Biodegradable Osmium Nanoantidotes for Photothermal‐/Chemo‐ Combined Treatment and to Prevent Chemotherapy‐Induced Acute Kidney Injury

Abstract Acute kidney injury (AKI) is a common adverse event in chemotherapy patients. AKI is accompanied by the generation of reactive oxygen species (ROS) and inflammation. Therefore, the management of ROS and inflammation is a potential strategy for AKI mitigation. Herein, polyethylene glycol‐coated osmium nanozyme‐based antidotes ( Os ) are developed for imaging‐guided photothermal therapy (PTT) in combination with cisplatin ( Pt ); while, avoiding AKI induced by high‐dose Pt . Os nanoantidotes can enhance the efficiency of tumor treatment during combined PTT and chemotherapy and inhibit tumor metastasis by improving the hypoxic and inflammatory tumor microenvironment. Os nanoantidotes preferentially accumulate in the kidney because of their 2‐nm size distribution; and then, regulate inflammation by scavenging ROS and generating oxygen to alleviate Pt ‐induced AKI. Os nanoantidotes can be cleared from the kidneys by urine excretion but can be degraded under hydrogen peroxide stimulation, reducing the bio‐retention of these compounds. By integrating PTT with inflammatory regulation, Os nanoantidotes have the potential to reduce the side effects of chemotherapy, offering an alternative route for the clinical management of cancer patients with chemotherapy‐induced AKI.