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As filed with the Securities and Exchange Commission on April 14, 2004

Registration No. 333-112676

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT NO. 3

to

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

CORCEPT THERAPEUTICS INCORPORATED

(Exact Name of Corporation as Specified in Its Charter)

Corcept Therapeutics Incorporated

275 Middlefield Road, Suite A

Menlo Park, CA 94025

(650) 327-3270

(Address, including zip code, and telephone number, including area code, of Registrant’s principal executive offices)

Joseph K. Belanoff, M.D.

Chief Executive Officer

Corcept Therapeutics Incorporated

275 Middlefield Road, Suite A

Menlo Park, CA 94025

(650) 327-3270

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

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

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

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act of 1933, please check the following box and list the Securities Act registration number of the earlier effective registration statement for the same offering:  ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act of 1933, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act of 1933, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ¨

If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box:  ¨

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 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE SECURITIES AND EXCHANGE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(A), MAY DETERMINE.

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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 an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED APRIL 14, 2004

5,000,000 Shares

Common Stock

Corcept Therapeutics Incorporated is selling 5,000,000 shares of our common stock. The underwriters have a 30-day option to purchase up to an additional 750,000 shares from us, the selling stockholder, or both, to cover over-allotments, if any. We will not receive any proceeds from the sale of any shares sold by the selling stockholder.

This is an initial public offering of our common stock. We currently expect the initial public offering price to be $12.00 per share. Our common stock has been approved for quotation on the Nasdaq National Market under the symbol “CORT”.

INVESTING IN OUR COMMON STOCK INVOLVES RISKS. SEE “ RISK FACTORS” BEGINNING ON PAGE 6.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

Legg Mason Wood Walker

Incorporated 

The date of this prospectus is             , 2004

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You should rely only on the information contained in this prospectus. We have not, and the underwriters have not, authorized any other person to provide you with different information. This prospectus is not an offer to sell, nor is it seeking an offer to buy, these securities in any state where the offer or sale is not permitted. The information in this prospectus is complete and accurate as of the date on the front cover, but the information may have changed since that date.

In this prospectus, “Corcept,” “we,” “us” and “our” refer to Corcept Therapeutics Incorporated.

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PROSPECTUS SUMMARY

The items in the following summary are described in more detail later in this prospectus. This summary provides an overview of the key aspects of this offering and does not contain all of the information you should consider. Therefore, you should also read the more detailed information set out in this prospectus, the financial statements and the other information contained in this prospectus.

Overview

We are a pharmaceutical company engaged in the development of drugs for the treatment of severe psychiatric and neurological diseases. Our lead product candidate, CORLUX^™, is currently in Phase III clinical trials and has been granted “fast track” status by the FDA for the treatment of the psychotic features of psychotic major depression, a disorder that affects approximately three million people in the United States each year and for which there are no FDA-approved treatments. We have also initiated a clinical study to evaluate the tolerability and efficacy of CORLUX in improving cognition in patients with mild to moderate Alzheimer’s disease.

Market Opportunity

Psychotic major depression, or PMD, is a serious psychiatric disorder that is more prevalent than either schizophrenia or manic depressive illness. The disorder is characterized by severe depression accompanied by psychosis. Psychosis is delusional thinking, hallucinations or both. PMD is not a simple combination of psychosis and depression, but rather a complex interaction between a predisposition to become psychotic and a predisposition to become severely depressed. People with PMD are approximately 70 times more likely to commit suicide in their lifetime than the rest of the general population.

There is no treatment for PMD approved by the FDA. However, there are two treatment approaches currently used by psychiatrists: electroconvulsive therapy, or ECT, and combination drug therapy. Both of these approaches can have debilitating side effects. Even using these approaches, PMD patients often require lengthy and expensive hospital stays. Of the two approaches, ECT is generally considered more effective.

ECT involves passing an electrical current through the brain until the patient has a seizure. ECT requires the use of an operating room as well as the participation of a psychiatrist, an anesthesiologist and a nurse. General anesthesia and paralytic agents are necessary to avoid fractures of the spine that otherwise could result from the seizures caused by ECT. Although ECT can reduce depressive and psychotic symptoms, the procedure can result in cognitive impairment including permanent memory loss, cardiovascular complications, headache, muscle ache and nausea. In addition, complications can arise from general anesthesia. At least 100,000 patients receive ECT each year in the United States, with each patient requiring approximately six to twelve procedures over a period of three to five weeks.

Combination drug therapy involves the simultaneous administration of antidepressant and antipsychotic medications. Combination drug therapy is not as effective as ECT in relieving the symptoms of PMD and often requires three or more weeks before patients show improvement in their condition. In addition, combination drug therapy is associated with significant side effects, including weight gain, diabetes, sedation, permanent movement disorders and sexual dysfunction.

CORLUX for the Treatment of PMD

CORLUX, also known as mifepristone, works by selectively blocking the binding of cortisol, a steroid hormone, to one of its two known receptors. Elevated levels and abnormal release patterns of cortisol have been implicated in a broad range of human disorders, including PMD. We have an exclusive license to a method of use patent covering the use of CORLUX for the treatment of the

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psychotic features of PMD. By modifying the level and release pattern of cortisol within the human body, we believe that CORLUX will be able to treat the psychotic features of PMD more quickly and effectively and with fewer side effects than is possible with currently available treatments. We have not submitted a New Drug Application, or NDA, to market CORLUX and we have no other commercially available products. We have no revenues and have incurred significant losses in each year of our operations.

In January 2001, we completed a dose finding clinical trial evaluating the efficacy, tolerability and dose response of CORLUX for the treatment of the psychotic features of PMD. After one week of treatment, approximately two-thirds of the patients in the two higher dosage groups experienced clinically meaningful reductions in psychosis, as measured by a widely-used psychiatric rating scale, the BPRS. A clinically meaningful reduction in psychosis represents a reduction of symptoms that are readily recognizable by patients and physicians.

Based on the encouraging results from our dose finding trial, we initiated two clinical trials designed to evaluate the safety and efficacy of CORLUX for the treatment of PMD. The two trials, which we call the ’02 study and ’03 study, were double-blind, placebo-controlled safety and efficacy studies in which a total of 429 patients were enrolled. The ’02 study showed that CORLUX was well tolerated and that there were no discernable problems with drug interactions between CORLUX and commonly prescribed antipsychotic and antidepressant medications. The ’03 study demonstrated with statistical significance (p value = 0.01) that patients in the CORLUX group were more likely to achieve a rapid and sustained reduction in psychotic symptoms than patients in the control group, as measured by a 30% reduction in the BPRS at 7 days sustained to 28 days. The ’03 study also showed with statistical significance (p value = 0.01) that patients in the CORLUX group were more likely than patients in the placebo group to achieve a 50% reduction in the BPRS positive symptom subscale at day 7 sustained to day 28. The term “p value” is a statistical term that indicates the probability that an observed result is random. A p value of 0.05 or less is considered statistically significant.

In our fourth trial, we evaluated the safety of retreatment in patients with a favorable response to treatment in the ’02 and ’03 studies, and our analysis indicates that patients tolerated their retreatment well. Although the results of the ’03 study were favorable, the FDA will determine, upon our filing of an NDA, whether CORLUX is sufficiently safe and effective to warrant marketing approval.

We do not expect that the results of the ’02 and ’03 studies will be sufficient for them to be considered as pivotal clinical trials by the FDA. We plan to initiate two pivotal clinical trials to support an NDA to market CORLUX in the United States. We expect these two pivotal trials to be completed in the first half of 2006. We submitted protocols for our two pivotal clinical studies to the FDA for a special protocol assessment in March 2004. These clinical trials may not, however, ultimately show that CORLUX is safe and effective.

Alzheimer’s Program

Alzheimer’s disease is the most common form of dementia, accounting for approximately 50% of patients in the United States with progressive cognitive decline. More than 3.5 million people in the United States have Alzheimer’s disease. With the aging of the population, this number continues to grow each year. Published studies have suggested that higher cortisol levels are associated with a more rapid decline in Alzheimer’s patients.

We are conducting a clinical trial designed to demonstrate whether or not CORLUX will improve cognition in Alzheimer’s patients. This is the first clinical trial conducted by us in Alzheimer’s disease using CORLUX. The primary objective of this study is to assess the efficacy and tolerability of CORLUX in these patients. The study is a randomized, double-blind, parallel group comparison of the effects of CORLUX and placebo.

