SECURITIES AND EXCHANGE COMMISSION

Amendment No. 3

717 Potter Street, Suite 100

Dino Dina, M.D.

          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 of 1933, check the following box.     o

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

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

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

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

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

PROSPECTUS SUMMARY

      This summary highlights what we believe is the most important information about Dynavax and the transaction. This summary does not contain all the information that you should consider before buying shares in this offering. Before you decide to invest in our common stock, we urge you to read the entire prospectus carefully, including the risk factors and consolidated financial statements and related notes included in this prospectus.

Our Business

      We discover, develop and intend to commercialize innovative products to treat and prevent allergies, infectious diseases and chronic inflammatory diseases. Our clinical development programs are based primarily on proprietary short sequences of synthetic deoxyribonucleic acid, or DNA, which redirect the immune system’s response to infectious pathogens and enhance its ability to fight disease and control chronic inflammation. Because these DNA sequences stimulate an immune system response, we call them immunostimulatory sequences, or ISS. Based on results from Phase II trials, we plan to initiate Phase III trials for two ISS-based product candidates in 2004. We have a third product candidate in early Phase II trials and a number of earlier stage clinical and preclinical programs. We retain full commercial rights for all of our product candidates.

Lead Product Candidates

      Our lead product candidates, which are based on a single proprietary ISS, address large market segments and we believe they provide significant advantages over current therapies. Our lead product candidates include:

	•	AIC for Ragweed Allergy. We have developed a novel injectable product candidate to treat ragweed allergy that we call AIC. Ragweed allergy is the most common seasonal allergy in North America. Unlike existing products, which treat chronic ragweed allergy symptoms, AIC targets the underlying cause of ragweed-induced seasonal allergic rhinitis. We are currently planning a two-year, multi-site Phase IIb study to evaluate the efficacy of AIC, which we anticipate will provide data to support approval in the U.S., and plan to begin enrolling patients in the first quarter of 2004. AIC has completed ten Phase I and Phase II trials to date involving more than 175 treated patients and appears to be well tolerated. In Phase II trials AIC has provided evidence of clinical improvement in allergy symptoms, which suggests that AIC may be effective in treating ragweed allergy.
	•	Hepatitis B Prophylaxis. We are nearing completion of two Phase II trials and are currently planning to initiate Phase III trials outside of the U.S. in 2004 for our hepatitis B vaccine. In Phase I and Phase II trials our hepatitis B vaccine induced more rapid immunity with fewer immunizations compared to currently available vaccines. We believe that our hepatitis B vaccine has the potential to increase efficacy achieved in the field, decreasing the spread of hepatitis B. We intend to commercialize our hepatitis B vaccine only outside the U.S.
	•	Asthma. Our inhaled therapeutic product candidate for asthma is in a pilot Phase II trial. Results from our Phase I trial demonstrated that our product candidate was well tolerated and may have the potential to suppress both clinical symptoms and the underlying inflammatory response associated with asthma. Our asthma product candidate may confer long-term relief following a single course of administration, providing advantages over current treatments, which require chronic use.

      The clinical trials process is lengthy and expensive and outcomes are uncertain. Even if earlier trials yield encouraging results, subsequent trials can fail for a variety of reasons, including lack of efficacy or safety issues. In addition, the FDA has requested companies to repeat clinical trials, conduct additional studies or suspend clinical development altogether based upon its independent review of clinical trials data. We do not believe any of our product candidates will be commercially available, if approved, until 2007, at the earliest.

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Other Product Candidates

      Beyond these lead product candidates, we have an ISS-based cancer therapeutic in Phase I trials and preclinical programs targeting additional allergies, therapies to treat viral diseases and improved, or next generation, vaccines using our ISS technology. We have also developed a number of new types of proprietary ISS molecules and formulations that make use of the different ways in which the innate immune system responds to ISS. In addition, we are developing drugs based on a novel class of small molecules called thiazolopyrimidines, or TZPs, for the treatment of certain chronic inflammatory diseases.

Benefits of ISS

      We believe ISS have the following benefits:

	•	ISS work by changing or reprogramming the immune system responses that cause disease, rather than just treating the symptoms of disease;
	•	ISS influence immune system responses in targeted and highly specific ways by redirecting the response of only certain immune system cells involved in specific diseases. As a result, ISS do not alter the ability of the immune system to mount an appropriate response to other infecting pathogens or cause a generalized activation of the immune system, which might otherwise give rise to an autoimmune response; and
	•	ISS, in conjunction with allergens or antigens, establish populations of special cells called memory cells. These memory cells allow the immune system to respond appropriately to future encounters with these specific pathogens or allergens, leading to long-lasting therapeutic effects.

Strategy

      Our goal is to become a leading biopharmaceutical company focused on discovering, developing and commercializing therapeutics for the treatment of allergies, infectious diseases and chronic inflammatory diseases. The key elements of our business strategy include:

	•	completing the development and commercialization of our lead product candidates;
	•	continuing to advance and build our product portfolio focused on allergies, infectious diseases and chronic inflammatory diseases;
	•	continuing the development of our proprietary ISS technologies to further expand the versatility and potency of our second generation product candidates;
	•	maintaining ownership of lead product candidates, generally through demonstration of clinical efficacy;
	•	selectively establishing corporate collaborations with global pharmaceutical and biotechnology companies to assist in the further joint development and commercialization of our products; and
	•	potentially building a small direct sales organization targeting narrow specialty or therapeutic areas, where feasible.

Other Information

      We were incorporated in California in August 1996 under the name Double Helix Corporation, and we changed our name to Dynavax Technologies Corporation in September 1996. We reincorporated in Delaware in 2001. Our principal offices are located at 717 Potter Street, Suite 100, Berkeley, California 94710-2722. Our telephone number is (510) 848-5100. Our Internet address is www.dynavax.com. Information contained on our website does not constitute a part of this prospectus.

      Dynavax Technologies is a registered trademark of Dynavax Technologies Corporation. Each of the other trademarks, trade names or service marks appearing in this prospectus belongs to its respective holder.

