RISK FACTORS

Any investment in our common stock involves a high degree of risk. Investors should carefully consider the risks described below and all of the information contained in this prospectus before deciding whether to purchase our common stock and warrants. Our business, financial condition or results of operations could be materially adversely affected by these risks if any of them actually occur. This prospectus also contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks we face as described below and elsewhere in this prospectus.

Risks Related to our Business

We will need to raise substantial funds, on an ongoing basis, for general corporate purposes and operations, including our clinical trials. Such funding may not be available or may not be available on attractive terms.

As of September 30, 2012, we had approximately $0.1 million of cash on hand. We will need substantial additional funding, on an ongoing basis, in order to continue execution of our clinical trials, to move our product candidates towards commercialization, to continue prosecution and maintenance of our large patent portfolio, to continue development and optimization of our manufacturing and distribution arrangements, and for other corporate purposes. Any financing, if available, may include restrictive covenants and provisions that could limit our ability to take certain actions, preference provisions for the investors, and/or discounts, warrants or other incentives. Any financing will involve issuance of equity and/or debt, and such issuances will be dilutive to existing shareholders. There can be no assurance that we will be able to complete any of the financings, or that the terms for such financings will be attractive. If we are unable to obtain additional funds on a timely basis or on acceptable terms, we may be required to curtail or cease some or all of our operations at any time.

As of November 28, 2012, we have executed agreements to retire $34,472,930 aggregate amount of convertible notes, notes and payables by entering into Conversion Agreements with our non-affiliated and affiliated note holders and creditors, including certain of our directors and executive officers. This aggregate debt amount will be converted into 9,199,998 common shares and warrants exercisable for 4,599,994 shares of common stock, effective upon the closing of this public offering. The warrants will have an exercise period of five years from the date of issuance and an exercise price of $6.40 per share. Approximately $4.7 million aggregate principal amount of convertible notes and notes will be outstanding after the offering. Of such amount, approximately $0.88 million aggregate principal amount of our convertible notes and notes are past due. We intend to enter into agreements after this offering to convert a portion of the convertible notes and notes into common stock and warrants. There can be no assurance that we will be able to enter into such agreements or that the terms of such agreements will be on acceptable terms.

We are likely to continue to incur substantial losses, and may never achieve profitability.

We have incurred net losses every year since our formation in March 1996, and had a deficit accumulated during the development stage of approximately $251.8 million and $288.6 million as of December 31, 2011 and September 30, 2012, respectively, of which $117.2 million was cash expenditures and $134.6 million was non-cash accounting measures as of December 31, 2011 and $131.7 million was cash expenditures and $156.9 million was non-cash accounting measures as of September 30, 2012. We expect that these losses will continue, and we anticipate negative cash flows from operations for the foreseeable future. We may never achieve or sustain profitability.

Our auditors have issued a “going concern” audit opinion.

Our independent auditors have indicated, in their report on our December 31, 2011 financial statements, that there is substantial doubt about our ability to continue as a going concern. A “going concern” opinion indicates that the financial statements have been prepared assuming we will continue as a going concern and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets, or the amounts and classification of liabilities, that may result if we do not continue as a going concern. Therefore, you should not rely on our consolidated balance sheet as an indication of the amount of proceeds that would be available to satisfy claims of creditors, and potentially be available for distribution to shareholders, in the event of liquidation.

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As a development stage company with a novel technology and unproven business strategy, our limited history of operations makes an evaluation of our business and prospects difficult.

We have had a limited operating history and we are still in the process of developing our product candidates through clinical trials. Our technology is novel and involves mobilizing the immune system to fight a patient’s cancer. Immune therapies have been pursued by many parties for decades, and have experienced many failures. In addition, our technology involves personalized treatment products, a new approach to medical products that involves new product economics and business strategies, which have not yet been shown to be commercially feasible or successful. We have not yet gone through scale-up of our operations to commercial scale. This limited operating history, along with the novelty of our technology, product economics, and business strategy, and the limited scale of our operations to date, makes it difficult to assess our prospects for generating revenues commercially in the future.

We will need to expand our management and technical personnel as our operations progress, and we may not be able to recruit such additional personnel and/or retain existing personnel.

As of November 28, 2012, we employ eight (8) full-time employees. The rest of our personnel are retained on a consulting or contractor basis. Biotech companies would typically have a larger number of employees by the time they reach late stage clinical trials. Such trials require extensive management activities and skill sets, including scientific, medical, regulatory (for FDA and foreign regulatory counterparts), manufacturing, distribution and logistics, site management, business, financial, legal, public relations outreach to both the patient community and physician community, intellectual property, administrative, regulatory (SEC), investor relations and other.

In order to fully perform all these diverse functions, with late stage trials under way at many sites across the U.S. and soon in Europe, we will need to expand our management and technical personnel. However, the pool of such personnel with expertise and experience with living cell products, such as our DCVax immune cell product, is very limited. In addition, we are a small company with limited resources, our business prospects are uncertain and our stock price is volatile. For some or all of such reasons, we may not be able to recruit all the management and technical personnel we need, and/or we may not be able to retain all of our existing personnel. In such event, we may have to continue our operations with a smaller than usual team of personnel, and our business and financial results may suffer.

We rely at present on third-party contract manufacturers. As a result, we may be at risk for capacity limitations and/or supply disruptions.

We currently rely upon Cognate BioServices, Inc., or Cognate, to produce all of our DCVax product in the U.S., and to supervise the production of our DCVax product candidates outside the U.S. The majority owner of Cognate is Toucan Capital, one of our major stockholders, and its affiliates. We have an agreement in place with Cognate pursuant to which Cognate has agreed to provide manufacturing and other services for the next five years, in connection with our Phase III clinical trial of DCVax -L in brain cancer, and other programs. The agreement requires us to make certain minimum monthly payments to Cognate in order to have dedicated manufacturing capacity available for our products, irrespective of whether we actually order any DCVax products. The agreement also specifies the amounts we must pay for Cognate's actual manufacturing of DCVax for patients.

We have entered into an agreement with King’s College London to manufacture DCVax for our clinical trial and our compassionate use cases. Cognate will manage and supervise the processing in London. In addition, our partner, Fraunhofer, has received approval and certification from the regional and national regulatory agencies in Germany for the manufacture of DCVax for GBM. We anticipate that the manufacturing facilities in the U.K. and Germany will be able to supply DCVax products for anywhere in Europe (and to the U.S., if needed), however this may not turn out to be feasible, for regulatory, operational and/or logistical reasons.

