On September 17, 2021, Avenue Therapeutics, Inc. received an acknowledgement letter from the Office of New Drugs of the Food and Drug Administration regarding Avenue’s August 31, 2021 Formal Dispute Resolution Request (“FDRR”) concerning complete response letters issued for the New Drug Application (“NDA”) for intravenous (“IV”) tramadol. The letter stated that a response will be provided by October 28, 2021. The regulatory history of the NDA for IV tramadol, the anticipated FDRR process and other pertinent information regarding these topics were previously disclosed.