Our business is subject to numerous risks. We caution you that the following important factors, among others, could cause our actual results to differ materially from those expressed statements made by us or on our behalf in filings with the SEC, press releases, communications with investors and oral statements. Any or all of our statements in this annual report and in any other public statements we make may turn out to be wrong. They can be affected by inaccurate assumptions or by known or unknown risks and uncertainties. Many factors mentioned in the discussion below will be important in determining future results. Consequently, actual future results may vary materially from those anticipated in this annual report.

Risks Relating to Galena’s Business and Industry

We recently changed our strategic focus, and the anticipated benefits of our new strategic focus may not be realized.

You may have difficulty evaluating our business, because we acquired Apthera during 2011 and spun off RXi in 2012. Following the partial spin-off of RXi, our financial statements no longer reflect the consolidated financial condition and results of operations of RXi, and we account for our partial ownership of RXi based on the cost method of accounting. We may pursue selective acquisitions of other cancer treatments to complement or add to our existing cancer immunotherapies. For these reasons, the historical consolidated financial information incorporated by reference in this prospectus do not necessarily reflect the financial condition, results of operations or cash flows that we will achieve in the future.

There also is no assurance that we will be successful in implementing our new focus as an oncology product development and cancer treatment pipeline company.

We are largely dependent on the success of our two leading drug candidates, neither of which may receive regulatory approval or be successfully commercialized.

Our business prospects depend heavily on successfully developing and commercializing our lead product candidate, NeuVax. On May 8, 2009, we submitted an SPA for a Phase 3 clinical trial for NeuVax, but did not include required chemistry, manufacturing, and controls (“CMC”) information. In July 2009, FDA placed our IND application for a Phase 3 trial for NeuVax on partial clinical hold pending submission of the missing CMC information. We submitted the CMC information August 8, 2011, and the FDA removed the partial clinical hold on September 7, 2011, allowing us to proceed with the Phase 3 clinical trial. The FDA has agreed in the SPA for our Phase 3 PRESENT clinical trial of NeuVax that the design, resulting data, and planned analyses of the Phase 3 study support an acceptable regulatory submission for marketing approval. There is no assurance, however, that the Phase 3 study will be successful, that a single Phase 3 trial will support marketing approval, or that we will be able to obtain marketing approval for NeuVax or any other product candidate.

We currently generate no revenue from sales, and we may never be able to develop marketable products. Before they can be marketed, our products in development must be approved by the FDA or similar foreign governmental agencies. The process for obtaining FDA approval is both time-consuming and costly, with no certainty of a successful outcome. Before obtaining regulatory approval for the sale of any drug candidate, we must conduct extensive preclinical tests and clinical trials to demonstrate the safety and efficacy in humans of our product candidates. Although NeuVax has exhibited no serious adverse events (SAEs) associated with the drug in the Phase 1/2 clinical trial, further testing in our Phase 3 trial may undermine those determinations or unexpected side effects may arise. A failure of any preclinical study or clinical trial can occur at any stage of testing. The results of preclinical and initial clinical testing of these products may not necessarily indicate the results that will be obtained from later or more extensive testing. It also is possible to suffer significant setbacks in advanced clinical trials, even after obtaining promising results in earlier trials.

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A number of different factors could prevent us from obtaining regulatory approval or commercializing our product candidates on a timely basis, or at all.

We, the FDA or other applicable regulatory authorities or an institutional review board, or “ IRB ,” which is an independent committee under the oversight of the United States Department of Health and Human Services, or “ HHS ,” that has been formally registered with HHS and functions to approve, monitor and review biomedical and behavioral research involving humans, may suspend clinical trials of a drug candidate at any time for various reasons, including if we or they believe the subjects or patients participating in such trials are being exposed to unacceptable health risks. Among other reasons, adverse side effects of a drug candidate on subjects or patients in a clinical trial could result in the FDA or other regulatory authorities suspending or terminating the trial and refusing to approve a particular drug candidate for any or all indications of use.

Clinical trials of a new drug candidate require the enrollment of a sufficient number of patients, including patients who are suffering from the disease the drug candidate is intended to treat and who meet other eligibility criteria. Rates of patient enrollment are affected by many factors, and delays in patient enrollment can result in increased costs and longer development times.

Clinical trials also require the review and oversight of IRBs, which approve and continually review clinical investigations and protect the rights and welfare of human subjects. An inability or delay in obtaining IRB approval could prevent or delay the initiation and completion of clinical trials, and the FDA may decide not to consider any data or information derived from a clinical investigation not subject to initial and continuing IRB review and approval.

In addition, cancer vaccines are a relatively new form of therapeutic and a very limited number of such products have received regulatory approval. Therefore, the FDA or other regulatory authority may apply standards for approval of a new cancer vaccine that is different from past experience.