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GR-II Antagonist Platform

We believe that CORLUX exerts its effects by blocking the action of cortisol at one of its two known receptors, known as the GR-II receptor. A receptor is a structure that accepts a chemical messenger and creates a signal for biologic action. We also believe that elevated levels and abnormal release patterns of cortisol are involved in several other psychiatric and neurological diseases. We have assembled a patent portfolio covering the treatment of psychiatric and neurological disorders that may benefit from drugs that block, or antagonize, the GR-II receptor. In addition to PMD, we own or have exclusively licensed issued patents for the use of GR-II antagonists to treat other disorders, including early dementia, mild cognitive impairment, psychosis associated with cocaine addiction and weight gain following treatment with antipsychotic medication. We also have patent applications filed for the use of GR-II antagonists in nine other diseases.

In addition, we have discovered, and filed patent applications for, two series of more selective GR-II antagonists that may eventually serve as follow-on compounds to CORLUX. These proprietary compounds bind to the GR-II receptor with a potency similar to that of CORLUX.

Company Information

We were incorporated in the State of Delaware on May 13, 1998. Our trademarks include Corcept^™ and CORLUX. We have applied to register these trademarks with the U.S. Patent and Trademark Office. Other service marks, trademarks and tradenames referred to in this prospectus are the property of their respective owners.

Our principal executive offices are located at 275 Middlefield Road, Suite A, Menlo Park, California 94025, and our telephone number is (650) 327-3270.

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THE OFFERING

The number of shares of our common stock outstanding after this offering is based on 18,142,128 shares outstanding on March 31, 2004 and does not take into account:

Unless otherwise indicated, all information in this prospectus:

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SUMMARY FINANCIAL DATA

(in thousands, except per share data)

The as adjusted balance sheet data above assumes the issuance of 5,000,000 shares of our common stock in this offering at an assumed initial public offering price of $12.00 per share, after deducting underwriting discounts and commissions and estimated offering expenses payable by us, and the automatic conversion of all of the outstanding shares of our convertible preferred stock into 8,807,146 shares of common stock upon the completion of this offering.

See our financial statements and related notes for a description of the calculation of the historical and pro forma net loss per common share and weighted-average number of shares used in computing the historical and pro forma per common share data.

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RISK FACTORS

You should carefully consider the risks described below before making an investment decision. Our business could be harmed by any of these risks. The trading price of our common stock could decline due to any of these risks, and you may lose all or part of your investment. In assessing these risks, you should also refer to the other information contained in this prospectus, including our financial statements and related notes.

Risks Related to Our Business

We have incurred losses since inception and anticipate that we will incur continued losses for the foreseeable future.

We are a development stage company with no current source of product revenue. We have a limited history of operations and have focused primarily on clinical trials, and if the outcome of future clinical trials support it, we plan to seek FDA regulatory clearance to market CORLUX for the treatment of the psychotic features of PMD. Historically, we have funded our operations primarily from the sale of our equity securities. We have incurred losses in each year since our inception in 1998. Our net losses in 2001, 2002 and 2003 were approximately $7.5 million, $18.5 million and $9.8 million, respectively. As of December 31, 2003, we had an accumulated deficit of approximately $37.9 million. We do not know when or if we will generate product revenue. We expect our research and development expenses to increase in connection with the planned pivotal clinical trials and other development activities for other product candidates. We expect to incur significant sales and marketing expenses related to our market research activities for CORLUX and our development of a sales and marketing staff. As a result, we expect that our losses will increase for the foreseeable future. We are unable to predict the extent of any future losses or whether or when we will become profitable.

We depend heavily on the success of our lead product candidate, CORLUX, which is still in development. If we are unable to commercialize CORLUX, or experience significant delays in doing so, we may be unable to generate revenues and our stock price may decline.

We have invested a significant portion of our time and financial resources since our inception in the development of CORLUX. We currently do not have any commercial products and we anticipate that for the foreseeable future our ability to generate revenues and achieve profitability will be solely dependent on the successful development, approval and commercialization of CORLUX. We plan to conduct, in the United States, at least two pivotal clinical trials for CORLUX for the treatment of the psychotic features of PMD before submitting an application for FDA approval. While we expect that these trials will be completed before the end of the first half of 2006, we cannot assure you that this will occur. We may decide, or the FDA may require us, to pursue additional clinical trials or other studies on CORLUX. If we are unable to successfully conclude our clinical development program and obtain regulatory approval for CORLUX for the treatment of the psychotic features of PMD, we may be unable to generate revenue and our stock price may decline.

Many factors could harm our efforts to develop and commercialize CORLUX, including:

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Our clinical trials may not demonstrate that CORLUX is safe and effective. If our clinical trials of CORLUX for the treatment of the psychotic features of PMD do not demonstrate safety and efficacy, or if the clinical trials are delayed or terminated, our business will be harmed.

To gain regulatory approval from the FDA to market CORLUX, our planned pivotal clinical trials must demonstrate the safety and efficacy of CORLUX for the treatment of the psychotic features of PMD. Clinical development is a long, expensive and uncertain process and is subject to delays. Favorable results of preclinical studies and initial clinical trials of CORLUX are not necessarily indicative of the results we will obtain in later clinical trials. While we have obtained favorable results in some of our clinical trials, these results have not been sufficient to support an application for FDA approval. Our future clinical trials may not demonstrate that CORLUX is effective.

In addition, data obtained from pivotal clinical trials are susceptible to varying interpretations, which could delay, limit or prevent regulatory approval. To obtain marketing approval, we may decide, or the FDA or other regulatory authorities may require us, to pursue additional pivotal clinical or other studies. These trials could significantly delay the approval and commercialization of CORLUX and would require us to commit significant additional financial resources. Even after we conduct these additional clinical trials, we may not receive regulatory approval to market CORLUX.

We intend to submit the protocol for our first pivotal clinical trial to the FDA for a special protocol assessment, or SPA, pursuant to which the FDA will assess whether the protocol is adequate to meet the scientific and regulatory requirements necessary to support marketing approval of CORLUX for the treatment of the psychotic features of PMD. In connection with the assessment, we may decide, or the FDA may require us, to modify the protocol by, for example, changing the proposed primary endpoint, the size of the study or otherwise, which may result in a delay in the completion of our clinical trials.

Many other factors could delay or result in termination of our clinical trials, including:

In addition to our pivotal trials, we plan to conduct carcinogenicity studies and toxicology tests in support of our planned NDA to market CORLUX for the treatment of the psychotic features of PMD. We cannot assure you that these studies and tests will produce results that support our planned NDA, or these studies and tests may delay commercialization of CORLUX.

We depend on clinical investigators and clinical sites to enroll patients in our clinical trials and other third parties to manage the trials and to perform related data collection and analysis, and, as a result, we may face costs and delays outside of our control.

We plan to enroll an aggregate of approximately 500 patients in two randomized, double-blind, placebo-controlled trials to further assess the safety and efficacy of CORLUX for the treatment of the psychotic features of PMD. If successful, we expect to use these trials as pivotal clinical trials in support of an NDA to market CORLUX in the United States. We rely on clinical investigators and clinical sites to enroll these patients and other third parties to manage the trial and to perform related data collection and analysis. However, we may not be able to control the amount and timing of resources that the clinical sites that conduct the clinical testing may devote to our pivotal clinical trials. If these clinical

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investigators and clinical sites fail to enroll a sufficient number of patients in our pivotal clinical trials, we will be unable to complete these trials, which could prevent us from obtaining regulatory approvals for CORLUX.

We have contracted with Scirex Corporation and PPD Development, LP, or PPD, to perform investigator supervision, data collection and analysis in our pivotal clinical trials. In addition, we have identified over 30 clinical sites for our pivotal clinical trials and are in the process of qualifying those sites and negotiating contracts with them to conduct clinical testing. We may not be able to maintain these relationships with Scirex and PPD or to establish relationships with qualified clinical sites without undue delays or excessive expenditures. Any delay in contracting with qualified clinical sites to conduct our clinical testing may delay the completion of our pivotal clinical trials or the commercialization of CORLUX.

Our agreements with clinical investigators and clinical sites for clinical testing and with Scirex and PPD for trial management services place substantial responsibilities on these parties, which could result in delays in, or termination of, our pivotal clinical trials if these parties fail to perform as expected. For example, if any of our clinical trial sites fail to comply with FDA-approved good clinical practices, we may be unable to use the data gathered at those sites. If these clinical investigators, clinical sites or other third parties do not carry out their contractual duties or obligations or fail to meet expected deadlines, or if the quality or accuracy of the clinical data they obtain is compromised due to their failure to adhere to our clinical protocols or for other reasons, our pivotal clinical trials may be extended, delayed or terminated, and we may be unable to obtain regulatory approval for, or successfully commercialize, CORLUX.