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The Offering

      The number of shares of common stock to be outstanding immediately after the offering is based upon 17,673,756 shares of common stock outstanding as of September 30, 2003. This number assumes the exchange of 15,200,000 ordinary shares of our subsidiary, Dynavax Asia Pte. Ltd., issued in October 2003, into 2,111,111 shares of our common stock upon the completion of this offering, and the automatic conversion of all shares of preferred stock outstanding as of September 30, 2003 into 13,712,128 shares of common stock upon the completion of this offering (which includes 100,102 anti-dilution shares of common stock that are issuable to existing preferred stockholders as a result of the issuance of ordinary shares of Dynavax Asia Pte. Ltd.).

      This number excludes:

	•	911,695 shares of common stock issuable upon the exercise of options outstanding as of September 30, 2003 at a weighted average exercise price of $2.13 per share;
	•	3,500,000 shares of common stock reserved for issuance under our 2004 stock incentive plan and our 2004 non-employee director option program, which will become effective upon the closing of this offering;
	•	250,000 shares of common stock available for issuance under our 2004 employee stock purchase plan, which will become effective upon the closing of this offering; and
	•	84,411 shares of common stock issuable upon the exercise of a warrant at the exercise price of $6.18 per share.

      Unless otherwise noted, all information in this prospectus assumes that:

	•	we have completed a one-for-three reverse stock split of our common stock prior to the closing of this offering;
	•	the underwriters will not exercise their option to purchase additional shares of common stock to cover over-allotments, if any;
	•	all outstanding shares of our preferred stock will have converted automatically into shares of common stock upon the closing of this offering; and
	•	we have adopted an amended and restated certificate of incorporation.

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Summary Consolidated Financial Data

      You should read the following summary financial data in conjunction with our consolidated financial statements and the related notes, “Selected Consolidated Financial Data” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included elsewhere in this prospectus.

*	Includes non-cash charges for stock-based compensation expense as follows (in thousands):

(1)	See Note 3 to our Notes to Consolidated Financial Statements for a description of pro forma net loss per share attributable to common stockholders.

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     The summary unaudited consolidated balance sheet data as of September 30, 2003 is presented below:

	•	on an actual basis;
	•	on a pro forma basis to reflect the sale of 15,200,000 shares of ordinary stock of our subsidiary, Dynavax Asia Pte. Ltd., issued in October 2003 for gross proceeds of $15.2 million.
	•	on a pro forma as adjusted basis to reflect: (1) the sale of shares of common stock offered by this prospectus at an assumed initial public offering price of $13.00 per share, after deducting underwriting discounts and commissions, estimated offering expenses payable by us and a one-time cash payment to the University of California of approximately $217,000; (2) the automatic conversion of all shares of preferred stock outstanding as of September 30, 2003 into 13,712,128 shares of common stock upon the completion of this offering (which includes 100,102 anti-dilution shares of common stock that are issuable to existing preferred stockholders as a result of the issuance of ordinary shares of Dynavax Asia Pte. Ltd.); and (3) the exchange of 15,200,000 shares of ordinary stock of Dynavax Asia Pte. Ltd. into 2,111,111 shares of our common stock upon the completion of this offering.

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RISK FACTORS

      You should carefully consider the following information about the principal risks of our business, together with the other information contained in this prospectus, before you decide to buy our common stock. If any of the following risks actually occurs, you may lose all or part of the money you paid to buy our common stock.

Risks Related to Our Early Stage of Development and Need for Financing

We have incurred substantial losses since inception and do not have any commercial products that generate revenue.

      We have experienced significant operating losses in each year since our inception in August 1996. Before 2003, almost all of our revenue resulted from payments made under collaboration agreements that have since lapsed or been mutually terminated. Currently, all of our revenue results from payments received under various government grant programs. These grants are subject to annual review based on the achievement of milestones and other factors and will terminate in 2006 at the latest. Our accumulated deficit was approximately $74.8 million as of September 30, 2003, and we anticipate that we will incur substantial additional operating losses for the foreseeable future. These losses have been, and will continue to be, principally the result of the various costs associated with our research and development activities. We expect our losses to increase primarily as a consequence of our continuing product development efforts.

      We do not have any products that generate revenue. We expect to begin Phase IIb and Phase III trials for AIC, an immunotherapy for ragweed allergy and Phase III trials for our hepatitis B vaccine in 2004. Our product candidates may never be commercialized, and we may never generate product-related revenue. Our ability to generate revenue depends upon:

	•	demonstrating in clinical trials that our product candidates are safe and effective, in particular, in the planned Phase III trials for AIC and our hepatitis B vaccine;
	•	obtaining regulatory approvals for our product candidates in the U.S. and international markets;
	•	entering into collaborative relationships on commercially reasonable terms for the development, manufacturing, sales and marketing of our product candidates, and then successfully managing these relationships; and
	•	commercial acceptance of our products, in particular AIC and our hepatitis B vaccine.

      If we are unable to generate revenues or achieve profitability, we may be required to significantly reduce or discontinue our operations or raise additional capital under adverse circumstances.

If we are unable to secure additional funding, we will have to reduce or discontinue operations.

      We believe our existing capital resources, together with the estimated net proceeds of this offering, will be sufficient to meet our anticipated cash requirements for the next 24 months. We do not believe that we will have product revenue until 2007, at the earliest. Because of the significant time and resources it will take to develop our product candidates, potentially commercialize them and generate revenue, we will require substantial additional capital resources, in addition to the proceeds of this offering, in order to continue our operations, and any such funding may not cover our costs of operations.

      We may be unable to obtain additional capital from financing sources or from agreements with collaborators on acceptable terms, or at all. If at any time sufficient capital is not available, we may be required to delay, reduce the scope of, eliminate or divest one or more of our research, preclinical or clinical programs or discontinue our operations.

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Risks Related to Our Business and Industry

All of our product candidates are unproven, and our success depends on our product candidates being approved through uncertain and time-consuming regulatory processes. Failure to prove our products safe and effective in clinical trials and obtain regulatory approvals could require us to discontinue operations.

