As filed with the Securities and Exchange Commission on February 2, 2005

Registration No. 333-114299

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C 20549

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

FAVRILLE, INC.
(Exact name of registrant as specified in its charter)

John P. Longenecker, Ph.D.
President and Chief Executive Officer
Favrille, Inc.
10421 Pacific Center Court, Suite 150
San Diego, CA 92121
(858) 526-8000
(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 after the effective date 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, check the following box.    o

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

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

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

If delivery of the Prospectus is expected to be made pursuant to Rule 434, check the following box. o

CALCULATION OF REGISTRATION FEE

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Includes 900,000 shares that the underwriters have the option to purchase to cover over-allotments.

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Estimated solely for the purpose of calculating the amount of the registration fee in accordance with Rule 457(o) under the Securities Act of 1933, as amended.

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Previously paid.

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 that specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

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

Subject to completion, dated February 2, 2005

Prospectus

6,000,000 shares

Common Stock

        This is the initial public offering of Favrille, Inc. No public market currently exists for our common stock.

We currently anticipate the initial public offering price of our common stock to be between $7.00 and $8.00 per share. We applied to have our common stock listed on the Nasdaq National Market under the symbol "FVRL."

Investing in our common stock involves a high degree of risk. See "Risk Factors" beginning on page 7.

        We have granted the underwriters a 30-day option to purchase up to 900,000 additional shares to cover any over-allotments.

Delivery of shares will be made on or about                         , 2005.

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.

The date of this prospectus is                       , 2005.

TABLE OF CONTENTS

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.

PROSPECTUS SUMMARY

This summary highlights information about our business and this offering contained elsewhere in this prospectus. This summary does not contain all of the information you should consider before investing in our common stock. Before deciding to invest in our common stock, you should read this entire prospectus carefully, including the section entitled "Risk Factors" and our financial statements and accompanying notes included elsewhere in this prospectus.

Our Business

We are a biopharmaceutical company focused on the research, development and commercialization of targeted immunotherapies for the treatment of cancer and diseases of the immune system. We have developed a proprietary technology that enables us to manufacture active immunotherapy product candidates that are designed to stimulate a patient's immune system to mount a specific and sustained response to disease.

Our lead product candidate, FavId, is an active immunotherapy for the treatment of indolent B-cell non-Hodgkin's lymphoma, or NHL, that is based upon unique genetic information extracted from a patient's tumor. FavId is being developed to be used following treatment with existing standards of care to induce more durable remissions for patients with indolent B-cell NHL. In May 2004, we received a Special Protocol Assessment, or SPA, from the FDA for our randomized, double-blind, placebo-controlled Phase 3 clinical trial evaluating FavId, which we initiated in July 2004. To date, FavId has been evaluated in two multi-center, open-label Phase 2 clinical trials involving over 120 patients. Preliminary results from these trials suggest that FavId can induce remissions when used alone and may increase time to disease progression, or TTP, following treatment with the approved product Rituxan. Six additional Phase 2 clinical trials of FavId in other types of B-cell NHL are either ongoing or expected to begin during 2005. Two of these clinical trials will be conducted under separate physician-sponsored Investigational New Drug Applications, or INDs, in the United States. One of these will be conducted as a physician-sponsored clinical trial in Switzerland. We currently retain exclusive worldwide commercialization rights to FavId.

Researchers have been conducting clinical trials of active immunotherapies in patients with B-cell NHL for more than a decade. The results of clinical trials at the Stanford University Medical Center and the National Cancer Institute, or NCI, suggest that active immunotherapies similar to FavId, when used following chemotherapy, may induce long-term remission and improve survival time among indolent B-cell NHL patients. Despite the promising results of these trials, we believe manufacturing limitations have hindered commercialization of these immunotherapies. We have developed a proprietary technology that we believe enables us to overcome historical limitations to the manufacturing and commercialization of active immunotherapies for B-cell NHL. We believe that our technology will enable us to manufacture FavId in a timely and cost-effective manner and allow us to offer a treatment option not currently available to physicians and patients.

We believe our active immunotherapy expertise and proprietary manufacturing technology will enable us to develop additional product candidates for other oncology indications, such as T-cell lymphoma, and for autoimmune diseases. We are currently developing a second product candidate, FAV-201, for the treatment of T-cell lymphoma and intend to initiate a Phase 1/2 clinical trial in the second half of 2005. We also intend to initiate preclinical studies to identify additional product candidates for the treatment of autoimmune diseases, with an initial focus on multiple sclerosis, during the first half of 2005.

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Market Opportunity for FavId

The American Cancer Society estimates that 54,370 people will be diagnosed with NHL in the United States in 2004, and the NCI has most recently estimated that approximately 332,000 patients suffer from this disease. Approximately 85% of NHL patients have B-cell NHL. We believe that approximately half of these patients have the slow-growing, or indolent, form of the disease. The majority of the remaining patients have a faster growing form of the disease, commonly referred to as aggressive NHL. A number of therapies are used to treat indolent B-cell NHL, including Rituxan, which had sales in the United States of over $1.3 billion in 2003 for indolent B-cell NHL and other indications. Despite the benefits of current therapies, indolent B-cell NHL remains an incurable disease that is inevitably fatal.

