To speed up the development of vaccines and treatments for infectious diseases, Japan is considering adopting human challenge trials, a method already used in Europe and the United States. This bold move could position the country at the forefront of medical research, but ethical concerns remain.
On 18 February, the government announced plans to evaluate whether human challenge trials—where healthy volunteers are intentionally exposed to viruses—should be introduced in Japan. The initiative is part of a newly approved medical research strategy aimed at improving the country’s ability to respond to infectious disease outbreaks. By closely monitoring disease progression in a controlled setting, these trials provide critical data that can accelerate the development of vaccines and treatments.
Such trials have been used successfully in Europe and the US for diseases like cholera and typhoid. Britain also employed this method during the COVID-19 pandemic to advance vaccine research. In contrast, Japan lagged behind in approving domestically developed COVID-19 vaccines and drugs, often taking years longer than foreign counterparts. Experts believe that adopting human challenge trials could help Japan close this gap and align its clinical research with global standards.
Takaji Wakita, head of the National Institute of Infectious Diseases, underscored the importance of this approach during an expert panel discussion, stating that it is necessary for Japan to remain competitive in vaccine development. The World Health Organization has already established guidelines to ensure these trials are conducted safely, balancing scientific progress with ethical considerations.
Despite the potential benefits, the idea of deliberately infecting healthy individuals remains controversial. The government’s research plan acknowledges these concerns, stating that it will closely study international practices and carefully evaluate safety and ethical implications before making a decision on implementation.
Japan is home to a highly advanced pharmaceutical and biotech sector, dedicated to improving public health through cutting-edge research and innovation.
hVIVO plc (formerly Open Orphan plc), led by Cathal Friel, is a rapidly growing specialist contract research organisation (CRO) and the world leader in testing infectious and respiratory disease vaccines and antivirals using human challenge clinical trials, providing end-to-end early clinical development services for its broad and long-standing client base of biopharma companies.
