RISK FACTORS

        Before you invest in our common stock, you should understand the high degree of risk involved. You should consider carefully the description of those risks set forth below as well as the other information in this prospectus, including the historical financial statements and related notes, before you decide to purchase shares of our common stock. If any of the following risks actually occurs, our business, financial condition and operating results could be adversely affected. As a result, the trading price of our common stock could decline and you could lose part or all of your investment.

Risks Related To Our Business

We have a history of operating losses and may not achieve or sustain profitability.

        We have incurred losses in each year since our inception and expect to experience losses over the next several years. As of March 31, 2006, we had an accumulated deficit of $147.7 million. These losses resulted principally from costs incurred in our research and development programs and from our general and administrative expenses. These losses, among other things, have had and will continue to have an adverse effect on our stockholders' equity, total assets and working capital.

        We expect to continue to incur significant operating expenses and anticipate that our expenses and losses will increase in the foreseeable future as we seek to:

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complete our Phase II and III clinical trials for Prochymal;



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complete our Phase I/II clinical trial for Chondrogen and, if supported by the Phase I/II clinical trial, initiate additional clinical trials;



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complete our Phase I clinical trial for Provacel and, if supported by the Phase I clinical trial, initiate Phase II clinical trials;



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maintain and expand our network of sales professionals for the distribution of Osteocel, and further expand and train our sales network in anticipation of the approval of our biologic drug candidates for commercial sale;



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expand our manufacturing capacity, which will require that we obtain additional administrative and manufacturing space and build-out a portion of that space as a Food and Drug Administration, or FDA, compliant and validated product manufacturing facility;



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relocate some or all of our business operations to a newly leased facility;



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maintain, expand and protect our intellectual property portfolio;



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hire additional clinical, quality control, scientific and management personnel; and



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add operational, financial, accounting, facilities engineering and information systems personnel, consistent with expanding our operations and our status as a public company.

        In addition, Osteocel is our only commercially available product. While revenue from Osteocel has increased since its commercial introduction in July 2005, our ability to scale up our production capabilities for commercial quantities of this product are limited, and our costs in marketing and distributing this product will also increase as production increases.

        The extent of our future operating losses or profits is highly uncertain, and we may not achieve or sustain profitability. If we are unable to achieve and then maintain profitability, the

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market value of our common stock will decline and you could lose part or all of your investment.

We may not be able to raise additional capital necessary to fund our operations.

        Our future capital requirements will depend on many factors, including:

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the level of cash flows from Osteocel sales;



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the scope and results of our research and preclinical development programs;



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the scope and results of our clinical trials, particularly regarding the number of patients required for our Phase III trial for Prochymal;



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the timing of and the costs involved in obtaining regulatory approvals for our biologic drug candidates, which could be more lengthy or complex than obtaining approval for a new conventional drug, given the FDA's limited experience with late-stage clinical trials and marketing approval for stem cell therapeutics;



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the costs of building and operating our manufacturing facilities, both in the near term to support Osteocel sales and our clinical activities and also in anticipation of expanding our commercialization activities;



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the costs of maintaining, expanding and protecting our intellectual property portfolio, including litigation costs and liabilities;



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the costs of repaying our debt; and



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the costs of enlarging our work force consistent with expanding our business and operations and status as a public company, and as necessary to enhance and train our sales network in anticipation of the approval of our biologic drug candidates for commercial sale.

        As a result of these factors, we may need or choose to seek additional funding prior to our becoming cash flow positive on an operational basis. We would likely seek such funding through public or private financings or some combination of them. Although not our current focus, we might also seek funding through collaborative arrangements if determined to be necessary or appropriate. Additional funding may not be available to us on acceptable terms, or at all. If we obtain capital through collaborative arrangements, these arrangements could require us to relinquish rights to our technologies or biologic drug candidates. If we raise capital through the sale of equity, or securities convertible into equity, dilution to our then existing stockholders would result. If we raise additional capital through the incurrence of debt, we would likely become subject to covenants restricting our business activities, and holders of debt instruments would have rights and privileges senior to those of our equity investors. In addition, servicing the interest and repayment obligations under these borrowings would divert funds that would otherwise be available to support research and development, clinical or commercialization activities.

        If we are unable to obtain adequate financing on a timely basis, we may be required to delay, reduce the scope of or eliminate one or more of our programs, any of which could have a material adverse effect on our business, financial condition and results of operations.

If the potential of our stem cell therapies to treat diseases is not realized, the value of our technology and our development programs could be significantly reduced.

        The potential of our stem cell therapies to treat diseases is currently being explored by us. We have not proven in clinical trials that our stem cell therapy will be a safe and effective

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treatment for any disease. Our stem cell therapies are susceptible to various risks, including undesirable and unintended side effects, unintended immune system responses, inadequate therapeutic efficacy or other characteristics that may prevent or limit their marketing approval or commercial use. We have not treated a sufficient number of patients to allow us to make a determination that serious unintended consequences will not occur. If the potential of our stem cell therapies to treat disease is not realized, the value of our technology and our development programs could be significantly reduced. Because our biologic drug candidates are based on MSCs, any negative developments regarding the therapeutic potential or side effects of MSCs could have a material adverse effect on our business, financial condition and results of operations.

Our product development programs are based on novel technologies and are inherently risky.

        We are subject to the risks of failure inherent in the development of products based on new technologies. The novel nature of our therapeutics creates significant challenges in regards to product development and optimization, manufacturing, government regulation, third-party reimbursement and market acceptance. For example, the FDA has relatively limited experience with stem cell therapies. None has been approved by the FDA for commercial sale, and the pathway to regulatory approval for our biologic drug candidates may accordingly be more complex and lengthy. Additionally, stem cells are subject to donor-to-donor variability, which can make standardization more difficult. As a result, this pathway may be subject to increased uncertainty, as compared to the pathway for new conventional drugs.

There are no FDA approved treatments for some of the disease indications we are pursuing. This could complicate and delay FDA approval of our biologic drug candidates.

        There are no drugs or therapies currently approved with stated indications for the first-line treatment of acute GvHD or the treatment of steroid refractory GvHD. As a result, the clinical efficacy endpoints, or the criteria to measure the intended results of treatment, for our biologic drug candidate Prochymal for the treatment of GvHD may be difficult to determine. In addition, patients battling GvHD and who, therefore, are candidates for treatment with Prochymal, are typically very ill as a result of an underlying genetic or oncologic condition. Due to the graveness of their underlying disease and the very serious complications and disorders that often accompany acute GvHD, many of these patients will die from causes other than GvHD prior to the completion of the study even if their GvHD responds favorably to treatment with Prochymal. The resulting reduction in the number of patients available for evaluation at the end of the study may make it more difficult for us to demonstrate efficacy as necessary to obtain FDA approval to market Prochymal for commercial sale.

