The international conference on harmonization (ICH5) bridging study’s idea was adopted in 1998 as a practical concept in enhancing globalization of clinical trials. The rationale necessitating the bridging studies, includes but are not limited to the differences in regions, new age groups and change in manufacturing/storage methodology (Day, S. 2008). The purpose of bridging studies became apparent as medicinal products need extensive evaluation in identifying potential impact of ethnic factors on a product’s efficacy and safety (Day, 2008).

The importance of bridging studies in science and public health cannot be reduced to the context of cultural differences. On the other hand, the scientific validity on the effects of ethnic differences is not limited to safety, efficacy, dosage and dose regimen of a medicinal product, but other inherent factors have inevitable and unavoidable risks on medicinal products efficacy and safety issues (Day, 2008). For instance, intrinsic and extrinsic factors categorized in bridging studies as ethnic sensitivity and insensitivity respectively are also considerable and important factors in bridging studies (Day, 2008).

Ethnic sensitivity factors include pharmacokinetics, pharmacodynamics, genetic polymorphism, metabolism, bioavailability, therapeutic range, drug interaction, inter-subject variability, systematic mode of action, and inappropriate use of drugs (Day, 2008). These factors put together, is relevant in identifying the differences between completed studies and local factors. In addition, bridging studies is essential in the proof on concept studies. It also provides better assessment methodology in evaluating the safety and efficacy of a medicinal product when there are divergent cultural and medical practices.

Furthermore, when drug class is unfamiliar or clinical experience is deemed insufficient, bridging studies are unquestionably essential (Day, 2008). In cases where new medicinal products has no known analogue or history, scientists are very cautious with their use. Thus, conducting bridging studies with unfamiliar medicinal products may validate the safety and efficacy of the product in question. In addition, clinical experience is sometimes deemed insufficient when scientific data is in lack of conclusive evidence to support reported claims, or the sample size or population variability of subjects who participated in the clinical trial was not large enough to generate convincing data to suggest a conclusive scientific opinion or affirm the study claims.

Bridging studies cover a broad range of applicability of any medicinal product such that product effects on human genomic biodiversity or genetic polymorphism assessment is possible (Day, 2008). The effects of inter or intra-specie polymorphisms on drug efficacy and safety is not de minimus (Kopin, McBride, Gordon, Quinn, & Beinborn, 1997). Hence, bridging studies add substantial benefits to public health awareness programs and enhance scientific breakthroughs or positive outcomes, which could outweigh the risks posed by the product.

Without crossing cultural or ethnic human variation, the inherent effect of intra-polymorphism on drugs efficacy and safety, may indicate a positive or negative outcome (Kopin, et al. 1997). Therefore, the effects of intra-polymorphism alone trigger valid concerns or the need for bridging studies. In addition, it bridges cultural differences within the population without compromise or disregard of the extrinsic cultural and religious factors. Several factors play an essential role in bridging studies. However, there are many challenges facing medical professional and the ICH in providing competent globalization platform for clinical trials

References

Abraham, J., & Reed, T. (2001). Trading risks for markets: The international harmonisation of pharmaceuticals regulation. Health, Risk & Society, 3(1), 113–128. Retrieved  from http://ezp.waldenulibrary.org/login?url=http://search.ebscohost.com/login.aspx?direct=tru e&db=a9h&AN=4139555&site=ehost-live&scope=site

Day, S. (2008).  Multi-regional studies and bridging studies. Retrieved from http://ocw.jhsph .edu/courses/BiostatMedicalProductRegulation/biomed_lec10_day.pdf.

Dombey,S., Hamrell,M., & Woodin, K. (2012).  International harmonization of clinical research.  Retrieved from http://sylvan.live.ecollege.com/ec/crs/default.learn? CourseID=6 493792&Survey=1&47=10828390&ClientNodeID=984640& coursenav=1&bhcp=1.

European Medicines Agency. (1998). ICH topic E-5 (R1) ethnic factors in the acceptability of Foreign Clinical Data Retrieved from http://www.ema.europa.eu/docs/en_GB/document_ library/Scientific_guideline/2009/09/WC500002842.pdf

Jhee, S. S., & Franckiewicz, E. J. (2003). Bridging strategies may help put Western drugs on the Japanese market. Applied Clinical Trials, 12(9), 32–35. Retrieved from http://ezp.Wald enuli brary.org/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=a 9h&AN=10759796&site=ehost-live&scope=site 

Kopin, A., McBride, E., Gordon, M., Quinn, S., & Beinborn, M. (1997). Inter- and intra-species polymorphisms in the cholecystokinin-B/gastrin receptor alter drug efficacy. Proc. Natl. Acad. Sci. 94,11043–11048. Retrieved from http://www.ncbi.nlm.nih.gov/ pubmed/9380756

Wiktorowicz, M. E. (2003). Emergent patterns in the regulation of pharmaceuticals: Institutions and interests in the United States, Canada, Britain, and France. Journal of  Health Politics, Policy and Law, 28(4), 615–658. Retrieved from http://ezp.waldenulibrary. org/login?url= http://search.ebscohost.com/login.aspx?direct=true&db=a9h&AN=107 69953 &site=ehost-live&scope=site .