As filed with the Securities and Exchange Commission on February 9, 2006

Registration No. 333-128827

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

AMENDMENT NO. 7 TO
FORM S-1
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

ACORDA THERAPEUTICS, INC.
(Exact Name of Registrant as Specified in its Charter)

15 Skyline Drive
Hawthorne, New York 10532
(914) 347-4300
(Address, Including Zip Code, and Telephone Number,
Including Area Code, of Registrant's Principal Executive Offices)

Ron Cohen
Chief Executive Officer
15 Skyline Drive
Hawthorne, New York 10532
(914) 347-4300
(Name, Address, Including Zip Code, and Telephone Number,
Including Area Code, of Agent For Service)

Copy To:

        Approximate date of commencement of proposed sale to the public:    As soon as practicable after the effective date of this Registration Statement.

        If the securities being registered on this form are being offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. o

        If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

        If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

        If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

        If delivery of the prospectus is expected to be made pursuant to Rule 434 under the Securities Act, please check the following box. o

        The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, or until this registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and is not soliciting offers to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED FEBRUARY 9, 2006

Prospectus

5,500,000 Shares

Common Stock

        Acorda Therapeutics, Inc. is offering 5,500,000 shares of common stock. This is our initial public offering, and no public market currently exists for our shares. We anticipate that the initial public offering price will be between $6.00 and $7.00 per share. After the offering, the market price for our shares may be outside this range.

        We have applied to list our common stock on the Nasdaq National Market under the symbol "ACOR."

        Investing in our common stock involves a high degree of risk. See "Risk Factors" beginning on page 9.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved these securities or determined if this prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

        We have granted the underwriters the right to purchase up to 825,000 additional shares of common stock to cover any over-allotments. The underwriters can exercise this right at any time within 30 days after the offering. The underwriters expect to deliver the shares on or about                       , 2006.

Banc of America Securities LLC

                  , 2006

        You should rely only on the information contained in this prospectus. We have not, and the underwriters have not, authorized anyone to provide you with different information. We are not making offers to sell or seeking offers to buy these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information contained in this prospectus is accurate as of the date on the front of this prospectus only. Our business, financial condition, results of operations and prospects may have changed since that date.

TABLE OF CONTENTS

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SUMMARY

        This summary highlights information contained elsewhere in this prospectus. You should read the entire prospectus carefully before making an investment decision.

Overview

        We are a commercial-stage biopharmaceutical company dedicated to the identification, development and commercialization of novel therapies that improve neurological function in people with multiple sclerosis, or MS, spinal cord injury, or SCI, and other disorders of the central nervous system, or CNS. Our marketed product, Zanaflex Capsules, is FDA-approved for the management of spasticity. Our lead product candidate, Fampridine-SR, is in a Phase 3 clinical trial for the improvement of walking ability in people with MS. Our preclinical programs also target MS and SCI, as well as other CNS disorders, including stroke and traumatic brain injury.

        Approximately 650,000 people in the United States suffer from MS or SCI and the combined annual cost of treatment for these conditions exceeds $13 billion. It is estimated that a total of approximately 10 million people live with the long-term consequences of traumatic brain injury and stroke.

        Our goal is to continue to grow as a fully-integrated biopharmaceutical company by commercializing pharmaceutical products, developing our product candidates and advancing our preclinical programs for these large and underserved markets. We plan to accomplish this through our sales and marketing infrastructure, our extensive scientific and medical network, our partnerships and our clinical and management experience.

Our Product Pipeline

Zanaflex

        Our products, Zanaflex Capsules and Zanaflex tablets, are FDA-approved for the management of spasticity, a symptom of conditions such as MS and SCI that is commonly characterized by stiffness and rigidity, restriction of movement and painful muscle spasms. Zanaflex Capsules and Zanaflex tablets contain tizanidine hydrochloride, or tizanidine, one of the two leading treatments currently used for the management of spasticity. We acquired Zanaflex Capsules and Zanaflex tablets from a wholly-owned subsidiary of Elan Corporation, plc, or Elan, in July 2004. This strategic acquisition provided us with the opportunity to build a commercial infrastructure, develop sales and marketing expertise and create a foundation for future product launches, in addition to generating product revenue.