Numerous factors could affect the timing, cost or outcome of our drug development efforts, including the following:

It is possible that none of the product candidates that we develop will obtain the appropriate regulatory approvals necessary for us to begin selling them or that any regulatory approval to market a product may be subject to limitations on the indicated uses for which we may market the product. The time required to obtain FDA and other approvals is unpredictable but often can take years

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following the commencement of clinical trials, depending upon the complexity of the drug candidate. Any analysis we perform of data from clinical activities is subject to confirmation and interpretation by regulatory authorities, which could delay, limit or prevent regulatory approval. Any delay or failure in obtaining required approvals could have a material adverse effect on our ability to generate revenue from the particular drug candidate.

We are also subject to numerous foreign regulatory requirements governing the conduct of clinical trials, manufacturing and marketing authorization, pricing and third-party reimbursement. The foreign regulatory approval process includes all of the risks associated with the FDA approval described above as well as risks attributable to the satisfaction of local regulations in foreign jurisdictions. Approval by the FDA does not assure approval by regulatory authorities outside of the United States.

We experienced interruptions in the supply of a NeuVax component that delayed patient enrollment in our Phase 3 PRESENT trial of NeuVax, and we will continue to be dependent upon the sole source of supply of this component.

We do not have the facilities or expertise to manufacture supplies of any of our potential product candidates for clinical trials. Accordingly, we will be dependent upon contract manufacturers for these supplies. There can be no assurance that we will be able to secure needed supply arrangements on attractive terms, or at all. Our failure to secure these arrangements as needed could have a materially adverse effect on our ability to complete the development of our product candidates or, if we obtain regulatory approval for our product candidates, to commercialize them.

Our current plans call for the manufacture of our compounds by contract manufacturers offering research grade, Good Laboratory grade and Good Manufacturing Practices grade materials for preclinical studies ( e.g., toxicology studies) and for clinical use. Certain of our product candidates are complex molecules requiring many synthesis steps, which may lead to challenges with purification and scale-up. These challenges could result in increased costs and delays in manufacturing.

NeuVax is administered in combination with Leukine ^® , a “ GM-CSF “ available in both liquid and lyopholyzed forms exclusively from Genzyme Corporation, or “ Genzyme,” a subsidiary of Sanofi-Aventis. Until mid-2012, we utilized liquid Leukine ^® only in the administration of NeuVax. In June 2012, however, Genzyme recalled all liquid Leukine ^® without explanation, and we began incorporating lyopholyzed Leukine ^® as another option in addition to liquid Leukine ^® in the administration of NeuVax at our Phase 3 PRESENT study sites in the U.S. as permitted by the FDA. We believe our current supply of lyopholyzed GM-CSF is adequate for the completion of our Phase 3 PRESENT trial.

Lyopholyzed Leukine ^® is approved for sale only in the U.S., and we must obtain foreign regulatory approval in order to utilize lyopholyzed Leukine ^® at sites outside the U.S. The regulatory approval process resulted in delays in the planned enrollment of patients at foreign sites for our Phase 3 PRESENT trial, and it is possible that we will be unable to obtain the necessary approvals to use lyopholyzed Leukine ^® at one or more of these foreign sites. Any extended delay or failure in obtaining the necessary approvals could have a material adverse effect on patient enrollment at these sites or the timing of the interim analysis or primary endpoint of our Phase 3 PRESENT trial.

We will continue to be dependent on Genzyme by us for our supply of Leukine ^® in connection with the ongoing NeuVax trials and the eventual commercial manufacture of NeuVax. Any future interruptions in the availability of Leukine ^® , or any determination by us to change the GM-CSF used with NeuVax, may have a material adverse effect on our NeuVax trials and any commercialization of NeuVax.

We may not be able to establish or maintain the third-party relationships that are necessary to develop or potentially commercialize some or all of our product candidates.

We expect to depend on collaborators, partners, licensees, clinical research organizations and other third parties to support our discovery efforts, to formulate product candidates, to manufacture our product candidates, and to conduct clinical trials for some or all of our product candidates. We cannot guarantee that we will be able to successfully negotiate agreements for or maintain relationships with collaborators, partners, licensees, clinical investigators, vendors and other third parties on favorable terms, if at all. Our ability to successfully negotiate such agreements will depend on, among other things, potential partners’ evaluation of the superiority of our technology over competing technologies and the quality of the preclinical and clinical data that we have generated, and the perceived risks specific to developing our product candidates. If we are unable to obtain or maintain these agreements, we may not be able to clinically develop, formulate, manufacture, obtain regulatory approvals for or commercialize our product candidates. Under certain license agreements that we have already entered into, we have minimum dollar amounts per year that we are obligated to spend on the development of the technology we have licensed from our contract partners and other obligations to maintain certain licenses. If we fail to meet this requirement under any of our licenses that contain such requirements or any other obligations under these licenses, we may be in breach of our obligations under such agreement, which may result in the loss of the technology licensed. We cannot necessarily control the amount or timing of resources that our contract partners will devote to our research and development programs, product candidates or potential product candidates, and we cannot guarantee that these parties will fulfill their obligations to us under these arrangements in a timely fashion. We may not be able to readily terminate any such agreements with contract partners even if such contract partners do not fulfill their obligations to us.

