Dissolvable Films: Dissolvable Films for Flexible Product Format in Drug Delivery

For pediatric and geriatric patients, fast-dissolving drug-delivery systems provide an easier way to take medications and vitamins. Oral thin films have evolved to provide systemic delivery of active pharmaceutical ingredients for over-the-counter and soon, prescription drugs. The authors review the practical benefits of dissolvable films, their manufacture, and their market potential.
Apr 01, 2008


Authors
Fast-dissolving drug-delivery systems were first developed in the late 1970s as an alternative to tablets, capsules, and syrups for pediatric and geriatric patients who experience difficulties swallowing traditional oral solid-dosage forms (1). In response to this need, a variety of orally disintegrating tablet (ODT) formats were commercialized. Most ODT products were formulated to dissolve in less than one minute when exposed to saliva to form a solution that could then be more easily swallowed.

Dissolvable oral thin films (OTFs) evolved over the past few years from the confection and oral care markets in the form of breath strips and became a novel and widely accepted form by consumers for delivering vitamins and personal care products. Companies with experience in the formulation of polymer coatings containing active pharmaceutical ingredients (APIs) for transdermal drug delivery capitalized on the opportunity to transition this technology to OTF formats. Today, OTFs are a proven and accepted technology for the systemic delivery of APIs for over-the-counter (OTC) medications and are in the early- to mid-development stages for prescription drugs.

This article provides insight into the functionality and benefits of dissolvable films and reviews the current product landscape and market potential. The authors also explain how thin films are formulated and manufactured, and discuss potential future applications.

Functionality and benefits

Pharmaceutical companies and consumers alike have embraced OTFs as a practical and accepted alternative to traditional OTC medicine forms such as liquids, tablets, and capsules. OTFs offer fast, accurate dosing in a safe, efficacious format that is convenient and portable, without the need for water or measuring devices (2). OTFs are typically the size of a postage stamp and disintegrate on a patient's tongue in a matter of seconds for the rapid release of one or more APIs.

The formulation of dissolvable films is customarily facilitated through aqueous polymer matrices that span a wide molecular weight (MW) range, thereby providing flexibility to achieve certain physical properties. With the selection of appropriate polymer excipients, these properties can be tailored to meet specific API-loading needs and dissolution rates.


Table I
To date, the commercial launch of OTFs is primarily in OTC products addressing therapeutic categories such as cough/cold, sore throat, and antacid/gas relief as well as a number of nutritional supplement applications (2) (see Table I). In compliance with the appropriate monographs, current products deliver a specified API dose that is immediately released and ingested. Some drug forms are more easily used in OTFs than others (soluble versus nonsoluble), but we can expect API concentrations to increase as new OTF formulations are developed.


Strategic therapeutic categories for oral thin films
The capabilities of the base technology to create dissolvable films continue to evolve. For example, a common misconception of the OTF format is that it is limited with regard to the loading capacity of APIs. Some researchers reference a limit of 30 mg of API content as the maximum concentration. A more accurate statement would be that OTFs have the capability to load APIs up to 50% of the unit dose mass, as demonstrated by Novartis Consumer Health's Gas-X thin film, which contains 62.5 mg of simethicone per dose (3).