        There are also no drugs or therapies currently approved with stated indications for the regeneration of meniscal tissue, or the repair of heart muscle following heart attack. As a result, the clinical endpoints for our biologic drug candidates Chondrogen and Provacel may be difficult to determine. In the case of Prochymal for the treatment of Crohn's Disease, there are other products approved for the treatment of this disease, so it is expected that the clinical efficacy endpoints for Prochymal for this indication will be established by comparison with these already approved treatments. In order to obtain FDA approval for this indication, we will likely have to demonstrate, among other things, that our biologic drug candidate is safe and effective. The results of our clinical trials must be statistically significant, meaning that there must be sufficient data to indicate that it is unlikely the outcome occurred by chance. These challenges may prevent us from developing and commercializing products on a timely or profitable basis, or at all.

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Our biologic drug candidates represent new classes of therapy that the marketplace may not understand or accept.

        Even if we successfully develop and obtain regulatory approval for our biologic drug candidates, the market may not understand or accept them. We are developing biologic drug candidates that represent novel treatments and will compete with a number of more conventional products and therapies manufactured and marketed by others, including major pharmaceutical companies. The degree of market acceptance of any of our developed and potential products will depend on a number of factors, including:

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the clinical safety and effectiveness of Osteocel and our biologic drug candidates and their perceived advantage over alternative treatment methods;



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our ability to demonstrate that Prochymal can have a clinically significant effect on steroid refractory GvHD;



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our ability to differentiate our biologic drug candidates from stem cell drug candidates of other companies derived from human embryonic or fetal tissue, which have given rise to significant ethical controversies;



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ethical controversies that may arise regarding the use of stem cells or human tissue of any kind, including adult stem cells, adult bone marrow and other adult tissues derived from donors, in the manufacture and sale for profit of Osteocel and our biologic drug candidates;



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adverse events involving our biologic drug candidates or the products or product candidates of others that are stem cell based;



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our ability to supply a sufficient amount of our product to meet regular and repeated demand in order to develop a core group of medical professionals familiar with and committed to the use of our products; and



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the cost of our products and the reimbursement policies of government and third-party payors.

        If the health care community does not accept Osteocel or our potential products for any of the foregoing reasons, or for any other reason, it could affect our sales, having a material adverse effect on our business, financial condition and results of operations.

The successful commercialization of our biologic drug candidates, or any of our other potential stem cell therapeutics, will depend on obtaining reimbursement from third-party payors.

        If we successfully develop and obtain necessary regulatory approvals, we intend to sell our biologic drug candidates initially in the United States and Europe. In the United States, the market for any pharmaceutical product is affected by the availability of reimbursement from third-party payors, such as government health administration authorities, private health insurers, health maintenance organizations and pharmacy benefit management companies. Stem cell therapies like Prochymal, Chondrogen and Provacel may be expensive compared with standard pharmaceuticals, due to the higher cost and complexity associated with the research, development and production of stem cell therapies, the small size and large geographic diversity of the target patient population for some indications, and the complexity associated with distribution of stem cell therapies which require special handling and shipment procedures and protocols. This, in turn, may make it more difficult for us to obtain adequate reimbursement from third-party payors, particularly if we cannot demonstrate a favorable cost-benefit relationship. Third-party payors may also deny coverage or offer

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inadequate levels of reimbursement for our potential products if they determine that the product has not received appropriate clearances from the FDA or other government regulators or is experimental, unnecessary or inappropriate. For example, patients battling GvHD and who, therefore, are candidates for treatment with Prochymal, are typically very ill as a result of an underlying genetic or oncologic condition. Because these patients have a low probability of survival, third-party payors may resist reimbursing the cost of treatment.

        In the countries of Europe and in some other countries, the pricing of prescription pharmaceutical products and services and the level of government reimbursement are subject to governmental control. In these countries, pricing negotiations with governmental authorities can take six to 12 months or longer after the receipt of marketing approval for a product. To obtain reimbursement or pricing approval in some countries, we may be required to conduct one or more clinical trials that compares the cost effectiveness of our biologic drug candidates or products to other available therapies. Conducting one or more clinical trials would be expensive and result in delays in commercialization of our products.

        Managing and reducing health care costs has been a general concern of federal and state governments in the United States and of foreign governments. Although we do not believe that any recently enacted or presently proposed legislation should impact our business, we might be subject to future regulations or other cost-control initiatives that materially restrict the price we receive for our products. In addition, third-party payors are increasingly challenging the price and cost-effectiveness of medical products and services, and many limit reimbursement for newly approved health care products. In particular, third-party payors may limit the indications for which they will reimburse patients who use any products that we may develop. Cost control initiatives could decrease the price for products that we may develop, which would result in lower product revenues to us.

Our dependence upon a limited supply of adult marrow-rich bone necessary to produce Osteocel may impact our ability to produce Osteocel on a large scale.

        The production of Osteocel does not involve an expansion of MSCs and is therefore limited by the amount of adult human marrow-rich bone donations that are available to us. Since the introduction of Osteocel into the marketplace in July 2005, we have been unable to obtain quantities of adult human marrow-rich bone sufficient to meet the demand for Osteocel. Specifically, the demand for Osteocel has been five to ten times greater than our ability to supply the product, inhibiting our ability to maximize revenue from Osteocel. Osteocel consists of primary, or unexpanded, MSCs in a matrix of viable cancellous bone. Cancellous bone is the porous and spongy inner structure accounting for approximately 20% of total bone mass. The bone and cells are derived from human organ and tissue donors. We rely on the efforts of not-for-profit donor procurement agencies to educate the public and foster an increased willingness to donate bone tissue. These organizations may not be able to provide us with sufficient amounts of viable cancellous bone to meet present or future demand for Osteocel. Our inability to secure enough viable cancellous bone to meet our Osteocel demands limits our ability to successfully market and drive market acceptance of Osteocel and may limit our potential revenues from Osteocel.

Our dependence upon a limited supply of bone marrow donors may impact our ability to produce sufficient quantities of our biologic drug candidates as necessary to complete our clinical trials, and if our trials are successful, to meet product demand.

        The population of acceptable bone marrow donors is limited to volunteers between the ages of 18 and 32. In addition, potential donors are prescreened for a variety of health conditions and are only allowed to donate bone marrow a total of six times in their lifetime,

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further limiting the total number of potential donors. The amount of bone marrow donated may be insufficient for us to mass produce our biologic drug candidates. Future government regulation or health concerns may also reduce the number of donors or otherwise limit the amount of bone marrow available to us. If we cannot secure quantities of bone marrow sufficient to meet the manufacturing demands for our clinical trials, we might not be able to complete our clinical trials and obtain marketing approval for our biologic drug candidates. Moreover, even if our clinical trials are successful and we obtain marketing approval for our biologic drug candidates, our inability to secure enough bone marrow to meet product demand would limit our potential revenues.

Osteocel and our biologic drug candidates are derived from human tissue and bone marrow sources and therefore have the potential for disease transmission.

        The utilization of donated adult human cancellous bone and bone marrow creates the potential for transmission of communicable disease, including but not limited to human immunodeficiency virus, or HIV, viral hepatitis, syphilis, Creutzfeldt-Jakob disease, or the human form of "mad cow" disease, and other viral, fungal or bacterial pathogens. Although we are required to comply with federal and state regulations intended to prevent communicable disease transmission, and our suppliers of adult human bone and bone marrow are also required to comply with such regulations in connection with their collection, storage and supply to us:

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we or our suppliers may inadvertently or unwittingly fail to comply with such regulations;



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even with compliance, our products might nevertheless be viewed by the public as being associated with transmission of disease; and



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a patient that contracts an infectious disease might assert that the use of our products resulted in disease transmission, even if the patient became infected through another source.