If we are unable to obtain or maintain regulatory approval, we will be limited in our ability to commercialize our products, including CORLUX, and our business will be harmed.

The research, testing, manufacturing, selling and marketing of product candidates are subject to extensive regulation by the FDA and other regulatory authorities in the United States and other countries, which regulations differ from country to country. Obtaining and maintaining regulatory approval typically is an uncertain process, is costly and takes many years. In addition, failure to comply with the FDA and other applicable foreign and U.S. regulatory requirements may subject us to administrative or judicially imposed sanctions. These include warning letters, civil and criminal penalties, injunctions, product seizure or detention, product recalls, total or partial suspension of production, and refusal to approve pending NDAs, or supplements to approved NDAs.

Regulatory approval of an NDA or NDA supplement is never guaranteed. Despite the time, resources and effort expended, failure can occur at any stage. The FDA has substantial discretion in the drug approval process. The FDA can deny, delay or limit approval of a product candidate for many reasons including:

Future governmental action or changes in FDA policy or personnel may also result in delays or rejection of an NDA in the United States. In addition, because the only currently FDA-approved use of mifepristone is the termination of pregnancy, we expect that the label for CORLUX will include some limitations, including a warning that it should not be used by pregnant women.

If we receive regulatory approval for our product candidates, including CORLUX, we will also be subject to ongoing FDA obligations and continued regulatory oversight and review, such as continued safety reporting requirements; and we may also be subject to additional FDA post-marketing obligations. If we are not able to maintain regulatory compliance, we may not be permitted to market our products.

Any regulatory approvals that we receive for our product candidates may also be subject to limitations on the indicated uses for which the drug may be marketed or contain requirements for potentially costly post-marketing follow-up studies. In addition, if the FDA approves any of our product

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candidates, the labeling, packaging, adverse event reporting, storage, advertising, promotion and record-keeping for the drug will be subject to extensive regulatory requirements. The subsequent discovery of previously unknown problems with the drug, including adverse events of unanticipated severity or frequency, may result in restrictions on the marketing of the drug, and could include withdrawal of the drug from the market.

Failure to obtain regulatory approval in foreign jurisdictions will prevent us from marketing our products abroad.

We intend to market our products in international markets. Outside the United States, we can market a product only if we receive a marketing authorization and, in some cases, pricing approval, from the appropriate regulatory authorities. This foreign regulatory approval process includes all of the risks, and in some cases, additional risks, associated with the FDA approval process. The approval procedure varies among countries and can involve additional testing, and the time required to obtain approval may differ from that required to obtain FDA approval. We have not taken any actions to obtain foreign approvals. We may not obtain foreign regulatory approvals on a timely basis, if at all.

Approval by the FDA does not ensure approval by regulatory authorities in other countries, and approval by one foreign regulatory authority does not ensure approval by regulatory authorities in other foreign countries or by the FDA. We may not be able to file for regulatory approvals and may not receive necessary approvals to commercialize our products in any market.

The “fast track” designation for development of CORLUX for the treatment of the psychotic features of PMD may not lead to a faster development or regulatory review or approval process.

If a drug is intended for the treatment of a serious or life-threatening condition and the drug demonstrates the potential to address unmet medical needs for this condition, the drug sponsor may apply for FDA “fast track” designation for a particular indication. Marketing applications filed by sponsors of products in fast track development may qualify for expedited FDA review under the policies and procedures offered by the FDA, but the fast track designation does not assure any such qualification. Although we have obtained a fast track designation from the FDA for CORLUX for the treatment of the psychotic features of PMD, we may not experience a faster development process, review or approval compared to drugs considered for approval under conventional FDA procedures. In addition, the FDA may withdraw our fast track designation at any time. If we lose our fast track designation, the approval process may be delayed. In addition, our fast track designation does not guarantee that we will qualify for or be able to take advantage of the expedited review procedures and does not increase the likelihood that CORLUX will receive regulatory approval for the treatment of the psychotic features of PMD.

Even if we receive approval for the marketing and sale of CORLUX for the treatment of the psychotic features of PMD, it may never be accepted as a treatment for PMD.

Many factors may affect the market acceptance and commercial success of CORLUX for the treatment of the psychotic features of PMD. Although there is currently no FDA-approved treatment for PMD, there are two treatment approaches currently used by psychiatrists: ECT and combination drug therapy. Even if the FDA approves CORLUX for the treatment of the psychotic features of PMD, physicians may not adopt CORLUX. Physicians will recommend the use of CORLUX only if they determine, based on experience, clinical data, side effect profiles and other factors, that it is preferable to other products or treatments then in use. Acceptance of CORLUX among influential practitioners will be essential for market acceptance of CORLUX.

Other factors that may affect the market acceptance and commercial success of CORLUX for the treatment of the psychotic features of PMD include:

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The failure of CORLUX to achieve market acceptance would prevent us from generating meaningful product revenue.

Public perception of the active ingredient in CORLUX, mifepristone or RU 486, may limit our ability to market and sell CORLUX.

The active ingredient in CORLUX, mifepristone or RU 486, is used to terminate pregnancy. As a result, mifepristone has been and continues to be the subject of considerable ethical and political debate in the United States and elsewhere. Public perception of mifepristone may limit our ability to engage alternative manufacturers and may limit the commercial acceptance of CORLUX by patients and physicians. Additionally, even though appropriate measures will be required to avoid prescribing CORLUX to a pregnant woman, physicians may decline to prescribe CORLUX to a woman simply to avoid altogether any risk of unintentionally terminating a pregnancy.

We have no manufacturing capabilities and we currently depend on third parties who are single source suppliers to manufacture CORLUX. If these suppliers are unable to continue manufacturing CORLUX and we are unable to contract quickly with alternative sources, our business will be harmed.

We currently have no experience in, and we do not own facilities for, manufacturing any products. We have a contract with ScinoPharm Taiwan, Ltd., a manufacturer of the active pharmaceutical ingredient, or API, of mifepristone and a contract with KP Pharmaceutical Technology, Inc., a tablet manufacturer for CORLUX. If we are unable to reach an agreement acceptable to us with a second API manufacturer that we have identified, ScinoPharm will be a single source supplier. Our agreement with ScinoPharm is terminable by either party at any time. The possible second API manufacturer we have identified and ScinoPharm both obtain the raw material they use to manufacture mifepristone from the same single source supplier. KP Pharmaceutical is a single source supplier to us as well. Our agreement with KP Pharmaceutical is effective through February 2005, but may be extended by mutual agreement. We have not yet identified an alternative tablet manufacturer. If we are unable, for whatever reason, to obtain the active pharmaceutical ingredient or CORLUX tablets from our contract manufacturers, we may not be able to manufacture in a timely manner, if at all.

If our third party manufacturers of CORLUX fail to comply with FDA regulations or otherwise fail to meet our requirements, our product development and commercialization efforts may be delayed.

We depend on third party manufacturers to supply the active pharmaceutical ingredient in CORLUX and to manufacture CORLUX tablets. These suppliers and manufacturers must comply with the FDA’s current Good Manufacturing Practices, or cGMP, regulations and guidelines. Our suppliers and manufacturers may encounter difficulties in achieving quality control and quality assurance and may experience shortages of qualified personnel. Their failure to follow cGMP or other regulatory requirements and to document their compliance with cGMP may lead to significant delays in the availability of products for commercial use or clinical study or the termination or hold on a clinical study, or may delay or prevent filing or approval of marketing applications for CORLUX.

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Failure of our third party suppliers and manufacturers or us to comply with applicable regulations could result in sanctions being imposed on us, including fines, injunctions, civil penalties, failure of regulatory authorities to grant marketing approval of our products, delays, suspension or withdrawal of approvals, license revocation, seizures or recalls of products, operating restrictions and criminal prosecutions, any of which could harm our business. If the operations of any current or future supplier or manufacturer were to become unavailable for any reason, commercialization of CORLUX could be delayed and our revenue from product sales could be reduced.

We may use a different third-party manufacturer to produce commercial quantities of CORLUX than we are using in our clinical trials. The FDA requires us to conduct a study to demonstrate that the tablets used in our clinical trials are equivalent to the final commercial product. If we are unable to establish that the tablets are equivalent or if the FDA disagrees with the results of our study, commercial launch of CORLUX would be delayed.

