and precise dosing is critical, rheology (flow properties) takes center stage.

Numerous production methods can address critical OTF requirements.  Gravure systems offer high quality results when working with low-viscosity materials, while extrusion systems are well-suited to high-viscosity materials.  Modern slot-die systems, however, offer the broadest viscosity range, generally from 10-30,000 centipoise.  Slot-dies are also well-suited to OTF production since slot-die technology is based on precise, fixed material metering. This ensures consistent, accurate drug dosage in production and practically eliminates material waste - a critical regulatory benefit when incorporating a prescription drug into an OTF delivery system.

Slot-die systems also allow for mix changes at the die inlet while remaining closed to the environment to eliminate contamination.

Thin film drug delivery systems hold enormous promise for consumers. There is perhaps no easier or more accurate way to self-administer over-the-counter and prescription medicines.  Thin film technology also bodes well for the pharmaceutical industry, since dosage can be strictly controlled at nearly every phase of production by changing liquid drug concentrations, film thickness and slitting parameters.  Partnering with the right thin film producer and taking advantage of the proper production environment will yield significant results for drug manufacturers.