New data demonstrates Sativex' long-term efficacy

UK drug developer GW Pharmaceuticals says that new data from an open-label extension of a trial of its cannabinoid-based pain treatment Sativex indicate that the product is effective in controlling neuropathic pain in multiple sclerosis for at least two years. The firm also said that patients who participated in the study had not developed a tolerance to drug, a result that offsets one of the main concerns regarding the product's long-term use.

GW said that, while Sativex was generally well tolerated, side effects such as dizziness, nausea and intoxication had been observed. However, the firm added that alternative analgesic drugs, such as opioids, often elicit similar responses. The positive findings represent a change of fortune on the development of the product which has, in recent months, been the subject of efficacy concerns (Marketletters passim).