If we or others identify side effects after our products are on the market, we may be required to perform lengthy additional clinical trials, change the labeling of our products or withdraw our products from the market, any of which would hinder or preclude our ability to generate revenues.

If we or others identify side effects after any of our products are on the market:

Any of these events could harm or prevent sales of the affected products or could substantially increase the costs and expenses of commercializing and marketing these products.

If CORLUX or future product candidates conflict with the patents of others or if we become involved in other intellectual property disputes, we could have to engage in costly litigation or obtain a license and we may be unable to commercialize our products.

Our success depends in part on our ability to obtain and maintain adequate patent protection for the use of CORLUX for the treatment of the psychotic features of PMD and other potential uses of GR-II antagonists. If we do not adequately protect our intellectual property, competitors may be able to use our intellectual property and erode our competitive advantage.

To date, we own two U.S. patents and have exclusively licensed three issued U.S. patents, in each case along with a number of corresponding foreign patents or patent applications. We also have nine U.S. method of use patent applications for GR-II antagonists and two composition of matter patent applications covering specific GR-II antagonists. We have applied, and will continue to apply, for patents covering our product candidates as we deem appropriate. Our patent applications and patents licensed or issued to us may be challenged by third parties and our patent applications may not result in issued patents. For example, a third party has alleged that it also has rights to the technology that led to the patent for the use of GR-II antagonists to treat the psychotic features of PMD. The third party is a prior employer of one of our founders, Dr. Alan Schatzberg and it alleges that the invention of the technology underlying this patent was conceived by Dr. Schatzberg and/or another employee of the employer while the two were employed by the third party. We believe that the invention was actually conceived by Drs. Schatzberg and Belanoff while they were employed by Stanford University and that the patent was

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appropriately assigned by them to Stanford University. We believe we will prevail if this matter is pursued against us. If, however, the third party’s claims were successful, it would have rights to market GR-II antagonists to treat the psychotic features of PMD or to license those rights to others and our business could be materially harmed. In addition, Akzo Nobel has filed an observation in our exclusively licensed European patent application with claims directed to PMD, in which Akzo Nobel challenges the claims of that patent application. We plan to vigorously rebut the points raised by Akzo. During prosecution of the U.S. patent for the use of CORLUX to treat the psychotic features of PMD, the U.S. Patent and Trademark Office considered issues similar to those raised by Akzo and the U.S. patent was ultimately granted. We cannot assure you, however, that the European Patent Office will reach the same conclusion. Should Akzo’s arguments persuade the European Patent Office that the claims should not issue, we will not have the benefit of patent protection in Europe for CORLUX to treat the psychotic features of PMD.

We have exclusively licensed three issued U.S. patents and one patent application from Stanford University for the use of GR-II antagonists in the treatment of PMD and early dementia, including early Alzheimer’s disease, and for increasing blood-brain barrier permeability. We bear the costs of protecting and defending the rights to these patents. In order to maintain the exclusive license to these patents until their expiration, we are obligated to make milestone and royalty payments to Stanford University. We are currently in compliance with our obligations under these agreements. If we become noncompliant, we may lose the right to commercialize CORLUX for the treatment of PMD and Alzheimer’s disease and our business would be materially harmed.

Our presently pending and future patent applications may not issue as patents, and any patent issued to us may be challenged, invalidated, held unenforceable or circumvented. For example, the arguments presented by Akzo Nobel could be raised in the United States either before the U.S. Patent and Trademark Office or in a court of law. Furthermore, the claims in patents which have been issued to us, or which may be issued to us in the future, may not be sufficiently broad to prevent third parties from producing competing products. In addition, the laws of various foreign countries in which we compete may not protect our intellectual property to the same extent as do the laws of the United States. If we fail to obtain adequate patent protection for our proprietary technology, our competitors may produce competing products based on our technology, which would substantially impair our ability to compete.

If a third party were successful in asserting an infringement claim against us, we could be forced to pay damages and prevented from developing, manufacturing or marketing our potential products. We do not have liability insurance for patent infringements. A third party could require us to obtain a license to continue to use their intellectual property, and we may not be able to do so on commercially acceptable terms, or at all. We believe that significant litigation will continue in our industry regarding patent and other intellectual property rights. If we become involved in litigation, it could consume a substantial portion of our resources. Regardless of the merit of any particular claim, defending a lawsuit takes significant time, is expensive and diverts management’s attention from other business.

If we are unable to protect our trade secrets and proprietary information, our ability to compete in the market could be diminished.

In addition to patents, we rely on a combination of confidentiality, nondisclosure and other contractual provisions, laws protecting trade secrets and security measures to protect our trade secrets and proprietary information. Nevertheless, these measures may not adequately protect our trade secrets or other proprietary information. If they do not adequately protect our rights, third parties could use our proprietary information, which could diminish our ability to compete in the market. In addition, employees, consultants and others who participate in the development of our products may breach their agreements with us regarding our trade secrets and other proprietary information, and we may not have adequate remedies for the breach. We also realize that our trade secrets may become known through means not currently foreseen. Notwithstanding our efforts to protect our trade secrets and proprietary information, our

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competitors may independently develop similar or alternative products that are equal or superior to our product candidates without infringing on any of our proprietary information or trade secrets.

Our licensed patent covering the use of mifepristone to treat PMD is a method of use patent rather than a composition of matter patent, which increases the risk that physicians will prescribe another manufacturer’s mifepristone for the treatment of PMD rather than CORLUX.

We have an exclusive license from Stanford University to a patent covering the use of GR-II antagonists, including mifepristone, for the treatment of PMD. A method of use patent covers only a specified use of a particular compound, not a particular composition of matter. All of our issued patents and all but one of our 10 U.S. patent applications relate to use patents. Because none of our issued patents covers the composition of mifepristone or any other compound, we cannot prevent others from commercializing mifepristone or any other GR-II antagonist. If others receive approval to manufacture and market mifepristone or any other GR-II antagonist, physicians could prescribe mifepristone or any other GR-II antagonist for PMD patients instead of CORLUX. Although any such “off-label” use would violate our licensed patent, effectively monitoring compliance with our licensed patent may be difficult and costly. In addition, if others develop a treatment for PMD that works through a mechanism which does not involve the GR-II receptor, physicians could prescribe that treatment instead of CORLUX.

If Stanford University were to terminate our CORLUX license due to breach of the license on our part, we would not be able to commercialize CORLUX for the treatment of the psychotic features of PMD.

Our efforts to discover, develop and commercialize new product candidates beyond CORLUX are at a very early stage. If we fail to identify and develop additional uses for GR-II antagonists, we may be unable to market additional products.

To develop additional sources of revenue, we believe that we must identify and develop additional product candidates. We have only recently begun to expand our research and development efforts toward identifying and developing product candidates in addition to CORLUX for the treatment of the psychotic features of PMD. We own or have exclusively licensed issued U.S. patents covering the use of GR-II antagonists to treat PMD, early dementia, mild cognitive impairment, psychosis associated with cocaine addiction and weight gain following treatment with antipsychotic medication, in addition to nine U.S. method of use patent applications covering GR-II antagonists for the treatment of a number of other neurological and psychiatric disorders and two U.S. composition of matter patent applications covering specific GR-II antagonists.

We may not develop product candidates for any of the indications or compounds covered by our patents and patent applications. Typically, there is a high rate of attrition for product candidates in preclinical and clinical trials, so our product development efforts may not lead to commercially viable products. The use of GR-II antagonists may not be effective to treat these conditions or any other indications. In addition, we could discover that the use of GR-II antagonists in these patient populations has unacceptable side effects or is otherwise not safe.

We only have experience with CORLUX and we may determine that CORLUX is not desirable for uses other than for the treatment of the psychotic features of PMD. In that event, we would have to identify and may need to secure rights to a different GR-II antagonist. Our ongoing discovery research program may fail to generate commercially viable product candidates in spite of the resources we are dedicating to the program. Even if product candidates are identified, we may abandon further development efforts before we reach clinical trials or after expending significant expense and time conducting clinical trials. Moreover, governmental authorities may enact new legislation or regulations that could limit or restrict our development efforts. If we are unable to successfully discover and commercialize new uses for GR-II antagonists, we may be unable to generate sufficient revenue to support our operations.

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Failure to raise additional capital or generate the significant capital necessary to expand our operations and invest in new products could reduce our ability to compete.

