The Food and Drug Administration (FDA) has issued a complete response letter (CRL) to Avenue Therapeutics regarding the New Drug Application (NDA) for intravenous (IV) tramadol for the management of adults with moderate to moderately severe pain in a medically supervised healthcare setting.

In the CRL, the FDA stated that the NDA could not be approved in its current form because IV tramadol, which is intended to treat patients in acute pain who require an opioid, is not safe for the intended patient population. “Specifically, if a patient requires an analgesic between the first dose of IV tramadol and the onset of analgesia, a rescue analgesic would be needed. The likely choice would be another opioid, which would result in opioid ‘stacking’ and increase the likelihood of opioid-related adverse effects,” the Agency explained in the letter. Additionally, the FDA noted that adequate terminal sterilization validation was needed prior to approval.

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The NDA for IV tramadol, which was submitted in December 2019, includes data from two phase 3 clinical trials involving patients who were treated following bunionectomy or abdominoplasty, along with an open-label safety study and an epidemiology study. Findings from the phase 3 trials showed that IV tramadol met all of the primary and most of the secondary end points.

“We believe that our extensive clinical database strongly supports the value of treatment with IV tramadol as an effective alternative to intravenous Schedule II conventional opioids,” said Lucy Lu, MD, President and CEO of Avenue Therapeutics. “We will request a meeting with the FDA as soon as possible and are committed to working closely with the agency to resolve these issues in order to bring this important medicine to patients and clinicians in the US.”

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Avenue Therapeutics receives complete response letter from the FDA for IV tramadol. [press release]. New York, NY: Avenue Therapeutics; October 12, 2020.