Phase II and III trials of a new cannabinoid based drug designed to treat severe cancer pain are to begin at around 40 research centres, it has been announced.

GW Pharmaceuticals and Otsuka Pharmaceutical Co said that the studies are being carried out to examine the efficacy and safety of Sativex, an oro-mucosal spray designed to relieve the pain caused by some forms of advanced cancer even if a patient is receiving opioids.

It is also hoped that the trial will help identify the dose range required to help ease cancer-related pain, which can be caused by a number of different factors including the side-effects of treatment or the pressure of tumours on nerves.

Around 336 patients who have a form of the disease that has no form of curative therapy available are expected to take part in the trials, which will involve the spray being used in addition to the pain medications the patient is already taking.

A control group will be given a placebo spray, with the trial expected to last five weeks.

Masters is a global healthcare solutions provider which can provide organisations running clinical trials with comparator medications.