bridging trials

Japan is the second largest pharmaceutical market in the world, and it’s growing faster than US and EU markets – but  complex regulatory issues, and the need to assess the influence of ethnicity on the safety and efficacy of medicines, make getting new drugs into the Japanese market a lengthy and difficult process. At HMR, we’ve completed over 30 Phase 1 Japanese ‘bridging’ trials which have helped to detect ethnic variations among global populations in the safety and pharmacokinetics of drugs, thereby allowing effective planning of the later phases of global drug development. Bridging trials can help to reduce the cost and increase the efficiency of future development programmes, and fast-track drugs into Japan.

At HMR, we have over 15 years’ experience of bridging trials comparing europid subjects with their Japanese counterparts. We’ve even done 3 trials to compare europid, Japanese, Korean and Chinese subjects. We ensure that trials done at HMR are carefully designed to meet the strict regulations of Japan’s Pharmaceutical and Medical Devices Agency (PMDA). At HMR, we’ve completed –

  • bioequivalence trials of new products not yet marketed in Japan
  • trials that can’t be done in Japan, such as a trial of an opioid
  • ‘add-on’ cohorts of Japanese subjects in large, complex trials in europids
  • first-in-human trials
  • trials of biological products, including monoclonal antibodies and siRNA
  • trials in Japanese poor and extensive metabolisers
  • PET trials in Japanese subjects

Our dedicated team of 20 bilingual Japanese nurses and support staff have great experience of bridging trials. They recruit suitable subjects, translate trial documents, and help to do the trials. With about 65,000 Japanese people living in the UK, and with the largest population living in London, we’re perfectly situated and resourced to complete your bridging trials. All of our subjects meet the PMDA’s established criteria: they hold a Japanese passport; their parents and all 4 grandparents are Japanese; and they’ve lived outside of Japan for less than 5 years.



  1. ICH Topic E 5 (R1). Ethnic factors in the acceptability of foreign clinical data. EMA, Sept 1998
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  4. Lister N, Warrington S, Boyce M et al. The pharmacokinetics, safety and tolerability of ascending doses of sublingual fentanyl (KW-2246) in Japanese subjects, with and without naltrexone. J Clin Pharmacol 2011; 51: 1195–1204
  5. Small D et al. Pharmacokinetics and pharmacodynamics of prasugrel in healthy Japanese, Chinese, Korean and Caucasian subjects. Eur J Clin Pharmacol 2010; 66: 127–135
  6. Toublanc N, Okagaki T, Boyce M, Chan R, Mugitani A, Watanabe S, Yamamoto K, Yoshida K, Andreas JO. Pharmacokinetics of the antiepileptic drug levetiracetam in healthy Japanese and Caucasian volunteers following intravenous administration. Eur J Drug Metab Pharmacokinet 2015; 40: 461–469.