Bridging Data between Two Ethnic Populations. A New Application of Matched Case-Control Methodology


Utilizing foreign clinical data from a large-scale trial to draw conclusions about the safety and efficacy of a drug in a new region will eliminate the need to repeat a large-scale clinical trial in the new region. This approach is not only cost-effective; it expedites the approval of valuable new drugs, so subjects in the new region can benefit sooner from new therapies that are currently helping millions of people worldwide. The International Conference on Harmonization (ICH) E-5 guideline (ICH Harmonized Tripartite Guideline E-5: Ethnic factors in the acceptability of foreign clinical data,) indicates that a bridging study can be performed in a new region to provide efficacy, safety, and dosage information and allow subsequent extrapolation of foreign clinical data to the population in that new region. However, this definition does not identify appropriate statistical methods for “bridging” the two populations. The statistical method proposed in this article selects subjects from the global population who have characteristics similar to those of subjects in the new region. These methods have been used in other applications, but not to bridge data. The paper describes a new application of this methodology and evaluates other methodologies proposed for bridging. An example of how the proposed methodology can be used to bridge global clinical trial data to a new population is also provided.

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Correspondence to Somnath Sarkar PhD.

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Sarkar, S., Watts, S., Ohashi, Y. et al. Bridging Data between Two Ethnic Populations. A New Application of Matched Case-Control Methodology. Ther Innov Regul Sci 36, 349–356 (2002).

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Key Words

  • Baseline demographics
  • Bridging study
  • Clinical trial
  • Propensity score
  • Statistical methodology