        Any actual or alleged transmission of communicable disease could result in patient claims, litigation, distraction of management's attention and potentially increased expenses. Further, any failure in screening, whether by us or other manufacturers of similar products, could adversely affect our reputation, the support we receive from the medical community and overall demand for our products. As a result, such actions or claims, whether or not directed at us, could have a material adverse effect on our reputation with our customers and our ability to market our products, which could have a material adverse effect on our business, financial condition and results of operations.

We have only limited experience manufacturing Osteocel and our biologic drug candidates. We may not be able to manufacture Osteocel in quantities sufficient to expand our market for the product and may not be able to manufacture our biologic drug candidates in quantities sufficient for later stage clinical studies or for commercial sale.

        We may encounter difficulties in the production of Osteocel and our biologic drug candidates due to our manufacturing capabilities. We have not built commercial-scale manufacturing facilities, and we have limited manufacturing experience with Osteocel and our biologic drug candidates. These difficulties could reduce sales of our products, increase our costs or cause production delays, any of which could damage our reputation and hurt our profitability. Even if we were to obtain access to quantities of adult marrow-rich bone sufficient to allow us otherwise to expand our Osteocel manufacturing capabilities, we may not be able to produce sufficient quantities of the product at an acceptable cost, or at all.

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        If we successfully obtain marketing approval for one of our biologic drug candidates, we may not be able to produce sufficient quantities of the product at an acceptable cost. Commercial-scale production of therapies made from live human mesenchymal stem cells involves production in small batches and strict adherence to complex manufacturing and storage protocols and procedures. Our biologic drug candidates are inherently more difficult to manufacture at commercial-scale than chemical pharmaceuticals, which are manufactured using precise chemical formulations and operational methods.

We use third-party collaborators to help us develop and commercialize our products, and our ability to commercialize such products may be impaired or delayed if collaborations are unsuccessful.

        We have arrangements in place with third-party collaborators as a means to help us with research and development efforts or marketing and distribution. For example:

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we currently sell a large majority of our Osteocel product through a distribution arrangement with Blackstone Medical Inc., which sells this product under the Blackstone brand "Trinity";



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we have a collaboration with Boston Scientific Corporation for cardiovascular applications of our MSC technology; and



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we have a collaboration with JCR Pharmaceuticals Co., Ltd. granting to JCR an exclusive right to Prochymal for the treatment of GvHD in Japan.

        Although we have no current intention to do so, we may enter into additional collaborations in the future. We are dependent upon the success of our current and any future collaborators in performing their responsibilities and their continued cooperation. Our collaborators may not cooperate with us or perform their obligations under our agreements with them. We cannot control the amount and timing of our collaborators' resources that will be devoted to performing their responsibilities under our agreements with them. Our collaborators may choose to pursue alternative technologies in preference to those being developed in collaboration with us. The development and commercialization of our potential products will be delayed if collaborators fail to conduct their responsibilities in a timely manner or if they breach or terminate their collaboration agreements with us. Disputes with our collaborators could result in product development delays, decreased revenues and litigation expenses. In addition, because our products may be marketed under a different brand name by our collaborators, as is the case in our relationship with Blackstone, should the relationship be terminated for any reason, our product recognition could be adversely impacted, affecting our product and potentially causing brand confusion in the market.

We are dependent upon third-party suppliers for services and raw materials needed for the manufacture, and we are dependent upon third parties for the distribution, of Osteocel and our biologic drug candidates. If any of these third parties fail or are unable to perform in a timely manner, our ability to manufacture and deliver will be compromised.

        In order to produce our biologic drug candidates for use in clinical studies, and to produce Osteocel and any other of our biologic drug candidates that may be approved for commercial sale, we require biological media, reagents and other highly specialized materials. This is in addition to the adult marrow-rich bone donations used in the manufacture of Osteocel, and the bone marrow aspirate used in the manufacture of our biologic drug candidates. These items must be manufactured and supplied to us in sufficient quantities and in compliance with current Good Manufacturing Practices, or cGMP. To meet these requirements, we have entered into supply agreements with firms which manufacture these

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components to cGMP standards. Our requirements for these items are expected to increase if and when we transition to the manufacture of commercial quantities of our biologic drug candidates. In addition, as we proceed with our clinical trial efforts, we must be able to demonstrate to the FDA that we can manufacture our biologic drug candidates with consistent characteristics. Accordingly, we are materially dependent on these suppliers for supply of cGMP-grade components of consistent quality. Our ability to complete ongoing clinical trials may be negatively affected in the event that we are forced to seek and validate a replacement source for any of these critical components. If we are not able to obtain adequate supplies of these items of consistent quality from our third-party suppliers, it will also be more difficult to manufacture commercial quantities of Osteocel or any of our current biologic drug candidates that may subsequently be approved for commercial sale.

        In addition, we rely on third parties to distribute Osteocel and, if approved, our biologic drug candidates. Proper shipping and distribution requires compliance with specific storage and shipment procedures. For example, our products must be placed in a freezer within 72 hours of shipment. Failure to comply with these procedures or the occurrence of inadvertent damage to the shipping container will necessitate return and replacement, potentially resulting in additional cost and causing us to fail to meet supply requirements.

Use of third-party manufacturers may increase the risk that we will not have adequate quantities of our biologic drug candidates.

        We have used third-party manufacturers to supply our biologic drug candidates for clinical trials. Reliance on third-party manufacturers entails risks to which we would not be subject if we manufactured such components ourselves, including:

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reliance on the third party for regulatory compliance and quality assurance;



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the possible breach of the manufacturing agreement by the third party; and



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the possible termination or nonrenewal of the agreement by the third party, based on its own business priorities, at a time that is costly or inconvenient for us.

        Our contract manufacturers are subject to all of the risks and uncertainties that we have when we manufacture on our own. Similar to us, they are subject to ongoing, periodic, unannounced inspection by the FDA and corresponding state and foreign agencies or their designees to ensure strict compliance with cGMP regulations and other governmental regulations and corresponding foreign standards. However, we do not control compliance by our contract manufacturers with these regulations and standards. Our present or future manufacturers might not be able to comply with these regulatory requirements. If our third-party manufacturers fail to comply with applicable regulations, the FDA or other regulatory authorities could impose sanctions on us, including fines, injunctions, civil penalties, denial of marketing approval of our biologic drug candidates delays, suspension or withdrawal of approvals, license revocation, seizures or recalls of biologic drug candidates or our other products, operating restrictions and criminal prosecutions. Any of these actions could significantly and adversely affect supplies of our biologic drug candidates or other products and could have a material adverse effect on our business, financial condition and results of operations.