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In addition, we may receive notices from third parties from time to time alleging that our technology or product candidates infringe upon the intellectual property rights of those third parties. Any assertion by third parties that our activities or product candidates infringe upon their intellectual property rights may adversely affect our ability to secure strategic partners or licensees for our technology or product candidates or our ability to secure or maintain manufacturers for our compounds.

Even if we obtain regulatory approvals, our marketed drugs will be subject to ongoing regulatory review. If we fail to comply with ongoing regulatory requirements, we could lose our approvals to market drugs and our business would be materially adversely affected.

Following regulatory approval of any drugs we may develop, we will remain subject to continuing regulatory review, including the review of adverse drug experiences and clinical results that are reported after our drug products are made available to patients. This would include results from any post marketing tests or vigilance required as a condition of approval. The manufacturer and manufacturing facilities we use to make any of our drug products will also be subject to periodic review and inspection by the FDA.

The discovery of any new or previously unknown problems with the product, manufacturer or facility may result in restrictions on the drug or manufacturer or facility, including withdrawal of the drug from the market. We would continue to be subject to the FDA requirements 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 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.

Even if we receive regulatory approval to market our product candidates, our product candidates may not be accepted commercially, which may prevent us from becoming profitable.

NeuVax and our other cancer-targeted product candidates may not achieve market acceptance. Factors that we believe will materially affect market acceptance of our product candidates include:

We will be subject to competition and may not be able to compete successfully.

The biotechnology industry, including the cancer therapy vaccines market, is intensely competitive and involves a high degree of risk. We compete with other companies that have far greater experience and financial, research and technical resources than us. Potential competitors in the United States and worldwide are numerous and include pharmaceutical and biotechnology companies, educational institutions and research foundations, many of which have substantially greater capital resources, marketing experience, research and development staffs and facilities than us. Some of our competitors may develop and commercialize products that compete directly with those incorporating our technology, introduce products to market earlier than our products or on a more cost effective basis. We may be unable to effectively develop our technology or any other applications on a cost effective basis or otherwise. In addition, our technology may be subject to competition from other technology or methods developed using techniques other than those developed by traditional biotechnology methods. Our competitors compete with us in recruiting and retaining qualified scientific and management personnel as well as in acquiring technologies complementary to our technology. Our collaborators or we will face competition with respect to product efficacy and safety, ease of use and adaptability to various modes of administration, acceptance by physicians, the timing and scope of regulatory approvals, availability of resources, reimbursement coverage, price and patent position, including potentially dominant patent positions of others. An inability to successfully complete our product development could lead to us having limited prospects for establishing market share or generating revenues from our technology.

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For patients with early stage breast cancer, adjuvant therapy is often given to prevent recurrence and increase the chance of long-term disease free survival. Adjuvant therapy for breast cancer can include chemotherapy, hormonal therapy, radiation therapy, or combinations thereof. In addition, the HER2 targeted drug trastuzumab (Herceptin ^® ) may be given to patients with tumors with high expression of HER2 (IHC 3+), as well as other novel targets such as MUCI which may be useful in treating breast cancer.

There are a number of cancer vaccines in development for breast cancer, including but not limited to Lapuleucel-T (Dendreon), AE-37 (Antigen Express) and Stimuvax (Merck KgA). While these development candidates are aimed at a number of different targets, and AE-37 has published data in the HER2 breast cancer patient population, there is no guarantee that any of the these compounds will not in the future be indicated for treatment of low to intermediate HER2 breast cancer patients and become directly competitive with NeuVax.

We are dependent on technologies we license, and if we lose the right to license such technologies or we fail to license new technologies in the future, our ability to develop new products would be harmed.

We currently are dependent on licenses from third parties for technologies relating to our product candidates. Our current licenses impose, and any future licenses we enter into are likely to impose, various development, funding, royalty, diligence, sublicensing, insurance and other obligations on us. If our license with respect to any of these technologies is terminated for any reason, the development of the products contemplated by the licenses would be delayed, or suspended altogether, while we seek to license similar technology or develop new non-infringing technology. The costs of obtaining new licenses are high.