Problems with the manufacturing facilities or processes of Cognate or our partners in the U.K. and/or Germany could result in a failure to produce, or a delay in production, of adequate supplies of our DCVax product candidates. A number of factors could cause interruptions or delays, including the inability of a supplier to provide raw materials, equipment malfunctions or failures, damage to a facility due to natural

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disasters or otherwise, changes in FDA regulatory requirements or standards that require modifications to our manufacturing processes, action by the FDA or European regulators, or by us that results in the halting or slowdown of production of components or finished products due to regulatory issues, our manufacturers going out of business or failing to produce product as contractually required, and/or other similar factors. Because manufacturing processes for our DCVax product candidates are highly complex, require specialized facilities and personnel that are not widely available in the industry, involve equipment and training with long lead times, and are subject to lengthy regulatory approval processes, alternative qualified production capacity may not be available on a timely basis or at all. Difficulties, delays or interruptions in the manufacturing and supply of our DCVax product candidates could require us to stop enrolling additional new patients into our trial, and/or require us to stop the trial or other program, increase our costs, damage our reputation and, if our product candidates are approved for sale, cause us to lose revenue or market share if our manufacturers are unable to timely meet market demands.

The manufacturing of our product candidates will have to be greatly scaled up for commercialization, and neither we nor other parties in the industry have experience with such scale-up.

As is the case with any clinical trial, our Phase III clinical trial of DCVax-L for GBM involves a number of patients that is a small fraction of the number of potential patients for whom DCVax-L may be applicable in the commercial market. The same will be true of our other clinical programs with our other DCVax product candidates. If our DCVax-L, and/or other DCVax product candidates, are approved for commercial sale, it will be necessary to greatly scale up the volume of manufacturing, far above its level for the trials. Neither we nor our contract manufacturers have experience with such scale-up. In addition, there are virtually no consultants or advisors in the industry who have such experience and can provide guidance or assistance, because active immune therapies such as DCVax are a fundamentally new category of product in two major ways: these active immune therapy products consist of living cells, not chemical or biologic compounds, and the products are personalized. To our knowledge, no such products have successfully completed the necessary scale-up for commercialization without material difficulties. For example, Dendreon has encountered substantial difficulties trying to scale up the manufacturing of its Provenge product for commercialization.

The necessary specialized facilities, equipment and personnel may not be available or obtainable for the scale-up of manufacturing of our product candidates.

The manufacture of living cells requires specialized facilities, equipment and personnel which are entirely different than what is required for manufacturing of chemical or biologic compounds. Scaling up the manufacturing of living cell products to volume levels required for commercialization will require enormous amounts of these specialized facilities, equipment and personnel — especially where, as in the case of our DCVax product candidates, the product is personalized and must be made for each patient individually. Since living cell products are so new, and have barely begun to reach commercialization, the supply of the specialized facilities, equipment and personnel needed for them has not yet developed. It may not be possible for us or our manufacturers to obtain all of the specialized facilities, equipment and personnel needed for commercialization of our DCVax product candidates. This could delay or halt our commercialization.

Our technology is novel, involves complex immune system elements, and may not prove to be effective.

Data already obtained, or in the future obtained, from pre-clinical studies and clinical trials do not necessarily predict the results that will be obtained from later pre-clinical studies and clinical trials. Over the course of several decades, there have been many different immune therapy product designs — and many product failures and company failures. To our knowledge, to date, only one active immune therapy, Provenge, has been approved by the FDA. The human immune system is complex, with many diverse elements, and the state of scientific understanding of the immune system is still limited. Some immune therapies previously developed by other parties showed surprising and unexpected toxicity in clinical trials. Other immune therapies developed by other parties delivered promising results in early clinical trials, but failed in later stage clinical trials. To date, we have only completed early stage trials in limited numbers of patients. Although the results of those trials were quite positive, those results may not be achieved in our later stage clinical trials, such as the 300-patient Phase III trial we are now conducting for GBM, and our product candidates may not ultimately be found to be effective.

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Clinical trials for our product candidates are expensive and time consuming, and their outcome is uncertain.

The process of obtaining and maintaining regulatory approvals for new therapeutic products is expensive, lengthy and uncertain. Costs and timing of clinical trials may vary significantly over the life of a project owing to any or all of the following non-exclusive reasons:

Late stage clinical trials, such as our Phase III clinical trial for GBM patients, are especially expensive, typically requiring tens of millions of dollars, and take years to reach their outcomes. Such outcomes often fail to reproduce the results of earlier trials. It is often necessary to conduct multiple late stage trials (including multiple Phase III trials) in order to obtain sufficient results to support product approval, which further increases the expense. Sometimes trials are further complicated by changes in requirements while the trials are under way (for example, when the standard of care changes for the disease that is being studied in the trial). Accordingly, any of our current or future product candidates could take a significantly longer time to gain regulatory approval than we expect, or may never gain approval, either of which could delay or stop the commercialization of our DCVax product candidates.

We may be required to suspend or discontinue clinical trials due to unexpected side effects or other safety risks that could preclude approval of our product candidates.

Our clinical trials may be suspended at any time for a number of reasons. For example, we may voluntarily suspend or terminate our clinical trials if at any time we believe that they present an unacceptable risk to the clinical trial patients. In addition, the FDA or other regulatory agencies may order the temporary or permanent discontinuation of our clinical trials at any time if they believe that the clinical trials are not being conducted in accordance with applicable regulatory requirements or that they present an unacceptable safety risk to the clinical trial patients.

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Administering any product candidate to humans may produce undesirable side effects. These side effects could interrupt, delay or halt clinical trials of our product candidates and could result in the FDA or other regulatory authorities denying further development or approval of our product candidates for any or all targeted indications. Ultimately, some or all of our product candidates may prove to be unsafe for human use. Moreover, we could be subject to significant liability if any volunteer or patient suffers, or appears to suffer, adverse health effects as a result of participating in our clinical trials.

We have limited experience in conducting and managing clinical trials.

