A Massachusetts pharmaceutical company is throwing in the towel on a promising experimental pain drug, after two Phase II clinical trials found the medication worked no better than a placebo.
The drug, known as Z160, is a calcium blocker that was being developed as a non-opioid treatment for low back pain and post-herpetic neuralgia, a painful neuropathic condition caused by shingles.
“Despite its promising preclinical profile, Z160 was unable to translate those results into clinical efficacy. A review of the data demonstrate that both studies were conducted in a rigorous fashion and resulted in adequate exposure of Z160, yet failed to demonstrate a difference in effect from placebo on any endpoint,” said Mark Corrigan, MD, President and CEO of Zalicus (NASDAQ: ZLCS).
“There is a significant unmet need for novel and effective non-opioid based pain therapies, and it was our sincere hope that Z160, with its novel mechanism of action, would offer the potential to provide relief to the millions of patients who suffer from chronic neuropathic pain.”
Corrigan told the Boston Business Journal that the problem with Z160 was that while “it worked like gangbusters in animals, it didn’t hold up in human trials.”
It’s the second time in a little over a year that Zalicus halted development of a new pain drug after disappointing results. In 2012, the company stopped trials of Synavive, a rheumatoid arthritis drug, after studies showed it performed no better than another drug already on the market.
Zalicus plans to continue developing another experimental pain drug, called Z944. Like Z160, it is an oral T-type calcium channel blocker, which the company hopes to develop into a new class of analgesics to treat acute and chronic pain.
Calcium blockers, which are already widely used to treat high blood pressure, could also be used to block pain by limiting the concentration of calcium entering nerve cells in the spinal cord.
Z944 has completed a small Phase I trial where it showed effectiveness in treating pain. Fifteen college-age volunteers endured a mild burn on their skin and then rated how effective the drug was at relieving pain. A Phase II trial of Z944 will begin sometime next year, according to Corrigan.
Research into non-opioid pain medicines has become more important as the Food and Drug Administration moves to reschedule Vicodin and other hydrocodone products, making them harder to get.