Acorda CSO Andy Blight

You can add another clinical stage program for remyelination to your watch list. Acorda's early-stage drug for targeting the root cause of multiple sclerosis has cleared its first hurdle in the clinic, passing its Phase I safety challenge with a set of patient cohorts that detected none of the preliminary toxicity issues or side effects that could derail it early on.

In a two-step Phase I design, investigators used the drug--rHIgM22, in-licensed from the Mayo Clinic--in 5 small cohorts of patients who either received a range of drug doses or a placebo. The second step followed a set of 21 patients for 6 months after receiving either of the two higher doses or a placebo. Acorda ($ACOR) is still picking through some biomarker and clinical activity signposts in an effort to detect preliminary signs that the drug is doing what it's intended to do.

That wasn't enough to whet investors' appetites, though. Acorda's shares edged down this morning.

The green light Acorda's sending out today leaves the company in the opening stage of a long and complex clinical path, placing it well behind Biogen Idec ($BIIB), the leader in this field. The next step will be another Phase I safety study in relapsing MS patients to check on any potential interactions that could be of concern. That study is still being designed. Only then will the drug advance toward mid-stage work, and Acorda isn't trying to hype its progress or discount the amount of work that remains.

"If we had had a 100% cure we would be able to say, this looks very interesting," Andy Blight, the chief scientific officer at Acorda, tells FierceBiotech. But that doesn't happen in the real world of complex MS studies, he added, downplaying any expectations on drug activity at this stage and emphasizing that investigators typically see "nothing that is meaningful at this time" regarding efficacy.

The first clinical step follows Biogen Idec's mixed progress so far with its own mid-stage work. Just weeks ago the company touted progress with its remyelination drug, BIIB-033, which inhibits the LINGO-1 protein. The drug only hit the primary endpoint after factoring out the dropouts, which caused some head shaking to occur among analysts and observers. And there was a clear miss on the secondary endpoints that tried to track signs of remyelination.

Biogen, though, also knows that it's in terra incognito with this drug. In a recent interview with FierceBiotech, R&D chief Doug Williams noted that there were good reasons to believe before the study began that they would have patients dropping out of the trial early on, which is why they built in the analysis for only those patients who completed the study. Their drug finishes a study for MS in 2016. And it's no secret that Biogen Idec has put a heavy emphasis on this program as one of its next-wave drugs to look to.

"They're a few years ahead of us and have a bit more firepower than we do," says Blight with a chuckle. But there's an advantage in that as well, as researchers have a chance to learn some things from the more advanced study that could allow them to streamline their work.

MS is triggered as the myelin that protects neurons is damaged and eroded by an errant immune system attack. Current drugs hold the immune system in check.

Moses Rodriguez at the Mayo Clinic found that rHIgM22 protected oligodendrocytes--which play a big role in developing myelin--and spurred them to mend demyelination in animal models.

There's also a third drug in the industry pipeline: GlaxoSmithKline's ($GSK) GSK239512, which is testing the antihistamine approach to this disease that's been studied at UC San Francisco and elsewhere. That drug, which has received near-zero attention, wrapped a Phase II study last September, according to clinicaltrials.gov. But GSK hasn't mentioned what it found or where it's headed, and a spokesperson tells FierceBiotech that investigators are still analyzing the results.