Cephalon, Inc. announced that the data from a phase 3 clinical trial of Fentora (fentanyl buccal tablet) demonstrate efficacy in the management of breakthrough pain in opioid-tolerant patients with chronic low back pain.

In the double-blind, placebo-controlled study, statistically significant differences in pain intensity were apparent within 10 minutes and at all subsequent time points measured throughout the 120 minute assessment period. Improvement as measured on the primary endpoint (the Sum of Pain Intensity Differences at 60 minutes, SPID60) was also significant. Adverse events were typical for opioids and more frequent during the titration phase than the double-blind phase. Data from the Cephalon sponsored study will be presented at upcoming medical meetings, including a poster presentation at the annual meeting of the American Society of Regional Anesthesia and Pain Medicine, November 16-19, 2006, in San Francisco.

"The results of this study suggest that Fentora may have application beyond its current indication in cancer and provide important support to our strategy for future label expansion in breakthrough pain associated with multiple chronic pain conditions," said Dr Lesley Russell, senior vice president, Worldwide medical and regulatory operations. "In opioid-tolerant patients, we believe Fentora has the potential to address the rapid onset characteristic of breakthrough pain, a common component of low back pain." An estimated 51 per cent of people with chronic pain report back pain, making it the most common chronic pain condition, according to the American Chronic Pain Association.

Fentora was approved by the Food and Drug Administration on September 25, 2006, for the management of breakthrough pain in patients with cancer who are already receiving and who are tolerant to opioid therapy for their underlying persistent cancer pain. Its drug delivery system generates a reaction that is accompanied by transient changes in pH believed to optimise how well the tablet dissolves and how quickly the medicine passes across the lining of the cheek, or buccal mucosa. In clinical trials involving patients with cancer, Fentora was generally well tolerated; most adverse events with Fentora are typical opioid side effects and mild to moderate in severity. The most common (greater than or equal to 10 per cent) adverse events observed in clinical trials of Fentora were nausea, vomiting, application site abnormalities, fatigue, anaemia, dizziness, constipation, edema, asthenia, dehydration, and headache. No attempt was made to correct for concomitant use of around-the-clock opioids or cancer-related symptoms. The most serious adverse events associated with all opioids are respiratory depression (potentially leading to apnea or respiratory arrest), circulatory depression, hypotension, and shock. All patients should be followed for symptoms of respiratory depression. Opioid side effects should be expected and managed accordingly.