      None of our product candidates has been proven safe and effective in clinical trials or approved for sale in the U.S. or any foreign market. Any product candidate we develop is subject to extensive regulation by Federal, state and local governmental authorities in the U.S., including the Food and Drug Administration, or FDA, and by foreign regulatory agencies. Our success is primarily dependent on our ability to obtain regulatory approval for AIC, our ragweed allergy product candidate, and our hepatitis B vaccine product candidate. We intend to commercialize our hepatitis B vaccine only outside the U.S., which will require us to seek approval from foreign regulatory agencies. Approval processes in the U.S. and in other countries are uncertain, take many years and require the expenditure of substantial resources. Product development failure can occur at any stage of clinical trials and as a result of many factors, many of which are not under our control.

      Currently, only three of our product candidates have advanced to Phase II clinical trials: AIC, our hepatitis B vaccine and our inhaled therapeutic for treatment of asthma. We have only limited clinical data for these product candidates, some of which may not be supportive of ultimate regulatory approval. In particular, in one of our Phase II trials for AIC, which was conducted in Canada in 2001 and 2002, there was no impact on clinical symptom scores or medication use in the first year of the two-year trial. We will need to demonstrate in Phase III clinical trials that each product candidate is safe and effective before we can obtain necessary approvals from the FDA and foreign regulatory agencies. We are currently planning to initiate a two-year, multi-site Phase IIb trial in the first quarter of 2004 in the U.S. for AIC. We expect to begin planning later in 2004 a confirmatory Phase III trial for AIC, which will focus on the 2005 ragweed season. We also expect to initiate Phase III trials in 2004 for our hepatitis B vaccine outside the U.S. The FDA or foreign regulatory agencies may require us to conduct additional clinical trials prior to approval in their jurisdictions.

      Many new drug candidates, including many drug candidates that have completed Phase III clinical trials, have shown promising results in early clinical trials and subsequently failed to establish sufficient safety and efficacy to obtain regulatory approval. Despite the time and money expended, regulatory approvals are never guaranteed. Failure to complete clinical trials and prove that our products are safe and effective would have a material adverse effect on our ability to eventually generate revenue and could require us to reduce the scope of or discontinue our operations.

Our clinical trials may be suspended, delayed or terminated at any time. Even short delays in the commencement and progress of our trials may lead to substantial delays in the regulatory approval process for our product candidates, which will impair our ability to generate revenue.

      We may suspend or terminate clinical trials at any time for various reasons, including regulatory actions by the FDA or foreign regulatory agencies, actions by institutional review boards, failure to comply with good clinical practice requirements and concerns regarding health risks to test subjects. In addition, our ability to conduct clinical trials for some of our product candidates, notably AIC and our asthma product candidate, is limited due to the seasonal nature of ragweed allergy and allergic asthma. Even a small delay in a trial for any of these product candidates could require us to delay commencement of the trial until the next appropriate season, which could result in a delay of an entire year. Consequently, we may experience additional delays in obtaining regulatory approval for these product candidates.

      Suspension, termination or unanticipated delays of our clinical trials for AIC or our hepatitis B vaccine may:

	•	adversely affect our ability to commercialize or market any product candidates we may develop;

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	•	impose significant additional costs on us;
	•	potentially diminish any competitive advantages that we may attain;
	•	adversely affect our ability to enter into collaborations, receive milestone payments or royalties from potential collaborators; and
	•	limit our ability to obtain additional financing on acceptable terms, if at all.

If we receive regulatory approval for our product candidates, we will be subject to ongoing FDA and foreign regulatory obligations and continued regulatory review, which may be costly and subject us to various enforcement actions.

      Any regulatory approvals that we receive for our product candidates are likely to contain requirements for post-marketing follow-up studies, which may be costly. Product approvals, once granted, may be withdrawn if problems occur after commercialization. Thus, even if we receive FDA and other regulatory approvals, our product candidates may later exhibit qualities that limit or prevent their widespread use or that force us to withdraw those products from the market.

      In addition, we or our contract manufacturers will be required to adhere to Federal regulations setting forth current good manufacturing practice. The regulations require that our product candidates be manufactured and our records maintained in a prescribed manner with respect to manufacturing, testing and quality control activities. Furthermore, we or our contract manufacturers must pass a pre-approval inspection of manufacturing facilities by the FDA and foreign regulatory agencies before obtaining marketing approval and will be subject to periodic inspection by the FDA and corresponding foreign regulatory agencies under reciprocal agreements with the FDA. Further, to the extent that we contract with third parties for the manufacture of our products, our ability to control third-party compliance with FDA requirements will be limited to contractual remedies and rights of inspection. Failure to comply with regulatory requirements could prevent or delay marketing approval or require the expenditure of money or other resources to correct. Failure to comply with applicable requirements may also result in warning letters, fines, injunctions, civil penalties, recall or seizure of products, total or partial suspension of production, refusal of the government to renew marketing applications and criminal prosecution, any of which could be harmful to our ability to generate revenue and our stock price.

Our product candidates in clinical trials rely on a single lead ISS compound, 1018 ISS, and most of our earlier stage programs rely on ISS-based technology. Serious adverse safety data relating to either 1018 ISS or other ISS-based technology may require us to reduce the scope of or discontinue our operations.

      Our product candidates in clinical trials are based on 1018 ISS, and substantially all of our research and development programs use ISS-based technology. If any of our product candidates in clinical trials produce serious adverse safety data, we may be required to delay or discontinue all of our clinical trials. In addition, as all of our clinical product candidates contain 1018 ISS, potential collaborators may also be reluctant to establish collaborations for our products in distinct therapeutic areas due to the common safety risk across therapeutic areas. If adverse safety data are found to apply to our ISS-based technology as a whole, we may be required to discontinue our operations.

A key part of our business strategy is to establish collaborative relationships to commercialize and fund development of our product candidates. We may be unsuccessful in establishing and managing collaborative relationships, which may significantly limit our ability to develop and commercialize our products successfully, if at all.

