A generative AI medical device is medical software built on large language models. It can review different types of health information, such as clinical notes, images, and lab results, and produce new content, such as a summary or an answer to a clinical question. A GenAI medical device can handle open-ended questions and combine information from multiple sources, unlike most AI-based medical software, which performs one narrow task, such as flagging a suspicious skin lesion, and gives the same answer for the same input. On October 14, 2026, Japan’s Pharmaceuticals and Medical Devices Agency (PMDA) released a provisional English translation of its draft review points for GenAI medical devices. The draft was first issued in September for public comment. The PMDA notes that it has not yet reviewed a GenAI device for approval.
The draft covers devices built on large language or vision-language models. The PMDA urges developers to define a clear, limited clinical claim. Broad diagnostic tools may need to start narrow and expand over time. Testing should reflect real clinical settings, check for serious errors, and confirm that answers remain valid when questions are reworded or reordered.
Developers also need a plan for changes outside their control, such as foundation model updates through a cloud service or changes to the data a system draws on. That plan should cover which versions can be locked down, which changes can be detected, and how to respond if performance drops. The PMDA expects post-market monitoring of performance, adverse events, and AI hallucinations to be planned during development.
On the user side, the draft recommends citing verifiable sources and using guardrails to block inappropriate requests. Some imperfections in outputs will not rule out approval if the risks can be managed. Separately, the PMDA lists most fee-based software consultations as available only from January 2027 onward.
Written by: Ames Gross – President and Founder, Pacific Bridge Medical (PBM)
Mr. Gross founded PBM in 1988 and has helped hundreds of medical companies with regulatory and business development issues in Asia. He is recognized nationally and internationally as a leader in the Asian medical markets. Mr. Gross has a BA degree, Phi Beta Kappa, from the University of Pennsylvania and an MBA from Columbia University.