Adynxx, Inc. announced that the first patient was dosed in a Phase 2 study of its lead product candidate, AYX1. The primary objectives of the study are to evaluate the safety and efficacy of a single, preoperative dose of AYX1 to reduce acute post-surgical pain and prevent chronic pain following surgery. There are approximately 30 million inpatient surgical procedures performed annually in the United States and more than 70% of surgery patients experience moderate or severe post-surgical pain. Of those patients, fewer than half report adequate pain relief with currently available analgesics. In addition, depending on the surgical procedure, from 10% to more than 50% of patients will go on to develop chronic post-surgical pain. Although current therapies provide short-term relief of pain at rest following surgery, these therapies have limited effect on movement-evoked pain and do not prevent chronic post-surgical pain. Attempts to treat chronic post-surgical pain often include daily dosing of opioid-based medications that are associated with multiple adverse effects. The 200-subject, eleven-center, randomized double-blind, placebo-controlled study will follow subjects for 90 days following total knee arthroplasty, with a primary endpoint of reduced pain with walking from day 7 to 28 compared to placebo.