        In April 2005, we launched Zanaflex Capsules, a new capsule formulation of tizanidine. This product is protected by an issued U.S. patent. Zanaflex tablets lost compound patent protection in 2002 and both products now compete with 11 generic versions of tizanidine tablets.

        We believe that Zanaflex Capsules offer important benefits over Zanaflex tablets and generic tizanidine tablets. When taken with food, Zanaflex Capsules have a different blood absorption profile, referred to as pharmacokinetic profile, than Zanaflex tablets and generic tizanidine tablets, generally resulting in a lower level and more gradual rise of peak levels of tizanidine in a patient's blood. As a result of this different pharmacokinetic profile, Zanaflex tablets and generic tizanidine tablets are not therapeutically equivalent, or AB-rated, with Zanaflex Capsules. Therefore, under state pharmacy laws, prescriptions written for Zanaflex Capsules may not properly be filled by the pharmacist with Zanaflex tablets or generic tizanidine tablets. Zanaflex Capsules are also available in a higher dose, which gives patients and prescribers an additional choice in dosing and an opportunity to reduce the number of pills a person must take daily. In addition, people who have difficulty swallowing may find Zanaflex Capsules easier to take.

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        To support our commercialization of Zanaflex Capsules, we have established a sales and marketing infrastructure consisting of our internal specialty sales force, a contract sales force and a pharmaceutical telesales group. Our internal specialty sales force currently consists of 14 sales professionals who call on neurologists and other prescribers specializing in treating patients with conditions that involve spasticity. Members of this sales force also call on managed care organizations, pharmacists and wholesale drug distribution customers. We plan to expand our specialty sales force to approximately 30 sales professionals in the first quarter of 2006. Our contract sales force is provided by Cardinal Health PTS, LLC, or Cardinal Health, and consists of approximately 160 sales representatives who market Zanaflex Capsules to primary care physicians, on a non-exclusive basis. We also have a contract with Access Worldwide Communications to provide a small, dedicated sales force of pharmaceutical telesales professionals to contact primary care physicians, specialty physicians and pharmacists. Our current sales and marketing infrastructure enables us to reach virtually all high-volume prescribers of Zanaflex tablets and generic tizanidine. We believe that these prescribers are also potential high-volume prescribers for our lead product candidate, Fampridine-SR, if approved.

Fampridine-SR

        Fampridine-SR is currently in a Phase 3 clinical trial for the improvement of walking ability in people with MS. The trial is being conducted pursuant to a Special Protocol Assessment, or SPA, with the FDA. The FDA has agreed that, if successful, this trial could qualify as one of the pivotal efficacy studies required for drug approval. Fampridine-SR is a small molecule drug contained in a sustained release oral tablet form. Laboratory studies have shown that fampridine, the active molecule in Fampridine-SR, improves impulse conduction in nerve fibers in which the insulating outer layer, called the myelin sheath, has been damaged. This damage may be caused by the body's own immune system, in the case of MS, or by physical trauma, in the case of SCI.

        More than 800 people have been treated with Fampridine-SR in over 25 clinical trials, including nine clinical trials in MS and 11 clinical trials in SCI. In six Phase 2 clinical trials, treatment with Fampridine-SR has been associated with a variety of neurological benefits in people with MS or SCI. In our most recently completed Phase 2 clinical trial, there was a trend toward improvement in the primary endpoint of walking speed and, when analyzed using the same methodology that the FDA has now agreed to in the SPA for our Phase 3 clinical trial, these results are statistically significant. We expect the recruitment period for the current Phase 3 clinical trial, which began in June 2005, to end in February 2006. The treatment period is 14 weeks and the subjects are involved in trial procedures for approximately five months. We expect to be able to evaluate data from this clinical trial in the third quarter of 2006.

        We believe Fampridine-SR is the first potential therapy in late-stage clinical development for MS that seeks to improve the function of damaged nerve fibers, rather than only treating the symptoms of MS or slowing the progression of disease. To our knowledge, there are no current drug therapies that improve walking ability in people with MS. We plan to commercialize Fampridine-SR, if approved, ourselves in the United States, and possibly Canada, and with partners in various markets throughout the rest of the world.

