CeNeS announces successful results from its Phase IIa clinical
trial of CNS 5161 in neuropathic pain
Cambridge, UK, 8th June 2005 - CeNeS Pharmaceuticals plc (AIM: CEN)
("CeNeS" or "the Company") today announced successful results from its
Phase IIa proof of concept study of CNS 5161, its potent and selective
NMDA antagonist, in neuropathic pain. In the study, which was designed to
establish the therapeutic window of CNS 5161, the product was associated
with a clear trend to improvement in pain levels and was well tolerated
with no instances of the psychotomimetic side effects associated with
some NMDA antagonists.
The Phase IIa study was a 48-patient, European multi-centre, double blind,
cross-over, dose escalating, preliminary safety and efficacy study,
comparing a single dose of CNS 5161 to placebo in order to establish a
maximum tolerated dose of CNS 5161. Intractable chronic neuropathic pain
patients of varied aetiology (such as diabetic neuropathy and post-
traumatic neuropathy) were investigated in the study. Four escalating
dose levels (125, 250, 500 and 750 ug) of CNS 5161 were planned to be
administered by intravenous infusion over six hours, with study
continuation to each higher dose subject to a satisfactory safety review
after each cohort of 12 patients had been completed. Recruitment to the
final cohort (750ug) was not completed due to hypertensive events (high
blood pressure), an expected outcome at higher doses. There were no
psychotomimetic side effects with CNS 5161, an important finding as such
events have been associated with some NMDA antagonists, causing them to
be dropped from development. This latter finding confirms CeNeS
understanding that CNS 5161 occupies a unique position in its class.
In terms of pain relief, the study showed that 500ug of CNS 5161 was
associated with a clear trend to improvements in pain levels (measured
using a Visual Analogue Scale (VAS) ) at two, six and twelve hours after
the start of the intravenous infusion, when compared to placebo. The
results were not statistically significant as may be expected with small
group sizes (12 patients per dose group) in a proof of concept study. The
analgesic effects of CNS 5161, however, appeared to be demonstrated
predominantly in the group of patients with diabetic neuropathy. Further
analysis of the data will be carried out to nvestigate the apparent
selectivity of CNS 5161 activity to the diabetic neuropathy group.
Compared to placebo, the lowest dose of 125ug showed no effect on pain
scores whilst the 250ug dose showed an improvement in pain scores that
was most evident at 24 hours. This latter observation supports previous
clinical indings with this compound. At all dose levels, CNS 5161 was
well tolerated and demonstrated a safety profile similar to that observed
in earlier clinical studies.
Neil Clark, CEO of CeNeS, said "CeNeS is very pleased that this proof of
concept dose escalating study has successfully established a therapeutic
window for the use of CNS 5161 as a potential treatment for neuropathic
pain - a serious chronic condition which is poorly treated at present.
CeNeS will continue to analyse the data from this and previous studies in
order to plan the next steps in the clinical development of this
compound." |
