Our approach allows for the modification of the tumour microenvironment by taking advantage of the Hb allosteric properties and their enhancement by ITPP for a complete O2 release in order to, on the one hand, alleviate hypoxia in the pathological sites and, on the other hand, for its long‐term action on endothelial cell PTEN activation to maintain the vessels in their normal state, ensuring a prolonged blood flow efficacy. Here, PTEN is linked to neoplasm.