The FDA has accepted for review the New Drug Application (NDA) for a first-in-class investigational opioid, NKTR-181 (Nektar Therapeutics), for the treatment of chronic low back pain in adult patients new to opioid therapy.

NKTR-181 is a long-acting selective full mu-opioid agonist; it is not a prodrug or a reformulation of an existing opioid. This novel agent has low permeability across the blood-brain barrier, which slows its rate of entry into the brain and reduces dopamine release.

The NDA is supported by 15 studies involving 2,234 participants. These trials included opioid-naive patients with chronic low back pain (N=600), patients with noncancer pain (N=630), pharmacokinetic/pharmacodynamic studies (N=450), and human abuse potential studies vs oxycodone control.

Related Articles

The FDA has set the Prescription Drug User Fee Act target action date for May 28, 2019. 

For more information visit