Adynxx announced positive results from a Phase 2 dose-ranging clinical study of its lead product candidate, AYX1. AYX1 is under development for the reduction of acute pain and the prevention of 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 standard of care. Depending on the surgical procedure, 10 to 50% of patients will go on to develop chronic pain after major surgery. More than 50 million people in the US suffer from chronic pain, and more than 15% of those cases are a result of surgery or trauma. The 120 subject, multi-center, double-blind, placebo-controlled study followed subjects for 42 days after knee replacement surgery, with patients receiving standard of care pain management plus either a single preoperative intrathecal injection of AYX1 or placebo.

AYX1 demonstrated a statistically significant difference and clinically meaningful reduction in pain with walking from day 7 to 28 compared to placebo, the primary post-discharge endpoint. The treatment effect was sustained through the 42-day study period, highlighting the unique pain-modifying properties of AYX1. AYX1 also demonstrated a statistically significant difference and clinically meaningful reduction in pain at rest from day 7 to 28, a key secondary endpoint, similarly maintained through the 42-day study period.

Consistent with prior trials, AYX1 had an excellent safety profile and the adverse-event rate observed during the trial was typical for a population undergoing knee replacement.