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Preclinical programs

        We have three preclinical programs focused on novel approaches to repair damaged components of the CNS:

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Chondroitinase.  This program is based on the concept of breaking down the matrix of scar tissue that develops as a result of an injury to the CNS. Published research has demonstrated that this scar matrix is partly responsible for limiting the regeneration of nerve fibers in the CNS and restricting their ability to modify existing neural connections. Independent academic laboratories have also published animal studies showing that application of chondroitinase results in recovery of function following injuries to various areas of the brain or spinal cord.



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Neuregulins.  This program is based on using GGF-2, a neuregulin growth factor to stimulate remyelination, or repair of the myelin sheath. In published studies, GGF-2 has been shown to stimulate remyelination in animal models of MS and to have other effects in neural protection and repair.



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Remyelinating antibodies.  This program is based on research performed at Mayo Clinic. Studies have demonstrated the ability of this family of antibodies to stimulate remyelination in three different animal models of MS.

        We believe that all of our preclinical therapies have the potential to address conditions for which no effective treatment currently exists. In addition to applicability in MS, SCI and various other CNS disorders, we believe that our preclinical programs also may have applicability in such fields as orthopedics, cardiology, oncology and ophthalmology.

Our Strategy

        Our strategy is to continue to grow as a fully-integrated biopharmaceutical company focused on the identification, development and commercialization of a range of nervous system therapeutics. We are using our scientific and clinical expertise in MS and SCI as strategic points of access to additional CNS markets, including stroke and traumatic brain injury. Key aspects of our strategy are to:

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maximize our revenue opportunity for Zanaflex Capsules;



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complete the clinical development and obtain regulatory approval for Fampridine-SR in MS;



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leverage the commercial presence of Zanaflex Capsules for the potential market launch of Fampridine-SR;



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advance our pipeline of preclinical programs to clinical trials; and



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pursue additional alliances for approved and development-stage products.

        We have established an advisory team and network of well-recognized scientists, clinicians and opinion leaders in the fields of MS and SCI. Depending on their expertise, these advisors provide assistance in trial design, conduct clinical trials, keep us apprised of the latest scientific advances and help us identify and evaluate business development opportunities. In addition, we have recruited over 35 MS centers and 80 SCI rehabilitation centers in the United States and Canada to conduct our clinical trials. Our clinical management team has extensive experience in the areas of MS and SCI and works closely with this network.

Risks Associated with our Business

        Our business is subject to numerous risks, as more fully described in the section entitled "Risk Factors" immediately following this prospectus summary. We may be unable, for many reasons, including those that are beyond our control, to implement our current business strategy. Those reasons

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could include failure to successfully promote Zanaflex Capsules and any other future marketed products; delays in obtaining, or a failure to obtain, regulatory approval for our product candidates; and failure to maintain and to protect our proprietary intellectual property assets, among others. The information about our preclinical and clinical trials may be useful to you in evaluating our company's current stage of development and our near-term and long-term prospects; however, you should note that of the large number of drugs in development only a small percentage successfully complete the FDA regulatory approval process and are commercialized.

        We have a limited operating history and, as of September 30, 2005, had an accumulated deficit of approximately $198.5 million. We expect to incur losses for at least the next several years. We had net losses of $26.0 million and $44.7 million for the nine months ended September 30, 2005 and for the year ended December 31, 2004, respectively. We are unable to predict the extent of future losses or when we will become profitable, if at all. Even if we succeed in promoting Zanaflex Capsules and developing and commercializing one or more of our product candidates, we may never generate sufficient sales revenue to achieve and sustain profitability.

Corporate Information

        We were incorporated in 1995 as a Delaware corporation. Our principal executive offices are located at 15 Skyline Drive, Hawthorne, New York 10532. Our telephone number is (914) 347-4300. Our website is www.acorda.com. The information on our website is not part of this prospectus.

        "Acorda Therapeutics" is a registered trademark that we own and "Zanaflex" is a registered trademark that we exclusively license. We have pending U.S. trademark applications for our logo and "Zanaflex Capsules." Other trademarks, trade names and service marks used in this prospectus are the property of their respective owners.

