Avanir Pharmaceuticals has received a Complete Response letter (CRL) from the US Food and Drug Administration (FDA) to its New Drug Application (NDA) for AVP-825.

AVP-825 is an investigational drug-device combination product, which includes low-dose sumatriptan powder delivered intranasally utilizing Breath Powered delivery technology.

In the CRL, consistent with the preliminary feedback, the FDA asked the company to assess the root causes of device use errors observed in the previously conducted human factors testing.

Avanir Pharmaceuticals chief medical officer Joao Siffert said: "Following the receipt of the preliminary feedback we have been working internally and with the FDA toward implementing changes prior to repeating the human factors study.

"Based on these conversations, we will conduct a new human factors study, with input from the FDA, with a goal to respond to the CRL in the first half of calendar 2015."

According to the company, AVP-825 will be the first and only dry-powder intranasal form of sumatriptan for the treatment of migraine, if approved.

AVP-825 is not yet approved by the FDA, while sumatriptan is the most commonly prescribed migraine medication.