We rely on third parties to assist us, on a contract services basis, in managing and monitoring all of our clinical trials. We do not have experience conducting late stage clinical trials ourselves without third party service firms, other than our current Phase III trial, nor do we have experience in supervising such third parties in managing late stage, multi-hundred patient clinical trials, other than our current Phase III trial. Our lack of experience and/or our reliance on these third party service firms may result in delays or failure to complete these trials successfully and on time. If the third parties fail to perform, we may not be able to find sufficient alternative suppliers of those services in a reasonable time period, or on commercially reasonable terms, if at all. If we were unable to obtain alternative suppliers of such services, we might be forced to delay, suspend or stop our 300-patient Phase III clinical trial of DCVax-L for GBM.

Multiple late stage clinical trials of DCVax-L for GBM, our lead product, may be required before we can obtain regulatory approval.

Typically, companies conduct multiple late stage clinical trials of their product candidates before seeking product approval. Our current Phase III 300-patient clinical trial of DCVax-L for GBM is our first late stage trial. We may be required to conduct additional late stage trials with DCVax-L for GBM before we can obtain product approval. This would substantially delay our commercialization. There is also some possibility that changes requested by the FDA could complicate the application process for product approval. In addition, a number of products are under development for brain cancer and at least one has recently been approved in the U.S.. It is possible that the standard of care for brain cancer could change while our Phase III trial is still under way. This could necessitate further clinical trials with our DCVax-L product candidate for brain cancer.

Changes in manufacturing methods for DCVax-L could require us to conduct equivalency studies and/or additional clinical trials.

With biologics products, “the process is the product”: i.e., the manufacturing process is considered to be as integral to the product as is the composition of the product itself. If any changes are made in the manufacturing process, and such changes are considered material by the regulatory authorities, the company sponsor may be required to conduct equivalency studies to show that the product is equivalent under the changed manufacturing processes as under the original manufacturing processes, and/or the company sponsor may be required to conduct additional clinical trials. Our manufacturing processes have undergone some changes during the early clinical trials. Accordingly, we may be required to conduct equivalency studies, and/or additional clinical trials, before we can obtain product approval, unless the regulatory authorities are satisfied that the changes in processes do not affect the quality, efficacy or safety of the product.

We may not receive regulatory approvals for our product candidates or there may be a delay in obtaining such approvals.

Our products and our ongoing development activities are subject to regulation by regulatory authorities in the countries in which we or our collaborators and distributors wish to test, manufacture or market our products. For instance, the FDA will regulate the product in the U.S. and equivalent authorities, such as the European Medicines Agency, or EMA, will regulate in Europe. Regulatory approval by these authorities will be subject to the evaluation of data relating to the quality, efficacy and safety of the product for its proposed use, and there can be no assurance that the regulatory authorities will find our data sufficient to support product approval of DCVax-L .

The time required to obtain regulatory approval varies between countries. In the U.S., for products without “Fast Track” status, it can take up to eighteen (18) months after submission of an application for product approval to receive the FDA's decision. Even with Fast Track status, FDA review and decision can

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take up to twelve (12) months. At present, we do not have Fast Track status for our lead product, DCVax-L for GBM. We plan to apply for Fast Track status, but there can be no assurance that FDA will grant us such status for DCVax-L.

Different regulators may impose their own requirements and may refuse to grant, or may require additional data before granting, an approval, notwithstanding that regulatory approval may have been granted by other regulators. Regulatory approval may be delayed, limited or denied for a number of reasons, including insufficient clinical data, the product not meeting safety or efficacy requirements or any relevant manufacturing processes or facilities not meeting applicable requirements as well as case load at the regulatory agency at the time.

We may fail to comply with regulatory requirements.

Our success will be dependent upon our ability, and our collaborative partners’ abilities, to maintain compliance with regulatory requirements, including current good manufacturing practices, or cGMP, and safety reporting obligations. The failure to comply with applicable regulatory requirements can result in, among other things, fines, injunctions, civil penalties, total or partial suspension of regulatory approvals, refusal to approve pending applications, recalls or seizures of products, operating and production restrictions and criminal prosecutions.

Regulatory approval of our product candidates may be withdrawn at any time.

After regulatory approval has been obtained for medicinal products, the product and the manufacturer are subject to continual review, including the review of adverse experiences and clinical results that are reported after our products are made available to patients, and there can be no assurance that such approval will not be withdrawn or restricted. Regulators may also subject approvals to restrictions or conditions, or impose post-approval obligations on the holders of these approvals, and the regulatory status of such products may be jeopardized if such obligations are not fulfilled. If post-approval studies are required, such studies may involve significant time and expense.

The manufacturer and manufacturing facilities we use to make any of our products will also be subject to periodic review and inspection by the FDA or EMA, as applicable. The discovery of any new or previously unknown problems with the product, manufacturer or facility may result in restrictions on the product or manufacturer or facility, including withdrawal of the product from the market. We will continue to be subject to the FDA or EMA requirements, as applicable, governing the labeling, packaging, storage, advertising, promotion, recordkeeping, and submission of safety and other post-market information for all of our product candidates, even those that the FDA or EMA, as applicable, had approved. If we fail to comply with applicable continuing regulatory requirements, we may be subject to fines, suspension or withdrawal of regulatory approval, product recalls and seizures, operating restrictions and other adverse consequences.

Our product candidates will require a different distribution model than conventional therapeutic products, and this may impede commercialization of our product candidates.

Our DCVax product candidates consist of living human immune cells. Such products are entirely different from chemical or biologic drugs, and require different handling, distribution and delivery than chemical or biologic drugs. One crucial difference is that our DCVax products must remain frozen throughout the distribution and delivery process, until the time of administration to the patient, and cannot be handled at room temperature. In addition, our DCVax product candidates are personalized and they involve ongoing treatment cycles over several years for each patient. Each product shipment for each patient must be tracked and managed individually. For all of these reasons, among others, we will not be able to simply use the distribution networks and processes that already exist for conventional drugs. It may take time for shipping companies, hospitals, pharmacies and physicians to adapt to the requirements for handling, distribution and delivery of these products, which may adversely affect our commercialization.

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Our product candidates will require different marketing and sales methods and personnel than conventional therapeutic products. Also, we lack sales and marketing experience. These factors may result in significant difficulties in commercializing our product candidates.

