4BIO Capital Research
Investment Thesis
4BIO Capital is a London-headquartered specialist biotech venture firm dedicated exclusively to advanced therapies addressing high unmet medical and social needs. Founded in 2014 as 4BIO Partners LLP, the firm is authorized and regulated by the Financial Conduct Authority (Reference Number 842764) and is a member of the British Private Equity and Venture Capital Association (BVCA). The firm's core thesis is that the future of medicine lies in next-generation therapeutic platforms—cell and gene therapy, RNA-based therapy, targeted therapies (including antibody-drug conjugates), the microbiome, and radiopharmaceuticals—and that exceptional returns will accrue to investors who back the scientists and clinical teams capable of translating these platforms into approved medicines.
4BIO describes itself as a 'therapeutic navigator,' providing not just capital but deep scientific expertise and strategic guidance to help portfolio companies move from discovery-stage innovation through IND-enabling studies to clinical development. The firm is a signatory of the UN Principles for Responsible Investment and actively implements ESG criteria in its practices, with a specific emphasis on UN Sustainable Development Goal #3 (Good Health and Well-Being).
Sector Focus
4BIO invests exclusively in biotech and life sciences, with a particular concentration on advanced and emerging modalities:
- Cell therapy: Including engineered T-cell and gamma delta T-cell approaches
- Gene therapy: AAV-based gene delivery for inherited and degenerative diseases (retinal, neurological, rare diseases)
- RNA-based therapy: mRNA and RNA-interference approaches
- Antibody-drug conjugates (ADCs): Next-generation targeted oncology payloads
- Radiopharmaceuticals: FAP-targeting and other precision radiotherapy approaches
- Microbiome: Therapeutics leveraging the gut and other microbiomes
- Precision viral immunotherapy: Oncolytic and viral-based cancer therapies
The firm explicitly avoids chemistry-based small molecule drugs in favor of biology-based, genetically defined therapeutics. Key disease areas include rare genetic diseases, degenerative disorders (cardiovascular, neurodegenerative), oncology (particularly glioblastoma and solid tumors), and ophthalmology.
Stage Focus
4BIO focuses on early-stage investing, primarily at the pre-seed, seed, and Series A stages. The firm is particularly active in company creation and incubation—spinning out ventures directly from academic institutions (e.g., Trogenix was co-founded by 4BIO with the University of Edinburgh in 2023) and providing first-institutional-capital to scientific founders. The firm also participates in follow-on rounds at Series B and beyond to maintain positions in breakout portfolio companies (e.g., Ray Therapeutics' $125M Series B in 2026).
Check Size & AUM
The firm manages multiple funds: 4BIO Ventures II and 4BIO Ventures III. Ventures III is targeting $200–300 million with institutional LPs including Children's Minnesota, UPMC, Development Bank of Japan, Kyowa Kirin, and Exor. Total AUM is estimated at over $300 million across funds. Typical individual investment amounts are $5–10 million per company, though 4BIO frequently leads larger syndicated rounds; recent lead investments include a $28.4M Series A for March Biosciences (2024), a $75.5M Series A for Actithera (co-led, 2025), and an £61M ($83M) Series A for Cytospire Therapeutics (2026).
Lead Tendency
4BIO Capital consistently leads investment rounds. Examples include:
- Led SparingVision's €44.5M Series A (2020)
- Led Ray Therapeutics' seed round (2021)
- Led March Biosciences' $28.4M Series A (2024)
- Co-led Actithera's $75.5M Series A (2025)
- Led Cytospire Therapeutics' £61M Series A (2026)
The firm takes board seats at portfolio companies as part of its active, hands-on investment approach.