        We recently delivered a notice of termination to the contract manufacturer that we had been using to manufacture our biologic drug candidates under development. As a result, this contract terminates in September 2006. We anticipate either renegotiating our contract with this contract manufacturer or negotiating a new agreement with another contract manufacturer. The transition to a replacement contract manufacturer has additional risks, including those risks associated with the development by the replacement contract

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manufacturer of sufficient levels of expertise in the manufacturing process. If we are unable to renegotiate this agreement or enter into a replacement agreement with another contract manufacturer on reasonable terms and in a timely manner, or if any replacement contract manufacturer is unable to develop sufficient manufacturing expertise in a timely manner, we could experience shortages of clinical trial materials, which would negatively impact our ability to complete our clinical trials and obtain marketing approval for the commercial sale of our biologic drug candidates.

If our processing and storage facility or our clinical manufacturing facilities are damaged or destroyed, our business and prospects would be negatively affected.

        If our processing and storage facility or the equipment in the facility were to be significantly damaged or destroyed, we could suffer a loss of some or all of the stored units of our biologic drug candidates and it would force us to halt our clinical trial processes.

        We have a manufacturing facility located in Baltimore, Maryland at which we produce and store stem cells for our clinical trials and Osteocel prior to sale. If this facility or the equipment in it is significantly damaged or destroyed, we may not be able to quickly or inexpensively replace our manufacturing capacity. This facility is located on the Baltimore harbor, and in September 2003 it was flooded by Hurricane Isabel. This event resulted in a temporary suspension of our manufacturing operations. In the event of another temporary or protracted loss of this facility or equipment, we may be able to transfer manufacturing to a third party, but the shift would likely be expensive, and the timing would depend on availability of third-party resources and the speed with which we could have a new facility comply with the necessary regulatory requirements. Such an event could halt our clinical trials and distribution of Osteocel due to a lack of available product. In addition, we have subleased a portion of our facility which requires approval under our lease. We are seeking approval from our landlord for this sublease.

        We have entered into an agreement to sublease approximately 61,203 square feet of space in Columbia, Maryland beginning August 2006, and plan to begin manufacturing in this facility in early 2007.

        Currently, we maintain insurance coverage totaling $12.3 million against damage to our property and equipment, an additional $4.0 million to cover business interruption and extra expenses, $5.6 million to cover R&D restoration expenses, and $50,000 to cover restoration of valuable papers. If we have underestimated our insurance needs, we will not have sufficient insurance to cover losses above and beyond the limits on our policies.

We have experienced significant management turnover.

        Our current Chief Executive Officer, C. Randal Mills, joined us in July 2004. All of our executive officers have joined us since then. Since 1999, we have experienced significant management turnover. Including interim appointees, we have had six chief executive officers since 1999. The departure of two of these resulted in litigation against us. This lack of management continuity, and the resulting lack of long-term history with our company, could result in operational and administrative inefficiencies and added costs. If we were to experience additional turnover at the executive level, these risks would be exacerbated.

If we are not able to recruit and retain qualified management and scientific personnel, we may fail in developing our technologies and biologic drug candidates.

        Our future success depends to a significant extent on the skills, experience and efforts of the principal members of our scientific, management and sales personnel. These members

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include C. Randal Mills, Ph.D., Harry E. Carmitchel, Cary J. Claiborne and Earl R. Fender. The loss of any or all of these individuals could harm our business and might significantly delay or prevent the achievement of research, development or business objectives. We have entered into employment agreements with Dr. Mills and Messrs. Carmitchel, Claiborne and Fender for an initial term of three years. The existence of an employment agreement does not, however, guarantee retention of these employees, and we may not be able to retain those individuals for the duration of or beyond the end of their respective terms. Except for Dr. Mills and Messrs. Claiborne, Carmitchel and Fender, none of our employees is employed for a specified term. Competition for personnel is intense. We may be unable to retain our current personnel or attract or integrate other qualified management and scientific personnel in the future.

        We also rely from time-to-time on outside advisors who assist us in formulating our research and development and clinical strategy. We may not be able to attract and retain these individuals on acceptable terms which could have a material adverse effect on our business, financial condition and results of operations.

Ethical and other concerns surrounding the use of stem cell therapy or human tissue may negatively affect public perception of us or our products or biologic drug candidates, or may negatively affect regulatory approval of our products or biologic drug candidates, thereby reducing demand for our products and adversely affecting the market price for our common stock.

        The commercial success of Osteocel and our biologic drug candidates will depend in part on general public acceptance of the use of stem cell therapy and donated human tissue for the prevention or treatment of human diseases. The use of embryonic stem cells and fetal tissue for research and stem cell therapy has been the subject of substantial national and international debate regarding related ethical, legal and social issues. In the U.S., for example, federal government funding of embryonic stem cell research has been limited to specifically identified cell lines and is not otherwise available. We do not use embryonic stem cells or fetal tissue, but the public may not be able to, or may fail to, differentiate our use of adult stem cells from the use by others of embryonic stem cells or fetal tissue. This could result in a negative perception of our company or our products or biologic drug candidates.

        We obtain our stem cells from volunteer adult bone marrow donors and we obtain cancellous human bone for the production of Osteocel from non-profit organizations that collect and process human organ and tissue donations. Bone marrow donors receive payment, but payment is not received by either human organ and tissue donors or their surviving family members. Ethical concerns have been raised by some about the use of donated human tissue in a for-profit setting, as we are doing.

        Future adverse events in the field of stem cell therapy or changes in public policy could also result in greater governmental regulation of our products and biologic drug candidates and potential regulatory delays relating to the testing or approval of our biologic drug candidates.

We compete with other companies for funding and product sales. Many of our competitors have greater resources or capabilities than we have, or may already have or succeed in developing better products or in developing products more quickly than we do, and we may not compete successfully with them.

        The pharmaceutical and biotechnology industries are highly competitive. We compete for funding and, if our products become available for commercial sale, we will compete in the market place. For funding, we compete primarily with other companies which, like us, are

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focused on developing novel products or therapies for the treatment of human disease based on stem cells or other novel scientific principles. These include Aastrom Biosciences, Advanced Cell Technology, Athersys, Cellerant Therapeutics, Cognate Therapeutics, Cytori Therapeutics, Gamida Cell, Geron, Mesoblast, MultiCell Technologies, Neuronyx, Theradigm, ViaCell, and StemCells.

        In the marketplace, we compete or may eventually compete with other companies and organizations that are marketing or developing therapies for our targeted disease indications, based on traditional pharmaceutical, medical device or other, non-cellular therapy and technologies. These include: Johnson & Johnson, the manufacturer of Cellect for the repair of bone, which competes with Osteocel; Medtronic and Stryker, the manufacturers of Infuse and OP-1, respectively, which compete with Osteocel; Novartis, the manufacturer of Neoral for the prevention of organ rejection in transplant patients, which would compete with Prochymal for the treatment of GvHD; and Centocor, the manufacturer of Remicade, which would compete with Prochymal for the treatment of Crohn's Disease. In addition to those listed above, we have other potential competitors developing a variety of therapeutics.

        We also face competition in the cell therapy field from academic institutions and governmental agencies. Many of our current and potential competitors have greater financial and human resources than we have, including more experience in research and development and more established sales, marketing and distribution capabilities.

        We anticipate that competition in our industry will increase. In addition, the health care industry is characterized by rapid technological change, resulting in new product introductions and other technological advancements. Our competitors may develop and market products that render our current product or any future product non-competitive or otherwise obsolete.

