Tastemasking of solid dosage forms and liquid drugs is a challenge for pharmaceutical manufacturers. Most APIs are unpleasant
or harsh tasting, which can lead to patient noncompliance. This challenge affects all age groups, but is specifically problematic
for pediatric patients. Implementing tastemasking programs into the drug-manufacturing process is crucial to avoid losses
due to noncompliance. Pharmaceutical manufacturers are faced with challenges in life-cycle management, cost control, global
regulations, and patent protection. In a Q&A, Pharmaceutical Technology examines excipient selection and functionality in tastemasking applications.
In a webcast, Pharmaceutical Technology examined formulation development in product life-cycle management, including specialized formulations such as pediatric formulations,
and related technical issues in excipient selection and functionality, including tastemasking and moisture protection, to
develop an orally palatable product (1). Participating in the webcast were: Avinash Thombre, PhD, research fellow, pharmaceutical
sciences with Pfizer Global Research and Development, who discussed life-cycle management and new dosage-form options; Karen
C. Thompson, PhD, distinguished senior investigator, pharmaceutical sciences at Merck & Co., who discussed insight into pediatric
formulations and related dosage forms; and Nigel Langley, PhD, MBA, head of North American technical sales, Pharma Ingredients
& Services, BASF, who discussed novel tastemasking excipient solutions. For a perspective on excipient selection and functionality
in tastemasking applications, Patricia Van Arnum, executive editor of Pharmaceutical Technology and moderator of the webcast further discussed these issues with BASF's Langley.
The dialogue was initiated following the launch by BASF of an excipient, Kollicoat Smartseal 30 D, an aqueous dispersion of
a film-forming polymer with tastemasking and moisture-barrier applications for solid dosage forms. The product is a new coating
polymer and is supplied as a 30% dispersion in water. From a product-characteristic perspective, the excipient is highly impermeable
to water vapor, which helps preserve the potency of sensitive active ingredients. The polymer is stable in saliva and specifically
soluble in gastric juice. These properties allow for effective protection from unpleasant taste in the patient's mouth and
rapid release and onset of active-ingredient action in the stomach.
In October 2011, BASF and Colorcon formed a collaboration for developing future film-coating systems using BASF's Kollicoat
Smartseal 30 D and a new Colorcon preformulated additive. Colorcon developed the preformulated additive system for use with
Kollicoat Smartseal 30 D to enable efficient preparation and application of this polymer in tastemasking applications. The
preformulated additive lowers the number of materials to be dispensed by 50% and reduces the preparation time by almost 40%,
according to an Oct. 21, 2011, Colorcon press release.
Excipient properties in tastemasking
What characteristics does an excipient need to have to provide tastemasking?
The material has to be stable at pH 6.8 to 7.2, so you do not get any of the bitter drug released in the saliva. In addition,
the drug has to, upon entering the stomach, be rapidly released at a low pH. We are basically looking for a reversed enteric
polymer to provide that functionality. With respect to Kollicoat Smartseal 30 D, specifically, the polymer is insoluble at
basic and neutral pH value and has very low vapor permeability, which is characterized by the structure—primarily, the two
ethyl groups that are attached to the nitrogen moiety and the polymer itself is the methyl methacrylate diethylaminoethyl
methacrylate copolymer. It is very insoluble at pH neutral values as well as basic pH. It forms a salt at pH values below
5.5, so the polymer dissolves quickly in the stomach releasing the drug.