Press Release: SciClone Acquires Clinical-Stage Pancreatic Cancer Compound

SciClone Acquires Clinical-Stage Pancreatic Cancer Compound SAN MATEO, CA -- April 26, 2007 -- SciClone Pharmaceuticals, Inc. (NASDAQ: SCLN) today announced that it has acquired the exclusive rights in the United States and Canada to develop and commercialize RP101, a clinical-stage compound for the treatment of cancer. SciClone acquired the rights from Resistys, Inc., a wholly owned subsidiary of Avantogen Oncology, Inc. In a previous phase 1 clinical trial evaluating RP101 in combination with gemcitabine, the current standard of care, to treat late-stage pancreatic cancer patients, the median survival for the RP101 treated group was 9.3 months, compared to the historical control of approximately 6 months for patients treated with gemcitabine alone. "In-licensing RP 101 advances our corporate strategy to build a product portfolio of candidates for the treatment of cancer and other significant unmet medical needs," commented Friedhelm Blobel, Ph.D., President and Chief Executive Officer of SciClone Pharmaceuticals, Inc. "Our goal is to initiate a U.S. phase 2 study using RP101 to treat late-stage pancreatic cancer by the fourth quarter of 2007." Manuel Hidalgo, M.D., Ph.D., Director of Gastrointestinal Oncology at Johns Hopkins University and Chairman of the Pancreatic Cancer Research Team, an organization of international researchers focused on accelerating the development of new treatments for pancreatic cancer added, "The PCRT is enthusiastic about moving forward in partnership with SciClone for the development of RP101 in a robust double-blind, placebo controlled, phase 2 clinical trial evaluating this promising drug candidate's safety and efficacy for the treatment of stage IV pancreatic cancer patients." Under the terms of the agreement, SciClone acquired the exclusive rights in the United States and Canada to develop and commercialize RP101 for the treatment of cancer from Resistys, Inc. SciClone will pay approximately $1.7 million in upfront fees, a $1.3 million milestone payment upon initiation of a phase 2 clinical trial, post phase 3 success-based regulatory and commercial payments up to $22 million, and royalties on future sales to Avantogen Oncology, Inc. and RESprotect GmbH. SciClone will initially develop RP101 in combination with gemcitabine for the treatment of pancreatic cancer. About Pancreatic Cancer Pancreatic cancer is one of the most deadly forms of cancer. The American Cancer Society estimates that in 2007, approximately 37,170 new cases and 33,370 deaths will result from pancreatic cancer in the United States, making it the fourth leading cause of overall cancer death. This disease is difficult to diagnose in its early stages, and most patients have incurable disease by the time they are diagnosed with pancreatic cancer. The overall median survival of patients with pancreatic cancer is only four to six months. Patients with advanced stages of pancreatic cancer are typically treated with chemotherapeutic agents such as gemcitabine, alone or in combination with other therapeutics, with minimal increases in overall survival. About RP101 RP101 is a nucleoside analog which has been evaluated in preclinical and clinical studies for its potential to prevent induction of chemoresistance and enhance chemosensitivity. RP101 has been shown to induce cell death, or apoptosis, and suppresses the expression of genes associated with drug resistance. RP101 has shown biological activity in preclinical and clinical studies for various cancer indications. RP101's potential efficacy for treating cancer patients was discovered by RESprotect GmbH. RP101, also known as BVdU, has been evaluated in combination with cytotoxic agents such as gemcitabine which is used to treat pancreatic, lung, ovarian and breast cancer patients. Although approved in several European countries for antiviral indications, RP101's potential efficacy to combat chemoresistance and improve chemosensitivity constitutes a new clinical use for RP101 which is protected by use patents. In a clinical study evaluating 22 late-stage pancreatic cancer patients treated with increasing doses of RP101 in combination with fixed doses of gemcitabine, median survival for the treated group was 9.3 months, compared to a historical control of approximately 6 months for patients treated with gemcitabine alone. Additionally, six and 12-month survival rates for treated patients were 68% and 39%, respectively, compared to historical controls of 47% and 13% for patients treated with gemcitabine alone. In a separate phase 1 study published in the Journal of Clinical Oncology, patients treated with RP101, gemcitabine and cisplatin had a median survival of 447 days, compared to the historical control of 186 days for patients treated with gemcitabine and cisplatin alone. Median time to progression for the treated patient group was 280 days compared to 104 for the historical control group. In both clinical trials, the most common adverse events were nausea, fatigue, vomiting, neutropenia, anorexia, and fever, toxicities consistent with those expected for gemcitabine alone. Although it is difficult to draw conclusions from two separate, unrelated trials, SciClone believes the results from these clinical trials are encouraging. About SciClone SciClone Pharmaceuticals is a biopharmaceutical company engaged in the development of therapeutics to treat life-threatening diseases. SciClone's lead product ZADAXIN® is currently being evaluated in late-stage clinical trials for the treatment of malignant melanoma and hepatitis C. ZADAXIN is approved for sale in select markets internationally, most notably in China where SciClone has an established sales and marketing operation. A key part of SciClone's strategy is to leverage its advantage in China by in-licensing or acquiring the marketing rights to other products, such as the DC Bead, to broaden its portfolio in this rapidly growing pharmaceutical market. SciClone's other drug development candidate is SCV-07, currently in early clinical development in the U.S. for the treatment of viral infectious diseases. For more information about SciClone, visit www.sciclone.com. The information in this press release contains forward-looking statements including our expectations and beliefs regarding progress and results of our clinical trials. Words such as "expects," "plans," "believe," "may," "will," "anticipated," "intended" and variations of these words or similar expressions are intended to identify forward-looking statements. These statements are not guarantees of future performance and are subject to risks, uncertainties and assumptions that are difficult to predict. Therefore, our actual results could differ materially and adversely from those expressed in any forward-looking statements as a result of various factors, including the progress of ongoing and proposed trials and studies for RP101, unexpected adverse results to patients, future actions by the U.S. Food and Drug Administration or equivalent regulatory authorities in China and Europe and the fact that experimental data and clinical results derived from pre-clinical studies or from studies with a limited group of patients may not be predictive of the results of larger studies, as well as other risks and uncertainties described in SciClone's filings with the Securities and Exchange Commission.