CAMBRIDGE, England, 4th May 2007 - CeNeS Pharmaceuticals plc (LSE: CEN), the Cambridge based biopharmaceutical company, notes the publication of an independent study in the respected scientific journal 'Synapse'* on its Phase II NMDA antagonist, CNS 5161. CeNeS is developing CNS 5161 as a potential treatment for neuropathic pain. The independent study builds on the work that CeNeS has already undertaken with CNS 5161.
In the study reported in 'Synapse', Dr Anat Biegon and her group at the Brookhaven National Laboratory, New York, USA, have studied a radioactively labelled version of CNS 5161. They have shown that CNS 5161 is a selective and high affinity NMDA receptor antagonist with preferential binding to the activated form of the receptor. The group also demonstrated that CNS 5161 penetrates the brain well and can be used to label selectively brain NMDA receptors in vivo. Dr Biegon proposes that a radioactive form of CNS 5161 may be used as an agent to monitor NMDA receptors in the human brain using Positron Emission Tomography ("PET") and notes that "the significance of a selective, validated radiopharmaceutical agent suitable for detecting widespread as well as highly localized changes in the NMDA receptor in the living brain cannot be exaggerated".
Data from Phase I and Phase IIa studies previously carried out by CeNeS have shown that CNS 5161 has analgesic properties in patients with neuropathic pain, but does not induce the severe psychotomimetic side-effects associated with other NMDA antagonists.
Neil Clark, Chief Executive of CeNeS, said:
"The data published in this paper supports and extends our original findings with CNS 5161. It has proved very difficult to develop a PET agent with the properties that make it possible to monitor NMDA receptor activation in the human brain. The profile of CNS 5161 as a selective, high affinity and brain-penetrating agent now make this a possibility. These properties of CNS 5161, together with its low liability to induce side-effects, are the scientific foundation for our clinical development programme of CNS 5161 as a novel treatment for the major neuropathic pain market. We plan to test CNS 5161 in further Phase II trials in cancer pain and neuropathic pain later this year."
*In vitro and in vivo characterization of [3H]CNS-5161. A use-dependent ligand for the N-methyl-d-aspartate receptor in rat brain. Biegon et al., Synapse, volume 61, pages 577-586, 2007.
For more information please contact: CeNeS Pharmaceuticals plc Neil Clark, CEO Tel: +44 (0)1223 266 466
JM Finn Geoff Nash Tel: +44(0) 207 628 9688
Financial Dynamics Ben Brewerton/Emma Thompson Tel: + 44 (0) 207 831 3113
About CeNeS Pharmaceuticals CeNeS is a biopharmaceutical company specialising in the development and commercialisation of drugs for pain control, sedation and other CNS disorders such as Parkinson's disease. The company is based in Cambridge, England. For further information visit the CeNeS web site: www.cenes.com
About CNS 5161 A range of primary diseases or conditions such as diabetes, cancer, HIV/Aids and shingles, or surgical procedures such as limb amputation can result in nerve damage which leads to a sustained chronic pain. This neuropathic pain is difficult to treat as traditional analgesics do not provide adequate relief for many patients. Drug treatments for neuropathic pain represent a significant area of unmet medical need and a growing market opportunity that is currently valued at over $2 billion globally. Glutamate (particularly NMDA) receptors have been implicated in the induction and maintenance of neuropathic pain and NMDA antagonists may represent a class of drugs for effective relief of neuropathic pain. CNS 5161 is a blocker of the NMDA ion channel and has completed Phase I and more recently Phase IIa proof of c oncept clinical trials as a novel compound for the treatment of neuropathic pain. Two Phase I studies using CNS 5161 administered intravenously have been completed in male volunteers. The first study demonstrated the safety and tolerability of selected doses of CNS 5161 and the second that at a dose of CNS 5161 that was well tolerated, analgesic effects were evident in an experimental model of pain. Two phase IIa studies have been completed giving single dose intravenous infusions of CNS 5161 to patients with long standing intractable neuropathic pain. A total of 48 patients have received CNS 5161; 10 patients in an initial study and 38 patients in a study completed in 2005. Both studies reported analgesic effects of CNS 5161 at doses that were well tolerated by the patients.