Phase 3 Trial of Sativex, Cannabis Extract Treatment for MS Spasticity, Opens in US
A Phase 3 trial is underway in the U.S. to assess the safety and efficacy of Sativex (nabiximols), an oral spray that contains cannabis extracts, in treating spasticity — muscle stiffness or spasms — associated with multiple sclerosis (MS).
Sativex, by GW Pharmaceuticals, is available in 25 countries — including most of Europe and Canada — as an add-on therapy for MS patients with moderate-to-severe spasticity who fail to respond to other anti-spastic treatments. It contains cannabidiol (CBD) and tetrahydrocannabinol (THC), two of the most abundant cannabinoids found in the cannabis plant.
“We are excited that the U.S. Phase 3 clinical program evaluating nabiximols in multiple sclerosis spasticity is now recruiting patients, after a delay due to COVID-19,” Justin Gover, CEO of GW, said in a press release.
“Given the rigorous studies already conducted on the medicine outside of the U.S., and positive discussions with the FDA [U.S. Food and Drug Administration], we believe that we have a clear path … [to filing for approval], potentially as soon as next year,” Gover added.
The placebo-controlled trial (NCT04203498) is expected to enroll about 446 adults with MS and spasticity. They will be randomly assigned to either Sativex treatment or a placebo, both self-administered as on oral spray in the morning and evening, up to 12 times daily, for 12 weeks.
Enrolled patients will enter a 28-day “baseline” period, recording their number of daily muscle spasms using an electronic diary, while taking their routine anti-spasticity medications. This period establishes a reference point.
They then move to 12 weeks of daily treatment or placebo, followed by a two weeks of follow-up evaluations, for total of 18 weeks (about 4.5 months).
The study’s main goal is to assess if Sativex is superior to a placebo at lowering the frequency of muscle spasms in MS patients.
According to GW and its U.S. subsidiary Greenwich Biosciences, the first enrolled patient has now completed screening and entered the study’s 28-day baseline period. U.S. trial sites, yet to be announced, and contact information is expected to be available here.
This pivotal Phase 3 trial is one of five GW is planning to launch assessing Sativex’s safety and efficacy in MS spasticity. The four other studies — three focusing on the effects of treatment on muscle tone, and one on muscle spasm frequency — are expected to open between the close of this year and mid-2021.
“Now is the ideal time to develop nabiximols in the U.S. as research shows a significant percentage of spasticity patients are today self-medicating using unapproved cannabis products to relieve their spasticity,” Gover said.
The therapy’s approval in Europe was supported by data from three Phase 3 trials, which demonstrated Sativex was well-tolerated and effectively eased MS spasticity. The medication is currently not approved for any indication in the U.S.
“There is a significant need for new treatments to address spasticity in MS patients, a challenging condition with little therapeutic innovation in decades in the United States,” said Stephen Krieger, MD, an associate professor of neurology at the Mount Sinai Hospital in New York.
“Nabiximols has the potential to be a rigorously tested and FDA-regulated cannabis-derived medicine for people living with MS. I look forward to participating as an investigator in this study which will evaluate the effect of nabiximols on the frequency of muscle spasms,” Krieger added.