No Pain, No High: Nektar’s Opioid Drug Hits Trial Goals, Lifts Shares

An experimental opioid drug from Nektar Therapeutics now has clinical trial results showing that it can relieve pain without causing a high. The news may offer a potential alternative to the addictive qualities of prescription painkillers that are fueling a nationwide opioid epidemic.

Nektar (NASDAQ: [[ticker:NKTR]]) released the Phase 3 clinical trial results today and the markets welcomed the developments. Shares in San Francisco-based Nektar were trading at $19.94 this morning, up more than 28 percent from Friday’s closing price.

The Nektar drug NKTR-181 is an opioid, but the company says it is the first in a new class of drugs developed to relieve pain without causing the euphoria associated with traditional opioids. According to Nektar, its drug is less addictive because its molecular structure is designed to cross the blood-brain barrier more slowly than other opioids. Nektar says that slowing drug’s entry rate into the brain reduces euphoric effects.

Nektar tested its opioid pill in more than 600 patients with moderate to severe, chronic low-back pain who had not previously been treated with opioids. The main goal of the study was to show a mean change in the weekly average pain score. During the open-label portion of the trial when the dose of the drug was adjusted, Nektar says, average pain scores dropped by 65 percent. After the dose was adjusted, patients then entered the double-blind, placebo-controlled portion of the trial which studied the Nektar drug over 12 weeks. Nektar says in that part of the trial, average pain scores for patients in the control arm of the trial increased more than they did in patients dosed with the NKTR-181, averaging a score of 1.46. Patients who received the Nektar drug averaged a pain score of 0.92.

The Nektar drug also hit secondary goals of the trial, measured by statistically significant scores in pain reduction. Nektar says 71.2 percent of patients who received its drug reported pain reduction greater than 30 percent, compared with 57.1 percent of those who received a placebo. In scores measuring pain reduction greater than 50 percent, Nektar says 51.1 percent of patients dosed with its drug reached that pain relief threshold compared to 37.9 percent of those in the placebo arm.

The report on Nektar’s clinical trial findings comes as abuse of prescription painkillers continues to rise. Nektar cites a 2014 survey from the Substance Abuse and Mental Health Services Administration showing nearly 2 million Americans either abused prescription opioids or were dependent on them. According to figures from the Centers for Disease Control and Prevention, nearly 22,000 deaths in 2015 involved prescription opioids.

Photo by Flickr user tr0tt3r via a Creative Commons license.

Author: Frank Vinluan

Xconomy Editor Frank Vinluan is a business journalist with experience covering technology and life sciences. Based in Raleigh, he was a staff writer at the Triangle Business Journal covering technology, biotechnology and energy before joining MedCityNews.com as North Carolina bureau chief. Prior to moving to North Carolina’s Research Triangle in 2007 he held business reporting positions at The Des Moines Register and The Seattle Times.