Our Clinical Development Program

We initiated a pivotal Phase 3 clinical trial of FavId in July 2004. We anticipate this trial will be conducted at 65 or more sites and require 342 evaluable patients. Similar to our Phase 2 clinical trial involving Rituxan, this trial is open to patients with the most prevalent form of indolent lymphoma, known as follicular B-cell NHL. Eligible patients include those who have received no prior treatment, referred to as treatment-naïve, and those who are relapsed from or refractory to prior therapies. Patients are considered relapsed if their lymphoma has returned after a response to prior therapy. Patients are considered refractory if they have not responded to prior treatments. Our Phase 3 clinical trial is designed to evaluate FavId's ability to extend the TTP in patients following treatment with Rituxan. We believe this regimen will provide patients with indolent B-cell NHL the option of an all-biologic therapy that avoids many of the side effects associated with chemotherapy.

We initiated a multi-center, open-label Phase 2 clinical trial of FavId in patients who were eligible for treatment with Rituxan in June 2002. Initially, this trial was limited to relapsed or refractory patients who had previously undergone treatment with Rituxan, chemotherapy or both. In April 2003, we expanded the entry criteria to include treatment-naïve patients. Patient enrollment for the trial was completed in December 2003. Out of a total of 103 patients who received Rituxan in this study, sufficient quantities of FavId were available for 99 patients. At a median observation time of approximately one year, 70% of these patients were progression free.

A comparison of the time to progression for 26 patients in our Phase 2 clinical trial who were relapsed or refractory to chemotherapy and who then received Rituxan followed by FavId can be made with the results of a study in a similar patient population treated with Rituxan alone as reported by Dr. Thomas E. Witzig in the Journal of Clinical Oncology in May 2002. In Dr. Witzig's study, 58 follicular B-cell NHL patients relapsed or refractory from prior chemotherapy were treated with Rituxan alone. A preliminary analysis of our data show a positive trend to a longer TTP in patients treated with Rituxan followed by FavId compared to patients treated with Rituxan alone. FavId was also generally safe and well-tolerated, with injection site reactions as the most frequent side effect.

A similar comparison of the 39 treatment-naïve patients enrolled in our Phase 2 clinical trial can be made with the results of a study published by Dr. John D. Hainsworth in the Journal of Clinical Oncology in October 2002. In this publication, Dr. Hainsworth reported results for 60 treatment-naïve patients who received Rituxan every six months for two years or until their disease progressed. We believe our preliminary data show a trend towards an equivalent TTP in patients treated with one course of Rituxan followed by FavId compared to patients treated with a course of Rituxan alone every six months for two years. The positive interim results found in our Phase 2 clinical trial do not guarantee final results, and our positive initial assessment of FavId in this clinical trial could differ from our assessment following completion of the clinical trial.

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In September 2002, we completed patient enrollment in a multi-center, open-label Phase 2 clinical trial evaluating FavId as a single agent. The trial included 27 evaluable indolent B-cell NHL patients who were either relapsed from or refractory to prior treatments. The trial was designed to determine whether the use of FavId alone could stimulate an immune response and whether the response would result in a clinical benefit. One patient had a complete response and three patients had partial responses, meaning at least a 50% reduction in tumor size. Four patients demonstrated a minor response, defined as a 25% to 50% reduction in their tumor burden, and 15 additional patients demonstrated stable disease. The median TTP for these 27 patients was determined to be 12.3 months. As of December 6, 2004, six patients remained progression free and are continuing to receive FavId injections. At 28 months from the start of FavId, one patient, while in remission, died from a non- lymphoma-related cause. The progression free status of these patients ranges from 23 months to 38 months. FavId was generally safe and well-tolerated, with injection site reactions as the most frequent side effect.

We consider these results to be encouraging compared to results from similar patients treated with other therapies. In the clinical trial conducted by Dr. Witzig, patients with indolent B-cell NHL treated with Rituxan alone had a median TTP of 10.1 months. Similarly, in a trial involving indolent B-cell NHL reported by Dr. Peter McLaughlin in the Journal of Clinical Oncology in August 1998, patients treated with Rituxan alone had a TTP of 9.0 months. Our data suggest that FavId results in a TTP that is at least as long as that reported for Rituxan.

Our Strategy

Our goal is to become a leading biopharmaceutical company focused on the research, development and commercialization of targeted immunotherapies for the treatment of cancer and other diseases of the immune system. Key elements of our strategy for achieving this goal are to:

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complete clinical development and obtain regulatory approval for FavId;



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utilize our proprietary technology to develop additional product candidates;



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retain commercialization rights to our oncology products; and



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expand our oncology product portfolio through in-licensing and acquisitions.

Risks Related to Our Business

We are at an early stage in the development of our company with a limited operating history and have had no revenues derived from operations. We have experienced significant operating losses since our inception, and we expect to incur substantial additional losses. If we are unable to successfully commercialize our lead product candidate, FavId, we may never be profitable and may have to cease operations.

Corporate Information

We were incorporated in the State of Delaware in January 2000. Our principal executive offices are located at 10421 Pacific Center Court, Suite 150, San Diego, California 92121. Our telephone number is (858) 526-8000. Our website is www.favrille.com. Information contained in our website is not incorporated by reference into and does not constitute part of this prospectus.

