Outer Bio Emerges from Stealth with Yuna, a Platform That Keeps Ex Vivo Human Skin Alive and Measurable for Four Weeks

Living, full-thickness human skin, that stays viable outside the body for a month or more – far longer than conventional skin explants – forms the data foundation for AI-driven discovery of new skin bioactives

The validation is public: a bioRxiv preprint documents Yuna reproducing three distinct skin biologies across the four-week window

CAMBRIDGE, Mass., August 24, 2026--Outer Bio, a discovery company for skin bioactives, today emerged from stealth and released Yuna, an ex vivo human-skin platform that keeps full-thickness skin alive and measurable for over four weeks — substantially longer than standard ex vivo skin — with its native architecture and immune function intact. Yuna is the data-generation and validation engine beneath Outer Bio's approach: a way to generate reproducible, high-fidelity, clinically relevant human-skin data at a duration and level of detail the field has lacked, and the foundation for the company's machine-learning-driven discovery of new bioactives.

The skincare industry generates more than $100 billion a year, yet in three decades it has added essentially one FDA-approved topical mechanism that meaningfully improves visible skin aging: retinoids. The constraint has been technical, not commercial. Taken out of the body, human skin survives in the lab for less than a week. But the processes that determine whether and how a compound works — collagen remodeling, chronic inflammation, cellular senescence — unfold over weeks. The field has been forced to judge long-term biology inside a short-term window.

Yuna closes that gap. It holds full-thickness human skin including epidermis, dermis, multiple cell types, and resident immune function alive for four or more weeks. The tissue is sourced from donors across ages, sexes, and Fitzpatrick skin types I through VI and read out by longitudinal multi-omic measurements spanning transcriptomics, histology, and secreted proteins, building an ever-expanding dataset that improves the platform's performance over time. Each compound-sample pair generates more than 30,000 data points; to date, the platform has produced over 10 terabytes of proprietary data across more than 300 donors and 10,000 treatments. Because the platform relies on living human tissue rather than a reconstructed model or a cell line, signals observed in Yuna are grounded in native human skin biology and can support clinical translation.

On that foundation, Outer Bio is building an integrated discovery engine that pairs machine learning with every experiment: models trained on the platform's data prioritize which compounds to test, and each result sharpens the next round of predictions. The company's virtual screening library already spans 5.9 million compounds across 11 databases, with a roadmap toward billions of synthesizable structures.