Multiple sclerosis, or MS, a chronic disease of the central nervous system, results in progressive disability in most cases. About 400,000 people in the United States and more than 2.5 million worldwide suffer from multiple sclerosis. Walking impairment is one of the onerous aspects of MS for patients. Currently, no therapies are indicated to improve walking function in MS patients.
Acorda Therapeutics Inc.'s (ACOR) Fampridine SR, which has been in development since the mid-1990s, could perhaps become the first drug to improve walking ability of MS patients, if it successfully passes muster with the FDA. Sanofi-Aventis' (SNY) Nerispirdine, which is also being evaluated as a potential treatment in improving the ability to walk in patients with multiple sclerosis, is under phase II testing.
An advisory committee of the FDA is slated to review Fampridine SR on October 14 and the regulatory agency is scheduled to make a final decision on October 22.
Fampridine-SR, an oral, sustained-release formulation of Fampridine, is a selective neuronal potassium-channel blocker that increases the ability of the nerve to conduct electrical impulses. The drug works by blocking exposed potassium channels in damaged nerve fibers that have lost their insulating sheath of myelin and restores the transmission of impulses across the nerve fibers.
Fampridine SR was licensed to Acorda by Elan Corp. plc (ELN) in February 1997. Under the agreement crafted on February 20, 1997, Elan granted Acorda, which was then a privately-held firm, exclusive, worldwide rights to develop and market Fampridine SR for spinal cord injury. Elan had then retained the rights to develop the product for multiple sclerosis and other, non-SCI (spinal cord injury) markets.
In September 2003, the existing agreement was amended and Acorda was granted exclusive, worldwide rights to Fampridine SR for all indications by Elan in return for the payment of royalties and milestones. In addition, Acorda entered into a supply agreement under which Elan provides Fampridine SR based upon an agreed upon price schedule. The same month, Acorda granted Teva a right of first negotiation for the co-development and co-promotion of Fampridine-SR in the U.S. However, Teva returned the full rights to Fampridine SR to Acorda in June 2005.
Following the failure of Fampridine SR in late-stage trials as a potential treatment for spinal cord injury in 2004, Acorda has been banking on the success of the trials evaluating Fampridine SR in improving the walking ability in patients with multiple sclerosis.
In two phase III trials that were conducted under Special Protocol Assessments from the FDA, a significantly greater proportion of people taking twice-daily dose of Fampridine SR had a consistent improvement in walking speed, the study's primary outcome, compared to people taking placebo as measured by the Timed 25-Foot Walk. The data from the two late-stage trials formed the basis for filing New Drug Application for Fampridine SR for improving walking function in MS patients in January 30, 2009.
Last week, the company announced long-term data for Fampridine SR from the first phase III extension study, which demonstrated walking speed over a two year period in a subset of people with MS.
The undesirable side effect associated with Fampridine SR as reported from the clinical trials is seizure and the FDA may take a closer look at this risk. However, J.P. Morgan analyst Geoffrey Meacham is of the view that the seizure rate is in line with what would be expected from the general multiple sclerosis population.
The FDA approval of Fampridine SR is crucial for Acorda, which has yet to report profits. If approved, analysts expect annual peak sales of $500 million for Fampridine SR. According to Ron Cohen, Acorda's CEO, the therapy is likely to cost $5,000 to $10,000 a year.
Fampridine SR has been designated an orphan drug by the FDA, allowing for seven years of market exclusivity in the U.S. The EMEA also designated Fampridine-SR as a New Active Substance, entitling the drug to 10 years of market exclusivity in Europe.
The company's only marketed drug is Zanaflex -- approved for the management of spasticity, a condition associated with multiple sclerosis. Acorda acquired rights to Zanaflex capsules and Zanaflex tablets from Elan Pharmaceuticals Inc., a subsidiary of Elan Corp. in July 2004. Zanaflex tablets were approved by the FDA in 1996 and lost compound patent protection in 2002.
Zanaflex capsules were approved by the FDA in 2002, but were never marketed by Elan. Acorda began marketing Zanaflex capsules in April 2005. Since there are pharmacokinetic differences between Zanaflex capsules and a similar dose of the tablet form, under state pharmacy laws, prescriptions written for Zanaflex capsules may not be filled by the pharmacist with Zanaflex tablets or generic tizanidine tablets, according to Acorda.
Acorda's sales of Zanaflex have increased over the years. Gross sales of Zanaflex, which were $5.92 million in 2005, increased to $26.5 million in 2006, $43.5 million in 2007 and $53.4 million in 2008. In the second-quarter ended June 30, 2009 Zanaflex sales totaled $14.75 million, up from $13.1 million in the year-ago quarter.
In order to sustain operations beyond 2010, Acorda sold overseas rights to Fampridine SR to Biogen Idec Inc. (BIIB) in July of this year and received an upfront payment of $110 million in return. Under the terms of the licensing deal with Biogen Idec, Acorda is also entitled to receive an additional $400 million, plus double-digit royalties if regulatory and sales milestones are met.
Under the existing agreement in place with Elan, which was inked way back in February 1997, 7% of the upfront and milestone payments that Acorda gets from Biogen Idec will be paid to Elan.
Acorda has had operating losses since inception and as of June 30, 2009, had an accumulated deficit of approximately $386.4 million. Net loss was $74.3 million, $38 million, and $60 million for the years ended December 31, 2008, 2007 and 2006, respectively. Net loss for the second-quarter ended June 30, 2009 widened to $23.32 million or $0.62 per share from $18.82 million or $0.58 per share in the year-ago quarter.
The company's preclinical programs include neuregulins, remyelinating antibodies and chondroitinase focused on multiple sclerosis, or MS and stem cell injury, or SCI. However, in addition to MS and SCI, the above-mentioned products are expected to be applicable across a number of Central Nervous System, or, CNS disorders, including stroke and traumatic brain injury. Acorda expects to file an Investigational New Drug Application for one of the neuregulins, GGF2 late this year.
Acorda went public in February 2006, pricing its IPO at $6 per share. The stock, which has traded in the range of $14.42 - $33 over the last twelve months, closed Friday's trade at $23.49.
Safety is a major issue for MS drugs. If Fampridine SR successfully crosses regulatory hurdles and reaches pharmacy shelves, Acorda may see an upturn in its fortunes. Stay tuned...
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