SIGA Technologies, Inc. is a commercial-stage pharmaceutical company. The Company is focused on the development of medicines to treat and prevent infectious diseases. Its flagship product, TPOXX (tecovirimat), is an antiviral medicine approved in the United States and Canada for the treatment of smallpox and authorized in Europe, the United Kingdom, and Japan for the treatment of smallpox, monkeypox (mpox), cowpox, and vaccinia complications. TPOXX specifically inhibits the activity of a protein called VP37, found on the surface of all orthopoxviruses. This prevents the virus from leaving infected cells, slowing the spread of the infection and limiting it to a point where the immune system can clear the virus. The European Medicines Agency and United Kingdom approvals include labeling for oral tecovirimat indicating its use for the treatment of smallpox, monkeypox, cowpox, and vaccinia complications following vaccination against smallpox.