      We will have to establish collaborative relationships to obtain domestic and international sales, marketing and distribution capabilities for our product candidates. We also intend to enter into collaborative relationships to provide funding to support our research and development programs. Currently we have established only one collaborative relationship, which is for our hepatitis B vaccine and hepatitis B therapeutic

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We rely on third parties to supply component materials necessary for our clinical product candidates and manufacture product candidates for our clinical trials. Loss of these suppliers or manufacturers, or failure to replace them may delay our clinical trials and research and development efforts and may result in additional costs, which would preclude us from producing our product candidates on commercially reasonable terms.

      We rely on contract relationships with third parties to obtain the component materials that are necessary for our clinical product candidates and to manufacture our product candidates for clinical trials. Termination or interruption of these relationships may occur due to circumstances that are outside our control, resulting in higher costs or delays in our product development efforts.

      In particular, we have relied on a single supplier to produce our ISS for clinical trials. ISS is a critical component of both of our AIC and hepatitis B vaccine product candidates. To date, we have manufactured only small quantities of ISS ourselves for research purposes. If we were unable to maintain or replace our existing source for ISS, we would have to establish an in-house ISS manufacturing capability, incurring increased capital and operating costs and potential delays in commercializing our product candidates. We or other third parties may not be able to produce ISS at a cost, quantity and quality that is available from our current third-party supplier.

      In addition, we do not currently have a contract manufacturer for AIC or enough AIC to supply ongoing clinical and, potentially, commercial needs. We believe that our existing supplies of AIC are only sufficient for us to conduct our currently planned Phase IIb clinical trial. We intend to qualify and enter into manufacturing agreements with one or more new commercial-scale contract manufacturers to produce additional supplies of AIC as required for completion of clinical trials and commercialization. If we are unable to complete such agreements, we would have to establish an internal commercial scale manufacturing capability for AIC, incurring increased capital and operating costs, delays in the commercial development of AIC and higher manufacturing costs than we have experienced to date.

We intend to contract with one or more third parties to conduct our planned Phase IIb and Phase III clinical trials for AIC and Phase III trials for our hepatitis B vaccine. If these third parties do not carry out their contractual obligations or meet expected deadlines, our planned clinical trials may be delayed and we may fail to obtain the regulatory approvals necessary to commercialize AIC or our hepatitis B vaccine.

      We are unable to independently conduct our planned clinical trials for AIC or our hepatitis B vaccine, and we intend to contract with third party contract research organizations to manage and conduct these trials. If these third parties do not carry out their contractual duties or obligations or meet expected deadlines, if the third parties need to be replaced or if the quality or accuracy of the clinical data they obtain is compromised due to failure to adhere to our clinical protocols or for other reasons, our planned clinical trials may be extended, delayed or terminated. Any extension, delay or termination of our trials would delay our ability to commercialize AIC or our hepatitis B vaccine and generate revenue.

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If any products we develop are not accepted by the market or if regulatory agencies limit our labeling indications or marketing claims, we may be unable to generate significant revenue, if any.

      We do not anticipate that any of our product candidates will be commercially available until 2007, if at all. Furthermore, even if we obtain regulatory approval for our product candidates and are able to successfully commercialize them, our product candidates may not gain market acceptance among physicians, patients, health care payors and the medical community. The FDA or other regulatory agencies could limit the labeling indication for which our product candidates may be marketed or could otherwise constrain our marketing claims, reducing our or our collaborators’ ability to market the benefits of our products to particular patient populations. If we are unable to successfully market any approved product candidates, or are limited in our marketing efforts by regulatory limits on labeling indications or marketing claims, our ability to generate revenues could be significantly impaired.

      In particular, treatment with AIC, if approved, will require a series of injections, and we expect that some of the patients that currently take oral or inhalable pharmaceutical products to treat their allergies would not consider our product. We believe that market acceptance of AIC will also depend on our ability to offer competitive pricing, increased efficacy and improved ease of use as compared to existing or potential new allergy treatments.

      We expect that Asia will be the primary target market for our hepatitis B vaccine, if approved. While we may seek partners for purposes of commercializing this product candidate in Asian and other non-U.S. markets in addition to or as a replacement for our current collaborative partner, which has an exclusive option to commercialize our hepatitis B vaccine and therapeutic product candidates, marketing challenges vary by market and could limit or delay acceptance in any particular country. We believe that market acceptance of our hepatitis B vaccine will depend on our ability to offer increased efficacy and improved ease of use as compared to existing or potential new hepatitis B vaccine products.

We face uncertainty related to coverage, pricing and reimbursement due to health care reform and heightened scrutiny from third party payors, which may make it difficult or impossible to sell our product candidates on commercially reasonable terms.

      In both domestic and foreign markets, our ability to generate revenues from the sales of any approved product candidates in excess of the costs of producing the product candidates will depend in part on the availability of reimbursement from third party payors. Existing laws affecting the pricing and coverage of pharmaceuticals and other medical products by government programs and other third party payors may change before any of our product candidates are approved for marketing. In addition, third party payors are increasingly challenging the price and cost-effectiveness of medical products and services. Significant uncertainty therefore exists as to coverage and reimbursement levels for newly approved health care products, including pharmaceuticals. Because we intend to offer products, if approved, that involve new technologies and new approaches to treating disease, the willingness of third party payors to reimburse for our products is particularly uncertain. We will have to charge a price for our products that is sufficiently high to enable us to recover the considerable capital resources we have spent and will continue to spend on product development. Adequate third-party reimbursement may not be available to enable us to maintain price levels sufficient to realize a return on our investment in product development. If it becomes apparent, due to changes in coverage or pricing of pharmaceuticals in our market or a lack of reimbursement, that it will be difficult, if not impossible, for us to generate revenue in excess of costs, we will need to alter our business strategy significantly. This could result in significant unanticipated costs, harm our future prospects and reduce our stock price.

Many of our competitors have greater financial resources and expertise than we do. If we are unable to successfully compete with existing or potential competitors despite these disadvantages we may be unable to generate revenue and our business will be harmed.