FavId®, Favrille and our logo are our trademarks, and we have applied to register Favrille and our logo with the United States Patent and Trademark office and to register some of our trademarks in other countries. All other trademarks or tradenames appearing in this prospectus are the property of their respective owners.

Unless the context indicates otherwise, as used in this prospectus, the terms "Favrille," the "Company," "we," "us" and "our" refer to Favrille, Inc.

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The Offering

The number of shares of common stock to be outstanding immediately after the offering is based on the number of shares of common stock outstanding as of September 30, 2004. This number does not include, as of September 30, 2004:

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1,052,360 shares of common stock issuable upon the exercise of stock options outstanding, with a weighted-average exercise price of approximately $0.63 per share. From October 1, 2004 through January 24, 2005, we granted options to purchase an aggregate of 120,910 shares of common stock with a weighted-average exercise price of approximately $0.73 per share;



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47,057 shares of common stock issuable upon the exercise of warrants outstanding, with a weighted-average exercise price of approximately $5.01 per share;



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216,436 additional shares of common stock reserved for future issuance under our Amended and Restated 2001 Equity Incentive Plan. In October and December 2004, our board of directors authorized a 559,036 share increase to the existing option pool. As such, as of December 31, 2004, 683,282 shares of common stock remained available for future issuance or grant under our equity incentive plan. The share reserve as of December 31, 2004 has not been reduced by the 28,430 committed shares noted above; and



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720,000 shares of common stock reserved for future issuance under our 2005 Non-Employee Directors' Stock Option Plan and 2005 Employee Stock Purchase Plan, which we have adopted effective upon completion of this offering.

Except as otherwise indicated, all information contained in this prospectus assumes:

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a 1-for-5.1875 reverse split of our common stock effected on January 21, 2005;



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the automatic conversion of all of our outstanding shares of preferred stock into 12,177,316 shares of common stock upon the completion of this offering;



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no exercise of the underwriters' over-allotment option; and



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the filing of our amended and restated certificate of incorporation upon completion of this offering.

Certain of our existing stockholders, including Alloy Corporate 2000, L.P., Forward Ventures IV L.P., Sanderling Venture Partners V, L.P., William Blair Capital Partners VII, and their affiliates, have indicated an interest in purchasing up to an aggregate of $18.6 million of common stock in this offering. However, because indications of interest are not binding agreements or commitments to purchase, these stockholders may elect not to purchase any shares in this offering.

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SUMMARY FINANCIAL DATA

The following summary financial data should be read in conjunction with "Selected Financial Data," "Management's Discussion and Analysis of Financial Condition and Results of Operations" and our financial statements and accompanying notes included elsewhere in this prospectus. The summary financial data for the years ended December 31, 2001, 2002 and 2003 and the summary balance sheet data as of December 31, 2003 are derived from our audited financial statements, which are included elsewhere in this prospectus. The summary financial data for the period from January 21, 2000 (inception) to December 31, 2000 are derived from our audited financial statements, which are not included in this prospectus. The financial information for the nine months ended September 30, 2003, and as of and for the nine months ended September 30, 2004, was derived from our unaudited financial statements for such periods and dates, which appear elsewhere in this prospectus. Our historical results are not necessarily indicative of our future results.

The pro forma as adjusted balance sheet data reflect the balance sheet data as of September 30, 2004 adjusted for the sale of 6,000,000 shares of common stock in this offering at an assumed initial public offering price of $7.50 per share, after deducting estimated underwriting discounts and commissions and estimated offering expenses payable by us and the automatic conversion of all preferred stock into common stock upon completion of this offering.

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See Note 1 of Notes to Financial Statements for a description of the method used to compute pro forma basic and diluted net loss per share and number of shares used in computing historical and pro forma basic and diluted net loss per share.

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RISK FACTORS

You should consider carefully the risk factors described below, together with the other information contained in this prospectus, before you decide whether to invest in shares of our common stock. If any of the following risks actually occur, our business, financial condition, results of operations and future growth prospects would likely be materially and adversely affected. In these circumstances, the market price of our common stock could decline, and you may lose all or part of your investment in our common stock.

Risks Related to the Development of Our Product Candidates

We are dependent on the success of our lead product candidate, FavId, and we cannot be certain that it will be commercialized.

We have expended significant time, money and effort in the development of our lead product candidate, FavId, which is still in clinical development, has not yet received regulatory approval and may never be commercialized. In order to commercialize FavId, we will need to demonstrate to the FDA and other regulatory agencies that it satisfies rigorous standards of safety and effectiveness. We initiated a pivotal Phase 3 clinical trial of FavId for the treatment of follicular B-cell NHL in July 2004.

We are also evaluating FavId for use in other B-cell NHL indications. However, even if we were to receive regulatory approval of FavId for the treatment of indolent B-cell NHL or the other indications we are exploring, our ability to successfully commercialize FavId could be jeopardized by the emergence of a competitive product that exhibits greater efficacy, longer duration of response or other benefits. In addition, because our initial regulatory and marketing strategy contemplates the administration of FavId to patients following treatment with Rituxan, the commercial opportunity for FavId may be limited by the degree to which oncologists continue to use Rituxan to treat indolent B-cell NHL. Furthermore, to the extent FavId fails to gain market acceptance for its initial indication, it may be more difficult for us to generate sufficient credibility with physicians and patients to commercialize FavId for other indications.