We may be unable to protect our intellectual property rights licensed from others parties, our intellectual property rights may be inadequate to prevent third parties from using our technologies or developing competing products, and we may need to license additional intellectual property from others.

In addition to our licenses, we also rely on copyright and trademark protection, trade secrets, know-how, continuing technological innovation and licensing opportunities. In an effort to maintain the confidentiality and ownership of our trade secrets and proprietary information, we require our employees, consultants, advisors and others to whom we disclose confidential information to execute confidentiality and proprietary information agreements. However, it is possible that these agreements may be breached, invalidated or rendered unenforceable, and if so, there may not be an adequate corrective remedy available. Furthermore, like many companies in our industry, we may from time to time hire scientific personnel formerly employed by other companies involved in one or more areas similar to the activities we conduct. In some situations, our confidentiality and proprietary information agreements may conflict with, or be subject to, the rights of third parties with whom our employees, consultants or advisors have prior employment or consulting relationships. Although we require our employees and consultants to maintain the confidentiality of all confidential information of previous employers, we may be subject to allegations of trade secret misappropriation or other similar claims as a result of our employees’ or consultants’ prior affiliations. Finally, others may independently develop substantially equivalent proprietary information and techniques, or otherwise gain access to our trade secrets. Our failure to protect our proprietary information and techniques may inhibit or limit our ability to exclude certain competitors from the market and execute our business strategies.

Our success depends upon our ability to obtain and maintain intellectual property protection for our products and technologies.

Our success will depend on our ability to obtain and maintain adequate protection of our intellectual property covering our product candidates and technologies. The ultimate degree of patent protection that will be afforded to biotechnology products and processes, including ours, in the United States and in other important markets remains uncertain and is dependent upon the scope of protection decided upon by the patent offices, courts and lawmakers in these countries. There is no certainty that our existing patents, or patent applications if obtained, will afford us substantial protection or commercial benefit. Similarly, there is no assurance that our pending patent applications or patent applications licensed from third parties will ultimately be granted as patents or that those patents that have been issued or are issued in the future will stand if they are challenged in court.

There is a risk that the products incorporating our NeuVax peptide-based immunotherapy technology or otherwise marketed by us might infringe the patent, trademark or other intellectual property rights of third parties, and there may be patent or other intellectual property rights belonging to others that require us to alter our products, pay licensing fees or cease certain activities. If our products infringe patent or other intellectual property rights of others, the owners of those rights could bring legal actions against us claiming damages and seeking to enjoin manufacture, use, marketing and sales of the affected products. If these legal actions are successful, in addition to any potential liability for damages, we could be required to obtain a license in order to continue to manufacture or market the affected products. We may not prevail in any action brought against us, and any license required under any rights that we infringe may not be available on acceptable terms or at all. Others may attempt to invalidate our intellectual property rights or those of our licensors. Even if our rights, or those of our licensors, are not directly challenged, disputes among third parties could lead to the weakening or invalidation of our intellectual property rights. Any attempt by third parties to undermine or invalidate our intellectual property rights could be costly to defend, require significant time and attention of our management and have a material adverse effect on our business.

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If we are unable to obtain regulatory exclusivity for NeuVax, our business would be adversely affected and such exclusivity may not provide sufficient protection to prevent competitors from entering our markets.

We have issued U.S. composition of matter and use patents and have applied for patents in certain foreign jurisdictions covering our NeuVax product candidate. Because our intellectual property rights to the composition of matter of NeuVax will expire prior to any expected commercialization of NeuVax, we will rely upon our use patent and upon data exclusivity provided under the Federal Food, Drug, and Cosmetic Act and similar laws in other countries and, to a lesser extent, on orphan drug designation, if granted for NeuVax.

We also anticipate that NeuVax will qualify for 12 years of data exclusivity, and thus other companies would be prevented from using our clinical data to support their application for regulatory approval, under the Patient Protection and Affordable Care Act; however, there can be no assurance that the 12 years of exclusivity provided for under the Patient Protection and Affordable Care Act will remain in effect, or that NeuVax will meet the qualifications of a “biological product” to receive the specified period of exclusivity.

