Avenue Therapeutics, Inc. announced that it has reached agreement with the U.S. Food and Drug Administration (FDA) on key elements of the Phase 3 safety study, including the primary endpoint and statistical analysis approach, for intravenous (IV) tramadol, which is in development for the treatment of acute post-operative pain in a medically supervised setting. The agreed upon non-inferiority study is designed to assess the theoretical risk of opioid-induced respiratory depression related to opioid stacking on IV tramadol compared to IV morphine. The study will randomize post bunionectomy patients to IV tramadol or IV morphine for pain relief administered during a 48-hour post-operative period.

Of note, IV tramadol demonstrated safety and efficacy in this same surgical model in a Phase 3 efficacy trial. Patients will have access to IV hydromorphone, a Schedule II opioid, for rescue of breakthrough pain. The primary endpoint is a composite of elements indicative of respiratory depression.

Avenue is submitting the revised protocol to the FDA including the statistical plan, which reflects the now agreed upon study design, for final review.