GW Pharmaceuticals [GWP.L] and Bayer Healthcare [BAY.F] have submitted a New Drug Submission for Sativex, a cannabis-based medicine for the symptomatic treatment of multiple sclerosis (MS) and neuropathic pain, to Health Canada. This move will help generate optimism regarding Sativex, offering renewed hope for manufacturers and patients alike.
This new form of cannabis-based analgesic, containing tetrahydrocannabinol and cannabidiol, will be indicated for the symptomatic treatment of muscle spasticity and pains associated with MS, as well as for the treatment of neuropathic pain not responding to opioid therapy. The finished product is delivered in the form of an oro-mucosal spray, and is equipped with an electronic device to facilitate accurate dosing and prevent misuse.
In November 2003, GW Pharmaceuticals announced that the UK approval of Sativex would be delayed until late 2004. This came as a blow not only to patients in the UK who hoped to see Sativex on prescription this year, but also for patients in New Zealand, since the government there stated that no decision on cannabis as a prescription drug will be made until the UK medicines authority verdict.
Furthermore, this decision raised concerns for GW regarding the launch of Sativex, but also brings into question whether the UK will approve Sativex for all the uses it originally requested. Although Sativex's approval for MS appears certain, the application to use Sativex for neuropathic pain could be rejected until more trial results are available later next year.
The submission of a NDS to Health Canada for MS and neuropathic pain will alleviate worries over the approval of this controversial medicine. Further hope can be taken from the US launch of Solvay's Marinol (dronabinol), a cannabinoid-based product for the treatment of anorexia and cachexia.
Despite the lack of strong clinical evidence for the efficacy of cannabis-based drugs for the treatment of spasticity and pain, Sativex should receive strong uptake in the MS and neuropathic pain markets due to the large patient interest. Furthermore, as Sativex treats the symptoms of MS, it will not threaten the revenues of currently marketed MS disease modifying drugs, and instead will be used as an add-on therapy.