We are preparing to apply for Orphan Drug status for NeuVax that, if granted, could provide seven years or ten years of market exclusivity in the United States or the European Union, respectively. However, there is no assurance that the FDA or the European Medicines Agency, or “ EMEA,” will approve our Orphan Drug Application. While the orphan drug designation for NeuVax, if granted, will provide seven years of market exclusivity in the United States, we will not be able to exclude other companies from receiving market approval for the designated orphan indication beyond that timeframe. Even if we have orphan drug designation for a particular drug indication, we cannot guarantee that another company also holding orphan drug designation will not receive FDA approval for the same indication before we do. If that were to happen, our applications for that indication may not be approved until the competing company’s seven-year period of exclusivity expired. Even if we are the first to obtain FDA approval for an orphan drug indication, there are circumstances under which a competing product may be approved for the same indication during our seven-year period of marketing exclusivity, such as if the later product is shown to be clinically superior to the orphan product. Further, the seven-year marketing exclusivity would not prevent competitors from obtaining approval of the same compound for other indications or the use of other types of drugs for the same use as the orphan drug. In addition, data exclusivity does not prevent another company from completing its own clinical trials with NeuVax and obtaining regulatory approval for the same indication for which NeuVax may be approved. Consequently, we may not be able to prevent competitors from entering the market prior to the end of any applicable data exclusivity period. If we are not able to prevent competitors from entering the market with a similar product to NeuVax, our ability to achieve profits from sales of NeuVax will be dramatically limited.

We are subject to potential liabilities from clinical testing and future product liability claims.

If any of our future products are alleged to be defective, they may expose us to claims for personal injury by patients in clinical trials of our products. If our products are approved by the FDA, users may claim that such products caused adverse effects. We will seek to obtain clinical trial insurance for clinical trials that we conduct, as well as liability insurance for any products that we market. There can be no assurance that we will be able to obtain insurance in the amounts we seek, or at all. We anticipate that licensees who develop our products will carry liability insurance covering the clinical testing and marketing of those products. There is no assurance, however, that any insurance maintained by us or our licensees will prove adequate in the event of a claim against us. Even if claims asserted against us are unsuccessful, they may divert management’s attention from our operations and we may have to incur substantial costs to defend such claims.

Any drugs we develop may become subject to unfavorable pricing regulations, third-party reimbursement practices or healthcare reform initiatives, which could have a material adverse effect on our business.

We intend to sell our products primarily to hospitals, oncologists and clinics which receive reimbursement for the health care services they provide to their patients from third-party payors, such as Medicare, Medicaid and other domestic and international government programs, private insurance plans and managed care programs. Most third-party payors may deny reimbursement if they determine that a medical product was not used in accordance with cost-effective treatment methods, as determined by the third-party payor, was used for an unapproved indication or if they believe the cost of the product outweighs its benefits. Third-party payors also may refuse to reimburse for experimental procedures and devices. Furthermore, because our programs are still in development, we are unable at this time to determine their cost-effectiveness and the level or method of reimbursement for them. Increasingly, the third-party payors who reimburse patients are requiring that drug companies provide them with predetermined discounts from list prices, and are challenging the prices charged for medical products. If the price we are able to charge for any products we develop is inadequate in light of our development and other costs, our profitability could be adversely affected.

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We currently expect that any drugs we develop may need to be administered under the supervision of a physician. Under currently applicable law, drugs that are not usually self-administered may be eligible for coverage by the Medicare program if:

Insurers may refuse to provide insurance coverage for newly approved drugs, or insurance coverage may be delayed or be more limited than the purpose for which the drugs are approved by the FDA. Moreover, eligibility for insurance coverage does not imply that any drug will be reimbursed in all cases or at a rate that covers our costs, including research, development, manufacture, sale and distribution. Interim payments for new drugs, if applicable, may also not be sufficient to cover our costs and may not be made permanent. Reimbursement may be based on payments for other services and may reflect budgetary constraints or imperfections in Medicare data. Net prices for drugs may be reduced by mandatory discounts or rebates required by government health care programs or private payors and by any future relaxation of laws that presently restrict imports of drugs from countries where they may be sold at lower prices than in the United States. Third-party payors often rely upon Medicare coverage policy and payment limitations in setting their own reimbursement rates. Our inability to promptly obtain coverage and profitable reimbursement rates from both government-funded and private payors for new drugs that we develop could have a material adverse effect on our operating results, our ability to raise capital needed to develop products, and our overall financial condition.

Additionally, third-party payors are increasingly attempting to contain health care costs by limiting both coverage and the level of reimbursement for medical products and services. Levels of reimbursement may decrease in the future, and future legislation, regulation or reimbursement policies of third-party payors may adversely affect the demand for and price levels of our products. If our customers are not reimbursed for our products, they may reduce or discontinue purchases of our products, which could have a material adverse effect on our business, financial condition and results of operations.

Comprehensive health care reform legislation, which was recently adopted by Congress and was subsequently signed into law, could adversely affect our business and financial condition. Among other provisions, the legislation provides that a “biosimilar” product may be approved by the FDA on the basis of analytical tests and certain clinical studies demonstrating that such product is highly similar to an existing, approved product and that switching between an existing product and the biosimilar product will not result in diminished safety or efficacy. This abbreviated regulatory approval process may result in increased competition if we are able to bring a product to market. The legislation also includes more stringent compliance programs for companies in various sectors of the life sciences industry with which we may need to comply and enhanced penalties for non-compliance with the new health care regulations. Complying with new regulations may divert management resources, and inadvertent failure to comply with new regulations may result in penalties being imposed on us.