We anticipate that our existing capital resources and the net proceeds from this offering will enable us to maintain currently planned operations through at least the next two years. However, our expectations are based on our current operating plan, which may change as a result of many factors, including:

Consequently, we may need additional funding sooner than anticipated. We currently have no credit facility or committed sources of capital. Our inability to raise capital would harm our business and product development efforts.

In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in dilution to our then-existing stockholders.

We may have substantial exposure to product liability claims and may not have adequate insurance to cover those claims.

We may be subject to product liability or other claims based on allegations that the use of our products has resulted in adverse effects or that our products are not effective, whether by participants in our clinical trials or by patients using our products. A product liability claim may damage our reputation by raising questions about our products’ safety or efficacy and could limit our ability to sell a product by preventing or interfering with product commercialization. In addition, the active ingredient in CORLUX is used to terminate pregnancy. Therefore, necessary and strict precautions must be taken by clinicians using the drug in our clinical trials and, if approved by the FDA, physicians prescribing the drug to women with childbearing potential. The failure to observe these precautions could result in significant product claims.

We have only limited product liability insurance coverage, with limits customary for a development stage company. We intend to expand our product liability insurance coverage to any products for which we obtain marketing approval. However, this insurance may be prohibitively expensive or may not fully cover our potential liabilities. Our inability to obtain adequate insurance coverage at an acceptable cost could prevent or inhibit the commercialization of our products. Defending a lawsuit could be costly and significantly divert management’s attention from conducting our business. If a third party successfully sues us for any injury caused by our products, our liability could exceed our total assets.

We have no sales and marketing staff and will need to develop sales and marketing capabilities to successfully commercialize CORLUX and any future uses of GR-II antagonists.

Our employees have limited experience in marketing or selling pharmaceutical products and we currently have no sales and marketing staff. To achieve commercial success for any approved product, we must either develop a sales and marketing force or enter into arrangements with others to market

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and sell our products. We currently plan to establish a small, specialty sales force to market and sell CORLUX in the United States for the treatment of the psychotic features of PMD. However, our sales and marketing efforts may not be successful or cost-effective. In the event that the commercial launch of CORLUX is delayed due to FDA requirements or other reasons, we may establish a sales and marketing force too early relative to the launch of CORLUX. This may be expensive, and our investment would be lost if the sales and marketing force could not be retained. If our efforts to develop a sales and marketing force are not successful, cost-effective and timely, we may not achieve profitability.

We will need to substantially increase the size of our organization, and we may experience difficulties in managing growth.

As we expand our research and development efforts and develop a sales and marketing organization, we expect to experience substantial growth, which may strain our operations, product development and other managerial and operating resources. Future growth will impose significant added responsibilities on members of management, including the need to identify, recruit, maintain and integrate additional employees. To date, we have relied on a small management team, including a number of part-time contributors. Our future financial performance and our ability to compete effectively will depend, in part, on our ability to manage any future growth effectively. To that end, we must be able to:

We may not be able to accomplish these tasks, and our failure to accomplish any of them could harm our business.

If we are unable to obtain acceptable prices or adequate reimbursement for our products from third-party payors, we will be unable to generate significant revenues.

There is significant uncertainty related to the availability of insurance coverage and reimbursement for newly approved drugs. The commercial success of our drugs in both domestic and international markets is substantially dependent on whether third-party coverage and reimbursement is available for the ordering of our drugs by the medical profession for use by their patients. Medicare, Medicaid, health maintenance organizations and other third-party payors are increasingly attempting to contain healthcare costs by limiting both coverage and the level of reimbursement of new drugs, and, as a result, they may not cover or provide adequate payment for our drugs. The continuing efforts of government and third-party payors to contain or reduce the costs of health care may limit our revenues. Our dependence on the commercial success of CORLUX alone makes us particularly susceptible to any cost containment or reduction efforts. Accordingly, even if CORLUX or future product candidates are approved for commercial sale, unless government and other third-party payors provide adequate coverage and reimbursement for our products, physicians may not prescribe them. We intend to sell CORLUX directly to hospitals if we receive FDA approval. As a result, we will need to obtain approval from hospital formularies to receive wide-spread third-party reimbursement. If we fail to obtain that approval, we will be unable to generate significant revenues.

In some foreign markets, pricing and profitability of prescription pharmaceuticals are subject to government control. In the United States, we expect that there will continue to be federal and state proposals for similar controls. Also, the trends toward managed health care in the United States and proposed legislation intended to reduce the cost of government insurance programs could significantly

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influence the purchase of health care services and products and may result in lower prices for our products or the exclusion of our products from reimbursement programs.

We face competition from companies with substantial financial, technical and marketing resources, which could limit our future revenues from the commercialization of CORLUX for the treatment of the psychotic features of PMD.

If approved for commercial use, CORLUX as a treatment for PMD will compete with established treatments, including ECT and combination drug therapy.

Combination drug therapy consists of the use of antipsychotic and antidepressant drugs, not currently approved for the treatment of PMD. The antipsychotics are prescribed for off-label use by physicians to treat the psychotic features of PMD, which is the clinical target of CORLUX. Antipsychotics include Bristol-Myers Squibb’s Abilify, Novartis’ Clozaril, Pfizer’s Geodon and Navane, Ortho-McNeil’s Haldol, Janssen Pharmaceutica’s Risperdal, AstraZeneca’s Seroquel, GlaxoSmithKline’s Stelazine and Thorazine, Mylan’s thioridazine, Schering Corporation’s Trilafon and Eli Lilly’s Zyprexa. CORLUX may not compete effectively with these established treatments. While we are unaware of any other ongoing clinical trials for new drugs for the treatment of PMD, other companies may also be developing new drug products to treat PMD. Our present and potential competitors include major pharmaceutical companies, as well as specialized pharmaceutical firms, universities and public and private research institutions. Moreover, we expect competition to intensify as technical advances are made. These competitors, either alone or with collaborative parties, may succeed with the development and commercialization of drug products that are superior to and more cost-effective than CORLUX. Many of our competitors and related private and public research and academic institutions have substantially greater experience, more financial resources and larger research and development staffs than we do. In addition, many of these competitors, either alone or together with their collaborative partners, have significantly greater experience than we do in developing drugs, obtaining regulatory approvals, manufacturing and commercializing products.

Accordingly, CORLUX may not be an effective competitor against established treatments and our present or potential competitors may succeed in developing drug products that are superior to CORLUX or render CORLUX obsolete or non-competitive. If we are unable to establish CORLUX as a superior and cost-effective treatment for PMD, or any future use, we may be unable to generate the revenues necessary to support our business.

Rapid technological change could make our products obsolete.

Pharmaceutical technologies have undergone rapid and significant change and we expect that they will continue to do so. Any products and processes that we develop may become obsolete or uneconomical before we recover any or all expenses incurred in connection with their development. Rapid technological change could make our products obsolete or uneconomical.

If we lose our key personnel or are unable to attract and retain additional skilled personnel, we may be unable to pursue our product development and commercialization efforts.

We depend substantially on the principal members of our management and scientific staff, including Joseph K. Belanoff, M.D., our Chief Executive Officer, and Robert L. Roe, M.D., our President. We do not have agreements with any of our executive officers that provide for their continued employment with us or employment insurance covering any of our key personnel. Any officer or employee can terminate his or her relationship with us at any time and work for one of our competitors. The loss of these key individuals could result in competitive harm because we could experience delays in our product research, development and commercialization efforts without their expertise.

Our ability to operate successfully and manage our potential future growth depends significantly upon retaining key research, technical, sales, marketing, managerial and financial personnel, and

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attracting and retaining additional highly qualified personnel in these areas. We face intense competition for such personnel from numerous companies, as well as universities and nonprofit research organizations in the highly competitive northern California business area. Although we believe that we have been successful in attracting and retaining qualified personnel to date, we may not be able to attract and retain sufficient qualified personnel in the future. The inability to attract and retain these personnel could result in delays in the research, development and commercialization of our potential products.

If we acquire other GR-II antagonists, we will incur a variety of costs and may never realize the anticipated benefits of the acquisition.

If appropriate opportunities become available, we may attempt to acquire other GR-II antagonists, particularly GR-II antagonists that do not terminate pregnancy. We currently have no commitments, agreements or plans for any acquisitions. The process of acquiring rights to another GR-II antagonist may result in unforeseen difficulties and expenditures and may absorb significant management attention that would otherwise be available for ongoing development of our business. In addition, we may fail to realize the anticipated benefits of any acquired GR-II antagonist. Future acquisitions could dilute your ownership interest in us and could cause us to incur debt, expose us to future liabilities and result in amortization or other expenses related to goodwill and other intangible assets.

