62 Drug development is a highly uncertain undertaking and involves a substantial degree of risk. We have never generated any revenue from product sales, and we may never generate revenue or be profitable. We have no products approved for commercial sale and have not generated any revenue from product sales. We do not anticipate generating any revenue from product sales until after we have successfully completed clinical development and received regulatory approval for the commercial sale of a product candidate, if ever. Our ability to generate revenue and achieve profitability depends significantly on many factors, including: • successfully completing research and preclinical and clinical development of our product candidates; • obtaining regulatory approvals and marketing authorizations for product candidates for which we successfully complete clinical development and clinical trials; • developing a sustainable and scalable manufacturing process for our product candidates, as well as establishing and maintaining commercially viable supply relationships with third parties that can provide adequate products and services to support clinical activities and any commercial demand for our product candidates; • identifying, assessing, acquiring and/or developing new product candidates; • negotiating favorable terms in any collaboration, licensing or other arrangements into which we may enter; • launching and successfully commercializing product candidates for which we obtain regulatory and marketing approval, either by collaborating with a partner or, if launched independently, by establishing a sales, marketing and distribution infrastructure; • obtaining and maintaining an adequate price for our product candidates, both in the United States and in foreign countries where our products are commercialized; • obtaining adequate reimbursement for our product candidates from payors; • obtaining market acceptance of our product candidates as viable treatment options; • addressing any competing technological and market developments; • maintaining, protecting, expanding and enforcing our portfolio of intellectual property rights, including patents, trade secrets and know-how; and • attracting, hiring and retaining qualified personnel. Because of the numerous risks and uncertainties associated with drug development, we are unable to predict the timing or amount of our expenses, or when we will be able to generate any meaningful revenue or achieve or maintain profitability, if ever. In addition, our expenses could increase beyond our current expectations if we are required by the FDA or foreign regulatory agencies, to perform studies in addition to those that we currently anticipate, or if there are any delays in any of our or our future collaborators’ clinical trials or the development of any of our product candidates. Even if one or more of our product candidates is approved for commercial sale, we anticipate incurring significant costs associated with commercializing any approved product candidate and ongoing compliance efforts.