Natural killer cells (also known as NK cells) are white blood cells that are a component of the innate immune system. In their cytoplasm, NK cells contain small granules with special proteins that allow them to induce apoptosis and thus kill tumor cells and virally infected cells. During apoptosis, viral units are also destroyed. As cytotoxic immune cells may be functionally exhausted during COVID-19, there is ground to believe that immunotherapy with NK cells can improve the outcomes in patients with this disease .
Celularity Inc. started a Phase 1/2 clinical study of human placental hematopoietic stem cell-derived natural killer cells (CYNK-001) for the treatment of adults with COVID-19 in 86 participants . The study is aimed at testing NK application for safety and efficacy. The estimated primary completion date is November 30, 2020, while full results are expected in November 2021.