The use of our stem cell therapies in human subjects may expose us to product liability claims, and we may not be able to obtain adequate insurance.

        We face an inherent risk of product liability claims. Neither Osteocel nor any of our biologic drug candidates has been widely used over an extended period of time, and therefore our safety data are limited. We derive the raw materials for manufacturing Osteocel and our biologic drug candidates from human donor sources, the manufacturing process is complex, and the handling requirements are specific, all of which increase the likelihood of quality failures and subsequent product liability claims. We will need to increase our insurance coverage if and when we begin commercializing our biologic drug candidates. We may not be able to obtain or maintain product liability insurance on acceptable terms with adequate coverage or at all. If we are unable to obtain insurance, or if claims against us substantially exceed our coverage, then our business could be adversely impacted. Whether or not we are ultimately successful in any product liability litigation, such litigation could consume substantial amounts of our financial and managerial resources and could result in:

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significant awards against us;



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substantial litigation costs;



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recall of the product;



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injury to our reputation;



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withdrawal of clinical trial participants; and



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adverse regulatory action.

        Any of these results could have a material adverse effect on our business, financial condition and results of operations.

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Risks Related to Intellectual Property

If our patent position does not adequately protect Osteocel, our biologic drug candidates or any future products, others could compete against us more directly, which would harm our business and have a material adverse effect on our financial condition and results of operations.

        Our success depends, in large part, on our ability to obtain and maintain intellectual property protection for our biologic drug candidates. The patent position of biotechnology companies is generally highly uncertain, involves complex legal and factual questions and has been the subject of much litigation. Neither the U.S. Patent and Trademark Office nor the courts has a consistent policy regarding the breadth of claims allowed or the degree of protection afforded under many biotechnology patents.

        The claims of our existing U.S. patents and those that may issue in the future, or those licensed to us, may not confer on us significant commercial protection against competing products. Third parties may challenge, narrow, invalidate or circumvent any patents we own or may obtain in the future. Our patents on MSC technology, in particular, are quite broad in that they cover mesenchymal stem cells and the therapeutic use thereof. Patents with broad claims tend to be more vulnerable to challenge by other parties than patents with more narrowly written claims. Also, our pending patent applications may not issue, and we may not receive any additional patents. Further, the laws of foreign countries may not protect our intellectual property rights to the same extent as do laws of the United States. Our patents might not contain claims that are sufficiently broad to prevent others from utilizing our technologies. Consequently, our competitors may independently develop competing products that do not infringe our patents or other intellectual property. We have filed a patent application covering the composition of matter and methods of manufacture of our commercially available product, Osteocel. This patent has not yet issued and there can be no assurances that it will ever issue. Osteocel is different from our other biologic drug candidates in that it contains primary, or unexpanded, MSCs in a matrix of cancellous bone. Because we do not have a granted patent specifically directed to Osteocel, and because FDA approval is generally not required for tissue based products like Osteocel, competitors might choose to enter this market and produce a substantially similar product that is not covered by a granted patent, whereby we may not be able to prevent the marketing and sale of any such similar products by others. Should others produce a substantially similar product, we will be subject to increased competition and our potential revenues from Osteocel sales may be limited.

        Because of the extensive time required for development, testing and regulatory review of a potential product, it is possible that, before any of our products can be commercialized, any related patent may expire or remain in force for only a short period following commercialization, thereby reducing any advantages of the patent. For instance, one of our base patents on MSC technology will expire in 2013. To the extent our biologic drug candidates based on that technology are not commercialized significantly ahead of this date, or to the extent we have no other patent protection on such products, those products would not be protected by patents beyond 2013. The background technologies used in the development of our biologic drug candidates are known in the scientific community and it is possible to duplicate the methods we use to create our biologic drug candidates.

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If we are unable to protect the confidentiality of our proprietary information and know-how, our competitive position would be impaired and our business, financial condition and results of operations could be adversely affected.

        A significant amount of our technology, especially regarding manufacturing processes, is unpatented and is maintained by us as trade secrets. In an effort to protect these trade secrets, we require our employees, consultants, collaborators and advisors to execute confidentiality agreements upon the commencement of their relationships with us. These agreements require that all confidential information developed by the individual or made known to the individual by us during the course of the individual's relationship with us be kept confidential and not disclosed to third parties. These agreements, however, may not provide us with adequate protection against improper use or disclosure of confidential information, and these agreements may be breached. For example, a portion of the manufacture of Osteocel is protected by trade secrets. A breach of confidentiality could affect our competitive position. In addition, in some situations, these agreements may conflict with, or be subject to, the rights of third parties with whom our employees, consultants, collaborators or advisors have previous employment or consulting relationships. Also, others may independently develop substantially equivalent proprietary information and techniques or otherwise gain access to our trade secrets.

        Adequate remedies may not exist in the event of unauthorized use or disclosure of our confidential information. The disclosure of our trade secrets would impair our competitive position and could have a material adverse effect on our business, financial condition and results of operations.

If we infringe or are alleged to infringe intellectual property rights of third parties, it will adversely affect our business, financial condition and results of operations.

        Our research, development and commercialization activities, including any biologic drug candidates or products resulting from these activities, may infringe or be claimed to infringe patents owned by third parties and to which we do not hold licenses or other rights. There may be applications that have been filed but not published that, when issued, could be asserted against us. These third parties could bring claims against us that would cause us to incur substantial expenses and, if successful against us, could cause us to pay substantial damages. Further, if a patent infringement suit were brought against us, we could be forced to stop or delay research, development, manufacturing or sales of the product or biologic drug candidate that is the subject of the suit.

        For example, we are aware of patents owned by third parties that are directed toward mesenchymal stem cells and the use thereof. Our preliminary research suggests that our biologic drug candidates, upon commercialization, would not infringe a valid claim of these patents. However, our review of these patents is still at an early stage, and our views are subject to change.

        As a result of patent infringement claims, or in order to avoid potential claims, we may choose or be required to seek a license from the third party. These licenses may not be available on acceptable terms, or at all. Even if we are able to obtain a license, the license would likely obligate us to pay license fees or royalties or both, and the rights granted to us might be nonexclusive, which could result in our competitors gaining access to the same intellectual property. Ultimately, we could be prevented from commercializing a product, or be forced to cease some aspect of our business operations, if, as a result of actual or threatened patent infringement claims, we are unable to enter into licenses on acceptable terms. All of

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the issues described above could also impact our collaborators, which would also impact the success of the collaboration and therefore us.

        There has been substantial litigation and other proceedings regarding patent and other intellectual property rights in the pharmaceutical and biotechnology industries. In addition to infringement claims against us, we may become a party to other patent litigation and other proceedings, including interference proceedings declared by the United States Patent and Trademark Office and opposition proceedings in the European Patent Office, regarding intellectual property rights with respect to our products and technology. For example, the patent that was granted to us in Europe for human mesenchymal stem cells has been opposed in the European Patent Office by two different companies. A hearing date for the opposition has not been set, and the losing party has the right to appeal the initial decision. If we do not prevail in the opposition proceedings, we will not have broad patent protection with respect to mesenchymal stem cells in Europe. The outcome of the proceedings is uncertain at this time. The cost to us of any patent litigation or other proceeding, even if resolved in our favor, could be substantial. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively than we can because of their substantially greater financial resources. Patent litigation and other proceedings may also absorb significant management time. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could have a material adverse effect on our ability to compete in the marketplace and, as a result, on our business, financial condition and results of operations.

