The U.S. Food and Drug Administration (FDA) has filed and accepted for review the New Drug Application (NDA) for NKTR-181 for the treatment of chronic low back pain in adult patients new to opioid therapy, announced Nektar Therapeutics.
NKTR-181 is a new molecular entity (NME) and the first analgesic opioid molecule to exhibit a low incidence of specific CNS-mediated side effects, such as euphoria, through the targeted alteration of brain-entry kinetics. It 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. In addition, NKTR-181 has a 14-hour elimination half-life to enable twice-daily dosing for pain control.
Nektar’s NDA submission is supported by extensive clinical and nonclinical data. The clinical data submitted in the NDA comprised 15 studies in 2,234 subjects and includes a 600-patient efficacy study in patients with chronic low back pain who are new to opioid therapy; a 630-patient long-term 52-week safety study in patients with noncancer pain, who are new to opioid therapy, as well as those who are experienced with opioid therapy; pharmacokinetic/ pharmacodynamic studies in over 450 subjects; and two human abuse potential studies evaluating both therapeutic and supratherapeutic doses of NKTR-181 versus an oxycodone control in recreational drug users.
NKTR-181 is an investigational medicine and has not been approved by the FDA or any other regulatory agencies. While the NDA submission for NKTR-181 has been accepted for review by the FDA, such acceptance does not mean that NKTR-181 will be approved by the FDA.
Low back pain is considered to be chronic if the pain has its presence for greater than three months. Chronic low back pain may initiate from an injury, disease or stress on different structures of the body. The type of pain may vary greatly and may be felt as bone pain, nerve pain or muscle pain.