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THE OFFERING

        The number of shares of common stock to be outstanding after this offering is based on the number of shares outstanding as of September 30, 2005 and excludes the following:

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1,816,518 shares of common stock issuable, as of September 30, 2005, upon the exercise of outstanding options and warrants to purchase our common stock, at a weighted average exercise price of $5.13 per share;



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756,620 shares of restricted stock outstanding as of September 30, 2005;



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278,339 shares of common stock issuable, as of September 30, 2005, upon the conversion of outstanding convertible promissory notes; and



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3,000,000 shares of common stock reserved for issuance under our stock option plans, including our 2006 Employee Incentive Plan adopted in January 2006.

        Unless we specifically state otherwise, all information in this prospectus, including the number of shares of common stock to be outstanding after this offering:

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assumes the conversion of all outstanding shares of our convertible preferred stock and mandatorily redeemable convertible preferred stock into 13,338,279 shares of our common stock upon the closing of this offering;



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assumes no exercise by the underwriters of their over-allotment option to purchase up to 825,000 additional shares; and



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gives effect to the 1-for-1.3 reverse stock split of our common stock on January 11, 2006.

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SUMMARY CONSOLIDATED FINANCIAL DATA

        The following table presents a summary of our historical financial information. You should read this information in conjunction with our consolidated financial statements and related notes and the information under "Selected Consolidated Financial Data" and "Management's Discussion and Analysis of Financial Condition and Results of Operations" included elsewhere in this prospectus. We changed our fiscal year end from June 30 to December 31, beginning with the six months ended December 31, 2003.

        Pro forma amounts in the following table reflect the conversion of our outstanding convertible and mandatorily redeemable convertible preferred stock into 13,338,279 shares of common stock on the closing of this offering, assuming that shares of our preferred stock were outstanding for the entire periods presented.

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        The following table sets forth our cash, cash equivalents and short-term investments and capitalization as of September 30, 2005:

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on an actual basis giving retroactive effect to the 1-for-1.3 reverse stock split on January 11, 2006;



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on a pro forma basis to reflect:



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our entry into a revenue interest assignment arrangement with an affiliate of Paul Royalty Fund, or PRF, on December 23, 2005, including (i) our receipt at signing of a payment in the amount of $15.0 million, (ii) our use of approximately $3.0 million of that payment to repay a portion of the amount we owe to GE Capital and approximately $700,000 of that payment to pay fees and expenses related to the transaction, including expenses incurred by PRF, (iii) our recognition of a revenue interest liability of approximately $14.6 million, (iv) our recognition of a put/call option liability of approximately $400,000, and (v) our capitalization of approximately $500,000 in fees and expenses related to the transaction; and



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the automatic conversion of all of our outstanding convertible preferred stock and mandatorily redeemable convertible preferred stock into 13,338,279 shares of common stock on the closing of this offering; and



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on a pro forma basis as adjusted to reflect our receipt of net proceeds from the sale of shares of common stock in this offering at an assumed initial public offering price of $6.50 per share (the midpoint of the estimated price range shown on the cover of this prospectus), after deducting underwriting discounts and commissions and estimated offering expenses of $4.6 million.

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RISK FACTORS

        An investment in our common stock involves a high degree of risk. You should consider carefully the following risk factors and the other information contained in this prospectus before you decide to purchase our common stock. Additional risks that are not currently known or foreseeable to us may materialize at a future date. The trading price of our common stock could decline if any of these risks or uncertainties occur and you might lose all or part of your investment.

Risks Related To Our Business

We have a history of operating losses and we expect to continue to incur losses and may never be profitable.

        As of September 30, 2005, we had an accumulated deficit of approximately $198.5 million. We had net losses of $26.0 million and $44.7 million for the nine months ended September 30, 2005, and the year ended December 31, 2004, respectively. We have had operating losses since inception as a result of our significant clinical development, research and development, general and administrative, sales and marketing and business development expenses. We expect to incur losses for at least the next several years as we expand our sales and marketing capabilities and continue our clinical trials and research and development activities.

        Our prospects for achieving profitability will depend primarily on how successful we are in executing our business plan to:

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market and sell Zanaflex Capsules;



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obtain FDA approval for and commercialize Fampridine-SR;



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continue to develop our preclinical product candidates and advance them into clinical trials; and



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enter into strategic partnerships and collaboration arrangements related to our drug discovery programs and product candidates.

        If we are not successful in executing our business plan, we may never achieve or may not sustain profitability.

We will be substantially dependent on sales of one product, Zanaflex Capsules, to generate revenue for the foreseeable future.

