[The Background of rt-PA Implementation and Its Impact on Nationwide Adoption in Japan]

Around the year 2000, Japan became a global leader in clinical research on intravenous recombinant tissue plasminogen activator (rt-PA). However, due to patent-related issues surrounding the drug, domestic development came to a standstill, plunging the country into a prolonged "dark age" for reperfusion therapy. In contrast, alteplase was approved in the United States in 1996, and rt-PA treatment soon became widely adopted worldwide. Japan, however, could not introduce rt-PA until 2005. Following its approval, stroke care in Japan underwent a dramatic transformation. The concept that "time is brain" became deeply ingrained in the field, and minimizing the time from symptom onset to intravenous rt-PA administration emerged as the most critical challenge for the entire healthcare system. This shift represented far more than the addition of a new therapeutic option; it catalyzed sweeping reforms across multiple domains, including public awareness, establishment of prehospital emergency medical services (EMS), improvements in hospital triage and acceptance processes, acute management in stroke units and stroke care units (SU/SCUs), development of stroke centers, revisions to emergency reimbursement under the national insurance system, and education and training of medical personnel. The advent of rt-PA marked a watershed moment in acute stroke care, fundamentally reshaping treatment paradigms.