The commercial success of any of our product candidates will depend upon the strength of our sales and marketing efforts. We do not have a marketing or sales force and have no experience in marketing or sales of products like our lead product, DCVax-L for GBM. To fully commercialize our product candidates, we will need to recruit and train marketing staff and a sales force with technical expertise and ability to manage the distribution of our DCVax-L for GBM. As an alternative, we could seek assistance from a corporate partner or a third party services firm with a large distribution system and a large direct sales force. However, since our DCVax living cell, immune therapy products are a fundamentally new and different type of product than are on the market today, we would still have to train such partner’s or such services firms’ personnel about our products, and would have to make changes in their distribution processes and systems to handle our products. We may be unable to recruit and train effective sales and marketing forces or our own, or of a partner or a services firm, and/or doing so may be more costly and difficult than anticipated. Such factors may result in significant difficulties in commercializing our product candidates, and we may be unable to generate significant revenues.

We may not obtain or maintain the benefits associated with orphan drug status, including market exclusivity.

Although our lead product, DCVax-L for GBM, has been granted orphan drug status in both the United States and the European Union, or EU, we may not receive the benefits associated with orphan drug designation (including the benefit providing for market exclusivity for a number of years). This may result from a failure to maintain orphan drug status, or result from a competing product reaching the market that has an orphan designation for the same disease indication. Under U.S. and EU rules for orphan drugs, if such a competing product reaches the market before ours does, the competing product could potentially obtain a scope of market exclusivity that limits or precludes our product from being sold in the U.S. for seven years or from being sold in the EU for ten years. Also, in the EU, even after orphan status has been granted, that status is re-examined shortly prior to the product receiving any regulatory approval. The EMA must be satisfied that there is evidence that the product offers a significant benefit relative to existing therapies, in order for the therapeutic product to maintain its orphan drug status. Accordingly, our product candidates will have to re-qualify for orphan drug status prior to any potential product approval in the EU.

The availability and amount of potential reimbursement for our product candidates by government and private payers is uncertain and may be delayed and/or inadequate.

The availability and extent of reimbursement by governmental and/or private payers is essential for most patients to be able to afford expensive treatments, such as cancer treatments. In the United States, the principal decisions about reimbursement for new medicines are typically made by the Centers for Medicare & Medicaid Services, or CMS, an agency within the U.S. Department of Health and Human Services, as CMS decides whether and to what extent a new medicine will be covered and reimbursed under Medicare. Private payers tend to follow CMS to a substantial degree. It is difficult to predict what CMS will decide with respect to reimbursement for fundamentally novel products such as ours, as there is no body of established practices and precedents for these new products. To date, we are aware of only one active immune therapy that has reached the stage of a reimbursement decision (Provenge). Although CMS approved coverage and reimbursement for Provenge, and private payers followed suit, there remain substantial questions and concerns about reimbursement for Provenge, and such questions and concerns appear to be impeding sales.

Reimbursement agencies in Europe can be even more conservative than CMS in the U.S.. A number of cancer drugs which have been approved for reimbursement in the U.S. have not been approved for reimbursement in certain European countries, and/or the level of reimbursement approved in Europe is lower than in the U.S.

Various factors could increase the difficulties for our DCVax products to obtain reimbursement. Costs and/or difficulties associated with the reimbursement of Provenge could create an adverse environment for reimbursement of other immune therapies, such as our DCVax products. Approval of other competing products (drugs and/or devices) for the same disease indications could make the need for our products and the cost-benefit balance seem less compelling. The cost structure of our product is not a typical cost structure for

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medical products, as the majority of our costs are incurred up front, when the manufacturing of the personalized product is done. Our atypical cost structure may not be accommodated in any reimbursement for our products. If we are unable to obtain adequate levels of reimbursement, our ability to successfully market and sell our product candidates will be adversely affected.

The manner and level at which reimbursement is provided for services related to our product candidates (e.g., for administration of our product to patients) is also important. If the reimbursement for such services is inadequate, that may lead to physician resistance and adversely affect our ability to market or sell our products.

The methodology under which CMS makes coverage and reimbursement determinations is subject to change, particularly because of budgetary pressures facing the Medicare program. For example, the Medicare Prescription Drug, Improvement, and Modernization Act, or Medicare Modernization Act, enacted in 2003, provided for a change in reimbursement methodology that has reduced the Medicare reimbursement rates for many drugs, including oncology therapeutics.

In markets outside the U.S., where we plan to operate in the future, the prices of medical products are subject to direct price controls and/or to reimbursement with varying price control mechanisms, as part of national health systems. In general, the prices of medicines under such systems are substantially lower than in the U.S. Some jurisdictions operate positive and/or negative list systems under which products may only be marketed once a reimbursement price has been agreed. Other countries allow companies to fix their own prices for medicines, but monitor and control company profits. The downward pressure on health care costs in general, particularly prescription drugs, has become very intense. As a result, increasingly high barriers are being erected to the entry of new products. Accordingly, in markets outside the U.S., the reimbursement for our products may be reduced compared with the U.S. and may be insufficient to generate commercially reasonable revenues and profits.

Competition in the biotechnology and biopharmaceutical industry is intense and most of our competitors have substantially greater resources than we do.

The biotechnology and biopharmaceutical industries are characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary products. Several companies, such as Dendreon, Celldex Therapeutics, Inc., Ark Therapeutics plc, Oxford Biomedica plc, Argos Therapeutics, Inc., Agenus, Inc., Prima Biomed, Ltd., Avax Technologies, Inc., Immunocellular Therapeutics, Ltd., Bavarian Nordic, Bellicum Pharmaceuticals, and others are actively involved in the research and development of immune therapies or cell-based therapies for cancer. In addition, other novel technologies for cancer are under development, such as the electro-therapy device of NovoCure. Of these companies, only one has obtained approval of such an immune therapy: Dendreon (for its Provenge treatment of prostate cancer). Additionally, several companies, such as Medarex, Inc., Amgen, Inc., Agensys, Inc., and Genentech, Inc., are actively involved in the research and development of monoclonal antibody-based cancer therapies. Currently, at least seven antibody-based products are approved for commercial sale for cancer therapy, and a large number of additional ones are under development. Genentech is also engaged in several Phase III clinical trials for additional antibody-based therapeutics for a variety of cancers, and several other companies are in early stage clinical trials for such products. Many other third parties compete with us in developing alternative therapies to treat cancer, including: biopharmaceutical companies; biotechnology companies; pharmaceutical companies; academic institutions; and other research organizations, as well as some medical device companies (e.g., NovoCure and MagForce Nano Technologies AG).

