FDA Approves Movantik for Opioid-Induced Constipation

The FDA approved naloxegol (Movantik), an oral treatment for opioid-induced constipation (OIC) in adults with chronic noncancer pain.

 

Naloxegol is a peripherally acting mu-opioid-receptor antagonist that is used to decrease the constipating effects of opioids. “Supportive-care products such as Movantik can lessen the constipating side effects of opioids,” said Julie Beitz, MD, director of the Office of Drug Evaluation III in the FDA’s Center for Drug Evaluation and Research.

 

Opioids play an important role in chronic pain relief and millions of patients are treated with them in the United States each year. They work by binding to mu-receptors in the central nervous system, but they also bind to mu-receptors in the gastrointestinal tract, which decreases the gut motility, and can result in OIC.

 

Naloxegol’s safety and effectiveness were established in two clinical trials that included 1,352 participants who had taken opioids for at least four weeks for noncancer-related pain and had OIC. Participants were randomly assigned to receive 12.5 or 25 mg of naloxegol or placebo once daily for 12 weeks. The trials were designed to measure the change in the number of bowel movements per week from the start of the study.

 

Results of the first trial showed that 44% of participants receiving 25 mg naloxegol and 41% of participants receiving 12.5 mg of the drug experienced an increase in bowel movements per week compared with 29% of participants receiving placebo. The second trial showed similar results.

 

Common side effects of naloxegol include abdominal pain, diarrhea, headache and flatulence. The FDA is requiring a postmarketing study to further evaluate the potential risk for cardiovascular adverse events in patients taking naloxegol.

Naloxegol is part of an exclusive worldwide license agreement between AstraZeneca and Nektar Therapeutics. The product was developed using Nektar’s oral small molecule polymer conjugate technology and will be distributed by AstraZeneca.