We may become involved in lawsuits to protect or enforce our patents or the patents of our collaborators or licensors, which could be expensive and time consuming.

        Competitors may infringe our patents or the patents of our collaborators or licensors. As a result, we may be required to file infringement claims to counter infringement or unauthorized use. This can be expensive, particularly for a company of our size, and time-consuming. In addition, in an infringement proceeding, a court may decide that a patent of ours is not valid or is unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that our patents do not cover its technology. An adverse determination of any litigation or defense proceedings could put one or more of our patents at risk of being invalidated or interpreted narrowly and could put our patent applications at risk of not issuing. We are aware of several companies that are employing mesenchymal stem cell technology in their research and product development efforts. If such companies commercialize such products, there is no assurance that we would have a basis for initiating patent infringement proceedings or that if initiated we would prevail in such proceedings.

        Interference proceedings brought by the U.S. Patent and Trademark Office may be necessary to determine the priority of inventions with respect to our patent applications or those of our collaborators or licensors. Litigation or interference proceedings may fail and, even if successful, may result in substantial costs and distraction to our management. We may not be able, alone or with our collaborators and licensors, to prevent misappropriation of our proprietary rights, particularly in countries where the laws may not protect such rights as fully as in the United States.

        Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. In addition, during the course of this kind of litigation, there could be public announcements of the results of hearings, motions or other interim proceedings or developments. If investors perceive these results to be negative, the market price for our common stock could be significantly harmed.

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Risks Related to Regulatory Approval and Other Government Regulations

If we are not able to successfully develop and commercialize our biologic drug candidates and obtain the necessary regulatory approvals, we may not generate sufficient revenues to continue our business operations.

        In order to generate sales revenue from our biologic drug candidates, we must conduct extensive preclinical studies and clinical trials to demonstrate that our biologic drug candidates are safe and effective and obtain required regulatory approvals. Our early stage biologic drug candidates may fail to perform as we expect. Moreover, our biologic drug candidates in later stages of development may fail to show the desired safety and efficacy traits despite having progressed successfully through preclinical or initial clinical testing. We will need to devote significant additional research and development, financial resources and personnel to develop commercially viable products and obtain the necessary regulatory approvals.

        If our biologic drug candidates do not prove to be safe and efficacious in clinical trials, we will not obtain the required regulatory approvals. If we fail to obtain such approvals, we may not generate sufficient revenues to continue our business operations.

        Finally, even if we obtain regulatory approval of a product, that approval may be subject to limitations on the indicated uses for which it may be marketed. Even after granting regulatory approval, the FDA and regulatory agencies in other countries continue to review and inspect marketed products, manufacturers and manufacturing facilities, which may create additional regulatory burdens. Later discovery of previously unknown problems with a product, manufacturer or facility, may result in restrictions on the product or manufacturer, including a withdrawal of the product from the market. Further, regulatory agencies may establish additional regulations that could prevent or delay regulatory approval of our products.

We cannot market and sell our biologic drug candidates in the United States or in other countries if we fail to obtain the necessary regulatory approvals or licensure.

        We cannot sell our biologic drug candidates until regulatory agencies grant marketing approval, or licensure. The process of obtaining regulatory approval is lengthy, expensive and uncertain. It is likely to take two to four years or more to obtain the required regulatory approvals for our lead stem cell biologic drug candidate, Prochymal, or we may never gain the necessary approvals. Any difficulties that we encounter in obtaining regulatory approval may have a substantial adverse impact on our operations and cause our stock price to decline significantly. Moreover, because our biologic drug candidates are all based on a single platform technology, MSCs, any adverse events in our clinical trials for one of our biologic drug candidates could negatively impact the clinical trials and approval process for our other biologic drug candidates.

        To obtain marketing approvals in the United States for MSC products, for instance, we must, among other requirements, complete carefully controlled and well-designed clinical trials sufficient to demonstrate to the FDA that the biologic drug candidate is safe and effective for each disease for which we seek approval. Several factors could prevent completion or cause significant delay of these trials, including an inability to enroll the required number of patients or failure to demonstrate adequately that MSCs are safe, effective and potent for use in humans. Negative or inconclusive results from or adverse medical events during a clinical trial could cause the clinical trial to be repeated or a program to be terminated, even if other studies or trials relating to the program are successful. The FDA can place a clinical trial on hold if, among other reasons, it finds that patients enrolled in the trial

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are or would be exposed to an unreasonable and significant risk of illness or injury. If safety concerns develop, we or the FDA could stop our trials before completion. Some participants in our MSC clinical trial have experienced serious adverse events, three of which have been determined to be possibly related to MSCs. A serious adverse event is an event that results in significant medical consequences, such as hospitalization, disability or death, and must be reported to the FDA. We cannot assure you that safety concerns regarding MSCs will not develop.

        The pathway to regulatory approval for MSCs may be more complex and lengthy than for approval of a new conventional drug. Similarly, to obtain approval to market our stem cell products outside of the United States, we will need to submit clinical data concerning our products and receive regulatory approval from governmental agencies, which in certain countries includes approval of the price we intend to charge for our product. We may encounter delays or rejections if changes occur in regulatory agency policies during the period in which we develop a biologic drug candidate or during the period required for review of any application for regulatory agency approval. If we are not able to obtain regulatory approvals for use of our biologic drug candidates under development, we will not be able to commercialize such products, and therefore may not be able to generate sufficient revenues to support our business.

If we are not able to conduct our clinical trials properly and on schedule, marketing approval by FDA and other regulatory authorities may be delayed or denied.

        The completion of our clinical trials may be delayed or terminated for many reasons, including, but not limited to, if:

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the FDA does not grant permission to proceed and places the trial on clinical hold;



•

subjects do not enroll in our trials at the rate we expect;



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subjects experience an unacceptable rate or severity of adverse side effects;



•

third-party clinical investigators do not perform our clinical trials on our anticipated schedule or consistent with the clinical trial protocol, Good Clinical Practice and regulatory requirements, or other third parties do not perform data collection and analysis in a timely or accurate manner;



•

inspections of clinical trial sites by the FDA or Institutional Review Boards (IRBs), find regulatory violations that require us to undertake corrective action, suspend or terminate one or more sites, or prohibit us from using some or all of the data in support of our marketing applications; or



•

one or more IRBs suspends or terminates the trial at an investigational site, precludes enrollment of additional subjects, or withdraws its approval of the trial.

        Our development costs will increase if we have material delays in our clinical trials, or if we are required to modify, suspend, terminate or repeat a clinical trial. If we are unable to conduct our clinical trials properly and on schedule, marketing approval may be delayed or denied by FDA.

We may not be able to secure and maintain research institutions to conduct our clinical trials.