        We currently derive substantially all of our revenue from the sale of Zanaflex Capsules and Zanaflex tablets, which are our only FDA-approved products. Although we currently distribute Zanaflex tablets, our marketing efforts are focused on Zanaflex Capsules and we do not, and do not intend to, actively promote Zanaflex tablets. As a result, prescriptions for Zanaflex tablets have declined and we expect that they will continue to decline. Our goal is to convert sales of Zanaflex tablets and generic tizanidine tablets to sales of Zanaflex Capsules. We believe that sales of Zanaflex Capsules will constitute a significant portion of our total revenue for the foreseeable future. If we are unable to convert tablet sales to capsule sales or are otherwise unable to increase our revenue from the sale of this product, our business, financial condition and results of operations could be adversely affected.

If we are unable to successfully differentiate Zanaflex Capsules from both Zanaflex tablets and generic tizanidine tablets we may not be able to increase sales of Zanaflex Capsules.

        There are currently 11 generic versions of tizanidine tablets on the market and they are significantly cheaper than either Zanaflex Capsules or Zanaflex tablets. In 2004, these generic versions of tizanidine tablets constituted 95% of tizanidine sales in the United States. Although Zanaflex Capsules have a different pharmacokinetic profile when taken with food and are available in a higher dose than Zanaflex tablets and their generic equivalents, we may be unsuccessful in convincing prescribers, patients and third-party payors that these differences justify the higher price of Zanaflex Capsules. Prescribers may prescribe generic tizanidine tablets instead of Zanaflex Capsules, and third-party payors may establish unfavorable reimbursement policies for Zanaflex Capsules or otherwise seek to encourage patients and prescribers to use generic tizanidine tablets instead of Zanaflex Capsules. In

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addition, although the FDA has determined that neither Zanaflex tablets nor generic tizanidine tablets are therapeutically equivalent, or "AB-rated," to Zanaflex Capsules, it is possible that pharmacists may improperly fill prescriptions with generic tizanidine tablets or may seek to influence patients or physicians to change prescriptions from Zanaflex Capsules to generic tizanidine tablets. If we are unable to successfully differentiate Zanaflex Capsules from Zanaflex tablets and generic tizanidine tablets in the minds of prescribers, pharmacists, patients and third-party payors, our ability to generate meaningful revenue from this product will be adversely affected.

Our company has limited sales and marketing experience and we may not be successful in building an effective sales and marketing organization to market Zanaflex Capsules to specialty physicians.

        As a company, we have limited sales and marketing experience, having only launched Zanaflex Capsules in April 2005. In order to successfully commercialize Zanaflex Capsules or any other products that we may bring to market, we will need to have adequate sales, marketing and distribution capabilities. Although we plan to expand our internal specialty sales force of 14 persons to approximately 30 persons in the first quarter of 2006, we may need to further expand that sales force in the future. We may not be able to attract and train skilled sales and marketing personnel, in a timely manner or at all, or integrate and manage a growing sales and marketing organization.

Returns of Zanaflex tablets may adversely affect our results of operations.

        Prior to the launch of generic tizanidine tablets in June 2002, wholesalers established larger than normal inventories of Zanaflex tablets. These inventories had expiration dates that extended to June 2005. Our return policy is to accept returns for six months before and 12 months after the product's expiration date. According to our Zanaflex asset purchase agreement with Elan, we are responsible for all returns of Zanaflex tablets after January 17, 2005. Zanaflex tablets sold by Elan can be returned to us through June 2006. In the year ended December 31, 2004, we took a $4.1 million charge to establish a reserve for expected returns of Zanaflex tablets sold by Elan. This charge is an estimate. If returns for products not sold by us are higher than we have estimated, we will have to record additional charges, which will adversely affect our results of operations.

Our product candidates must undergo rigorous clinical testing, the results of which are uncertain and could substantially delay or prevent us from bringing them to market.

        Before we can obtain regulatory approval for a product candidate, we must undertake extensive clinical testing in humans to demonstrate safety and efficacy to the satisfaction of the FDA and other regulatory agencies. Clinical trials of new product candidates sufficient to obtain regulatory marketing approval are expensive and take years to complete, and the outcome of such trials is uncertain.