Other than FavId, we have only two other product development programs, which are at significantly earlier stages of development. We plan to initiate a Phase 1/2 clinical trial evaluating the safety and preliminary efficacy of a product candidate, FAV-201, from one of these programs in patients with T-cell lymphoma in the second half of 2005. During the first half of 2005, we intend to initiate preclinical studies to assess the applicability of our technology to autoimmune diseases, with an initial focus on multiple sclerosis. We cannot be certain that we will be able to successfully develop any product candidate from these development programs. We cannot be certain that the clinical development of FavId or any other product candidate in preclinical testing or clinical trials will be successful, that it will receive the regulatory approvals required to commercialize it, or that any of our other research programs will yield a product candidate suitable for entry into clinical trials. If we are unable to commercialize FavId or our other product candidates, we may be unable to generate sufficient revenues to attain or maintain profitability, our ability to raise additional capital will be impaired and our stock price may be negatively affected.

Failure to obtain product approvals by the FDA could harm our business.

We are subject to rigorous and extensive regulation by the FDA. In the United States, our product candidates cannot be marketed until they are approved by the FDA. Our biologic product candidates are in the preclinical and clinical stages of development and have not been approved for marketing in the United States. Obtaining FDA approval involves the submission, among other information, of the results of preclinical studies and clinical trials of the product candidates. We may not be able to obtain FDA approval, and, even if we are able to do so, the approval process typically takes many years and

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requires the commitment of substantial effort and financial resources. The FDA can delay, limit or deny approval of a biologic for many reasons, including:

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the FDA may not find that the biologic product candidate is sufficiently safe or effective;



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FDA officials may interpret data from preclinical testing and clinical trials in different ways than we do; and



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the FDA may not find our manufacturing processes or facilities satisfactory.

In addition, the specific active immunotherapy technology on which FavId is based is a relatively new form of cancer therapy that presents novel issues for the FDA to consider, which may make the regulatory process especially difficult.

We cannot assure you that any of our product candidates in development will be approved in the United States in a timely fashion, or at all. Failure to obtain regulatory approval of our product candidates in a timely fashion would prevent or delay us from marketing or selling any products and, therefore, from generating revenues from their sale. If this occurs, we may be unable to generate sufficient revenues to attain or maintain profitability, our ability to raise additional capital will be impaired and our stock price may be negatively affected. In addition, both before and after approval, we are subject to numerous FDA requirements covering, among other things, testing, manufacturing, quality control, labeling, advertising, promotion and export of biologics. Failure to comply with the law, including statutes and regulations, administered by the FDA, could result in, among others, any of the following actions:

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warning letters;



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fines and other civil penalties;



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unanticipated expenditures;



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delays in approving or refusal to approve a product candidate;



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product recall or seizure;



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interruption of production;



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operating restrictions;



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injunctions; and



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criminal prosecution.

Before we can seek regulatory approval of any of our product candidates, we must successfully complete clinical trials, which are uncertain.

Conducting clinical trials is a lengthy, time-consuming and expensive process, and the results of these trials are inherently uncertain. We have completed enrollment of patients in two Phase 2 clinical trials of FavId involving over 120 indolent B-cell NHL patients and are currently conducting follow-up evaluation of those patients. We initiated a pivotal Phase 3 clinical trial of FavId for the treatment of follicular B-cell NHL in July 2004 and expect to initiate an additional Phase 2 clinical trial of FavId in the first half of 2005. We estimate an 18-month patient enrollment period and an additional 18-month evaluation period for our pivotal Phase 3 clinical trial for FavId. Six additional Phase 2 clinical trials of FavId are either ongoing or expected to begin during the first half of 2005. Two of these clinical trials will be conducted under separate physician-sponsored INDs in the United States. One of these will be conducted as a physician-sponsored clinical trial in Switzerland. Sponsorship for a physician-sponsored IND of an ongoing Phase 2 clinical trial was assumed in August 2004. We are also developing FAV-201

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for the treatment of T-cell lymphoma and expect to initiate a Phase 1/2 clinical trial evaluating the safety and preliminary efficacy of FAV-201 in the second half of 2005.

We have received a Special Protocol Assessment, or SPA, from the FDA for our recently-initiated Phase 3 clinical trial. In the SPA process, the FDA reviewed the design, size and planned analysis of our Phase 3 clinical trial and provided comments regarding the trial's adequacy to form a basis with respect to effectiveness for approval of a Biologics Licensing Application, or BLA, if the trial is successful in meeting its predetermined objectives. The FDA's written agreement is binding on its review decision, except in limited circumstances, such as when a substantial scientific issue essential to determining the safety or effectiveness of a product candidate is identified after the Phase 3 clinical trial is commenced. Even if a BLA is filed, there is no guarantee that the application will be approved. Any change to the protocol for our Phase 3 clinical trial included in the SPA would require prior FDA approval, which could delay our ability to implement such change.

In addition, despite having received an SPA, we may be required to conduct an additional Phase 3 clinical trial of FavId for the treatment of indolent B-cell NHL before we can apply for regulatory approval. Although the FDA typically requires successful results in two Phase 3 clinical trials to support marketing approval, the FDA has, on several occasions, approved products based on a single Phase 3 clinical trial that demonstrates a high level of statistical significance where there is an unmet need for a life-threatening condition. We currently plan to seek FDA approval of FavId based on our recently-initiated Phase 3 clinical trial alone. In the event that the FDA requires the results of a second Phase 3 clinical trial before accepting a BLA or before granting marketing approval of FavId, our launch of FavId would be delayed, possibly by several years, and we would incur significant costs in conducting the additional trial.