      We compete with many companies and institutions, including pharmaceutical companies, biotechnology companies, academic institutions and research organizations, in developing alternative therapies to treat or prevent allergy, infectious diseases, asthma and cancer, as well as those focusing more generally on the

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      AIC, if approved, will compete directly with conventional allergy shots and indirectly with antihistamines, steroid hormones called corticosteroids and anti-leukotrine agents, which block symptoms caused by inflammatory molecules, including those produced by GlaxoSmithKline Plc, Merck & Co., Inc. and AstraZeneca Plc. Since our AIC ragweed allergy treatment would require a series of injections, we expect that some of the patients that currently take oral or inhalable pharmaceutical products to treat their allergies would not consider our product.

      Our hepatitis B vaccine, if approved, will compete with existing three-shot vaccines produced by GlaxoSmithKline Plc and Merck & Co., Inc., among others, as well as potentially with a two-shot vaccine in clinical development by GlaxoSmithKline Plc.

      Existing and potential competitors may also compete with us for qualified scientific and management personnel, as well as for technology that would be advantageous to our business. If we are unable to compete with existing and potential competitors we may not be able to obtain financing, sell our product candidates or generate revenues.

We intend to develop, seek regulatory approval for and market our product candidates outside the U.S., requiring a significant commitment of resources. Failure to successfully manage our international operations could result in significant unanticipated costs and delays in regulatory approval or commercialization of our hepatitis B vaccine and therapeutic product candidates.

      We currently intend to conduct certain operations relating to our hepatitis B vaccine and therapeutic product candidates through Dynavax Asia Pte. Ltd., or Dynavax Asia, our subsidiary based in Singapore. We intend to commercialize our hepatitis B vaccine only outside the U.S. due to the presence of third-party patents in the U.S. covering hepatitis B surface antigen, a key component of our hepatitis B vaccine, that extend until as late as 2019. Developing, seeking regulatory approval for and marketing our product candidates outside the U.S. could impose substantial burdens on our resources and divert management’s attention from domestic operations. We may also conduct operations in other foreign jurisdictions.

      International operations are subject to risk, including:

	•	the difficulty of managing geographically distant operations, including recruiting and retaining qualified employees, locating adequate facilities and establishing useful business support relationships in the local community;
	•	compliance with varying international regulatory requirements;
	•	securing international distribution, marketing and sales capabilities;
	•	adequate protection of our intellectual property rights;
	•	difficulties and costs associated with complying with a wide variety of complex international laws and treaties;
	•	legal uncertainties and potential timing delays associated with tariffs, export licenses and other trade barriers;
	•	adverse tax consequences;
	•	the fluctuation of conversion rates between foreign currencies and the U.S. dollar; and
	•	geopolitical risks.

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      If we are unable to successfully manage our international operations, we may incur significant unanticipated costs and delays in regulatory approval or commercialization of our hepatitis B vaccine and therapeutic product candidates, as well as other product candidates that we may choose to commercialize internationally, which would impair our ability to generate revenue.

We use hazardous materials in our business. Any claims or liabilities relating to improper handling, storage or disposal of these materials could be time consuming and costly to resolve.

      Our research and product development involve the controlled storage, use and disposal of hazardous and radioactive materials and biological waste. We are subject to Federal, state and local laws and regulations governing the use, manufacture, storage, handling and disposal of these materials and certain waste products. We are currently in compliance with all government permits that are required for the storage, use and disposal of these materials. However, we cannot eliminate the risk of accidental contamination or injury to persons or property from these materials. In the event of an accident related to hazardous materials, we could be held liable for damages, cleanup costs or penalized with fines, and this liability could exceed the limits of our insurance policies and exhaust our internal resources. We may have to incur significant costs to comply with future environmental laws and regulations.

We face product liability exposure which, if not covered by insurance, could result in significant financial liability.

      While we have not experienced any product liability claims to date, the use of any of our product candidates in clinical trials and the sale of any approved products will subject us to potential product liability claims and may raise questions about a product’s safety and efficacy. As a result, we could experience a delay in our ability to commercialize one or more of our product candidates or reduced sales of any approved product candidates. In addition, a product liability claim may exceed the limits of our insurance policies and exhaust our internal resources. We have obtained limited product liability insurance coverage in the amount of $1 million for clinical trials with umbrella coverage of an additional $3 million. This coverage may not be adequate or may not continue to be available in sufficient amounts, at an acceptable cost or at all. We also may not be able to obtain commercially reasonable product liability insurance for any product approved for marketing in the future. A product liability claim, product recalls or other claims, as well as any claims for uninsured liabilities or in excess of insured liabilities, would divert our management’s attention from our business and could result in significant financial liability.

Risks Related to Our Intellectual Property and Intellectual Property Litigation

If the combination of patents, trade secrets and contractual provisions that we rely on to protect our intellectual property is inadequate, the value of our product candidates will decrease.

      Our success depends on our ability to:

	•	obtain and protect commercially valuable patents or the rights to patents both domestically and abroad;
	•	operate without infringing upon the proprietary rights of others; and
	•	prevent others from successfully challenging or infringing our proprietary rights.

      We will be able to protect our proprietary rights from unauthorized use only to the extent that these rights are covered by valid and enforceable patents or are effectively maintained as trade secrets. We try to protect our proprietary rights by filing and prosecuting U.S. and foreign patent applications. Legal standards relating to the validity and scope of patent claims in the biopharmaceutical field can be highly uncertain, are still evolving and involve complex legal and factual questions for which important legal principles remain unresolved. The biopharmaceutical patent environment outside the U.S. is even more uncertain. We may be particularly affected by this for products with significant markets outside the U.S. For example, we expect to market our hepatitis B vaccine, if approved, in foreign countries with high incidences of hepatitis B,

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	•	we might not have been the first to make the inventions covered by each of our pending patent applications and issued patents;
	•	we might not have been the first to file patent applications for these inventions;
	•	the pending patent applications we have filed or to which we have exclusive rights may not result in issued patents or may take longer than we expect to result in issued patents;
	•	the claims of any patents that are issued may not provide meaningful protection;
	•	our issued patents may not provide a basis for commercially viable products or may not be valid or enforceable;
	•	we might not be able to develop additional proprietary technologies that are patentable;
	•	the patents licensed or issued to us or our collaborators may not provide a competitive advantage;
	•	patents issued to other companies, universities or research institutions may harm our ability to do business;
	•	other companies, universities or research institutions may independently develop similar or alternative technologies or duplicate our technologies and commercialize discoveries that we attempt to patent; and
	•	other companies, universities or research institutions may design around technologies we have licensed, patented or developed.

