# Bios Partners

> Bios Partners is a Fort Worth venture-capital firm that backs early-stage and growth biotechnology, biopharmaceutical and medical-device companies, with an explicit focus on scientifically strong opportunities outside the coastal venture hubs. Its model combines fund capital with scientific diligence, public-market analysis and hands-on company cultivation across clinical development, financing and commercialization.

- **Founded:** 2014
- **Headquarters:** Fort Worth, United States
- **Founders:** Aaron G.L. Fletcher, PhD (Managing Partner and Co-Founder), Leslie W. Kreis, Jr. (Managing Partner and Co-Founder), Stella M. Robertson, PhD (Co-Founder and Partner)
- **Team size:** 16 employees listed on LinkedIn; the company page describes a 2-10 employee size band.
- **Products:** Life-sciences venture investing, Scientific and commercial diligence, Portfolio company cultivation, Clinical Opportunity Fund
- **Notable:** Closed Bios Fund I and had made seven new investments from the vehicle by March 2017., Led 410 Medical's $3.3 million initial Series A investment in 2017., Led Lung Therapeutics' $14.3 million Series B in 2017.

## Products & services

- **Life-sciences venture investing** — Equity investment in early seed through later-stage growth biotechnology, biopharmaceutical and medical-device companies.
- **Scientific and commercial diligence** — Technical review informed by biochemistry, drug development, clinical trials, biostatistics and public healthcare-market research.
- **Portfolio company cultivation** — Board participation and support with company strategy, financing, clinical development, investor relations and commercialization.
- **Clinical Opportunity Fund** — A later vehicle visible in public filings that invests in clinical-stage public and private life-sciences opportunities.

## Achievements

- Closed Bios Fund I and had made seven new investments from the vehicle by March 2017.
- Led 410 Medical's $3.3 million initial Series A investment in 2017.
- Led Lung Therapeutics' $14.3 million Series B in 2017.
- Led Trefoil Therapeutics' oversubscribed $28 million Series A in 2019.
- Led ONL Therapeutics' $46.8 million Series B in 2020 and $15 million Series C in 2023.
- Portfolio company Encore Vision was acquired by Novartis in January 2017.
- Portfolio companies including Cognition Therapeutics, IN8bio, Actuate Therapeutics and Opus Genetics reached public markets.
- Participated in ONL Therapeutics' oversubscribed $65 million Series D in 2024.
- Participated in Rein Therapeutics' $57.5 million public offering in 2026.

## Latest updates

- **2026-05** — Bios Partners joined existing and new healthcare investors in Rein Therapeutics' $57.5 million underwritten public offering.
- **2025-09** — An SEC ownership filing showed Bios-affiliated entities holding a significant position in Cognition Therapeutics.
- **2024-09** — Bios Partners participated in ONL Therapeutics' $65 million Series D to advance a global Phase 2 study in geographic atrophy.
- **2024-08** — Portfolio company Actuate Therapeutics completed its Nasdaq initial public offering under the ticker ACTU.
- **2023-08** — Bios Partners led ONL Therapeutics' $15 million Series C financing.

## Links

- Website: https://biospartners.com
- LinkedIn: https://www.linkedin.com/company/bios-partners

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Profile page: https://yespress.io/bios-partners
Published by YesPress — https://yespress.io
Last updated: 2026-08-16