Completion of necessary clinical trials may take several years or more. Our commencement and rate of completion of clinical trials may be delayed by many factors, including:

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ineffectiveness of the product candidate, or perceptions by physicians that the product candidate is not safe or effective for a particular indication;



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inability to manufacture sufficient quantities of the product candidate for use in clinical trials;



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delay or failure in obtaining approval of our clinical trial protocols from the FDA;



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slower than expected rate of patient recruitment and enrollment;



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inability to adequately follow and monitor patients after treatment;



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difficulty in managing multiple clinical sites;



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unforeseen safety issues; and



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government or regulatory delays.

Even if we achieve positive interim results in clinical trials, these results do not necessarily predict final results, and positive results in early trials may not be indicative of success in later trials. A number of companies in the pharmaceutical industry have suffered significant setbacks in advanced clinical trials, even after promising results in earlier trials. Negative or inconclusive results or adverse medical events during a clinical trial could cause us to repeat or terminate a clinical trial or require us to conduct additional trials. Our clinical trials may be suspended at any time for a variety of reasons, including if the FDA or we believe the patients participating in our trials are exposed to unacceptable health risks or if the FDA finds deficiencies in the conduct of these trials.

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Failures or perceived failures in our clinical trials will directly delay our product development and regulatory approval process, damage our business prospects, make it difficult for us to establish collaboration and partnership relationships, and negatively affect our reputation and competitive position in the pharmaceutical community.

Failure to enroll patients in our clinical trials may cause delays in developing FavId or any other product candidate.

We may encounter delays in development and commercialization, or fail to obtain marketing approval, of FavId or any other product candidate that we may develop if we are unable to enroll enough patients to complete clinical trials. Our ability to enroll sufficient numbers of patients in our clinical trials depends on many factors, including the size of the patient population, the nature of the protocol, the proximity of patients to clinical sites, the eligibility criteria for the trial and competing clinical trials. We have from time to time experienced slower-than-expected patient enrollment in our clinical trials. Delays in planned patient enrollment may result in increased costs and harm our ability to complete our clinical trials and obtain regulatory approval.

The development of FavId requires the continued availability of two FDA-approved drugs: GM-CSF and Rituxan.

Administration of FavId requires an adjuvant to enhance the immune response. An adjuvant is a substance that is used to enhance the immune response. We use a white blood cell growth factor known as GM-CSF, which is commercially available solely from Berlex Laboratories, Inc., as an adjuvant for FavId. We currently rely on purchase orders to purchase GM-CSF for use in our clinical trials and do not have a supply agreement with Berlex. GM-CSF is an FDA-approved and commercially available drug that may be purchased by physicians. Our current strategy for the initial commercialization of FavId involves the administration of FavId following treatment with Rituxan. Rituxan is a passive immunotherapy for patients with NHL, which is also FDA-approved and is commercially available solely from Genentech, Inc. and Biogen Idec Inc. We currently rely on physicians to order and administer Rituxan to patients prior to the administration of FavId in our registration trial. If GM-CSF or Rituxan were to become unavailable as a result of regulatory actions, supply constraints or other reasons, our ability to continue the clinical development of FavId would be jeopardized.

Risks Related to Our Financial Results and Need for Financing

We have incurred significant operating losses since inception and anticipate that we will continue to incur substantial losses and negative cash flow from operations for the foreseeable future.

We are a development stage company with a limited operating history. We have financed our operations through private placements of preferred stock and equipment and leasehold debt financing. We have incurred losses in each year since our inception in 2000. Net losses were $18.4 million for the nine months ended September 30, 2004, $13.3 million in 2003, $7.2 million in 2002, $3.8 million in 2001 and $1.0 million in 2000. As of September 30, 2004, we had an accumulated deficit of $71.9 million. These losses, among other things, have had and will continue to have an adverse effect on our stockholders' equity and working capital. We expect to incur substantial operating losses for at least the next several years. This is due primarily to the expansion of our clinical trials and research and development programs and, to a lesser extent, general and administrative expenses. We also have substantial lease and debt obligations related to our new manufacturing and headquarters facilities impacting our operating expenses. We expect that our losses will fluctuate from quarter to quarter and that these fluctuations may be substantial. We cannot guarantee that we will successfully develop,

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manufacture, commercialize or market any products. As a result, we cannot guarantee that we will ever achieve or sustain product revenues or profitability.

We currently have no source of revenue and may never become profitable.

Our ability to become profitable will depend upon our ability to generate revenue. To date, FavId has not generated any revenue, and we do not know when or if FavId will generate revenue. Our ability to generate revenue depends on a number of factors, including our ability to:

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successfully complete clinical trials for FavId;



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obtain regulatory approval for FavId, including regulatory approval for our commercial scale manufacturing facility and process;



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manufacture commercial quantities of FavId at acceptable cost levels; and



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successfully market and sell FavId.

We do not anticipate that we will generate revenues until 2008, at the earliest. Further, we do not expect to achieve profitability for at least several years after generating material revenues. If we are unable to generate revenue, we will not become profitable, and we may be unable to continue our operations.