We face extensive competition from companies developing new treatments for brain cancer. These include a variety of immune therapies, as mentioned above, as well as a variety of small molecule drugs and biologics drugs . There are also a number of existing drugs used for the treatment of brain cancer that may compete with our product, including, Avastin® (Roche Holding AG), Gliadel® (Eisai Co. Ltd.), and Temodar® (Merck & Co., Inc.), as well as Novocure’s electrotherapy device.

Most of our competitors have significantly greater financial resources and expertise in research and development, manufacturing, pre-clinical testing, conducting clinical trials, obtaining regulatory approvals and marketing and sales than we do. Smaller or early-stage companies may also prove to be significant competitors, particularly if they enter into collaborative arrangements with large and established companies.

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These third parties compete with us in recruiting and retaining qualified scientific and management personnel, as well as in acquiring technologies complementary to our programs, and in obtaining sites for our clinical trials and enrolling patients.

Our competitors may develop more effective or affordable products, or achieve earlier patent protection or earlier product marketing and sales. Any products developed by us may be rendered obsolete and non-competitive.

Competing generic medicinal products may be approved.

In the EU, there exists a process for approval of generic biological medicinal products once patent protection and other forms of data and market exclusivity have expired. Arrangements for approval of generic biologics products exist and are under consideration in the U.S., as well. Other jurisdictions are considering adopting legislation that would allow the approval of generic biological medicinal products. If generic medicinal products are approved, competition from such products may substantially reduce sales of our products.

We may be exposed to potential product liability claims, and our existing insurance may not cover these claims in whole or in part. In addition, insurance against such claims may not be available to us on reasonable terms in the future, if at all.

Our business exposes us to potential product liability risks that are inherent in the testing, manufacturing, marketing and sale of therapeutic products. We carry insurance coverage but this insurance may not cover any claims made. In the future, insurance coverage may not be available to us on commercially reasonable terms (including acceptable cost), if at all. Insurance that we obtain may not be adequate to cover claims against us. Regardless of whether they have any merit or not, and regardless of their eventual outcome, product liability claims may result in substantially decreased demand for our product candidates, injury to our reputation, withdrawal of clinical trial participants or physicians, and/or loss of revenues. Thus, whether or not we are insured, a product liability claim or product recall may result in losses that could be material.

We store, handle, use and dispose of controlled hazardous, radioactive and biological materials in our business. Our current use of these materials generally is below thresholds giving rise to burdensome regulatory requirements. Our development efforts, however, may result in our becoming subject to additional requirements, and if we fail to comply with applicable requirements we could be subject to substantial fines and other sanctions, delays in research and production, and increased operating costs. In addition, if regulated materials were improperly released at our current or former facilities or at locations to which we send materials for disposal, we could be liable for substantial damages and costs, including cleanup costs and personal injury or property damages, and we could incur delays in research and production and increased operating costs.

Insurance covering certain types of claims of environmental damage or injury resulting from the use of these materials is available but can be expensive and is limited in its coverage. We have no insurance specifically covering environmental risks or personal injury from the use of these materials and if such use results in liability, our business may be seriously harmed.

Our intellectual property rights may be overturned, narrowed or blocked, and may not provide sufficient commercial protection for our product candidates, or third parties may infringe upon our intellectual property.

Patent laws afford only limited protection and may not protect our rights to the extent necessary to sustain any competitive advantage we may have. In addition, the laws of some foreign countries do not protect proprietary rights to the same extent as the laws of the United States, and we may encounter significant problems in protecting our proprietary rights in those countries. Moreover patents and patent applications relating to living cell products are relatively new, involve complex factual and legal issues, and are largely untested in litigation — and as a result, are uncertain. Third parties may challenge our existing patents, and such challenges could result in overturning or narrowing some of our patents. Even if our patents are not challenged, third parties could assert that their patents block some or all of our patents

As of November 28, 2012, we have over 100 issued patents (7 in the U.S.) and more than 90 pending patent applications related to our product candidates, and related processes such as manufacturing processes.

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The issued patents expire at various dates from 2015 to 2026. Our issued patents may be challenged, and such challenges may result in reductions in scope or invalidations. Our pending patent applications may not result in issued patents. Moreover, our patents and patent applications may not be sufficiently broad to prevent others from using substantially similar technologies or from developing competing products. We also face the risk that others may independently develop similar or alternative technologies, or design around our patented technologies.

We have taken security measures (including execution of confidentiality agreements) to protect our proprietary information, especially proprietary information that is not covered by patents or patent applications. These measures, however, may not provide adequate protection for our trade secrets or other proprietary information. In addition, others may independently develop substantially equivalent proprietary information or techniques or otherwise gain access to our trade secrets.

We may be exposed to claims or lawsuits — with or without merit — on various subjects, including that our products infringe patents or other proprietary rights of other parties.

There is a substantial amount of litigation involving patent and other intellectual property rights in the biotechnology and biopharmaceutical industries generally. The patent landscape is especially uncertain in regard to cell therapy products, as it involves complex legal and factual questions for which important legal principles remain unresolved. Infringement and other intellectual property claims — with or without merit — can be expensive and time-consuming to litigate and can divert management’s attention. We have already been exposed to one frivolous patent lawsuit by a large company, which we vigorously defended and forced the large company to withdraw all of the claims made. We have also been exposed to frivolous claims (without a lawsuit) by a competitor asserting or implying inaccurately that a recent patent issued to them somehow covers our products (which it does not). In the future, we may again be exposed to claims by third parties — with or without merit — that our products infringe their intellectual property rights. Such claims or lawsuits may involve substantial costs and diversion of management attention to defend.

In addition, because patents can take many years to issue, and patent applications are not published until up to eighteen months after they are filed, there may be currently pending applications, unknown to us, which may later result in issued patents that our products may inadvertently infringe. There could also be existing patents of which we are not aware that one or more of our products may inadvertently infringe.

DCVax is our only technology in clinical development.

