# Ataraxis AI

> Ataraxis AI is a New York-based precision-oncology company building AI-native cancer diagnostics. Founded in 2022 by physician-scientist Jan Witowski and AI researcher Krzysztof Geras, it developed Kestrel, a digital-pathology foundation model trained on hundreds of millions of tissue images. Its flagship platform, Ataraxis Breast, reads standard pathology slides to predict recurrence risk and estimate whether an individual patient will benefit from chemotherapy - reported to be roughly 30% more accurate than the current standard of care - returning results within about an hour and without additional tissue procedures.

- **Founded:** 2022
- **Headquarters:** New York, New York, United States
- **Founders:** Jan Witowski (CEO & Co-Founder), Krzysztof Geras (Chief Scientific Officer & Co-Founder)
- **Team size:** ~32 employees
- **Products:** Kestrel, Ataraxis Breast, Ataraxis Breast CTX
- **Notable:** Built Kestrel, a digital-pathology foundation model trained on hundreds of millions of cancer-tissue images., Launched what it calls the world's first AI-native prognostic/predictive cancer diagnostic., Reported clinical validation showing ~30% higher accuracy than the standard of care for breast cancer.

## Products & services

- **Kestrel** — Ataraxis's foundation model for digital pathology, pretrained on hundreds of millions of pathology images using vision transformers and self-supervised learning, with proprietary methods to optimize and scale the models.
- **Ataraxis Breast** — AI-native prognostic and predictive platform for breast cancer that reads standard pathology slides to assess recurrence risk, chemotherapy benefit, and neoadjuvant response - reported ~30% more accurate than standard of care, with results in about an hour.
- **Ataraxis Breast CTX** — First predictive AI test estimating individualized chemotherapy benefit in breast cancer, predicting outcomes with and without adjuvant chemotherapy; powered by Ataraxis Tau, a causal-inference layer that corrects for treatment-selection bias in real-world data.

## Achievements

- Built Kestrel, a digital-pathology foundation model trained on hundreds of millions of cancer-tissue images.
- Launched what it calls the world's first AI-native prognostic/predictive cancer diagnostic.
- Reported clinical validation showing ~30% higher accuracy than the standard of care for breast cancer.
- Raised a $20.4M Series A led by AIX Ventures with Founders Fund and Thiel Bio participating.
- Adoption by NCI-designated cancer centers and community clinics following the Breast CTX launch.

## Latest updates

- **2026-03** — Launched Ataraxis Breast CTX, the first predictive AI test estimating individualized chemotherapy benefit in breast cancer, powered by the Ataraxis Tau causal-inference layer.
- **2025-03** — Announced a $20.4M Series A led by AIX Ventures to accelerate clinical deployment of AI precision medicine.
- **2024-10** — Emerged from stealth with a $4M seed round and the launch of Ataraxis Breast.

## Links

- Website: https://ataraxis.ai
- LinkedIn: https://www.linkedin.com/company/ataraxis-ai/
- Twitter/X: https://twitter.com/Ataraxis_AI

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Profile page: https://yespress.io/ataraxis-ai
Published by YesPress — https://yespress.io
Last updated: 2026-07-22