NEW YORK (CNN/Money) -
A cannabis-based painkiller for sufferers of multiple sclerosis is expected to be in Canadian pharmacies this summer, but whether it appears on U.S. pharmacy shelves is a key question.
Sativex, which is sprayed into patients' mouths, is produced by the British firm GW Pharmaceuticals. It was approved by the Canadian government on April 19.
"A great number of multiple sclerosis sufferers have experimented, sometimes illegally, with herbal marijuana in the past," said Mark Rogerson, spokesman for GW Pharmaceuticals, whose scientists extract cannabis from greenhouse-cultivated plants. "We are confident that many patients will prefer a pharmaceutical or a scientific solution to the problem rather than crude herbal marijuana."
The manufacturer has partnered with Bayer, the German drug giant, to get Sativex to the Canadian market as quickly as possible. Bayer (up $0.98 to $32.25, Research) also has a contract to market the drug in the United Kingdom, where it is awaiting approval by British authorities.
"Also this year, we are beginning the process of seeking approval for a medicine in the U.S.," says Rogerson. "We are in the early stages of talking to the U.S. administration."
Rogerson said his company would also be seeking approval in continental Europe. "If you get your approval in one EU country then you hit the ground running in other EU countries," said Rogerson.
In the United States, there are 400,000 people diagnosed with multiple sclerosis, compared to 50,000 in Canada and about 85,000 in Britain. Roughly half of these people suffer neuropathic pain that could be treated by Sativex, according to the companies.
'This is a very important opportunity for us," said Doug Grant, spokesman for Bayer Canada who declined to provide sales estimates. "There are very few opportunities where you can provide a drug where there is no other treatment available. There's no specific drug on the market for treating neuropathic pain for multiple sclerosis."
The first legal hurdle was cleared in 2001, when Canadian regulators approved medicinal marijuana for patients with multiple sclerosis, spinal injuries, AIDS, cancer and any terminal illness with a prognosis of less than 12 months to live.
But if the past is any indication, the U.S. Food and Drug Administration might go tough on a cannabis-based drug.
"Generally, physicians do not like to use narcotic-based drugs or drugs that have addictive-type characteristics for treatment of chronic pain," said Dr. John Richert, vice president for research and clinical programs for the National Multiple Sclerosis Society.
"There is not yet solid scientific evidence that the cannabis-related drugs are useful for multiple sclerosis pain," he said. "I think if there were solid scientific evidence that this type of drug helped, then that would be the evidence for the FDA to consider in their evaluation for the drug."
More than 10 states in the U.S. have approved legislation supporting the use of medicinal marijuana. But the federal government supersedes all state legislation and the FDA lists marijuana as an illegal narcotic.
GW Pharmaceuticals hopes the FDA will see Sativex differently from its recreational cousin. In addition to multiple sclerosis, Rogerson said, the painkiller is also being tested to treat rheumatoid arthritis, spasticity, spinal injuries and bladder dysfunction.
And unlike the herbal version of marijuana, Rogerson said Sativex is sprayed into the mouth in a liquid form and poses no threat to the lungs.
"Smoking is bad for you," said Rogerson. "You don't have to take my word for that. Just look a package of cigarettes and see what it says. We don't regard smoking as an acceptable method of delivery for a medicine."
Sativex differs from Marinol, an FDA-approved drug containing the active ingredient found in marijuana, because Sativex is extracted from a plant while Marinol is synthetic. Marinol is taken as a pill to fight appetite loss by patients with HIV or cancer patients undergoing chemotherapy.