New Option for Opioid-Induced Constipation

The US Food and Drug Administration (FDA) has approved an oral tablet formulation for Relistor.

Relistor (methylnaltrexone bromide) is a medication used to treat opioid-induced constipation (OIC) in adult patients with chronic non-cancer pain.

Relistor was previously approved by the FDA in 2008 as an injection to be administered under the skin (subcutaneous) to treat OIC in adults with advanced illness who are receiving end-of-life (palliative) care. In 2014, Relistor was approved to treat OIC in adults with chronic non-­cancer pain.

Relistor is available as 450-milligram tablets and is to be taken by mouth once daily. For some patients, oral tablets may represent a more desirable option than the injection formulation.

Mark Baker, chief executive officer of Progenics Pharmaceuticals, said in a press release that "We expect the market to be receptive to a more convenient oral tablet formulation of Relistor's well­-established subcutaneous preparation.”

While opioids may be very effective for the treatment of pain, these medications often cause constipation. Constipation caused by opioids can be difficult to manage. This approval represents another option for patients with OIC.

Common side effects include stomach pain, diarrhea, headaches, stomach distention, excessive sweating, anxiety, muscle spasms, runny nose and chills.

Relistor is not recommended for those with known or suspected gastrointestinal obstruction or those at increased risk of recurrent obstruction.

Valeant Pharmaceuticals and Progenics expect to launch Relistor in the third quarter of this year.