By Mary Welch
Look for a third-quarter FDA filing by Neurex Corp. for its analgesic, ziconotide, following completion of a Phase III trial for patients with chronic malignant pain caused by cancer or AIDS.
The Menlo Park, Calif., company said Tuesday it ended the trial after 111 patients were enrolled. Although the study had planned to enroll 165 patients, analysis of results from 111 patients showed the drug significantly reduced pain.
Data from the study, the second Phase III trial for ziconotide, will be added to findings from the first Phase III study to support a new drug application (NDA) with the FDA in the fall.
Neurex's stock (NASDAQ:NXCO) closed Tuesday up $1.875 to $23.875, an 8.5 percent jump.
Zinconotide, formerly called SNX-111, is a synthetic peptide based on a derivative from the venom of the Conus snail. It is a neuron-specific calcium channel blocker that inhibits neurotransmitter release, preventing nerve cells from sending pain messages to the brain.
Neurex's joint venture partner, Medtronic Inc., of Minneapolis, developed an implantable pump to deliver ziconotide to the spine.
In the trial, the difference between pain reduction in the ziconotide and placebo groups was substantial, according to a preliminary analysis performed by an independent party. The findings revealed the drug treatment group had a 52 percent reduction in pain vs. 27 percent in the placebo group.
Neurex called the findings "clinically and statistically significant."
"There was a big difference in the [drug and placebo] groups," said Paul Goddard, chairman and CEO of Neurex. "These results are very preliminary compared to what the FDA requires. So it's time to start the process of cleaning up the data and putting together everything that the FDA requires. We anticipate filing by the end of the third quarter but that's a tight timeline."
In the first Phase III trial, for chronic neuropathic pain, ziconotide was found to reduce pain by 40 percent. (See BioWorld Today, Jan. 14, 1998, p. 1.) *