The occurrence of a catastrophic disaster or other similar events could cause damage to our or our manufacturers’ facilities and equipment, which could require us to cease or curtail operations.

Because our executive offices are located in the San Francisco Bay Area and our current manufacturers are located in earthquake-prone areas, our business is vulnerable to damage from various types of disasters or other similarly disruptive events, including earthquake, fire, flood, power loss and communications failures. In addition, political considerations relating to mifepristone may put us and our manufacturers at increased risk for terrorist attacks, protests or other disruptive events. If any disaster or other similar event were to occur, we may not be able to operate our business and our manufacturers may not be able to produce our products. Our insurance may not be adequate to cover, and our insurance policies may exclude coverage for, our losses resulting from disasters or other business interruptions.

Risks Related to this Offering

The market price of our common stock may experience extreme price and volume fluctuations.

Prior to this offering, there has been no public market for our common stock. An active trading market for our common stock may not develop or be sustained following this offering. We have determined the initial public offering price with the representatives of the underwriters based on several factors. This price may vary after this offering. Our stock price is likely to be volatile. The stock market in general and securities of pharmaceutical companies in particular have been highly volatile and may continue to be highly volatile in the future. The following factors, in addition to other risk factors described in this section and general market and economic conditions, may have a significant impact on the market price of our common stock:

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Significant volatility may lead to securities class action litigation against us. Whether or not meritorious, litigation brought against us could result in substantial costs and a diversion of management’s attention and resources. Our insurance to cover claims of this sort may not be adequate.

Securities analysts may not initiate coverage of our common stock or may issue negative reports, and this may have a negative impact on our common stock’s market price.

Securities analysts may elect not to provide research coverage of our common stock after the completion of this offering. If securities analysts do not cover our common stock after the completion of this offering, the lack of research coverage may adversely affect our common stock’s market price. The trading market for our common stock may be affected in part on the research and reports that industry or financial analysts publish about us or our business. If one or more of the analysts who elects to cover us downgrades our stock, our stock price would likely decline rapidly. If one or more of these analysts ceases coverage of our company, we could lose visibility in the market, which in turn could cause our stock price to decline. In addition, recently-adopted rules mandated by the Sarbanes-Oxley Act of 2002, and a global settlement reached in 2003 between the SEC, other regulatory analysts and a number of investment banks will lead to a number of fundamental changes in how analysts are reviewed and compensated. In particular, many investment banking firms will be required to contract with independent financial analysts for their stock research. It may be difficult for companies such as ours with smaller market capitalizations to attract independent financial analysts that will cover our common stock. This could have a negative effect on our market price.

A sale of a substantial number of shares of our common stock may cause the price of our common stock to decline.

Sales of a substantial number of shares of our common stock in the public market following this offering could harm the market price of our common stock. As additional shares of our common stock become available for resale in the public market, the supply of our common stock will increase, which could decrease the price. Subject to applicable volume and other resale restrictions, there will be approximately 18,142,128 million additional shares of common stock eligible for sale beginning 180 days after the effective date of this prospectus upon the expiration of lock-up arrangements between our stockholders and the underwriters.

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Our officers, directors and principal stockholders will control 71% of our common stock after this offering and will be able to significantly influence corporate actions.

After this offering, our officers, directors and principal stockholders will control approximately 71% of our common stock. As a result, these stockholders, acting together, will be able to significantly influence all matters requiring approval by our stockholders, including the election of directors and the approval of mergers or other business combination transactions. The interests of this group of stockholders may not always coincide with our interests or the interests of other stockholders and may prevent or delay a change in control. This concentration of ownership may have the effect of delaying or preventing a change in control and might adversely affect the market price of our common stock. In addition, this significant concentration of share ownership may adversely affect the trading price of our common stock because investors often perceive disadvantages to owning stock in companies with controlling stockholders.

We may incur increased costs as a result of recently enacted and proposed changes in laws and regulations.

Recently enacted and proposed changes in the laws and regulations affecting public companies, including the provisions of the Sarbanes-Oxley Act of 2002 and regulations of the SEC and the Nasdaq Stock Market, will result in increased costs to us. The new rules could make it more difficult or costly for us to obtain certain types of insurance, including director and officer liability insurance, and we may be forced to accept reduced policy limits and coverage or incur substantially higher costs to obtain the same or similar coverage. The impact of these events could also make it more difficult for us to attract and retain qualified persons to serve on our board of directors, or our board committees, or as executive officers. At present, we cannot predict or estimate the amount of the additional costs related to these new rules and regulations or the timing of such costs.

Changes in or interpretations of accounting rules and regulations, such as expensing of stock options, could result in unfavorable accounting charges or require us to change our compensation policies.

Accounting methods and policies for business and marketing practices of pharmaceutical companies, including policies regarding expensing employee stock options, are subject to further review, interpretation and guidance from relevant accounting authorities, including the SEC. For example, we currently are not required to record stock-based compensation charges if an employee’s stock option exercise price equals or exceeds the fair value of our common stock at the date of grant. The Financial Accounting Standards Board has announced its support for recording expense for the fair value of stock options granted. If we were to change our accounting policy to record expense for the fair value of stock options granted and retroactively restate all prior periods presented, then our operating expenses could increase. We rely heavily on stock options to compensate existing employees and attract new employees. If we are required to expense stock options, we may then choose to reduce our reliance on stock options as a compensation tool. If we reduce our use of stock options, it may be more difficult for us to attract and retain qualified employees. If we did not reduce our reliance on stock options, our reported losses would increase. Although we believe that our accounting practices are consistent with current accounting pronouncements, changes to or interpretations of accounting methods or policies in the future may require us to reclassify, restate or otherwise change or revise our financial statements.

Anti-takeover provisions in our charter and bylaws and under Delaware law may make an acquisition of us or a change in our management more difficult, even if an acquisition or a management change would be beneficial to our stockholders.

Provisions in our charter and bylaws as in effect immediately after this offering may delay or prevent an acquisition of us or a change in our management. Some of these provisions divide our board into three classes with only a portion of our directors subject to election at each annual meeting, allow

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us to issue preferred stock without any vote or further action by the stockholders, require advance notification of stockholder proposals and nominations of candidates for election as directors and prohibit stockholders from acting by written consent. In addition, a supermajority vote of stockholders is required to amend our bylaws. Our bylaws provide that special meetings of the stockholders may be called only by our Chairman, President or the board of directors and that the authorized number of directors may be changed only by resolution of the board of directors. These provisions may prevent or delay a change in our board of directors or our management, which is appointed by our board of directors. In addition, because we are incorporated in Delaware, we are governed by the provisions of Section 203 of the Delaware General Corporation Law. Section 203 may prohibit large stockholders, in particular those owning 15% or more of our outstanding voting stock, from merging or combining with us. These provisions in our charter, bylaws and under Delaware law could reduce the price that investors might be willing to pay for shares of our common stock in the future and result in the market price being lower than it would be without these provisions.

We may spend a substantial portion of the net proceeds of this offering in ways that do not yield a favorable return.

We have broad discretion to spend the net proceeds from this offering. As a result, investors in this offering will be relying upon our judgment with only limited information about our specific intentions regarding the use of proceeds. We cannot assure you that the proceeds will be applied in a manner that yields a favorable return.

New investors will experience immediate and substantial dilution in the value of their common stock following this offering.

The assumed initial public offering price is substantially higher than the book value per share of our common stock. Investors purchasing common stock in this offering will, therefore, incur immediate dilution of $9.19 in net tangible book value per share of common stock, based on an assumed initial public offering price of $12.00 per share. Investors will incur additional dilution upon the exercise of outstanding stock options. As a result of this dilution, investors purchasing stock in this offering may receive significantly less than the full purchase price that they paid for the shares purchased in this offering in the event of a liquidation.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus contains forward-looking statements. The forward-looking statements are contained principally in the sections entitled “Summary,” “Risk Factors,” “Use of Proceeds,” “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Business.” These statements involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by the forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

In some cases, you can identify forward-looking statements by terms such as “anticipates,” “believes,” “could,” “estimates,” “expects,” “may,” “plans,” “potential,” “predicts,” “projects,” “should,” “will,” “would,” and similar expressions intended to identify forward-looking statements. Forward-looking statements reflect our current views with respect to future events and are based on assumptions and subject to risks and uncertainties. We discuss many of these risks in this prospectus in greater detail under the heading “Risk Factors.” Given these uncertainties, you should not place undue reliance on these forward-looking statements. Also, forward-looking statements represent our estimates and assumptions only as of the date of this prospectus. You should read this prospectus and the documents that we reference in this prospectus and have filed as exhibits to the registration statement, of which this prospectus is a part, completely and with the understanding that our actual future results may be materially different from what we expect.