We will need substantial additional funds to continue operations, which we may not be able to raise on favorable terms, or at all.

We will need substantial additional funds for existing and planned preclinical studies and clinical trials, to continue research and development activities, for lease and debt obligations related to our manufacturing and headquarter facilities, and to establish manufacturing and marketing capabilities for any products we may develop. In addition, because we do not expect to generate revenues from the sale of our product candidates for several years, or at all, we will also need to raise additional capital to fund our operations.

We believe that the net proceeds from this offering, together with interest thereon and our existing cash and cash equivalents, will be sufficient to meet our projected operating requirements for at least the next 24 months. We will need to raise additional funds in order to commercialize FavId, including the completion of the construction and qualification of a commercial scale manufacturing facility. Our forecast of the period of time through which our financial resources will be adequate to support our operations is a forward-looking statement and involves risks and uncertainties, and actual results could vary as a result of a number of factors, including the factors discussed elsewhere in this "Risk Factors" section of this prospectus. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we currently expect.

Our future capital requirements and the adequacy of our available funds will depend on many factors, including, but not limited to:

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magnitude and cost of our product development efforts and other research and development activities;



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rate of progress toward obtaining regulatory approval for our product candidates;



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costs of filing, prosecuting, defending and enforcing our patent claims and other intellectual property rights;

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our ability to establish and maintain collaborative, licensing or other arrangements for the development, sale, marketing or distribution of our product candidates and the terms of those arrangements;



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effects of competing technological and market developments; and



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the success of the commercialization of FavId.

Future capital requirements will also depend on the extent to which we acquire or invest in businesses, products and technologies, but we currently have no commitments or agreements relating to any of these types of transactions.

We may seek to access the public or private equity markets whenever conditions are favorable, even if we do not have an immediate need for additional capital at that time. Additional funding may not be available to us, and, if available, may not be on acceptable terms. If we raise additional funds by issuing equity securities, stockholders will incur immediate dilution. If adequate funds are not available to us, we may be required to delay, reduce the scope of, or eliminate one or more of our research, development and clinical activities. Alternatively, we may need to seek funds through arrangements with collaborative partners or others that require us to relinquish rights to technologies or product candidates that we would otherwise seek to develop or commercialize ourselves. Any of these events could have a material adverse effect on our business, results of operations, financial condition or cash flow.

We are recording non-cash compensation expense that may result in an increase of our net losses for a given period.

Stock-based compensation represents an expense associated with the recognition of the difference between the deemed fair value of common stock at the time of an option grant or stock issuance and the option exercise price or price paid for the stock. Stock-based compensation is amortized over the vesting period of the option or issuance. As of September 30, 2004, deferred stock-based compensation related to option grants to our employees and non-employee directors totaled $8.2 million, which is being amortized to expense on a straight-line basis as the options or stock are earned, generally over a period of four years. Also, we have granted options to consultants which, for compensation purposes, must be remeasured at each reporting date during the vesting period. This remeasurement and the corresponding effect on the related expense may result in an increase in our net losses for a given period.

Other Risks Related to Our Business and Industry

We currently depend on single source suppliers for critical raw materials for manufacturing. The loss of these suppliers could delay our clinical trials or prevent or delay commercialization of FavId.

We currently depend on single source suppliers for critical raw materials used in the manufacture of FavId. In particular, our manufacturing process for FavId requires a foreign protein derived from shellfish that is known as keyhole limpet hemocyanin, or KLH. We purchase KLH from biosyn Arzneimittel GmbH, or biosyn, which is currently the only supplier of KLH that has submitted the required filing, known as a drug master file, with the FDA. In November 2004, we entered into an eight-year supply and license agreement with biosyn under which biosyn has agreed to supply us with KLH and we have committed to minimum initial and annual KLH purchase requirements. We made a $50,000 initial payment to biosyn under the agreement and we committed to purchase $30,000 of raw material in December 2004 and an additional $205,000 of raw material in January and May 2005. An additional aggregate of up to $300,000 will be due upon the achievement of certain milestones, the

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timing of which are not known at this time. Either party may terminate the supply agreement upon a breach by the other party that is not cured within 60 days or other events relating to insolvency or bankruptcy. If we identify another supplier of KLH of suitable quality for our purposes, we will not be able to use the supplier as a second source of KLH for the commercial manufacture of FavId unless the KLH is tested to be comparable to the existing KLH.

In addition, we depend on a single source supplier for the cell growth media we use to produce FavId. We purchase this material from Expression Systems LLC, which in turn obtains several of the components used in the cell growth media from sole suppliers. We currently rely on purchase orders to obtain this material and do not have a supply agreement with Expression Systems. We intend to qualify a second source for the cell growth media but may not be able to do so.

Establishing additional or replacement suppliers for these materials may take a substantial amount of time. In addition, we may have difficulty obtaining similar materials from other suppliers that are acceptable to the FDA. If we have to switch to a replacement supplier, we may face additional regulatory delays and the manufacture and delivery of FavId, or any other product candidates that we may develop, could be interrupted for an extended period of time, which may delay completion of our clinical trials or commercialization. If we are unable to obtain adequate amounts of these materials, our clinical trials will be delayed. In addition, we will be required to obtain regulatory clearance from the FDA to use different materials that may not be as safe or as effective. As a result, regulatory approval of FavId, or any other product candidates that we may develop, may not be received at all.