Some states and localities have established drug importation programs for their citizens, and federal drug import legislation has been introduced in Congress. The Medicare Prescription Drug Plan legislation, which became law in December 2003, required the Secretary of Health and Human Services to promulgate regulations for drug reimportation from Canada into the United States under some circumstances, including when the drugs are sold at a lower price than in the United States. The Secretary, however, retained the discretion not to implement a

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drug reimportation plan if he finds that the benefits do not outweigh the costs, and has so far declined to approve a reimportation plan. Proponents of drug reimportation may attempt to pass legislation that would directly allow reimportation under certain circumstances. Legislation or regulations allowing the reimportation of drugs, if enacted, could decrease the price we receive for any products that we may develop and adversely affect our future revenues and prospects for profitability.

If our new management team is not effective or if we fail to attract, hire and retain qualified personnel, we may not be able to design, develop, market or sell our products or successfully manage our business.

Our business prospects are dependent on our management team. The loss of Dr. Ahn, our President and Chief Executive Officer, or our other executive officers, or our inability to identify, attract, retain and integrate additional qualified key personnel, could make it difficult for us to manage our business successfully and achieve our business objectives.

Competition for skilled research, product development, regulatory and technical personnel also is intense, and we may not be able to recruit and retain the personnel we need. The loss of the services of any key research, product development, regulatory, and technical personnel, or our inability to hire new personnel with the requisite skills, could restrict our ability to develop our product candidates.

We use biological and hazardous materials, and we may be liable for any contamination or injury we cause.

Our research and development activities involve the controlled use of potentially harmful biological materials as well as hazardous materials, chemicals and various radioactive compounds. We cannot completely eliminate the risk of accidental contamination or injury; we may be liable for any damages that result, and any liability could exceed our resources.

We are also subject to numerous environmental, health and workplace safety laws and regulations, including those governing laboratory procedures, exposure to blood-borne pathogens and the handling of biohazardous materials. We maintain workers’ compensation insurance to cover us for costs and expenses we may incur due to injuries to our employees resulting from the use of these materials. State laws mandate the limits of our workers’ compensation insurance, and our workers’ compensation liability is capped at these state-mandated limits. We do not maintain insurance for environmental liability or toxic tort claims that may be asserted against us in connection with our storage or disposal of biological, hazardous or radioactive materials. Additional federal, state and local laws and regulations affecting our operations may be adopted in the future. We may incur substantial costs to comply with, and substantial fines or penalties if we violate any of these laws or regulations.

Risks Relating To Our Financial Position and Capital Requirements

We may not be able to obtain sufficient financing, and may not be able to develop our product candidates.

We believe that our existing cash, cash equivalents and other working capital should be sufficient to fund our operations through at least the second quarter of 2014. This projection is based on our current planned operations and is subject to changes in our plans and uncertainties inherent in our business, and we may need to seek to replenish our existing cash and cash equivalents sooner than we project. In the future, we will be dependent on obtaining further financing from third parties in order to maintain our operations and to meet our financial obligations. We cannot assure that additional funding to maintain our operations and to meet our obligations to our licensors will be available to us in the future on acceptable terms, or at all. If we fail to obtain additional funding when needed, we would be forced to scale back, or terminate, our operations, or to seek to merge with or to be acquired by another company.

We anticipate that we will need to raise substantial amounts of money to fund a variety of future activities integral to the development of our business, which may include but are not limited to the following:

We cannot assure you that any financing needed for the development of our business will be available to us on acceptable terms or at all. If we cannot obtain additional financing in the future, our operations may be restricted and we may ultimately be unable to continue to develop and potentially commercialize our product candidates.

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We expect to continue to incur significant research and development expenses, which may make it difficult for us to attain profitability, and may lead to uncertainty about or as to our ability to continue as a going concern.

Substantial funds were expended to develop our technologies and product candidates, and additional substantial funds will be required for further preclinical testing and clinical trials of our product candidates, and to manufacture and market any products that are approved for commercial sale. Because the successful development of our products is uncertain, we are unable to precisely estimate the actual funds we will require to develop and potentially commercialize them. In addition, we may not be able to generate enough revenue, even if we are able to commercialize any of our product candidates, to become profitable.

