Yesterday was World MS Day, designated to raise awareness about multiple sclerosis. Sanofi launched a program to mobilize and inspire people with MS called Everyday Matters. Biogen Idec, among other things, conducted an essay competition in Japan for stories from people living with MS. Acorda Therapeutics (Nasdaq: ACOR) launched an online talk show.

Cute marketing gimmicks -- especially the talk show -- but in the big picture, none of it matters all that much for sales. Ultimately, efficacy and safety will rule.

CRABs
Teva Pharmaceuticals' (Nasdaq: TEVA) Copaxone, Rebif -- marketed by Pfizer (NYSE: PFE) and Merck KgaA -- Biogen's Avonex, and Bayer's Betaseron are the oldies-but-goodies for multiple sclerosis. They're not exceptionally effective -- they certainly don't cure MS -- but doctors will continue to use them because they do delay the progression of MS and doctors have lots of experience with them.

We should throw Novartis' (NYSE: NVS) Extavia into the mix here since it's the same drug as Betaseron sold under a different label after each pharma bought the biotechs that had rights to Betaseron.

Stratifying risk
Biogen and Elan's (NYSE: ELN) Tysabri works better than the older medications, but it has a distinct disadvantage: the potential for an often-fatal brain infection called progressive multifocal leukoencephalopathy, or PML.

Tysabri doesn't cause PML directly. That honor goes to the JC virus. Tysabri just helps the normally harmless virus do its dirty work. While keeping the immune system from attacking the patient's own cells, Tysabri also discourages the immune system from attacking the JC virus.

The JC virus is present in about half of patients. If it isn't floating around dormant in the body, it can't cause PML. So Biogen and Elan developed an assay to detect the JC virus. The assay has only been on the market for a short time, but it seems to be helping the companies capture patients earlier in their disease progression, which should help increase sales.

Needle-free
The second generation of multiple sclerosis drugs are taken orally. Novartis' Gilenya was the first on the market, but it hasn't been a hot seller because of safety concerns.

Biogen's BG-12, Teva's laquinimod, and Sanofi's teriflunomide have all completed phase 3 trials, and it looks like BG-12 is the winner. Biogen recently submitted the drug to the Food and Drug Administration, so a decision should be made near the end of the year.

Like Gilenya, I'd expect BG-12 to have a slow start. MS is a progressive disease that isn't immediately life-threatening for most patients, so there's little reason for most patients to be guinea pigs. Doctors will likely start with patients that have a strong aversion to needles to get a feel for the drug before prescribing it to a wider audience.

Walking in a class of its own
All of the drugs mentioned above work to slow down the progression of the disease, but Acorda's Ampyra works to treat one of the symptoms of the disease: problems with walking. Not every patient has that symptom, so Acorda is working with a reduced market, but it's the only drug out there to treat the symptom.

Ampyra is far from a blockbuster, but sales have been climbing steadily. Last year, sales increased 58% to $210 million. And Acorda has guided for an increase of 21% to 31% this year. And that's only for U.S. sales. Outside of the U.S., where the drug is called Fampyra, Biogen is responsible for sales and sends Acorda a royalty check.

Best bet
I think the two best plays on the multiple sclerosis market are Elan and Acorda.

I like the potential that Tysabri has as the companies stratify the risk for patients. Elan is more dependent on Tysabri than Biogen, which makes it more risky -- but potentially more lucrative. Elan has an upcoming data release for its Alzheimer's drug bapineuzumab, so the company could be a bad-news buy if that data comes up negative.

Acorda looks promising if it can keep the current sales trajectory and Biogen can push into the EU. With Acorda essentially completely dependent on Ampyra -- it has another drug, but it doesn't amount to much -- the company is a big bet on MS.

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