We rely on third parties to conduct our clinical trials. If these third parties do not successfully carry out their contractual duties or meet expected deadlines, we may be delayed or may not be able to obtain regulatory approval for or commercialize FavId or any other product candidates that we may develop.

We expect our pivotal Phase 3 clinical trial of FavId for the treatment of follicular B-cell NHL to be conducted at 65 or more sites in the United States and to require at least 342 evaluable patients. We expect that at least three clinical trials of FavId will be conducted under the direction of a physician sponsor, rather than under our supervision. We do not have the ability to independently conduct clinical trials for FavId, or any other product candidate that we may develop, and we must rely on third parties, such as medical institutions and clinical investigators, including physician sponsors, to conduct our clinical trials. In particular, we will rely on these parties to recruit and enroll patients in our clinical trials. We also rely on third-party couriers to transport patient tissue samples and FavId. If any of the third parties upon whom we rely to conduct our clinical trials or transport patient tissue samples and immunotherapies do not comply with applicable laws, successfully carry out their obligations or meet expected deadlines, and need to be replaced, our clinical trials may be extended, delayed or terminated.

If the quality or accuracy of the clinical data obtained by medical institutions and clinical investigators, including physician sponsors, is compromised due to their failure to adhere to applicable laws, our clinical protocols or for other reasons, we may not be able to obtain regulatory approval for or successfully commercialize FavId, or any other product candidates that we may develop. If any of our relationships with any of these organizations or individuals terminates, we believe that we would be able to enter into arrangements with alternative third parties. However, replacing any of these third parties would delay our clinical trials and could jeopardize our ability to commercialize FavId and our other product candidates on a timely basis, or at all.

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Even if we obtain regulatory approval, we will continue to be subject to extensive government regulation that may cause us to delay the introduction of our products or withdraw our products from the market.

Even if we obtain regulatory approval for FavId or our other product candidates, we will still be subject to extensive regulation. These regulations will impact many aspects of our operations, including production, record keeping, quality control, adverse event reporting, storage, labeling, advertising, promotion and personnel. In addition, the later discovery of previously unknown problems may result in restrictions of the product candidates, including their withdrawal from the market. Furthermore, regulatory approval may subject us to ongoing requirements for post-marketing studies. If we or any third party that we involve in our operations fail to comply with any continuing regulations, we may be subject to, among other things, product seizures, recalls, fines or other civil penalties, injunctions, suspensions or revocations of marketing licenses, operating restrictions and criminal prosecution.

Before we can obtain marketing approval for or commercially distribute FavId, the FDA and the California Department of Health Services must find our manufacturing facility and process satisfactory.

Our manufacturing methods, equipment and processes must comply with the FDA's current Good Manufacturing Practices, or cGMP, requirements. We may also need to perform extensive audits of vendors, contract laboratories and suppliers. The cGMP requirements govern, among other things, record keeping, production processes and controls, personnel and quality control. We have only undertaken initial steps towards achieving compliance with these regulatory requirements. Additional steps will require expenditure of significant time, money and effort. We cannot predict the likelihood that the FDA will find our facility satisfactory, even if we believe that we have taken the necessary steps to achieve compliance. If we fail to comply with these requirements or fail to pass a pre-approval inspection of our manufacturing facility in connection with an application to obtain marketing approval for FavId or another product candidate, we would not receive regulatory approval, and we would be subject to possible regulatory action.

We plan to manufacture FavId for our recently-initiated Phase 3 and for the planned and ongoing Phase 1/2 clinical trials at our facility in San Diego. Our manufacturing facility is subject to the licensing requirements of the California Department of Health Services. Our facility was inspected and licensed by the California Department of Health Services. Our facility is subject to re-inspection at any time. Failure to maintain a license from the California Department of Health Services or to meet the inspection criteria of the California Department of Health Services would disrupt our manufacturing processes and prevent us from supplying FavId to patients. If an inspection by the California Department of Health Services indicates that there are deficiencies in our manufacturing process, we could be required to take remedial actions at potentially significant expense, and our facility may be temporarily or permanently closed.

We will need to construct and qualify a commercial scale manufacturing facility in order to commercialize FavId or any other product candidates that we may develop. Preparing a facility for commercial manufacturing may involve unanticipated delays and the costs of complying with FDA regulations may be significant. In addition, any material changes we make to the manufacturing process after approval may require approval by the FDA and state regulatory authorities. Obtaining these approvals is a lengthy, involved process, and we may experience delays that could limit our ability to manufacture commercial quantities, increase our costs and adversely affect our business.

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We may experience difficulties in manufacturing FavId or any other product candidates that we may develop, which could prevent us from completing our ongoing clinical trials and commercializing these product candidates.