      We also rely on trade secret protection and confidentiality agreements to protect our interests in proprietary know-how that is not patentable and for processes for which patents are difficult to enforce. We cannot be certain that we will be able to protect our trade secrets adequately. Any leak of confidential data into the public domain or to third parties could allow our competitors to learn our trade secrets. If we are unable to adequately obtain or enforce proprietary rights we may be unable to commercialize our products, enter into collaborations, generate revenue or maintain any advantage we may have with respect to existing or potential competitors.

If third parties successfully assert that we have infringed their patents and proprietary rights or challenge the validity of our patents and proprietary rights, we may become involved in intellectual property disputes and litigation that would be costly, time consuming, and delay or prevent development of our product candidates.

      We may be exposed to future litigation by third parties based on claims that our product candidates, proprietary technologies or the licenses on which we rely, infringe their intellectual property rights, or we may be required to enter into litigation to enforce patents issued or licensed to us or to determine the scope or validity of another party s proprietary rights. If we become involved in any litigation, interference or other administrative proceedings related to our intellectual property or the intellectual property of others, we will incur substantial expenses and it will divert the efforts of our technical and management personnel. Others may succeed in challenging the validity of our issued and pending claims. If we are unsuccessful in defending or prosecuting any such claim we could be required to pay substantial damages and we may be unable to commercialize our product candidates or use these proprietary technologies unless we obtain a license from the third party. A license may require us to pay substantial royalties, require us to grant a cross-license to our technology or may not be available to us on acceptable terms. In addition, we may be required to redesign our technology so it does not infringe a third party s patents, which may not be possible or could require substantial funds and time. Any of these outcomes may require us to change our business strategy and could reduce the value of our business.

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      In particular, one of our potential competitors, Coley Pharmaceutical Group, or Coley, has issued U.S. patent claims, as well as patent claims pending with the U.S. Patent and Trademark Office, that, if held to be valid, could require us to obtain a license in order to commercialize one or more of our formulations of ISS in the U.S., including AIC. On December 17, 2003, the United States Patent and Trademark Office declared an interference to resolve first-to-invent disputes between a patent application filed by the Regents of the University of California, which is exclusively licensed to us, and an issued U.S. patent owned by Coley relating to immunostimulatory DNA sequences. The declaration of interference names the Regents of the University of California as senior party, indicating that a patent application filed by the Regents of the University of California and licensed to us was filed prior to a patent application owned by Coley that led to an issued U.S. patent. The interference provides the first forum to challenge the validity and priority of certain of Coley’s patents. If successful, the interference action would establish our founders as the inventors of the inventions in dispute. If we do not prevail in the interference proceeding, we may not be able to obtain patent protection on the subject matter of the interference, which would have a material adverse impact on our business. In addition, if Coley prevails in the interference, it may seek to enforce its rights under issued claims, including, for example, by suing us for patent infringement. Consequently, we may need to obtain a license to issued and/or pending claims held by Coley by paying cash, granting royalties on sales of our products or offering rights to our own proprietary technologies. Such a license may not be available to us on acceptable terms, if at all.

We rely on our licenses from the Regents of the University of California. Impairment of these licenses or our inability to maintain them would severely harm our business.

      Our success depends upon our license arrangements with the Regents of the University of California. These licenses are critical to our research and product development efforts. Our dependence on these licenses subjects us to numerous risks, such as disputes regarding the invention and corresponding ownership rights in inventions and know-how resulting from the joint creation or use of intellectual property by us and the Regents of the University of California, or scientific collaborators. Additionally, our agreements with the Regents of the University of California generally contain diligence or milestone-based termination provisions. Our failure to meet any obligations pursuant to these provisions could allow the Regents of the University of California to terminate any of these licensing agreements or convert them to non-exclusive licenses. In addition, our license agreements with the Regents of the University of California may be terminated or may expire by their terms, and we may not be able to maintain the exclusivity of these licenses. If we cannot maintain licenses that are advantageous or necessary to the development or the commercialization of our product candidates, we may be required to expend significant time and resources to develop or license similar technology.

Risks Related to Our Common Stock and this Offering

We expect that our stock price will be volatile, and your investment may suffer a decline in value.

      There is currently no public market for our common stock. The initial public offering price of our stock will be determined through negotiations between us and representatives of the underwriters, and may not reflect the price that will prevail in the open market. You may not be able to resell your shares at or above the initial public offering price. The market prices for securities of biopharmaceutical companies have in the past been, and are likely to continue in the future to be, very volatile. The market price of our common stock may be subject to substantial volatility depending upon many factors, many of which are beyond our control, including:

	•	progress or results of any of our clinical trials, in particular any announcements regarding the progress or results of our planned Phase III trials for AIC and our hepatitis B vaccine;
	•	progress of regulatory approval of our product candidates, in particular AIC and our hepatitis B vaccine, and compliance with ongoing regulatory requirements;

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	•	our ability to establish collaborations for the development and commercialization of our product candidates;
	•	market acceptance of our product candidates;
	•	our ability to raise additional capital to fund our operations;
	•	technological innovations, new commercial products or drug discovery efforts and preclinical and clinical activities by us or our competitors;
	•	changes in our intellectual property portfolio or developments or disputes concerning the proprietary rights of our products or product candidates;
	•	our ability to obtain component materials and successfully enter into manufacturing relationships for our product candidates or establish manufacturing capacity on our own;
	•	maintenance of our existing licensing agreements with the Regents of the University of California;
	•	changes in government regulations;
	•	issuance of new or changed securities analysts reports or recommendations;
	•	general economic conditions and other external factors;
	•	actual or anticipated fluctuations in our quarterly financial and operating results; and
	•	degree of trading liquidity in our common stock.

