Withdrawal after Converting from Acetaminophen and Hydrocodone to the Buprenorphine Transdermal System

Tim Casey

Las Vegas—In a post-hoc analysis of a 14-day, randomized, double-blind study, researchers found that none of the patients who took acetaminophen and hydrocodone and then converted to the buprenorphine transdermal system (BTDS) experienced opioid withdrawal, as defined by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria.

The results were presented at the AAPM meeting during a poster presentation titled Evaluation of Withdrawal During Conversion of Patients from Vicodin® to the Buprenorphine Transdermal System.

In 2010, the US Food and Drug Administration approved the BTDS, which delivers 5-, 10-, or 20-mcg/hour doses of buprenorphine once weekly to patients with severe chronic pain who need a continuous opioid analgesic. Hydrocodone is the most frequently prescribed opioid in the United States and is also available in combination with acetaminophen.

Patients were eligible to participate in the trial if they were between 40 and 85 years of age, had osteoarthritis pain controlled by 15 to 30 mg of hydrocodone per day, and took ≤2 doses per day of supplemental analgesia. They could also continue to receive scheduled nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors.

During the open-label run-in period, all of the patients received acetaminophen and hydrocodone. Some patients were then randomized to receive 20 mcg/hour of the BTDS for 14 days (BTDS 20 group) or 10 mcg/hour of the BTDS with an option to take 20 mcg/hour of the BTDS (BTDS 10-20 group). The randomized group included patients who had a 0 or 1 on a 4-point daily pain scale on ≥5 days of the 7-day run-in period and used ≤2 doses per day of supplemental analgesia.

There were 101 patients in the BTDS 10-20 group and 103 patients in the BTDS 20 group. Baseline demographics were similar between the groups. The mean age was 58.2 years, and the mean weight was 97.4 kg. In addition, 67% of patients were female, 68% were white, 78% had knee osteoarthritis, and 22% had hip osteoarthritis.

The authors used the DSM-IV criteria to assess withdrawal, which is defined as patients experiencing ≥3 of the following 9 symptoms: dysphoric mood; nausea and vomiting; muscle aches; lacrimation or rhinorrhea; papillary dilation, piloerection, or sweating; diarrhea; yawning; fever; and insomnia. None of the patients met the criteria. In the BTDS 10-20 group, 12 patients had nausea and vomiting, 1 patient had muscle aches, and 3 patients had diarrhea. In the BTDS 20 group, 11 patients had nausea and vomiting, and 2 patients had diarrhea.

According to the authors, most of the treatment-emergent adverse events (AEs) were similar to those observed with opioid agonists and transdermal patches. In the BTDS 10-20 group, 53% of patients had an AE, and 10% discontinued the study because of an AE. In the BTDS 20 group, 62% of patients had an AE, and 16% discontinued the study because of an AE.

This study was sponsored by Purdue Pharma L.P.