Manufacturing FavId is a complex, multi-step process that requires us to expend significant time, money and effort in production, record keeping and quality systems to assure that FavId will meet product specifications and other regulatory requirements. To date, we have manufactured FavId only for use in Phase 2 clinical trials and have no experience in manufacturing FavId for the number of patients that we expect to enroll in our Phase 3 clinical trial or for the commercial quantities that might be required if we receive regulatory approval. In particular, we cannot be sure that we will be able to manufacture FavId at a cost that would enable commercial use. We may experience any of the following problems in our efforts to manufacture our product candidates for our expanding clinical trials or on a commercial scale:

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failure to obtain a sufficient supply of key raw materials;



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difficulties in completing the development and validation of the specialized assays required to ensure the consistency of our product candidates, including FavId;



•

difficulties in obtaining adequate tumor samples from treating physicians and hospitals;



•

difficulties in manufacturing FavId for multiple patients simultaneously;



•

difficulties in the timely shipping of tumor samples to us or in the shipping of FavId to the treating physicians due to errors by third-party couriers, transportation restrictions or other reasons;



•

failure to ensure adequate quality control and assurance in the manufacturing process as we increase the production quantities of FavId;



•

difficulties in establishing and effectively managing a commercial-scale manufacturing facility;



•

failure to comply with regulatory requirements, such as FDA regulations and environmental laws;



•

significant changes in regulatory requirements;



•

damage to or destruction of our manufacturing facility or equipment; and



•

shortages of qualified personnel.

In addition, because our manufacturing process only begins upon our receipt of a patient's tumor biopsy, we cannot produce inventory reserves of our product candidate to be stored in anticipation of any of these potential manufacturing problems. The failure to produce an adequate supply of FavId could delay our clinical trials and, in turn, delay submission of a BLA for FavId and commercial launch. Similarly, any difficulties we experience in the manufacture and supply of other product candidates, such as FAV-201, would delay the clinical trials of those product candidates.

If our manufacturing facility is damaged or destroyed, our ability to manufacture products will be significantly affected, which could delay or prevent completion of our clinical trials and commercialization of FavId or any other product candidates that we may develop.

We currently rely on the availability and condition of our manufacturing facility in San Diego to manufacture FavId. We lease the property where this facility is located under a lease agreement that expires August 31, 2018 but may be extended at our option for two additional five-year periods. After

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that time, we may not be able to negotiate a new lease for our facility. If the facility or our equipment in the facility is damaged or destroyed, we will not be able to quickly or inexpensively replace our manufacturing capacity. This would significantly affect our ability to complete clinical trials of, and to manufacture and commercialize, FavId, or any other product candidates that we may develop.

In addition, our facilities have been subject to electrical blackouts as a result of a shortage of available electrical power. Although we have back-up emergency power generators to cover energy needs for key support systems, a lengthy outage could disrupt the operations of our facilities and clinical trials. While we carry business interruption insurance, this insurance may not be adequate. Any significant business interruption could cause delays in our product development and harm our business.

If we do not develop a sufficient sales and marketing force or enter into agreements with third parties to sell and market FavId, we may not be able to successfully commercialize our products, which would limit our ability to earn product revenues.

We plan to retain exclusive worldwide rights to FavId for oncology indications at least through the completion of our BLA filing with the FDA for approval to market FavId in the United States. If we are successful in obtaining BLA approval or foreign marketing approval for FavId, we will need to establish sales and marketing capabilities. In the United States, we plan to do this either by establishing our own sales force or by entering into a co-promotion arrangement with a sales and distribution partner. Outside of the United States, we plan to establish strategic collaborations for the development and marketing of FavId.

We do not presently possess the resources or experience necessary to market FavId or our other product candidates ourselves, and we currently have no arrangements for the promotion or distribution of our product candidates. Our future commercial success will depend on our ability to establish our own sales and marketing infrastructure or to collaborate with third parties that have greater sales and marketing experience and resources. Developing effective internal sales and marketing capabilities, which would include the hiring of a sales force, would require a significant amount of our financial resources and time. We may be unable to establish and manage an effective sales force in a timely or cost-effective manner, or at all, and any sales force we do establish may not be capable of generating demand for FavId or any other product candidate we may develop. In addition, if we cannot enter into co-promotion arrangements in the United States, or other strategic collaborations for the development and marketing of FavId in other countries, in a timely manner and on acceptable terms, we may not be able to successfully commercialize FavId or any other product candidate that we may develop.

To the extent that we enter into arrangements with third parties to perform sales, marketing and distribution services, our product revenues are likely to be lower than if we directly marketed and sold FavId, or any other product candidates that we may develop. If we are unable to establish adequate sales, marketing and distribution capabilities, independently or with others, we will not be able to generate product revenue and will not become profitable.

If physicians and patients do not use any of our products that may be approved, our ability to generate revenue in the future will be limited.

If approved, FavId and other product candidates that we may develop may not gain market acceptance among physicians, healthcare payors, patients and the medical community. Demand for any approved product that we may develop will depend on many factors, including:

•

our ability to provide acceptable evidence of safety and efficacy;



•

convenience and ease of administration;

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•

availability of alternative treatments;



•

cost effectiveness;



•

continuing widespread use of Rituxan to treat our initial target disease market;



•

effectiveness of our regulatory and marketing strategies;



•

prevalence and severity of adverse side effects;



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publicity concerning our products or competitive products; and



•

our ability to obtain third-party coverage or reimbursement.

Furthermore, to the extent FavId fails to gain market acceptance for its initial indication, it may be more difficult for us to generate sufficient credibility with physicians and patients to commercialize FavId for other indications.

If we are unable to obtain acceptable prices or adequate coverage and reimbursement from third-party payors for FavId, or any other product candidates that we may develop, our revenues and prospects for profit