CeNeS announces additional clinical data supporting the potential of M6G for the treatment of post-operative pain

CeNeS Pharmaceuticals notes the recent publication of additional clinical data on its lead product morphine-6-glucuronide (M6G) by an academic group at King’s College, London. The data, which was published in the international journal ‘Anesthesiology’ (1), provides further support for the potential of M6G as a treatment for post-operative pain, focusing on its potential for administration under patient-controlled analgesia (PCA). Part of this data has been presented previously at the 4th International Symposium for Nociceptive/Neuropathic Pain, King’s College Hospital.

The study, which was a randomised, double-blind study comparing the analgesic efficacy of M6G and morphine administered by initial bolus followed by PCA in 100 patients undergoing major joint replacement. Under the PCA system, patients administer their own pain relief as and when it is needed.

The key findings of the study are:

• M6G has analgesic potency similar to that of morphine. The authors speculate that the less effective pain control observed at early time points in this study in patients on M6G could be due to the need for a large loading dose or the product’s slower onset of action.
• There were clear differences between the M6G and morphine groups in terms of respiratory depression rates. The proportion of subjects with respiratory depression was markedly higher in the morphine group (27%) compared with the M6G group (6%).
• There was significantly less sedation in the M6G group in the immediate post-operative period as well as at the end of the 24 hour study period
• 24 hours post-surgery, when the nausea rate was at its highest, 41% of patients receiving morphine experienced nausea compared with 21% of those receiving M6G. However, this difference did not reach the level of statistical significance.
• The group concludes “it (M6G) has a unique pharmacodynamic profile with a better therapeutic window than morphine. Its simple, clean pharmacokinetic characteristics make it an attractive agent for further investigation…”

Commenting on the publication, Neil Clark, Chief Executive Officer of CeNeS said, “This new data adds further support to our reported clinical trial results and our belief in the potential of M6G as a new drug for the treatment of post-operative pain with significant advantages over morphine and other opiates. We believe that the less effective pain control observed with M6G at early time points in this study is due to the low loading doses used. Our first Phase III trial clearly showed that a higher loading dose of 30mg provides effective analgesia. This higher loading dose regime will be used in our second Phase III trial, which is expected to start in the next few months. If we are successful in demonstrating the efficacy and superior side effect profile of M6G compared to morphine in this large Phase III trial, which will involve approximately 440 patients, then we will have made a significant step towards the approval of the product in Europe.”

(1) Randomized, Double-blind Study of the Analgesic Efficacy of Morphine-6-Glucuronide versus Morphine Sulfate for Postoperative Pain in Major Surgery. Anesthesiology V 102, No 4, April 2005, pp 815-821