In the event that we are unable to achieve or sustain profitability or to secure additional financing, we may not be able to meet our obligations as they come due, raising substantial doubts as to our ability to continue as a going concern. Any such inability to continue as a going concern may result in our common stock holders losing their entire investment. There is no guaranty that we will become profitable or secure additional financing. Our financial statements contemplate that we will continue as a going concern and do not contain any adjustments that might result if we were unable to continue as a going concern. Changes in our operating plans, our existing and anticipated working capital needs, the acceleration or modification of our expansion plans, increased expenses, potential acquisitions or other events will all affect our ability to continue as a going concern. Future financing may be obtained through, and future development efforts may be paid for by, the issuance of debt or equity, which may have an adverse effect on our security holders or may otherwise adversely affect our business.

If we raise funds through the issuance of debt or equity, any debt securities or preferred stock issued will have rights, preferences and privileges senior to those of holders of our common stock in the event of a liquidation. In such event, there is a possibility that once all senior claims are settled, there may be no assets remaining to pay out to the holders of common stock. In addition, if we raise funds through the issuance of additional equity, whether through private placements or additional public offerings, such an issuance would dilute your ownership in us.

The terms of debt securities may also impose restrictions on our operations, which may include limiting our ability to incur additional indebtedness, to pay dividends on or repurchase our capital stock, or to make certain acquisitions or investments. In addition, we may be subject to covenants requiring us to satisfy certain financial tests and ratios, and our ability to satisfy such covenants may be affected by events outside of our control.

You may have difficulty evaluating our business, because we have a limited history and our historical financial information may not be representative of our future results.

We have limited operating experience and may not be able to effectively operate.

We are a development-stage company with limited operating history conducting oncology drug programs. We will focus on developing and, if we obtain regulatory approval, commercializing our product candidates, and there is no assurance that we will be successful. There is no assurance that we will be able to manage our business effectively, or that we will be able to identify, hire and retain any needed additional management or scientific personnel to develop and implement our product development plans, obtain third-party contracts or any needed financing or achieve our other business objectives.

We may be unable to comply with our reporting and other requirements under federal securities laws.

As a publicly traded company, we are subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, or the “ Exchange Act ,” and the Sarbanes-Oxley Act of 2002, or the “ Sarbanes-Oxley Act .” In addition, the Exchange Act requires that we file annual, quarterly and current reports. Our failure to prepare and disclose this information in a timely manner could subject us to penalties under federal securities laws, expose us to lawsuits and restrict our ability to access financing. The Sarbanes-Oxley Act requires that we, among other things, establish and maintain effective internal controls and procedures for financial reporting. From time to time we evaluate our existing internal controls in light of the standards adopted by the Public company Accounting Oversight Board. It is possible that we or our independent registered public accounting firm may identify significant deficiencies or material weaknesses in our internal control over financial reporting in the future. Any failure or difficulties in implementing and maintaining these controls could cause us to fail to meet the periodic reporting obligations or result in material misstatements in our financial statements.

Section 404 of the Sarbanes-Oxley Act requires annual management assessments of the effectiveness of our internal control over financial reporting. Our failure to satisfy the requirements of Section 404 on a timely basis could result in the loss of investor confidence in the reliability of our financial statements, which in turn could have a material adverse effect on our business and our common stock.

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We have no control over RXi.

We currently own approximately 33 million shares of common stock of RXi, or approximately 10% of the outstanding RXi common shares, but have no control over RXi’s management or operations. RXi has its own board of directors and management, who are responsible for the affairs and policies of RXi and its development plans. The directors, management and other security holders of RXi may have interests that are different from ours, and RXi may engage in actions in connection with its business and operations that we believe are not in our best interests. We have agreed with RXi not to sell or dispose of any of our RXi shares for a one-year period ending April 27, 2013.

The value of our ownership interest in RXi will depend on RXi’s success in developing and commercializing products developed based upon its RNAi technologies, which activities are subject to significant risks and uncertainties described in RXi’s filings with the SEC, and there may not be a market to sell our RXi shares at the trading price, if at all.

Risks Relating to Ownership of Our Common Stock

The market price and trading volume of our common stock may be volatile.

The market price of our common stock has exhibited substantial volatility recently. Between January 1, 2012 and December 31, 2012, the sale price of our common stock as reported on The NASDAQ Capital Market ranged from a low of $0.43 to a high of $3.54. The market price of our common stock could continue to fluctuate significantly for many reasons, including the following factors:

In addition, factors beyond our control may also have an impact on the price of our stock. For example, to the extent that other large companies within our industry experience declines in their stock price, our stock price may decline as well. In addition, when the market price of a company’s common stock drops significantly, security holders often institute securities class action lawsuits against the company. A lawsuit against us could cause us to incur substantial costs and could divert the time and attention of our management and other resources.

