Over the last 70 years many cases of in vivo failure of enteric coated (EC) formulations have been reported. EC products present a marked slower dissolution in physiologically relevant buffer which seems to be the cause for the observed in vivo failures. There is a hidden performance problem with EC products. Upon reaching the intestinal lumen, the dosage form is exposed to an environment buffered by bicarbonate at much lower molarities than those applied in compendial methods with phosphate buffer. Thus, this presentation aims to raise awareness of this matter and to elucidate the complex interaction between bicarbonate buffer and enteric coating polymers.
An in vitro study investigating the performance of drug products from the market in both compendial buffer and physiologically relevant bicarbonate buffer will be covered. The results clearly indicate that the in vitro performance of EC products is highly dependent on the ionic composition and molarity of the medium. In fact, this seems to impact the coat opening more than bulk pH. Consequently, the generally accepted concept of a dissolution pH threshold for enteric coating polymers is questionable in bicarbonate buffer. Hence, the physiological aspect of bicarbonate buffer should be taken into account during the formulation development process to avoid possible failures due to insufficient drug release. Analysis of possible approaches for a better quality control method for EC products will foster an environment for rich discussion.
- Raise awareness of the unpredictable in vivo performance of enteric coated formulations
- Elucidate the complex interaction between bicarbonate buffer and enteric coating polymers
- Describe an in vitro study investigating the performance of drug products in both compendial buffer and physiologically relevant bicarbonate buffer
- Explore possible approaches for a better quality control method for EC products
Daniela obtained her BSc in pharmacy from the University of Sao Paulo in 2017. During her undergraduate studies she was a recipient of the Science Without Borders scholarship for an exchange program at the University of Toledo, OH (2014 – 2015). During the year of 2016 she worked at Johnson & Johnson in the regulatory affairs division. Daniela was recipient of the University of Alberta Research Experience award in 2017. In 2018 she joined the PhD program at Faculty of Pharmacy and Pharmaceutical Sciences at the University of Alberta under the supervision of Dr. Raimar Loebenberg. Daniela has clear understanding of the underlying sciences responsible for the complexity of oral drug absorption and has authored and co-authored many publications in great scientific journals. Daniela’s main scientific interest is focused on formulation, delivery and quality in the drug development process.