Arch Therapeutics, Inc., together with its subsidiaries, operates as a biotechnology company in the United States. The company develops and markets products based on its AC5 self-assembling technology platform to stop bleeding and control leaking, as well as manages wounds during surgery, trauma, and interventional care or from disease. Its flagship products include AC5 advanced wound system and AC5 topical hemostat, which are intended for skin applications, such as management of complicated chronic wounds or acute surgical wounds.

The company was founded in 2006 and is based in Framingham, Massachusetts.