Design and Analysis of Bridging Studies

"In recent years, the variations of pharmaceutical products in efficacy and safety among different geographic regions due to ethic factors is a matter of great concern for sponsors as well as for regulatory authorities. However, the key issues lie on when and how to address the geographic variations of efficacy and safety for the product development. To address this issue, a general framework has been provided by the ICH E5 (1998) in a document titled "Ethnic Factors in the Acceptability of Foreign Clinical Data" for evaluation of the impact of ethnic factors on the efficacy, safety, dosage, and dose regimen. The ICH E5 guideline provides regulatory strategies for minimizing duplication of clinical data and requirements for bridging evidence to extrapolate foreign clinical data to a new region. More specifically, the ICH E5 guideline suggests that a bridging study should be conducted in the new region to provide pharmacodynamic or clinical data on efficacy, safety, dosage, and dose regimen to allow extrapolation of the foreign clinical data to the population of the new region. However, a bridging study may require significant development resources and also delay availability of the test medical product to the needed patients in the new region. To accelerate the development process and shorten approval time, the design of multiregional trials incorporates subjects from many countries around the world under the same protocol. After showing the overall efficacy of a drug in all global regions, one can also simultaneously evaluate the possibility of applying the overall trial results to all regions and subsequently support drug registration in each of them"--Provided by publisher.

Jen-pei Liu is a professor in the Division of Biometry, Department of Agronomy, and Institute of Epidemiology and Preventative Medicine at National Taiwan University. He is also an adjunct investigator in the Institute of Population Health Sciences at the National Health Research Institutes in Taiwan. A fellow of the ASA, Dr. Liu is an associate editor of the Journal of Biopharmaceutical Statistics and an editor of the Chapman & Hall/CRC Biostatistics Series. He has authored ten books, over 120 peer-reviewed research articles, and over 40 book chapters. His research interests include statistical methodology in bioequivalence evaluation, clinical trials, equivalence and noninferiority testing, bridging testing, statistical quality control in biopharmaceutical products, diagnostic testing, statistical QA/QC for biochip diagnostic products, and evaluation of substantial equivalence in GMO crops and food.

Shein-Chung Chow is a professor in the Department of Biostatistics and Bioinformatics at Duke University School of Medicine. Dr. Chow is also a professor of clinical sciences at Duke–National University of Singapore Graduate Medical School. He is the editor-in-chief of the Journal of Biopharmaceutical Statistics and editor-in-chief of the Chapman & Hall/CRC Biostatistics Series. He has authored or co-authored over 200 papers and 19 books, including Adaptive Design Methods in Clinical Trials, Second Edition, Handbook of Adaptive Designs in Pharmaceutical and Clinical Development, and Controversial Statistical Issues in Clinical Trials. A fellow of the ASA and member of the ISI, Dr. Chow has received the ASA Chapter Service Recognition Award, the DIA Outstanding Service Award, and the ICSA Extraordinary Achievement Award.

Chin-Fu Hsiao is an investigator in the Institute of Population Health Sciences at the National Health Research Institutes in Taiwan. Dr. Hsiao is also an adjunct associate professor at National Chiao Tung University. His research interests encompass Bayesian analysis, clinical trials, and genetic study.