In conjunction with our acquisition of Apthera, we issued to the former Apthera shareholders contingent value rights entitling them to future payments of a total of up to $32 million of contingent consideration based on the achievement of specified development and commercial milestones relating to NeuVax™. In February 2012, we issued at a price per share of $0.76 to the holders of contingent value rights a total of 1,315,789 shares of our common stock in payment of the first $1 million of contingent consideration. At our option, we may make future payments of the contingent consideration, if and when due, including $1 million expected to become due in 2013, in either cash or in shares of our common stock valued for this purpose at the market price of our common stock when the contingent consideration becomes payable. We may determine to pay contingent consideration in shares of our common stock rather than cash, depending upon our cash and cash requirements, the market price of our common stock at the time and other relevant factors. To the extent we pay any future contingent consideration in shares of our common stock, it would have a dilutive effect on our stockholders.

To the extent we choose to pay any contingent consideration in shares of our common stock, we will be obliged to file a registration statement with the SEC covering the resale of such shares by the contingent value rights holders. We cannot predict if future issuances or sales of our common stock issued to our contingent value rights holders, or the availability of our common stock for issuance or sale, will harm the market price of our common stock or our ability to raise capital.

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Future sales of substantial amounts of our common stock, or the possibility that such sales could occur, could adversely affect the market price of our common stock.

Substantial issuances or sales of our common stock, including shares offered hereby or shares issued upon exercise of our outstanding options, in the public market, or the perception by the market that these issuances or sales could occur, could lower the market price of our common stock or make it difficult for us to raise additional capital. As of March 11, 2013, we had 83,067,652 shares of common stock issued and outstanding. Substantially all of these shares are available for public sale, subject in some cases to volume and other limitations or delivery of a prospectus.

As of March 11, 2013, we had reserved for issuance 9,372,283 shares of our common stock issuable upon the exercise of outstanding stock options at a weighted-average exercise price of $2.25 per share. Subject to applicable vesting requirements, upon exercise of these options, the underlying shares may be resold into the public market. In the case of outstanding options that have exercise prices that are below the market price of our common stock from time to time, our stockholders would experience dilution.

We cannot predict if future issuances or sales of our common stock issued to our contingent value rights holders, or the availability of our common stock for issuance or sale, will harm the market price of our common stock or our ability to raise capital.

Our warrants may result in dilution to our stockholders.

Our March 2011 and April 2011 warrants to purchase a total of 3,207,000 shares of common stock at a current exercise price of $0.65 per share contain so-called full-ratchet anti-dilution provisions. Our March 2010 and December 2012 warrants to purchase a total of 7,938,000 shares of common stock at current exercise prices of $2.20 per share and $1.90 per share, respectively, contain so-called weighted-average anti-dilution provisions. These anti-dilution provisions will be triggered upon an issuance by us of shares of our common stock or common stock equivalents at a price per share below the then-exercise price of the warrants, subject to some exceptions.

To the extent that these anti-dilution provisions are triggered in the future, we would be required to reduce the exercise price of all the warrants on either a full-ratchet or weighted-average basis, which would have a dilutive effect on our stockholders at the time.

We may issue preferred stock in the future, and the terms of the preferred stock may reduce the value of our common stock.

We are authorized to issue up to 5,000,000 shares of preferred stock in one or more series. Our board of directors may determine the terms of future preferred stock offerings without further action by our stockholders. If we issue preferred stock, it could affect your rights or reduce the market value of our outstanding common stock. In particular, specific rights granted to future holders of preferred stock may include voting rights, preferences as to dividends and liquidation, conversion and redemption rights, sinking fund provisions, and restrictions on our ability to merge with or sell our assets to a third party.

We have never declared or paid cash dividends on our capital stock and we do not anticipate paying cash dividends in the foreseeable future.

Our business requires significant funding. We currently plan to invest all available funds and future earnings in the development and growth of our business and do not anticipate paying any cash dividends on our common stock in the foreseeable future. As a result, capital appreciation, if any, of our common stock will be our stockholders’ sole source of potential gain for the foreseeable future.

Anti-takeover provisions of our certificate of incorporation and by-laws and provisions of Delaware law could delay or prevent a change of control that you may favor.

Anti-takeover provisions of our certificate of incorporation and by-laws and provisions of Delaware law may discourage, delay or prevent a merger or other change of control that security holders may consider favorable, or may impede the ability of the holders of our common stock to change our management. These provisions of our certificate of incorporation and by-laws, among other things:

In addition, Section 203 of the Delaware General Corporation Law provides that, subject to limited exceptions, persons that acquire, or are affiliated with a person that acquires, more than 15% of the outstanding voting stock of a Delaware corporation such as our company shall not engage in any business combination with that corporation, including by merger, consolidation or acquisitions of additional shares for a three-year period following the date on which that person or its affiliate crosses the 15% stock ownership threshold. Section 203 could operate to delay or prevent a change of control of our company.

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