The Midlands Therapeutics Review and Advisory Committee (MTRAC) has reviewed the evidence on oxycodone + naloxone combination prolonged release tablets (Targinact®) for the management of severe pain.

The Committee concluded that oxycodone/naloxone prolonged-release tablets were suitable for prescribing in primary care for patients with severe opioid responsive pain who have persistent constipation despite standard laxative treatment. The evidence for efficacy and safety is relatively weak, and it has not been compared to the standard first-line treatment of an opioid plus a laxative.

Oxycodone is an established strong opioid used for treatment of severe pain, and has the usual adverse effects of this group, including constipation. Naloxone is an opioid antagonist that is very poorly bioavailable (<3%) due to high first-pass metabolism; it can therefore block opioid receptors in the gut without significant antagonistic effect systemically. The combination has been studied in a number of controlled trials, and has been shown to be effective in relieving severe pain. It had less effect on bowel function than oxycodone alone, but was not compared with an opioid plus a standard laxative.

The Committee concluded that the combination had a low place in therapy in primary care because the standard first-line therapy is an opioid plus a laxative.

The document is available from the MTRAC website, and at time of posting is linked from their Latest News page