        We rely on research institutions to conduct our clinical trials. Specifically, the limited number of bone marrow transplant centers further heightens our dependence on such research institutions for the Phase III Prochymal trial. Our reliance upon research institutions,

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including hospitals and clinics, provides us with less control over the timing and cost of clinical trials and the ability to recruit subjects. If we are unable to reach agreement with suitable research institutions on acceptable terms, or if any resulting agreement is terminated, we may be unable to quickly replace the research institution with another qualified institution on acceptable terms. We may not be able to secure and maintain suitable research institutions to conduct our clinical trials.

Final marketing approval of our biologic drug candidates by the FDA or other regulatory authorities for commercial use may be delayed, limited, or prevented, any of which would adversely affect our ability to generate operating revenues.

        Any of the following factors may serve to delay, limit or prevent final marketing approval for our biologic drug candidates;

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our biologic drug candidates require significant clinical testing to demonstrate safety and effectiveness before applications for marketing approval can be filed with the FDA;



•

data obtained from preclinical and nonclinical animal testing and clinical trials can be interpreted in different ways, and the FDA may not agree with our interpretations;



•

it may take many years to complete the testing of our biologic drug candidates, and failure can occur at any stage of the process;



•

negative or inconclusive results or adverse side effects during a clinical trial could cause us to delay or terminate development efforts for a biologic drug candidate; and



•

commercialization may be delayed if the FDA requires us to expand the size and scope of the clinical trials.

        We may experience such delays in the future.

Should the FDA decide that Osteocel does not meet the appropriate regulatory requirements, we will be required to stop production, which will have a material adverse effect on our business, financial condition and results of operations.

        The FDA has developed a tiered, risk-based regulatory framework, which includes criteria for facility management, quality assurance, donor selection, and processing of human cells, tissues, and cellular and tissue based products. We believe that commercial sale of Osteocel does not require pre-market approval by the FDA because we determined that it met the regulatory definition of human cells, tissue, and cellular and tissue-based products, or HCT/Ps. However, should the FDA decide that Osteocel does not meet the regulatory definition of HCT/Ps, we will not be able to produce and sell Osteocel until we obtain FDA approval, which could take years to obtain and which could have a material adverse effect on our business, financial condition and results of operations.

Producing and marketing an approved drug or other medical product is subject to significant and costly post-approval regulation.

        It is likely that Prochymal, if approved based on our currently contemplated Phase III trial, will receive conditional approval by the FDA, and we will be required to conduct Phase IV clinical trials to obtain full approval. Even if we obtain full approval of a product, that approval is subject to limitations on the indicated uses for which we can market it. After granting marketing approval, the FDA and regulatory agencies in other countries continue to review and inspect marketed products, manufacturers and manufacturing facilities, creating additional regulatory burdens. Later discovery of previously unknown problems with a product,

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manufacturer or facility may result in restrictions on the product or manufacturer, including a withdrawal of the product from the market. Further, regulatory agencies may establish additional regulations that could prevent or delay marketing approval of our products.

Our business involves the use of hazardous materials that could expose us to environmental and other liability.

        We have facilities in Maryland that are subject to various local, state and federal laws and regulations relating to safe working conditions, laboratory and manufacturing practices, the experimental use of animals and the use and disposal of hazardous or potentially hazardous substances, including chemicals, micro-organisms and various radioactive compounds used in connection with our research and development activities. In the United States, these laws include the Occupational Safety and Health Act, the Toxic Test Substances Control Act and the Resource Conservation and Recovery Act. We cannot assure you that accidental contamination or injury to our employees and third parties from hazardous materials will not occur. We do not have insurance to cover claims arising from our use and disposal of these hazardous substances other than limited clean-up expense coverage for environmental contamination due to an otherwise insured peril, such as fire.

We may not be able to obtain or maintain Orphan Drug designation for our biologic drug candidates.

        Some jurisdictions, including Europe and the United States, may designate drugs for relatively small patient populations as orphan drugs. Although the FDA has designated Prochymal for the treatment of steroid refractory GvHD as an orphan drug, none of our other biologic drug candidates have received such designation. Orphan Drug designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process, but does make the product eligible for orphan drug exclusivity, reduced filing fees and specific tax credits. Generally, if a company receives the first marketing approval for a product with an Orphan Drug designation in the clinical indication for which it has such designation, the product is entitled to orphan drug exclusivity. Orphan drug exclusivity means that the FDA will not approve another application to market the same drug for the same indication, except in limited circumstances, for a period of seven years in the United States. This exclusivity, however, could block the approval of our biologic drug candidates if a competitor obtains marketing approval before us. Even if we obtain orphan drug exclusivity for any of our biologic drug candidates, we may not be able to maintain it. For example, if a competitive product is shown to be clinically superior to our product, any orphan drug exclusivity we have will not block the approval of such competitive product.

The Fast Track designation for development of any of our products may not lead to a faster development or regulatory review or approval process, and it does not increase the likelihood the biologic drug candidate will receive marketing approval.

        If a drug is intended for the treatment of a serious or life-threatening condition and the drug demonstrates the potential to address unmet medical needs for this condition, the drug sponsor may apply for FDA Fast Track designation for a particular indication. Marketing applications filed by sponsors of products in Fast Track development may qualify for priority review under the policies and procedures offered by the FDA, but the Fast Track designation does not assure any such qualification. Although we have obtained a Fast Track designation from the FDA for Prochymal for the treatment of GvHD, receipt of Fast Track designation may not result in a faster development process, review or approval compared to drugs considered for approval under conventional FDA procedures. In addition, the FDA may withdraw our Fast

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Track designation at any time. If we lose our Fast Track designation, the approval process may be delayed. In addition, our Fast Track designation does not guarantee that we will qualify for or be able to take advantage of the expedited review procedures and does not increase the likelihood that Prochymal will receive regulatory approval for the treatment of steroid refractory GvHD.

Risks Related to this Offering

There has been no prior market for our common stock, and it may trade at prices below the initial public offering price.

        Prior to this offering, there has been no public market for our common stock. We cannot predict the extent to which a trading market for our common stock will develop or be sustained after this offering. The initial public offering price will be determined by negotiations between us and the representative of the underwriters based on factors that may not be indicative of future performance, and may not bear any relationship to the price at which our common stock will trade upon completion of this offering. You may be unable to sell your shares of common stock at or above the initial public offering price.

The trading price of the shares of our common stock could be highly volatile, and purchasers of our common stock could incur substantial losses.

        Our stock price is likely to be volatile. The stock market in general and the market for biotechnology companies in particular have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. As a result of this volatility, investors may not be able to sell their common stock at or above the initial public offering price. The market price for our common stock may be influenced by many factors, including:

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results of clinical trials of our biologic drug candidates or those of our competitors;



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regulatory developments in the United States and foreign countries;



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variations in our financial results or those of companies that are perceived to be similar to us;



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changes in the structure of healthcare payment systems;



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announcements by us of significant acquisitions, strategic partnerships, joint ventures or capital commitments;



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market conditions in the pharmaceutical and biotechnology sectors and issuance of securities analysts' reports or recommendations;



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sales of substantial amounts of our stock by existing stockholders;



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sales of our stock by insiders and 5% stockholders;



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general economic, industry and market conditions;



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additions or departures of key personnel;



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intellectual property, product liability or other litigation against us;



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expiration or termination of our relationships with our collaborators; and



•

the other factors described in this "Risk Factors" section.

