# Saisei Ventures

Saisei Ventures is a Venture Capital based in Cambridge, United States.

## Overview

- **Organization type:** Venture Capital
- **Headquarters:** Cambridge, United States
- **Region:** North America
- **Address:** One Broadway, 14th Floor, Kendall Square, Cambridge, MA 02142, United States
- **Founded:** 2020
- **Assets under management:** Undisclosed
- **Website:** www.saiseiventures.com
- **LinkedIn:** https://www.linkedin.com/company/saisei-ventures

## Regulatory record

- **Reports private funds:** No

## About

Saisei Ventures is a leading venture capital firm focused on growing and harnessing the Japanese biotech ecosystem. It creates ventures from bold ideas and empowers entrepreneurs by filling technical, operational, or financial gaps. Its approach combines Western expertise and Japanese innovation to build globally competitive companies with impact on patient lives. The firm takes a hands-on, science-first approach and actively builds companies from revolutionary science.

## Sectors

- Digital Health
- AI/ML

## Offices

- Tokyo, Japan

## People

- Jonathan Yeh — Managing Partner
- Hikaru Saito — Partner
- Sven Kili — Partner

## Questions

### Who runs investment decisions at Saisei Ventures?

Managing Partner Jonathan Yeh leads Saisei's investment activities. The firm discloses two additional Partners—Hikaru Saito and Sven Kili (appointed January 2025)—alongside Venture Partners James Feliciano and Toshihiko Komori (per the firm website, 2025). The partnership operates from Cambridge and Tokyo, making investment decisions as a cross-border team rather than delegating authority to a single remote office.

### How does Saisei Ventures source proprietary deal flow?

Saisei sources proprietary opportunities by operating directly within Japan's academic and research ecosystem rather than competing for crowded US and European syndicated rounds. The firm's Tokyo office and local network provide access to Nobel-caliber science—Japan has 22 science Nobel laureates including Dr. Shinya Yamanaka for induced pluripotent stem cells—that remains under-capitalized by Western VCs. Saisei also builds new ventures around promising academic discoveries, creating deal flow that did not previously exist as a fundable company.

### How is Saisei Ventures' approach to Japan different from other biotech VCs?

Most Western biotech investors treat Japan as an occasional deal source; Saisei has built its entire investment thesis around it. The firm embeds personnel in Tokyo, sources directly from Japanese research institutions, and actively recruits operational talent to fill the leadership gaps that often prevent Japanese science from reaching global clinical trials. Saisei launched an Executive Fellows Program in April 2025 to build the management pipeline that makes this model sustainable.

### Which therapeutic modalities does Saisei Ventures focus on?

Saisei concentrates on advanced therapeutic platforms, specifically cell immunotherapies, pluripotent cell replacement therapies, in vivo and ex vivo gene therapy approaches, and epigenetic editing. The firm is indication-agnostic as long as the target is a life-threatening or debilitating disease with a reasonable path to clinical and commercial manufacturing scale.

### Does Saisei Ventures disclose its assets under management?

No. Saisei Ventures does not publicly disclose assets under management, fund sizes, or total deployment figures. The firm's website provides no AUM or dry-powder data, and no external financial publication has reported verified fund-raise numbers as of mid-2025.

## Related profiles

- [Saiph Capital](https://altss.com/profile/saiph-capital)
- [Saishunkan Pharmaceutical](https://altss.com/profile/saishunkan-pharmaceutical)

---

Last updated: 2026-08-11T15:08:04.536Z

Canonical page: https://altss.com/profile/saisei-ventures

Maintained by Altss — https://altss.com — methodology: https://altss.com/methodology