Unlike many pharmaceutical companies that have a number of products in development and which utilize many different technologies, we are dependent on the success of our DCVax platform technology. While the DCVax technology has a wide scope of potential use, and is embodied in several different product lines for different clinical situations, if the core DCVax technology is not effective or is not commercially viable, our business could fail. We do not currently have other technologies that could provide alternative support for us.

Collaborations play an important role in our business, and could be vulnerable to competition or termination.

We work with scientists and medical professionals at academic and other institutions, including UCLA, among others, some of whom have conducted research for us or have assisted in developing our research and development strategy. These scientists and medical professionals are collaborators, not our employees. They may have commitments to, or contracts with, other businesses or institutions that limit the amount of time they have available to work with us. We have little control over these individuals. We can only expect that they devote time to us and our programs as required by any license, consulting or sponsored research agreements we may have with them. In addition, these individuals may have arrangements with other companies to assist in developing technologies that may compete with our products. If these individuals do not devote sufficient time and resources to our programs, or if they provide substantial assistance to our competitors, our business could be seriously harmed.

The success of our business strategy may partially depend upon our ability to develop and maintain our collaborations and to manage them effectively. Due to concerns regarding our ability to continue our operations or the commercial feasibility of our personalized DCVax product candidates, these third parties

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may decide not to conduct business with us or may conduct business with us on terms that are less favorable than those customarily extended by them. If either of these events occurs, our business could suffer significantly.

We may have disputes with our collaborators, which could be costly and time consuming. Failure to successfully defend our rights could seriously harm our business, financial condition and operating results. We intend to continue to enter into collaborations in the future. However, we may be unable to successfully negotiate any additional collaboration and any of these relationships, if established, may not be scientifically or commercially successful.

Our business could be adversely affected by new legislation and/or product related issues.

Changes in applicable legislation and/or regulatory policies or discovery of problems with the product, production process, site or manufacturer may result in delays in bringing products to market, the imposition of restrictions on the product’s sale or manufacture, including the possible withdrawal of the product from the market, or may otherwise have an adverse effect on our business.

Our business could be adversely affected by animal rights activists.

Our business activities have involved animal testing, as such testing is required before new medical products can be tested in clinical trials in patients. Animal testing has been the subject of controversy and adverse publicity. Some organizations and individuals have attempted to stop animal testing by pressing for legislation and regulation in these areas. To the extent that the activities of such groups are successful, our business could be adversely affected. Negative publicity about us, our pre-clinical trials and our product candidates could also adversely affect our business.

Risks Related to our Common Stock and this Offering

There may not be an active, liquid trading market for our common stock and warrants.

Our common stock is currently listed on the OTCQB, which is generally recognized as being a less active market than NASDAQ. In addition, there is no established trading market for the warrants being offered in this offering. The pool of potential investors who may buy and sell on the OTCQB is limited. Many institutional investors have policies which preclude them from doing so. You may not be able to sell your shares at the time desired or at the price desired. There may be significant consequences associated with our stock trading on the OTCQB rather than a national exchange. The effects of not being able to list our securities on a national exchange include:

The market for our common stock may be limited, because our common stock is subject to “penny stock” rules.

Our common stock is subject to the SEC’s “penny stock” rules. As a result, broker-dealers may experience difficulty in completing customer transactions, and trading activity in our securities may be adversely affected. Under the “penny stock” rules promulgated under the Securities Exchange Act of 1934, as amended, or Exchange Act, broker-dealers who recommend such securities to persons other than institutional accredited investors must:

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As a result of these rules, broker-dealers may find it difficult to effectuate customer transactions, and trading activity in our common stock may be adversely affected. As a result, the market price of our common stock may be depressed, and stockholders may find it more difficult to sell our common stock.

Your ability to sell your shares in the secondary trading market may be limited, because our common stock is quoted on the OTCQB.

Our common stock is currently quoted on the over-the-counter market on the OTCQB, as described above. Consequently, the liquidity of our common stock is quite limited, not only in regard to the number of shares that are bought and sold, but also through delays in the timing of transactions, and lack of coverage by security analysts and the news media of our Company. As a result, prices for shares of our common stock may be lower than might otherwise be the case if our common stock were quoted and traded on NASDAQ or a national securities exchange.

The price of our common stock may be highly volatile.

The share prices of publicly traded biotechnology and emerging pharmaceutical companies, particularly companies without consistent product revenues and earnings, can be highly volatile and are likely to remain highly volatile in the future. The price which investors may realize in sales of their shares of our common stock may be materially different than the price at which our common stock is quoted, and will be influenced by a large number of factors, some specific to us and our operations, and some unrelated to our operations. Such factors may cause the price of our stock to fluctuate frequently and substantially. Such factors may include large purchases or sales of our common stock, positive or negative events relating to other companies developing immune therapies for cancer, positive or negative events relating to healthcare and the overall pharmaceutical and biotech sector, currency fluctuations, legislative or regulatory changes, and/or general economic conditions. In the past, shareholder class action litigation has been brought against other companies that experienced volatility in the market price of their shares. Whether or not meritorious, litigation brought against a company following fluctuations in the trading price of its common stock can result in substantial costs, divert management’s attention and resources, and harm the company’s financial condition and results of operations.

Speculative nature of warrants.

The warrants do not confer any rights of common stock ownership on its holders, such as voting rights or the right to receive dividends, but rather merely represent the right to acquire shares of common stock at a fixed price for a limited period of time. Specifically, commencing on the date of issuance, holders of the warrants may exercise their right to acquire the common stock and pay an exercise price of $___ per share [125% of public offering price of the common stock and warrants], prior to five years from the date of issuance, after which date any unexercised warrants will expire and have no further value. Moreover, following this offering, the market value of the warrants is uncertain and there can be no assurance that the market value of the warrants will equal or exceed their public offering price. There can be no assurance that the market price of the common stock will ever equal or exceed the exercise price of the warrants, and consequently, whether it will ever be profitable for holders of the warrants to exercise the warrants.

Toucan Capital and its affiliates are the principal holders of our shares of common stock, and this concentration of ownership may have a negative effect on the market price of our common stock.