      One or more of these factors could cause a decline in the price of our common stock in the public market. In addition, securities class action litigation has often been brought against a company following a decline in the market price of its securities. We may in the future be the target of similar litigation. Securities litigation could result in substantial costs, divert management’s attention and resources and disrupt our business operations.

If the ownership of our common stock continues to be highly concentrated, it may prevent you and other stockholders from influencing significant corporate decisions and may result in conflicts of interest that could cause our stock price to decline.

      Our executive officers, directors and their affiliates beneficially own or control approximately 29.5% of our outstanding common stock as of September 30, 2003 (after giving effect to the conversion of all outstanding shares of our preferred stock and assuming the exchange of 15,200,000 shares of ordinary stock of our subsidiary, Dynavax Asia Pte. Ltd., issued in October 2003, into 2,111,111 shares of our common stock upon the completion of this offering, but assuming no exercise of the underwriters’ over-allotment option and no exercise of outstanding options or warrants), and will beneficially own 22.0% of our outstanding common stock after this offering (21.2% if the underwriters exercise in full their over-allotment option). Accordingly, these executive officers, directors and their affiliates, acting as a group, will have substantial influence over the outcome of corporate actions requiring stockholder approval, including the election of directors, any merger, consolidation or sale of all or substantially all of our assets or any other significant corporate transactions. These stockholders may also delay or prevent a change of control of us, even if such a change of control would benefit our other stockholders. The significant concentration of stock ownership may adversely affect the trading price of our common stock due to investors perception that conflicts of interest may exist or arise. See Management and Principal Stockholders for details on our capital stock ownership.

Anti-takeover provisions of our certificate of incorporation, bylaws and Delaware law may prevent or frustrate a change in control, even if an acquisition would be beneficial to our stockholders, which could affect our stock price adversely and prevent attempts by our stockholders to replace or remove our current management.

      Provisions of our certificate of incorporation and bylaws may delay or prevent a change in control, discourage bids at a premium over the market price of our common stock and adversely affect the market

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	•	authorizing our Board of Directors to issue additional preferred stock with voting rights to be determined by the Board of Directors;
	•	limiting the persons who can call special meetings of stockholders;
	•	prohibiting stockholder actions by written consent;
	•	creating a classified board of directors pursuant to which our directors are elected for staggered three-year terms;
	•	providing that a supermajority vote of our stockholders is required for amendment to certain provisions of our certificate of incorporation and bylaws; and
	•	establishing advance notice requirements for nominations for election to our Board of Directors or for proposing matters that can be acted on by stockholders at stockholder meetings.

      In addition, we are subject to the provisions of the Delaware corporation law that, in general, prohibit any business combination with a beneficial owner of 15% or more of our common stock for five years unless the holder’s acquisition of our stock was approved in advance by our board of directors.

If you purchase our common stock in this offering, you will incur immediate and substantial dilution in the book value of your shares.

      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 pay a price per share that substantially exceeds the book value of our assets after subtracting our liabilities. Further, investors purchasing common stock in this offering will contribute approximately 43% of the total amount invested by stockholders since our inception to September 30, 2003, but will only own approximately 25% of the shares of common stock outstanding.

      This dilution is due to our investors who purchased shares prior to this offering having paid substantially less per share when they purchased their shares than the price offered to the public in this offering and the exercise of stock options granted to our employees. As a result of this dilution, investors purchasing stock in this offering may receive significantly less than the purchase price paid in this offering in the event of a liquidation. For more information, please refer to the section of this prospectus entitled Dilution.

Future sales of our common or preferred stock may lower the market price of our common stock.

      After this offering, we will have outstanding 23,673,756 shares of common stock, based upon 17,673,756 shares of common stock outstanding as of September 30, 2003, which assumes the exchange of 15,200,000 shares of ordinary stock of our subsidiary, Dynavax Asia Pte Ltd., issued in October 2003 into 2,111,111 shares of our common stock upon the completion of this offering and the conversion of all convertible preferred stock into common, but assumes no exercise of the underwriters’ over-allotment option and no exercise of outstanding options or warrants. This includes the 6,000,000 shares we are selling in this offering, which may be resold in the public market immediately. The remaining 74.7%, or 17,673,756 shares, of our total outstanding shares will become available for resale in the public market as shown in the chart below. As restrictions on resale end, the market price could drop significantly if the holders of these restricted shares sell them or are perceived by the market as intending to sell them.

      For a more detailed description, please see “Shares Eligible for Future Sale,” on page 69.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA

      This prospectus contains forward-looking statements that are subject to a number of risks and uncertainties, many of which are beyond our control. These forward-looking statements include statements about our:

	•	business strategy;
	•	uncertainty regarding our future operating results;
	•	anticipated sources of funds, including the proceeds from this offering, to fund our operations for the 24 months following the date of this prospectus; and
	•	plans, objectives, expectations and intentions contained in this prospectus that are not historical facts.

      All statements, other than statements of historical facts included in this prospectus, regarding our strategy, future operations, financial position, estimated revenues or losses, projected costs, prospects, plans and objectives of management are forward-looking statements. When used in this prospectus, the words “will,” “may,” “believe,” “anticipate,” “intend,” “estimate,” “expect,” “project” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. All forward-looking statements speak only as of the date of this prospectus. You should not place undue reliance on these forward-looking statements. Although we believe that our plans, intentions and expectations reflected in or suggested by the forward-looking statements we make in this prospectus are reasonable, we may be unable to achieve these plans, intentions or expectations. We disclose important factors that could cause our actual results to differ materially from our expectations under “Risk Factors” and elsewhere in this prospectus. These cautionary statements qualify all forward-looking statements attributable to us or persons acting on our behalf.

      Information regarding market and industry statistics contained in the “Prospectus Summary” and “Business” sections of this prospectus is included based on information available to us that we believe is accurate. It is generally based on academic and other publications that are not produced for purposes of securities offerings or economic analysis.

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

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USE OF PROCEEDS

      We estimate that we will receive net proceeds of approximately $70,998,000 from the sale of the shares of common stock in this offering, based on an assumed initial public offering price of $13.00 per share and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us. If the underwriters’ over-allotment option is exercised in full, our net proceeds will be approximately $81,879,000. We currently intend to use the net proceeds of this offering for the continued development of our clinical and preclinical stage programs and general corporate purposes.