Recent Activity
4BIO Capital is actively deploying capital from Ventures III (closed/deploying as of 2024). Notable recent investments:
- May 2026: Led oversubscribed £61M ($83M) Series A for Cytospire Therapeutics (pan-gamma delta T cell engager antibodies for solid tumors)
- April 2026: Participated in Ray Therapeutics' upsized $125M Series B (optogenetic gene therapy for retinal degeneration; 4BIO is founding investor from 2021 seed)
- October 2025: Portfolio company Trogenix (4BIO-founded) secured £70M ($95M) Series A led by IQ Capital
- July 2025: Co-led Actithera's oversubscribed $75.5M Series A (radiopharmaceuticals)
- March 2025: Portfolio company Araris Biotech agreed to be acquired by Taiho Pharmaceutical for up to $1.14B—a landmark exit
- October 2024: Led March Biosciences' $28.4M Series A (precision immune therapies for cancer)
Portfolio Highlights
Notable Exits:
- Araris Biotech (acquired by Taiho Pharmaceutical, March 2025, up to $1.14B) — ADC drug discovery
- Orchard Therapeutics (acquired by Kyowa Kirin, ~$477.6M) — gene therapy for rare diseases
- ADC Therapeutics (NYSE IPO, May 2020, market cap ~$1.31B)
- Autolus (NASDAQ IPO, $22.5M market cap at listing) — T-cell therapy
- UniQure (IPO) — gene therapy
Active Portfolio Highlights:
- Ray Therapeutics — Leading optogenetic gene therapy for retinitis pigmentosa and macular diseases; $125M Series B (April 2026)
- Cytospire Therapeutics — Pan-gamma delta T cell engager antibodies for EGFR-positive solid tumors; £61M Series A (May 2026)
- Actithera — FAP-targeting radiopharmaceuticals; $75.5M Series A (July 2025)
- Trogenix — Precision viral immunotherapy for glioblastoma; £70M Series A (October 2025)
- March Biosciences — Precision immune therapies for aggressive cancers; $28.4M Series A (October 2024)
- Ascend Advanced Therapies — End-to-end gene therapy development; acquired Florida GMP manufacturing (April 2024)
- SparingVision — AAV gene therapy for retinitis pigmentosa; €44.5M Series A (October 2020)
- Entact Bio — Early portfolio company
- Code Biotherapeutics — RNA/gene therapy
- LUCA Sciences — Tokyo-based advanced therapeutics
Team
4BIO Capital is led by two Co-founders and Managing Partners:
- Andrew Kozlov (Managing Partner): Co-founder; leads investment strategy and portfolio oversight
- Dima Kuzmin (Managing Partner): Co-founder; Chairman of Trogenix, board member at Ray Therapeutics; PhD scientist with deep expertise in advanced modalities
- Therese Liechtenstein (Partner): PhD in Immuno-Oncology from UCL; previously Senior Investment Director at M Ventures (Merck KGaA); board roles at Actithera and Araris Biotech; based in Munich
- Kieran Mudryy (Partner): LLB background; handles legal and investment structuring aspects
- Vasily Fedorin (COO): PhD; operations and fund management
- Natalie Johnston (Investment Principal): PhD scientist; leads deal sourcing and portfolio support
- Owen Smith (Investment Analyst/Partner): CPFA; board observer at SparingVision; noted as 'Partner' in Cytospire announcement
- Brian McVeigh (Venture Partner, USA): MBA; covers US deals from North America
- Philippe Fauchet OBE (Venture Partner, Japan): Covers Japan and Asia-Pacific
- Tetsu Maruyama (Venture Partner, Japan): PhD; Japan operations
- Jack Shea-Firth (Venture Partner): PhD
- Tay Salimullah (Investment Analyst): 20+ years in rare disease and MedTech; former Novartis Gene Therapies Executive Committee member
- Alexander McKenna (Investment Associate): PhD
Geographic Focus
4BIO invests across Europe (UK and continental Europe, particularly Germany, Switzerland, France, Netherlands), the United States, and Japan. The London headquarters serves as the primary deal hub. The firm has maintained a Japan investment strategy since 2018 and in November 2024 became the first UK-based venture fund certified by Japan's Agency for Medical Research and Development (AMED), enabling 4BIO portfolio companies to access AMED non-dilutive grants.
Decision Process
4BIO operates as a partnership with two Managing Partners (Kozlov and Kuzmin) plus two additional Partners (Liechtenstein and Mudryy). Investment decisions are made collectively, with the GP team typically represented on portfolio company boards. Given the firm's specialized biotech focus, the team conducts rigorous scientific due diligence, often led by PhD-trained investment professionals.
Founder Preferences
4BIO backs founders and scientific teams with strong academic credentials and deep domain expertise in advanced therapeutic modalities. The firm frequently co-founds companies with academic scientists (e.g., Trogenix with University of Edinburgh). They prefer teams that have a clear technical differentiation and are addressing diseases with high unmet medical need where existing treatments are inadequate or non-existent.