Stella Pharma Corp is a Japan-based company mainly engaged in the therapeutic drug research and development. It is engaged in the research and development of boron drugs for boron neutron capture therapy (BNCT). BNCT is a radiation therapy that selectively destroys cancer cells by utilizing the fission reaction of B-10, which is a stable isotope of boron, and thermal neutrons with low energy. Nucleus of B-10, which is a stable isotope of boron, absorbs low-energy low-speed neutrons and immediately splits into a helium nucleus (4He nucleus (α particle)) and a lithium nuclei (7Li nuclei). When a substance containing B-10 selectively accumulates in cancer cells and is irradiated with thermal neutrons, cancer cells are selectively destroyed. Product includes steboronin (SPM-011). A phase II clinical trial is conducted for brain tumor, head and neck cancer and recurrent malignant glioma. Phase I clinical trial is started for malignant melanoma, a type of skin cancer, and angiosarcoma.