As of November 28, 2012, Toucan Capital and its affiliates (including Cognate BioServices, Toucan Partners and Linda Powers, who also serves as our Chief Executive Officer and Chairperson of the Board of Directors), collectively, beneficially owned an aggregate of 8,188,050 shares of our common stock, representing approximately 48.0 percent of our issued and outstanding common stock. This concentration of

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ownership may adversely affect the trading price of our common stock because investors may perceive disadvantages in owning stock of companies with controlling stockholders. Toucan Capital and its affiliates have the ability to exert substantial influence over all matters requiring approval by our stockholders, including the election and removal of directors and any proposed merger, consolidation or sale of all or substantially all of our assets. This influence could have the effect of delaying, deferring or preventing a change in control, or impeding a merger or consolidation, takeover or other business combination that could be favorable to investors.

The requirements of the Sarbanes-Oxley Act of 2002 and other U.S. securities laws impose substantial costs, and may drain our resources and distract our management.

We are subject to certain of the requirements of the Sarbanes-Oxley Act of 2002 in the U.S., as well as the reporting requirements under the Exchange Act. The Exchange Act requires, among other things, filing of annual reports on Form 10-K, quarterly reports on Form 10-Q and periodic reports on Form 8-K following the happening of certain material events, with respect to our business and financial condition. The Sarbanes-Oxley Act requires, among other things, that we maintain effective disclosure controls and procedures and internal controls over financial reporting. Our existing controls have some weaknesses, as described below. Meeting the requirements of the Exchange Act and the Sarbanes-Oxley Act may strain our resources and may divert management's attention from other business concerns, both of which may have a material adverse effect on our business.

Our management and our independent auditor have identified internal control deficiencies, which our management and our independent auditor believe constitute material weaknesses.

In connection with the preparation of our financial statements for the year ended December 31, 2011, and prior years, our management and our independent auditor identified certain internal control deficiencies that, in the aggregate, represent material weaknesses, including:

As part of our independent auditors’ communications with our audit committee with respect to audit procedures for the year ended December 31, 2011, our independent auditors informed the audit committee that these deficiencies constituted material weaknesses, as defined by Auditing Standard No. 5, “An Audit of Internal Control Over Financial Reporting that is Integrated with an Audit of Financial Statements and Related Independence Rule and Conforming Amendments,” established by the Public Company Accounting Oversight Board, or PCAOB. We have begun taking appropriate and reasonable steps, and will continue and complete such steps in due course, to make the necessary improvements to address these deficiencies, but the timing of such steps is uncertain and the availability of funding and resources for such steps are also uncertain. Our ability to attract qualified individuals to serve on our Board and to take on key management roles within the Company is also uncertain. Our failure to successfully complete the remedies of the existing weaknesses could lead to heightened risk for financial reporting mistakes and irregularities, and/or lead to a loss of public confidence in our internal controls that could have a negative effect on the market price of our common stock.

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We do not intend to pay any cash dividends in the foreseeable future and, therefore, any return on your investment in our common stock must come from increases in the market price of our common stock.

We have not paid any cash dividends on our common stock to date in our history, and we do not intend to pay cash dividends on our common stock in the foreseeable future. We intend to retain future earnings, if any, for reinvestment in the development and expansion of our business. Also, any credit agreements which we may enter into with institutional lenders may restrict our ability to pay dividends. Therefore, any return on your investment in our capital stock must come from increases in the fair market value and trading price of our common stock. Such increases in the trading price of our stock may not occur.

Substantial amounts of our previously issued common stock are now and/or will soon be eligible for re-sale under Rule 144. This may have a negative effect on the market price of our common stock.

In general, under Rule 144, a person (or persons whose shares are aggregated) who has satisfied a six- month holding period may, under certain circumstances, sell within any three-month period a number of securities which does not exceed the greater of 1% of the then outstanding shares of common stock or the average weekly trading volume of the class during the four calendar weeks prior to such sale. In addition, under certain circumstances Rule 144 also permits the sale of securities, without any limitation, by a person who is not our affiliate (as such term is defined in Rule 144(a)(1)), and who has satisfied a one-year holding period.

As of November 28, 2012, 9,334,101 shares of our common stock were previously issued as restricted securities under Rule 144 of the Securities Act of 1933, as amended. All of such restricted stock has been outstanding for more than six months and all of these shares may be resold without restriction pursuant to Rule 144. If substantial amounts of such shares are sold pursuant to Rule 144, this may have a negative effect on the market price of our common stock.

In addition, we have executed agreements to retire approximately $34.5 million aggregate amount of convertible notes, notes and payables in exchange for 9,199,998 shares of common stock and warrants exercisable for 4,599,994 shares of common stock effective upon the closing of this offering. Approximately $4.7 million aggregate principal amount of convertible notes will be outstanding after the offering. We intend to enter into agreements after this offering to convert a portion of the convertible notes into common stock and warrants. Future issuances or sales of our common stock, or the availability of our common stock for issuance or sale, may harm the market price of our common stock or our ability to raise capital.

The warrants being offered pursuant to this prospectus entitle the holders of such warrants to purchase up to an aggregate 1,125,000 shares of common stock at any time from the date of issuance until five years from such date. Sales of either the warrants or the underlying shares of common stock or even the existence of the warrants, may depress the price of the common stock or the warrants in any markets that may develop for such securities.

Our certificate of incorporation and bylaws, our shareholder rights plan and Delaware law have anti-takeover provisions that could discourage, delay or prevent a change in control, which may cause our stock price to decline.

Our certificate of incorporation and bylaws and Delaware law contain provisions which could make it more difficult for a third party to acquire us, even if closing such a transaction would be beneficial to our stockholders. We are authorized to issue up to 40,000,000 shares of preferred stock. This preferred stock may be issued in one or more series, the terms of which may be determined at the time of issuance by our Board of Directors without further action by stockholders. The terms of any series of preferred stock may include voting rights (including the right to vote as a series on particular matters), preferences as to dividend, liquidation, conversion and redemption rights and sinking fund provisions. No preferred stock is currently outstanding. The issuance of any preferred stock could materially adversely affect the rights of the holders of our common stock, and therefore, reduce the value of our common stock. In particular, specific rights granted to future holders of preferred stock could be used to restrict our ability to merge with, or sell our assets to, a third party and thereby preserve control by the present management.

