MIT and collaborating teams reported polymer‑coated nanoparticles and other nanomaterials that deliver IL‑12 directly to ovarian tumor sites, enhancing responses to immune‑checkpoint inhibitors and eradicating metastatic lesions in >80% of mice in published Nature Materials studies. The designs concentrate cytokine activity in the tumor microenvironment to avoid systemic toxicity while priming durable antitumor immunity. The work showed combination regimens produced immunologic memory that protected mice against rechallenge, suggesting translational potential for metastatic ovarian cancer—a malignancy historically resistant to checkpoint blockade. Authors emphasized the engineering of surface chemistry and release kinetics to maximize tumor retention and immune activation. Preclinical efficacy and favorable local tolerance support advancing formulations toward IND‑enabling studies; developers will need to demonstrate scalable manufacturing, biodistribution, and safety to address historic cytokine toxicity concerns in human trials.