      Upon completion of this offering, we will make a one time cash payment to the University of California of approximately $217,000, based on an assumed initial public offering price of $13.00 per share. As of the date of this prospectus, we have not allocated any other proceeds for specific purposes. We may also use a portion of the net proceeds of this offering to enter into strategic collaborations with third parties. From time to time, in the ordinary course of business, we expect to evaluate potential strategic collaborations. At this time, however, we do not have any present understandings, commitments or agreements with respect to any material strategic collaborations.

      The amounts and timing of our actual use of proceeds will depend upon numerous factors, including the status of our product development and commercialization efforts, technological advances, the amount of proceeds actually raised in this offering and the amount of cash provided by any potential collaborations. As a result, we cannot specify with certainty the amounts that we may allocate to the particular uses of the net proceeds of this offering. Our management will have significant flexibility and discretion in applying the net proceeds of this offering. Pending any use, we will invest the net proceeds of this offering generally in short-term, investment grade, interest bearing securities but cannot predict that these investments will yield a favorable return.

DIVIDEND POLICY

      We have never declared or paid any cash dividends on shares of our common stock. We currently intend to retain any future earnings for future growth and do not anticipate paying any cash dividends in the foreseeable future.

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CAPITALIZATION

      The following table sets forth our unaudited cash, cash equivalents and marketable securities and our capitalization as of September 30, 2003:

	•	on an actual basis;
	•	on a pro forma basis to give effect to the filing of an amended and restated certificate of incorporation in October 2003 and the sale of 15,200,000 ordinary shares of our subsidiary Dynavax Asia Pte. Ltd. issued in a private financing in October 2003 for gross proceeds of $15.2 million which will be reflected as a minority interest liability until conversion into our preferred or common stock; and
	•	on a pro forma basis as adjusted to give effect to (1) the filing of an amended and restated certificate of incorporation to provide for authorized capital stock of 100,000,000 shares of common stock and 5,000,000 shares of preferred stock, (2) the sale by us of 6,000,000 shares of common stock at an assumed initial public offering price of $13.00 per share in this offering and the receipt of the estimated net proceeds therefrom, after deducting underwriting discounts and commissions, estimated offering expenses payable by us and a one-time cash payment to the University of California of approximately $217,000, (3) the conversion of all preferred stock into common stock upon the completion of this offering, and (4) the exchange of 15,200,000 ordinary shares of Dynavax Asia Pte. Ltd. for 2,111,111 shares of our common stock upon the completion of this offering.

      You should read the information in this table together with “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and our consolidated financial statements and accompanying notes appearing elsewhere in this prospectus.

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DILUTION

      Our net tangible book value as of September 30, 2003 was approximately $(68,042,000), or approximately $(36.76) per share of common stock. Net tangible book value per share represents total tangible assets less total liabilities, divided by the number of shares of common stock outstanding. Our pro forma net tangible book value reflects the issuance and exchange of 15,200,000 shares of ordinary stock of our subsidiary, Dynavax Asia Pte. Ltd., issued in October 2003 for gross proceeds of $15.2 million, into 2,111,111 shares of our common stock upon the completion of this offering, and assuming the conversion of all shares of preferred stock outstanding as of September 30, 2003 into common stock. Dilution in pro forma net tangible book value per share represents the difference between the amount per share paid by purchasers of common stock in this offering and the pro forma net tangible book value per share of our common stock immediately after the offering. After giving effect to our sale of shares of common stock in this offering at an assumed initial public offering price of $13.00 per share and after deduction of the underwriting discounts and commissions and estimated offering expenses payable by us, our pro forma net tangible book value as of September 30, 2003 would have been approximately $101,575,000, or $4.30 per share. This represents an immediate increase in pro forma net tangible book value of $2.56 per share to existing stockholders and an immediate dilution in pro forma net tangible book value of $8.70 per share to purchasers of common stock in this offering.

      The following table sets forth on a pro forma basis as of September 30, 2003, the total number of shares of common stock purchased from us, the total consideration paid for these shares and the average price per share paid by our existing stockholders and by new investors, before deducting underwriting discounts and commissions and estimated offering expenses payable by us at an assumed initial public offering price of $13.00 per share.

      This table assumes that no options or warrants were exercised after September 30, 2003. As of September 30, 2003, there were outstanding options to purchase a total of 911,695 shares of common stock at a weighted average exercise price of approximately $2.13 per share and warrant exercisable for 253,233 shares of Series D Preferred Stock, which will convert into a warrant exercisable for 84,411 shares of common stock issuable at the exercise price of $6.18 per share upon the completion of this offering.

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SELECTED CONSOLIDATED FINANCIAL DATA

      You should read the following selected consolidated financial data in conjunction with our consolidated financial statements and the related notes and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included elsewhere in this prospectus. The consolidated statements of operations data for the years ended December 31, 2000, 2001, and 2002 and the consolidated balance sheet data as of December 31, 2001 and 2002 are derived from the audited consolidated financial statements that are included elsewhere in this prospectus. The statements of operations data for the years ended December 31, 1998 and 1999 and the balance sheet data as of December 31, 1998, 1999 and 2000 are derived from our audited consolidated financial statements not included in this prospectus. The consolidated statements of operations data for the nine months ended September 30, 2002 and 2003 and the balance sheet data as of September 30, 2003 are derived from our unaudited interim consolidated financial statements that are included elsewhere in this prospectus. The unaudited interim consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s consolidated financial position as of September 30, 2003 and consolidated results of operations for the nine months ended September 30, 2002 and 2003. Historical results are not necessarily indicative of the results of operations to be expected for future periods. See Note 3 of “Notes to Consolidated Financial Statements” for a description of the method that we used to compute our historical and pro forma basic and diluted net loss per share attributable to common stockholders.

(1)	See Note 3 to our Notes to Consolidated Financial Statements for a description of pro forma net loss per share attributable to common stockholders.

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*	Includes non-cash charges for stock-based compensation expense as follows (in thousands):