Except as required by law, we assume no obligation to update such forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in such forward-looking statements, even if new information becomes available in the future.

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USE OF PROCEEDS

We estimate that the net proceeds from the sale of 5,000,000 shares of common stock that we are selling in this offering will be approximately $54.7 million, based on an assumed initial public offering price of $12.00 per share, after deducting the underwriting discounts and commissions and estimated offering expenses payable by us. If the underwriters’ over-allotment option is exercised in full and none of these shares are sold by the selling stockholder, we estimate that we will receive net proceeds of approximately $63.1 million. We will not receive any proceeds from the sale of common stock by the selling stockholder.

We intend to use the net proceeds of this offering to fund our operations, including approximately $34.5 million for clinical trials, preclinical testing, manufacturing and other research and development activities, and approximately $9.0 million for general and administrative expenses, and the remainder for working capital and other general corporate purposes.

The amounts actually expended for these purposes may vary significantly and will depend on a number of factors, including the amount of our future revenues, expenses and the other factors described under “Risk Factors.” While we have no present understandings, commitments or agreements to enter into any potential acquisitions, we may also use a portion of the proceeds for the acquisition of, or investment in, technologies or products that complement our business. In addition, we will retain broad discretion in the allocation of the net proceeds of this offering. Pending these uses, we intend to invest the net proceeds from this offering in interest-bearing, investment-grade securities.

DIVIDEND POLICY

Since our incorporation, we have not declared or paid any cash dividends on our common stock and do not expect to do so in the foreseeable future. We currently intend to retain all available funds for use in the operation and expansion of our business.

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CAPITALIZATION

The following table sets forth our cash, cash equivalents, and short-term investments, and capitalization as of December 31, 2003 on an actual and pro forma as adjusted basis. This table does not include:

This table should be read in conjunction with “Management’s Discussion and Analysis of Financial Condition and Results of Operation” and the financial statements and related notes included elsewhere in this prospectus.

The pro forma as adjusted information gives effect to the sale in this offering of 5,000,000 shares of common stock at an assumed initial public offering price of $12.00 per share, less underwriting discounts and commissions and estimated offering expenses payable by us. The pro forma as adjusted information also assumes the conversion of all outstanding shares of preferred stock into 8,807,146 shares of common stock upon the completion of this offering.

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DILUTION

The actual net tangible book value as of December 31, 2003 was $(31.5) million, or $(3.37) per share, based on 9,334,982 shares of common stock outstanding. Actual net tangible book value per share represents our total tangible assets less total liabilities and convertible preferred stock by the actual number of outstanding shares of our common stock.

The pro forma net tangible book value of our common stock as of December 31, 2003 was $10.2 million, or approximately $0.56 per share, based on 18,142,128 shares of common stock outstanding pro forma. Pro forma net tangible book value per share represents our total tangible assets less our total liabilities divided by the number of shares of our common stock outstanding after giving effect to the conversion of all outstanding shares of our convertible preferred stock into common stock upon the completion of this offering.

After giving effect to the sale by us of 5,000,000 shares of our common stock in this offering at an assumed initial public offering price of $12.00 per share, less the underwriting discounts and commissions and estimated offering expenses payable by us, our pro forma as adjusted net tangible book value as of December 31, 2003 would have been $64.9 million, or approximately $2.81 per share. This represents an immediate increase in pro forma net tangible book value of $2.25 per share to existing stockholders and an immediate dilution of $9.19 per share to new investors purchasing our common stock in this offering.

The following table illustrates the per share dilution to new investors:

The following table summarizes, on a pro forma as adjusted basis as of December 31, 2003, the differences between the number of shares of common stock purchased from us, the total price and the average price per share paid by existing stockholders and by the new investors, before deducting the underwriting discounts and commissions and estimated offering expenses payable by us, at an assumed initial public offering price of $12.00 per share.

If the underwriters’ over-allotment option is exercised in full and none of these shares are sold by the selling stockholder, the number of shares held by the new investors will be increased to 5,750,000, or approximately 24% of the total numbers of shares of our common stock outstanding after this offering.

The existing stockholder amounts in the table above have been calculated on a pro forma basis, which includes shares outstanding as of December 31, 2003, including the conversion of all outstanding shares of preferred stock into 8,807,146 of common stock upon the completion of this offering, but excludes:

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After this offering and assuming the exercise in full of all options outstanding, vested and exercisable as of December 31, 2003, our pro forma net tangible book value per share as of December 31, 2003 would be $2.81 per share, representing an immediate increase in net tangible book value of $2.24 per share to existing stockholders and an immediate dilution in net tangible book value of $9.19 per share to new investors.

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SELECTED FINANCIAL DATA

(in thousands, except per share data)

The selected financial data set forth below are derived from our financial statements. The statements of operations data for the years ended December 31, 2001, 2002, and 2003 and for the period from inception (May 13, 1998) to December 31, 2003 and the balance sheet data as of December 31, 2002 and 2003 are derived from our audited financial statements included in this prospectus. The statements of operations data for the years ended December 31, 1999 and 2000, and the balance sheet data as of December 31, 1999, 2000 and 2001 have been derived from our audited financial statements which are not included in this prospectus. The selected financial data set forth below should be read in conjunction with our financial statements, the related notes and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included elsewhere in this prospectus.

See our financial statements and related notes for a description of the calculation of the historical and pro forma net loss per common share and the weighted-average number of shares used in computing the historical and pro forma per common share data.

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MANAGEMENT’S DISCUSSION AND ANALYSIS OF

FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion should be read in conjunction with our financial statements and related notes appearing elsewhere in this prospectus. This discussion may contain forward-looking statements based upon current expectations that involve risks and uncertainties. Our actual results and the timing of selected events could differ materially from those anticipated in these forward-looking statements as a result of selected factors, including those set forth under “Risk Factors” and elsewhere in this prospectus. We believe that the section entitled “Risk Factors” includes all material risks that could harm our business.

Overview

We are a pharmaceutical company engaged in the development of drugs for the treatment of severe psychiatric and neurological diseases. Since our inception in May 1998, our activities have primarily been associated with the development of our lead product, CORLUX^™, for the treatment of the psychotic features of PMD under an exclusive patent license from Stanford University. We have been granted “fast track” status by the FDA with respect to CORLUX for the treatment of the psychotic features of PMD. We have completed the analysis of our first two large, double-blind trials, and plan to initiate additional clinical trials in 2004, including two pivotal clinical trials in the United States to support our NDA. We also initiated a clinical study in 2003 to explore the tolerability and efficacy of CORLUX in improving cognition in patients with mild to moderate Alzheimer’s disease. Specifically, our activities have included:

Historically, we have financed our operations and internal growth primarily through private placements of our preferred stock rather than through collaborative or partnership agreements. Therefore, we have no research funding or collaborative payments payable to us and the funding we received from one research institution is repayable to that organization subject to the terms of our convertible note.

We are in the development stage and have incurred significant losses since our inception because we have not generated any revenue, and do not expect to generate any revenue for the foreseeable future. As of December 31, 2003 we had a deficit accumulated during the development stage of approximately $37.9 million. Our historical operating losses have resulted principally from our research and development activities, including clinical trial activities for CORLUX, drug discovery research, non-clinical activities such as toxicology and carcinogenicity studies, manufacturing process development and regulatory activities, as well as general and administrative expenses. We expect to continue to incur net losses over the next several years as we complete our CORLUX clinical trials, apply for regulatory approvals, expand development of GR-II antagonists for new indications, acquire and develop treatments in other therapeutic areas, establish sales and marketing capabilities and expand our operations.

Our business is subject to significant risks, including the risks inherent in our research and development efforts, the results of our CORLUX clinical trials, uncertainties associated with obtaining and enforcing patents, our investment in manufacturing set-up, the lengthy and expensive regulatory approval process and competition from other products. Our ability to successfully generate revenues in the foreseeable future is dependent upon our ability, alone or with others, to develop, obtain regulatory approval for, manufacture and market our lead product.

