Shinsuke Okui

Cubec Inc. (Cubec) is a startup based inside the National Cerebral and Cardiovascular Center in Suita, Osaka. It develops its own generative AI specialized in healthcare, including a clinical knowledge AI app that provides doctors, in one place, with highly reliable answers to the questions that come up in their practice. We asked CEO Shinsuke Okui, who says, “I want to create a world where everyone can naturally reach the best medical care for them,” about the path to founding the company and what lies ahead.

Reducing the rate of false information by specializing in doctors’ clinical questions

Community medicine in Japan faces the threat of collapse, with demand rising as society ages and doctors in short supply as the working population shrinks. Meanwhile, the family doctors who are the first to see patients in a community are often required to make important diagnoses about diseases outside their own specialty, and in that situation, more than one in four doctors look things up on Google or in medical books at least once a day (our own survey).

Our Clinical Knowledge AI “Cubec” is an app that answers doctors’ questions based on reliable evidence. When a doctor enters a question, the AI grasps the intent, searches databases such as research papers for information, and answers along with the sources. We believe our big strengths are that every answer comes with solid evidence, and that doctors can ask questions in the natural language they use every day.

The competitors we benchmark against are general-purpose generative AI such as ChatGPT and Google Gemini. The problem with these services is the reliability of the information. By focusing on doctors’ clinical questions, our AI greatly reduces the rate of hallucinations (generation of false information). Doctors who are test users have told us that “it is more reliable than other generative AI and gets straight to the point.”

In fall 2025, we plan to upgrade it so it can handle information such as clinical practice guidelines and package inserts, in addition to research papers. We are also building training data on so-called “experiential knowledge” to widen the range of questions it can answer, aiming to launch it as our own AI model in 2026.

Realizations and encounters that led me to start a company

After graduating from university, I began my career in sales and marketing at a pharmaceutical company. Talking with the doctors who handle community medicine, I realized something: however much they want to save patients, there is a limit to what they can do with limited time and in their circumstances.

I focused on the chronic condition commonly called “heart failure.” As society ages, the number of patients is growing, but because the disease takes many forms and there are many things to keep track of, it is a heavy burden to treat, especially for doctors who are not cardiology specialists, and they were treating it through trial and error.

At the time, I myself had a family member with an intractable disease, so I keenly felt how hard treatment choices and self-care can be. I began to think, “Can we solve the problem that whether people can reach the best care depends on differences in their environment, such as the patient’s own health literacy and where they live?”

Then, through meeting a leader from my pharmaceutical company days who taught me how important it is to work with a mission, the words “The best medical care, in everyone’s hands” came to me.

Soon after, I met Niida (now co-founder, Director and CAIO), an AI specialist in healthcare, and Dr. Saku of the National Cerebral and Cardiovascular Center (now Director and Chief Medical Officer), and we founded the company in 2023. In August 2024, the following year, we were certified as a venture originating from the Center, and in June 2025 we moved our head office into the Center.

The words that came to me back then, when I saw my own experience and the realities of medical practice as problems to solve, “The best medical care, in everyone’s hands,” remain our company’s mission today.

Developing medical devices with design thinking

Besides Cubec’s Clinical Knowledge AI, we are running two projects. One is “Heart Failure Care Support AI,” in which AI suggests diagnoses and treatments for heart failure patients. The other is “Pulmonary Hypertension Care Support AI,” which connects pulmonary hypertension patients, their family doctors, and specialists to make care run smoothly.

Both are supported by AMED (Japan Agency for Medical Research and Development), and we are conducting joint research with several universities and hospitals, led by the National Cerebral and Cardiovascular Center. For both, our goals are to obtain regulatory approval as medical devices in 2029 and to begin selling them as medical devices in 2030.

In developing these medical devices, “design thinking,” a way of thinking I studied at an art university’s graduate school before starting the company, has been useful. As I came to understand design thinking, I learned “how much I was caught up in my own assumptions,” felt keenly how hard it is to free myself from them, and learned how important it is to “observe” things with my own eyes and ears. That is why, with the cooperation of doctors, our development process moves forward while we actually “observe” medical practice.

Going forward, the medical crisis caused by staff shortages is expected to spread not only in Japan but to other Asian countries as well. With that in mind, we are also looking at developing services for overseas markets and medical support services for the general public. Aiming to “realize a world where everyone can reach the best medical care for them,” we want to keep developing as one team.

How We Used OIH

When we were raising funds, OIH introduced us to many investors. We were also selected for the 17th cohort of the accelerator program “OSAP,” where OIH introduced us to people at several related operating companies as we tested our business hypotheses, giving us many chances for discussion. Then, after winning the “HeCNOS AWARD,” we went on to exhibit at Expo 2025 Osaka, Kansai, Japan, which also helped raise our profile. I truly feel that our connection with OIH is one of the driving forces moving our business forward.