Provisions of our certificate of incorporation and bylaws and Delaware law also could have the effect of discouraging potential acquisition proposals or making a tender offer or delaying or preventing a change in

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control, including changes a stockholder might consider favorable. Such provisions may also prevent or frustrate attempts by our stockholders to replace or remove our management. In particular, the certificate of incorporation and bylaws and Delaware law, as applicable, among other things:

We expect to adopt a shareholder rights plan and declare a dividend distribution of one right for each outstanding share of common stock as fixed by our Board of Directors. Each right, when exercisable, will entitle the registered holder to purchase from us shares of a new series of preferred stock on the terms stated in the rights plan. The rights will generally separate from the common stock and become exercisable if any person or group acquires or announces a tender offer to acquire 15% or more of our outstanding common stock without the consent of our Board of Directors. Because the rights may substantially dilute the stock ownership of a person or group attempting to take us over without the approval of our Board of Directors, our stockholder rights plan could make it more difficult for a third party to acquire us (or a significant percentage of our outstanding capital stock) without first negotiating with our Board of Directors.

We are also subject to Section 203 of the Delaware General Corporation Law which, subject to certain exceptions, prohibits “business combinations” between a publicly-held Delaware corporation and an “interested stockholder,” which is generally defined as a stockholder who becomes a beneficial owner of 15% or more of a Delaware corporation’s voting stock for a three-year period following the date that such stockholder became an interested stockholder.

These provisions are expected to discourage certain types of coercive takeover practices and inadequate takeover bids and to encourage persons seeking to acquire control of our company to first negotiate with its board. These provisions may delay or prevent someone from acquiring or merging with us, which may cause the market price of our common stock to decline.

Our management will have broad discretion over the use of the net proceeds from this offering and we may use the net proceeds in ways with which you disagree or which do not produce beneficial results.

We currently intend to use the net proceeds from this offering to fund our research and development activities and for working capital and general corporate purposes. We may also use a portion of the net proceeds to repay up to $3.8 million aggregate principal amount of convertible notes and notes. We have not allocated specific amounts of the net proceeds from this offering for any of the foregoing purposes. Accordingly, our management will have significant discretion and flexibility in applying the net proceeds of this offering. You will be relying on the judgment of our management with regard to the use of these net proceeds, and you will not have the opportunity, as part of your investment decision, to assess whether the proceeds are being used appropriately. It is possible that the net proceeds will be invested in a way that does not yield a favorable, or any, return for us or our stockholders. The failure of our management to use such funds effectively could have a material adverse effect on our business, prospects, financial condition, and results of operation.

You will experience immediate and substantial dilution as a result of this offering and may experience additional dilution in the future as we do further financings and transactions.

You will incur immediate and substantial dilution as a result of this offering. After giving effect to the sale by us of up to 2,250,000 shares of common stock and warrants to purchase up to an aggregate 1,125,000 shares of common stock offered in this offering at an assumed public offering price of $6.00 per share, and after deducting the underwriter’s discount and estimated offering expenses payable by us, investors in this offering can expect an immediate dilution of $5.40 per share. In addition, in the past, we issued options and warrants to acquire shares of common stock. To the extent these options or warrants are ultimately exercised, you will sustain further future dilution.

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Risks Related to Our Reverse Stock Split

Our reverse stock split may not increase our stock price sufficiently to enable us to list our common stock on The NASDAQ Capital Market, in which case this offering will not be completed.

We expect that the 1-for-16 reverse stock split of our outstanding common stock which was effected on September 25, 2012 will increase the market price of our common stock so that we will be able to meet the minimum bid price requirement of the Listing Rules of The NASDAQ Capital Market. However, the effect of a reverse stock split upon the market price of our common stock cannot be predicted with certainty, and the results of reverse stock splits by companies in similar circumstances have been varied. It is possible that the market price of our common stock following the reverse stock split will not increase sufficiently for us to be in compliance with the minimum bid price requirement. If we are unable meet the minimum bid price requirement, we may be unable to list our shares on The NASDAQ Capital Market, in which case this offering will not be completed.

Even if the reverse stock split achieves the requisite increase in the market price of our common stock, we cannot assure you that we will be able to continue to comply with the minimum bid price requirement of The NASDAQ Capital Market.

Even if the reverse stock split achieves the requisite increase in the market price of our common stock to be in compliance with the minimum bid price of The NASDAQ Capital Market, there can be no assurance that the market price of our common stock following the reverse stock split will remain at the level required for continuing compliance with that requirement. It is not uncommon for the market price of a company’s common stock to decline in the period following a reverse stock split. If the market price of our common stock declines following the effectuation of a reverse stock split, the percentage decline may be greater than would occur in the absence of a reverse stock split. In any event, other factors unrelated to the number of shares of our common stock outstanding, such as negative financial or operational results, could adversely affect the market price of our common stock and jeopardize our ability to meet or maintain The NASDAQ Capital Market’s minimum bid price requirement. In addition to specific listing and maintenance standards, The NASDAQ Capital Market has broad discretionary authority over the initial and continued listing of securities, which it could exercise with respect to the listing of our common stock.

Even if the reverse stock split increases the market price of our common stock, there can be no assurance that we will be able to comply with other continued listing standards of The NASDAQ Capital Market.

Even if the market price of our common stock increases sufficiently so that we comply with the minimum bid price requirement, there can be no assurance that we will be able to comply with the other standards that we are required to meet in order to maintain a listing of our common stock on The NASDAQ Capital Market. Our failure to meet these requirements may result in our common stock being delisted from The NASDAQ Capital Market, irrespective of our compliance with the minimum bid price requirement.

The reverse stock split may decrease the liquidity of the shares of our common stock.

The liquidity of the shares of our common stock may be affected adversely by the reverse stock split given the reduced number of shares that will be outstanding following the reverse stock split, especially if the market price of our common stock does not increase following the reverse stock split. In addition, the reverse stock split may increase the number of stockholders who own odd lots (less than 100 shares) of our common stock, creating the potential for such stockholders to experience an increase in the cost of selling their shares and greater difficulty effecting such sales.

Following the reverse stock split, the resulting market price of our common stock may not attract new investors, including institutional investors, and may not satisfy the investing requirements of those investors. Consequently, the trading liquidity of our common stock may not improve.

Although we believe that a higher market price of our common stock may help generate greater or broader investor interest, there can be no assurance that the reverse stock split will result in a share price that will attract new investors, including institutional investors. In addition, there can be no assurance that the market price of our common stock will satisfy the investing requirements of those investors. As a result, the trading liquidity of our common stock may not necessarily improve.

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