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Results of Operations

Years Ended December 31, 2003 and 2002

Research and development expenses.    Research and development expenses include the personnel costs related to our development activities including non-cash stock-based compensation, as well as the costs of clinical trial preparations, enrollment and monitoring expenses, regulatory costs and the costs of manufacturing development.

Research and development expenses decreased 39% to $8.1 million for the year ended December 31, 2003, from $13.2 million for the year ended December 31, 2002. This decrease of $5.1 million was primarily attributable to decreases in preclinical and clinical trial expenses of $4.3 million due to the completion of one double-blind PMD clinical trial at the end of 2002 partially offset by the costs of the early-stage Alzheimer’s disease trial commenced in 2003. The decrease was also attributable to a decrease in non-cash stock-based compensation of $1.4 million due to the graded-vesting method used to determine non-cash employee stock-based compensation, which results in greater expense in earlier years. We also experienced decreased costs of $1.3 million related to clinical supplies, as no purchases of clinical supplies were required in 2003, and to certain manufacturing capacity development projects that were completed in 2002. Those decreases were partially offset by an increase in GR-II antagonists drug discovery research activities in 2003 resulting in additional research and development expenses of $1.9 million.

Below is a summary of our research and development expenses by major project:

We expect that research and development expenditures will increase substantially during 2004 and subsequent years due to the continuation and expansion of clinical trials of CORLUX for PMD and early-stage Alzheimer’s disease, the initiation of trials of CORLUX for other indications and additional study expenditures for new GR-II antagonists and other pharmaceutical candidates.

Many factors can affect the cost and timing of our trials including inconclusive results requiring additional clinical trials, slow patient enrollment, adverse side effects among patients, insufficient supplies for our clinical trials and real or perceived lack of effectiveness or safety of our trials. In addition, the development of all of our products will be subject to extensive governmental regulation. These factors make it difficult for us to predict the timing and costs of the further development and approval of our products.

General and administrative expenses.    General and administrative expenses consist primarily of the costs of administrative personnel and related facility costs along with legal, accounting and other professional fees.

General and administrative expenses decreased 67% to $1.9 million for the year ended December 31, 2003, from $5.7 million for the year ended December 31, 2002. This decrease of $3.8 million was primarily attributable to a decrease in non-cash stock-based compensation of $2.5 million. Included in the total decrease is the reversal of $1.4 million expense to reverse stock-based compensation expense as a result of using the graded vesting method for unvested options forfeited by terminated employees and by a director due to a reduction in service. In addition, there was a reduction of $1.2 million in professional service fees, $1.0 million of which related to the expenses of a proposed public offering withdrawn in October 2002. We expect that general and administrative expenditures will

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increase during 2004 and subsequent years due to increasing payroll and non-cash stock-based compensation, commercialization efforts, business development costs associated with growth in our market research, and expanded operational infrastructure. An increase in general and administrative expenses is also expected to accompany our infrastructure growth associated with our public company reporting activities.

Interest and other income, net.    Interest and other income, net, decreased to $203,000 for the year ended December 31, 2003 from $320,000 for the year ended December 31, 2002. The decrease was principally attributable to lower average cash, cash equivalents, and short-term investments balances during the year ended December 31, 2003 as compared to the year ended December 31, 2002.

Interest Expense.    Interest expense of $21,000 for the years ended December 31, 2003 and 2002 represents interest on our convertible note payable to the Institute for the Study of Aging.

Years Ended December 31, 2002 and 2001

Research and development expenses.    Research and development expenses increased 144% to $13.2 million for the year ended December 31, 2002, from $5.4 million for the year ended December 31, 2001. This increase of $7.8 million was primarily attributable to preclinical and clinical trial expenses increasing by $5.5 million as two double-blind PMD clinical trials were in progress throughout 2002. The increase was also attributable to increased costs of $946,000 due to purchases of clinical supplies that were required in 2002 and certain manufacturing capacity development projects that were initiated in 2002. The increase was also attributable to increases in non-cash stock-based compensation expense of $740,000 primarily due to the issuance of common stock options in late 2001 deemed to be below the fair value of common stock.

Below is a summary of our research and development expenses by major project:

General and administrative expenses.    General and administrative expenses increased 116% to $5.7 million for the year ended December 31, 2002, from $2.6 million for the year ended December 31, 2001. This increase of $3.0 million was primarily attributable to a non-cash stock-based compensation expense increase of $1.5 million from the issuance of common stock options in late 2001 deemed to be below the fair value of common stock. The increase was also attributable to a $1.0 million increase in professional service fees primarily related to the expenses of a proposed public offering withdrawn in October 2002 and increased staffing costs of $553,000 due to the expansion of administrative activities to support our research and development. We also experienced an increase in general and administrative activities of $289,000 primarily due to the increased filings of patent applications and prosecution fees in 2002.

Interest and other income, net.    Interest and other income, net, decreased to $320,000 for the year ended December 31, 2002 from $600,000 for the year ended December 31, 2001. The decrease was primarily attributable to lower average cash, cash equivalents and short-term investments balances during the year ended December 31, 2002 as compared to the year ended December 31, 2001.

Interest expense.    Interest expense of $21,000 for the year ended December 31, 2002 represents interest on our convertible note payable to the Institute for the Study of Aging. Interest expense of $48,000 for the year ended December 31, 2001 represents interest on convertible promissory notes

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previously issued to investors and converted to preferred stock in May 2001, as well as interest on the convertible note payable to the Institute for the Study of Aging.

Liquidity and Capital Resources

We have incurred annual operating losses since inception, and at December 31, 2003, we had a deficit accumulated during the development stage of $37.9 million. Since our inception, we have relied primarily on the proceeds from private placements of our equity securities to fund our operations.

At December 31, 2003, we had cash, cash equivalents and short-term investments balances of $11.6 million, compared to $21.5 million at December 31, 2002 and cash and cash equivalents of $23.0 million at December 31, 2001. Net cash used in operating activities for the years ended December 31, 2003, 2002 and 2001, was $10.0 million, $13.2 million and $5.4 million, respectively. The use of cash in each period was primarily a result of net losses associated with our research and development activities and amounts incurred to develop our administrative infrastructure. If this offering is significantly delayed or we do not complete it, we may need to curtail or delay our planned clinical trials and other product development activities.

We believe that the net proceeds from this offering, together with our current cash balances and interest thereon, will be sufficient to complete our ongoing and planned clinical trials reflected in the description of business, to conduct appropriate development studies and to satisfy our other anticipated cash needs for operating expenses for at least the next two years. However, we cannot be certain that additional funding will not be required and, if required, will be available on acceptable terms, or at all. Further any additional equity financing may be dilutive to stockholders, and debt financing, if available, may involve restrictive covenants. If adequate funds are not available, we may be required to delay, reduce the scope of or eliminate one or more of our research or development programs or to obtain funds through collaborations with others that are on unfavorable terms or that may require us to relinquish rights to certain of our technologies or products, including potentially our lead product, that we would otherwise seek to develop on our own.

Contractual Obligations and Commercial Commitments

Our contractual payment obligations that are fixed and determinable as of December 31, 2003 were as follows:

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We also have other contractual payment obligations, the timing of which are contingent on future events. Under our license agreement with Stanford University related to the patent covering the use of GR-II antagonists to treat the psychosis associated with PMD and early dementia, including early Alzheimer’s disease, we are obligated to make milestone payments to Stanford of $50,000 upon filing of an NDA covering the licensed product and $200,000 upon FDA approval of the licensed product. Under our license agreement with Stanford related to the patent application covering the use of GR-II antagonists for modulation of the blood-brain barrier, we are obligated to make milestone payments to Stanford of $100,000 upon commencement of pivotal clinical trials related to the licensed product and $250,000 upon FDA approval of the licensed product. The milestone payments payable to Stanford under these licenses are creditable against future royalties. In addition, our agreement with ScinoPharm Taiwan that provides for the manufacture and supply of the active pharmaceutical ingredient for CORLUX includes a minimum purchase commitment of $1,000,000 per year following the commercial launch of CORLUX.

We enter into agreements with third-party service providers to conduct our clinical and preclinical trials and make payments to these providers based upon the number of patients enrolled in the trial as well as the completion of certain agreed-upon milestones. We are currently unable to estimate the amounts to be paid or the time period in which amounts will be paid pursuant to these agreements.

Net Operating Loss Carryforwards