The Biopharmaceutics Classification System: subclasses for in vivo predictive dissolution (IPD) methodology and IVIVC

Advancing Product Quality: a Summary of the Inaugural FDA/PQRI Conference

On September 16 and 17, 2014, the Food and Drug Administration (FDA) and Product Quality Research Institute (PQRI) inaugurated their Conference on Evolving Product Quality. The Conference is conceived as an annual forum in which scientists from regulatory agencies, industry, and academia may exchange viewpoints and work together to advance pharmaceutical quality. This Conference Summary Report highlights key topics of this conference, including (1) risk-based approaches to pharmaceutical development, manufacturing, regulatory assessment, and post-approval changes; (2) FDA-proposed quality metrics for products, facilities, and quality management systems; (3) performance-based quality assessment and clinically relevant specifications; (4) recent developments and implementation of continuous manufacturing processes, question-based review, and European Medicines Agency (EMA)-FDA pilot for Quality-by-Design (QbD) applications; and (5) breakthrough therapies, biosimilars, and international harmonization, focusing on ICH M7 and Q3D guidelines. The second FDA/PQRI conference on advancing product quality is planned for October 5-7, 2015.

Interspecies prediction of oral pharmacokinetics of different lacidipine formulations from dogs to human: physiologically based pharmacokinetic modelling combined with biorelevant dissolution

PBPK modelling combined with biorelevant dissolution to quantitatively predict dog PK of different lacidipine formulations, and to extrapolate to human.

Quantification of gastrointestinal liquid volumes and distribution following a 240 mL dose of water in the fasted state

The rate and extent of drug dissolution and absorption from solid oral dosage forms is highly dependent upon the volumes and distribution of gastric and small intestinal water. However, little is known about the time courses and distribution of water volumes in vivo in an undisturbed gut. Previous imaging studies offered a snapshot of water distribution in fasted humans and showed that water in the small intestine is distributed in small pockets. This study aimed to quantify the volume and number of water pockets in the upper gut of fasted healthy humans following ingestion of a glass of water (240 mL, as recommended for bioavailability/bioequivalence (BA/BE) studies), using recently validated noninvasive magnetic resonance imaging (MRI) methods. Twelve healthy volunteers underwent upper and lower abdominal MRI scans before drinking 240 mL (8 fluid ounces) of water. After ingesting the water, they were scanned at intervals for 2 h. The drink volume, inclusion criteria, and fasting conditions matched the international standards for BA/BE testing in healthy volunteers. The images were processed for gastric and intestinal total water volumes and for the number and volume of separate intestinal water pockets larger than 0.5 mL. The fasted stomach contained 35 ± 7 mL (mean ± SEM) of resting water. Upon drinking, the gastric fluid rose to 242 ± 9 mL. The gastric water volume declined rapidly after that with a half emptying time (T50%) of 13 ± 1 min. The mean gastric volume returned back to baseline 45 min after the drink. The fasted small bowel contained a total volume of 43 ± 14 mL of resting water. Twelve minutes after ingestion of water, small bowel water content rose to a maximum value of 94 ± 24 mL contained within 15 ± 2 pockets of 6 ± 2 mL each. At 45 min, when the glass of water had emptied completely from the stomach, total intestinal water volume was 77 ± 15 mL distributed into 16 ± 3 pockets of 5 ± 1 mL each. MRI provided unprecedented insights into the time course, number, volume, and location of water pockets in the stomach and small intestine under conditions that represent standard BA/BE studies using validated techniques. These data add to our current understanding of gastrointestinal physiology and will help improve physiological relevance of in vitro testing methods and in silico transport analyses for prediction of bioperformance of oral solid dosage forms, particularly for low solubility Biopharmaceutics Classification System (BCS) Class 2 and Class 4 compounds.

G.L. Amidon, H. Lennernas, V.P. Shah, and J.R. Crison. A theoretical basis for a biopharmaceutic drug classification: the correlation of in vitro drug product dissolution and in vivo bioavailability, Pharm Res 12, 413-420, 1995--backstory of BCS

The Biopharmaceutics Classification System (BCS) has become widely accepted today in the academic, industrial, and regulatory world. While the initial application of the BCS was to regulatory science bioequivalence (BE) issues and related implications, it has come to be utilized widely by the pharmaceutical industry in drug discovery and development as well. This brief manuscript will relate the story of the BCS development. While much of the ground work for the BCS goes back to the pharmacokinetic and drug absorption research by Gordon Amidon (GLA) in the 1970s and 1980s, the realization of the need for a classification or categorization of drug and drug products for setting dissolution standards became apparent to GLA during his 1990-1991 sabbatical year at the FDA. Initiated at the invitation of the then CEDR director, Dr. Carl Peck, to become a visiting scientist at the FDA, the goal was to promote regulatory research at the FDA, in my case, in biopharmaceutics, and to develop a science-based system to simplify regulatory requirements.