The drug SB4 suppresses the action of molecules of the so-called tumor necrosis factor alpha (TNF-α), which is associated with the development of cancer. The drug was found in the basement of a hospital in the city of Mariupol.

The hospital had been treating patients with TNF-A for more than a year, but the drug had not yet been found. It is believed that the discovery of the drug in the hospital's basement may have led to its discovery in the first place.