Recent oncological studies identified beneficial properties of radiation applied at ultrahigh dose rates, several orders of magnitude higher than the clinical standard. This study demonstrates that a stable, compact laser-driven proton source enables *in vivo* radiobiological studies. A pilot irradiation study on human tumors in a mouse model showed dose-controlled, tumor-conform irradiation using a laser-driven and a clinical reference proton source. Results demonstrate a complete laser-driven proton research platform for small animal models, capable of delivering tunable single-shot doses up to ~20 Gy to millimeter-scale volumes on nanosecond timescales, equivalent to ~10⁹ Gy s⁻¹, spatially homogenized and tailored to the sample. The platform provides a unique infrastructure for translational research with protons at ultrahigh dose rates.

Florian Kroll, Florian-Emanuel Brack, Constantin Bernert, Stefan Bock, Elisabeth Bodenstein, Kerstin Brüchner, Thomas E. Cowan, Lennart Gaus, René Gebhardt, Uwe Helbig, Leonhard Karsch, Thomas Kluge, Stephan Kraft, Mechthild Krause, Elisabeth Lessmann, Umar Masood, Sebastian Meister, Josefine Metzkes-Ng, Alexej Nossula, Jörg Pawelke, Jens Pietzsch, Thomas Püschel, Marvin Reimold, Martin Rehwald, Christian Richter, Hans-Peter Schlenvoigt, Ulrich Schramm, Marvin E. P. Umlandt, Tim Ziegler, Karl Zeil, Elke Beyreuther