        Clinical development of any product candidate that we determine to take into clinical trials may be curtailed, redirected, delayed or eliminated at any time for some or all of the following reasons:

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negative or ambiguous results regarding the efficacy of the product candidate;



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undesirable side effects that delay or extend the trials, or other unforeseen or undesirable safety issues that make the product candidate not medically or commercially viable;



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inability to locate, recruit and qualify a sufficient number of patients for our trials;



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difficulty in determining meaningful end points or other measurements of success in our clinical trials;



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regulatory delays or other regulatory actions, including changes in regulatory requirements;



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difficulties in obtaining sufficient quantities of the product candidate manufactured under current good manufacturing practices;



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delays, suspension or termination of the trials imposed by us, an independent institutional review board for a clinical trial site, or clinical holds placed upon the trials by the FDA;



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FDA approval of new drugs that are more effective than our product candidates;

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change in the focus of our development efforts or a re-evaluation of our clinical development strategy; and



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a change in our financial position.

        A delay in or termination of any of our clinical development programs could have an adverse effect on our business.

If our Phase 3 clinical trials of Fampridine-SR are unsuccessful, or if we are unable to obtain regulatory approval for this product candidate or any approval is unduly limited in scope, our business prospects will be adversely affected.

        In June 2005, we initiated a Phase 3 clinical trial for Fampridine-SR for the improvement of walking ability in patients with MS. In April 2004, we released results from a Phase 2 clinical trial designed to assess the relative safety and efficacy of varying doses of Fampridine-SR in MS. Our results did not reach statistical significance for the primary endpoint in this trial. Although we have designed the current Phase 3 clinical trial to address the difficulties we encountered in interpreting the patient data from the earlier trial, we cannot be sure that the results from our current clinical trial will be statistically significant.

        To achieve the primary endpoint in our current Phase 3 clinical trial for MS, we need to show statistical improvement in the walking speed of the patients in the trial and that this improvement is both sustained and clinically meaningful to these patients. If we fail to achieve the primary endpoint in this clinical trial or the results are ambiguous, we will have to determine whether to re-design our MS trial and protocols and continue with additional testing, or cease development activities in this area. Redesigning the program could be extremely costly and time-consuming. Even if we are able to achieve the primary endpoint, we will need positive results from at least one other clinical trial to support the filing of a new drug application, or NDA, with the FDA. We cannot predict how long the second trial, or any additional trial that might be required by the FDA, will take or what the cost will be.

        Our Phase 3 clinical trial for Fampridine-SR in MS is being conducted pursuant to a special protocol assessment, or SPA, with the FDA and the FDA has agreed that, if successful, this trial could qualify as one of the pivotal trials needed to support regulatory approval. This SPA may not be changed by either us or the FDA. However, if the FDA determines that a substantial scientific issue essential to determining the safety or efficacy of Fampridine-SR is identified after the trial began, the FDA may alter its conclusion on the adequacy of the protocol. In addition, even if the SPA remains in place and the trial meets its primary endpoint, the FDA could determine that the overall balance of risks and benefits for Fampridine-SR is not adequate to support approval, or only justifies approval for a narrow set of uses or approval with restricted distribution or other burdensome post-approval requirements and limitations. If the FDA denies approval of Fampridine-SR in MS, FDA approval is substantially delayed, approval is granted on a narrow basis or with restricted distribution or other burdensome post-approval requirements, or if the Fampridine-SR program is terminated, our business prospects will be adversely affected.

        In March 2004, we completed two Phase 3 clinical trials of Fampridine-SR in SCI in which our results failed to reach their primary endpoints. We expect to resume development of Fampridine-SR for SCI after we have completed further development of the drug for MS. We cannot predict whether future clinical trials of Fampridine-SR in SCI will achieve their primary endpoints, how long these clinical trials will take or how much they will cost.

Our other drug development programs are in early stages of development and may never be commercialized.

        All of our development programs other than Fampridine-SR are in the preclinical phase. Our future success depends, in part, on our ability to select promising product candidates, complete preclinical development of these product candidates and advance them to clinical trials. These product candidates will require significant development, preclinical studies and clinical trials, regulatory clearances and substantial additional investment before they can be commercialized.

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        Our preclinical programs may not lead to commercially viable products for several reasons. For example, we may fail to identify promising pr