        In addition, in the past, stockholders have initiated class action lawsuits against biotechnology and pharmaceutical companies following periods of volatility in the market

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prices of these companies' stock. Such litigation, if instituted against us, could cause us to incur substantial costs and divert management's attention and resources, which could have a material adverse effect on our business, financial condition and results of operations.

Purchasers in this offering will suffer immediate dilution and may experience additional dilution in the future.

        If you purchase common stock in this offering, you will pay more for your shares than the amounts paid by existing stockholders for their shares. In addition, the net tangible book value of your shares based upon our actual book value will immediately be less than the offering price you paid. For more information, see the discussion under the caption "Dilution."

The future sale of our common stock could negatively affect our stock price.

        If our existing stockholders sell a large number of shares of common stock, or the public market perceives that existing stockholders might sell shares of common stock, the market price of our common stock could decline significantly. These stockholders may sell their shares of our common stock starting at various times following this offering. We have agreed, under certain circumstances, to register the resale of shares held by our existing stockholders. In addition, we intend to register approximately 6.9 million shares of common stock that are reserved for issuance under our equity compensation plans. Once we register these shares, they can be freely sold in the public market upon issuance, subject to lock-up agreements and restrictions on our affiliates. For more information, see the discussion under the caption "Shares Eligible for Future Sale."

Contract rights may exist that grant third parties preemptive or registration rights.

        Prior to the appointment of our current management, we engaged in numerous financing transactions. In the course of these transactions, we are aware that we have granted to third parties contract rights to, among other things, cause us to sell to them additional equity or other securities or cause us to register the sale of shares previously sold to them. We may have granted similar rights to additional parties that we are not aware of. No one has made any claim against us in this regard, and we do not believe that any such rights are outstanding except to the extent contained in contracts we have filed as exhibits to this registration statement. Nevertheless, if there are other rights that can be proven by third parties to exist, our share capital could be diluted and we could incur additional expenses, and the market for our stock could be more volatile or depressed because of sales of stock pursuant to these rights.

Concentration of ownership of our common stock among our existing executive officers, directors and principal stockholders may prevent new investors from influencing significant corporate decisions.

        Upon completion of this offering, our executive officers, directors and beneficial owners of 5% or more of our common stock and their affiliates will, in aggregate, beneficially own approximately             % of our outstanding common stock, after giving effect to the conversion of all outstanding shares of our convertible preferred stock into shares of our common stock and the conversion of $                        of our convertible notes into           shares of our common stock (assuming a public offering price of $       per share), but assuming no exercise of the underwriters' over-allotment option and no exercise of outstanding options or warrants. These persons, acting together, will be able to significantly influence all matters requiring stockholder approval, including the election and removal of directors and any merger or other significant corporate transactions. The interests of this group of stockholders

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may not coincide with our interests or the interests of other stockholders. For more information, see the discussion under the caption "Principal Stockholders."

        In addition, Peter Friedli, our Chairman of the Board of Directors, beneficially owned approximately 55% of our outstanding common stock as of June 15, 2006. Accordingly, Mr. Friedli currently has, and will continue to have, a significant influence over the outcome of all corporate actions requiring stockholder approval. For example, since our certificate of incorporation does not provide our stockholders with cumulative voting rights, Mr. Friedli, acting with his affiliates, will be able to elect all of our directors. This power to elect directors could be used in ways that benefit Mr. Friedli and his affiliates to the detriment of other stockholders.

Certain provisions of Delaware law and of our charter documents contain provisions that could delay and discourage takeover attempts and any attempts to replace our current management by stockholders.

        Certain provisions of our certificate of incorporation and bylaws, and applicable provisions of Delaware corporate law, may make it more difficult for or prevent a third party from acquiring control of us or changing our Board of Directors and management. These provisions include:

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the ability of our board of directors to issue preferred stock with voting or other rights or preferences;



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the inability of stockholders to act by written consent;



•

a classified Board of Directors with staggered three-year terms;



•

requirements that special meetings of our stockholders may only be called by the chairman of our Board of Directors, upon request of stockholders holding at least 20% of our capital stock issued and outstanding, or upon a resolution adopted by, or an affirmative vote of, a majority of our Board of Directors; and



•

advance notice procedures our stockholders must comply with in order to nominate candidates for election to our Board of Directors or to place stockholders' proposals on the agenda for consideration at meetings of stockholders.

        We will also be afforded the protections of Section 203 of the Delaware General Corporation Law, which will prevent us from engaging in a business combination with a person who acquires at least 15% of our common stock for a period of three years from the date such person acquired such common stock, unless advance board or stockholder approval was obtained.

        Any delay or prevention of a change of control transaction or changes in our Board of Directors or management could deter potential acquirors or prevent the completion of a transaction in which our stockholders could receive a substantial premium over the then current market price for their shares.

Our management has broad discretion over the use of proceeds from this offering and may invest or spend the proceeds in ways with which you do not agree and in ways that may not yield a return.

        Our management will have broad discretion over the use of proceeds from this offering. You may not agree with management's decisions, and our use of the proceeds may not yield any return on your investment in us. The failure of our management to apply the net

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proceeds of this offering effectively could have a material adverse effect on our business, financial condition and results of operations.

We do not expect to pay cash dividends on our common stock in the foreseeable future. As a result, you must rely on stock appreciation for any return on your investment.

        We do not anticipate paying cash dividends on our common stock in the foreseeable future. Any payment of cash dividends will depend upon our financial condition, results of operations, capital requirements and other factors and will be at the discretion of our Board of Directors. Accordingly, you will have to rely on capital appreciation, if any, to earn a return on your investment in our common stock. Furthermore, we may become subject to contractual restrictions or prohibitions on the payment of dividends.

The requirements of being a public company may strain our resources and distract management.

        As a public company, we will be 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, and the related regulations of the SEC, as well as the rules of The NASDAQ National Market. We have not previously been subject to these requirements, and they may place a strain on our systems and resources. The Exchange Act requires that we file annual, quarterly and current reports with respect to our business and financial condition. The Sarbanes-Oxley Act requires that we maintain effective disclosure controls and procedures and internal controls over financial reporting. In order to maintain and improve the effectiveness of our disclosure controls and procedures and internal control over financial reporting, significant resources and management oversight will be required. In addition, we will be required to have our independent public accounting firm attest to and report on management's assessment of the effectiveness of our internal controls over financial reporting. This may divert management's attention from other business concerns, which could have a material adverse effect on our business, financial condition, results of operations and cash flows. Also, we will need to hire additional accounting and financial staff with appropriate public company experience and technical accounting knowledge, and we cannot assure you that we will be able to do so in a timely fashion. If we are unable to conclude that we have effective internal controls over financial reporting or, if our independent auditors are unable to provide us with an attestation and an unqualified report as to the effectiveness of our internal controls over financial reporting, investors could lose confidence in the reliability of our financial statements, and the market price for our common stock could be significantly harmed.

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