SciClone Pharmaceuticals, Inc.: SciClone Reaches Agreement With FDA on Special Protocol Assessment for Phase 3 Thymalfasin Tria
FOSTER CITY, CA--(Marketwire - November 17, 2008) - SciClone Pharmaceuticals, Inc. (
Based on the FDA's review, the agency agrees that the design and planned analysis of SciClone's study adequately addresses the objectives necessary to support a regulatory submission.
"Patients suffering from stage IV melanoma have very few treatment options available. Based on the positive data from an earlier phase 2 trial, thymalfasin could provide new treatment modalities for this high unmet medical need," said Israel Rios, MD, SciClone's Chief Medical Officer. "The FDA's acceptance of our phase 3 protocol for thymalfasin for the treatment of stage IV melanoma, the most advanced form of skin cancer, is a critical step in the advancement of this clinical program. We are now able to chart the best course going forward, which may include bringing on a development partner."
In June 2007, SciClone announced that its thymalfasin (ZADAXIN®, thymosin alpha 1) achieved its primary endpoint in a phase 2 clinical trial treating patients diagnosed with stage IV melanoma. Results showed that thymalfasin in combination with dacarbazine (DTIC) chemotherapy tripled the overall response rate and extended overall survival by nearly 3 months compared to patients treated with DTIC, the current standard of care, combined with interferon alpha.
The phase 2 multi-center, randomized open-label study enrolled 488 patients with stage IV melanoma at 64 European clinical sites. The trial was designed to evaluate different dose levels of thymalfasin in combination with DTIC chemotherapy, with and without low-dose interferon alpha, as a first-line treatment for stage IV melanoma. Most patients enrolled in the trial had liver and other metastases and the remaining patients had lung metastases and skin or lymph node metastases. Thymalfasin at all dose levels was well-tolerated in all treated patients, with no serious adverse events attributed to the drug. For more information on this phase 2 trial, please refer to SciClone's press release dated June 4, 2007.
How Thymalfasin Works in Melanoma
Suppression of the growth of immune-sensitive tumors such as melanoma have been shown to be dependent on a strong immune response, including a large number of activated effectors such as tumor-infiltrating lymphocyte cells (TILs) and specific anti-melanoma cytotoxic T lymphocytes (CTL). It is also important to increase the presentation of cancer-specific antigens to the immune system through sustained expression of these molecules along with MHC Class I, as cancers avoid the immune system by decreases in this presentation. Thymalfasin's potential beneficial role in treatment of melanoma derives from its demonstrated activation of these various arms of the immune system, including increases in TILs, CTLs, and expression of MHC Class I and tumor-specific antigens. Thymalfasin's multiple activities arise through activation of Toll-like receptor 9 and signaling through increases in the nuclear factor NfKB through Myd88 and IKKb. Evaluation of thymalfasin's utility in melanoma animal models has confirmed effective anti-tumor activity.
About Melanoma
Skin cancer is the most common form of cancer in the United States. In 2008, the American Cancer Society estimates that approximately 8,420 deaths will occur from melanoma and another 62,480 cases of melanoma are expected to be diagnosed in this country. Melanoma is classified as stage IV, the most advanced form, once the cancer has spread beyond the skin to a distant site. DTIC and interleukin-2 (IL-2) are the only FDA-approved therapies for the treatment of stage IV melanoma. However, neither of these therapeutic agents nor alpha interferon, used alone or in combination, are effective at extending overall patient survival, which at this stage is typically only about six to nine months. Response to treatment largely depends upon the stage of melanoma, disease site and the extent to which the cancer has spread.
ZADAXIN received Orphan Drug designation in the United States for stage IIb through stage IV melanoma in March 2006.
About SciClone
SciClone Pharmaceuticals, Inc. (
The information in this press release contains forward-looking statements including our expectations and beliefs regarding financial results for 2008, future sales and operations, and the timing 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. In addition, statements that refer to expectations, goals, projections or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. These statements are not guarantees of future performance and are subject to risks, uncertainties and assumptions that are difficult to predict and actual results could differ materially and adversely. These risks include changes in demand for and sales of ZADAXIN, the progress or failure of clinical trials, our actual experience in executing on our objectives, the performance of our partners, maintenance of the sufficiency and eligibility of the enrolled patient population, unanticipated delays or additional expenses incurred during our clinical trials, our future cash requirements, delays in analyzing and synthesizing data obtained from clinical trials, the performance and future actions of our strategic partners, unexpected delays in clinical trial enrollment, future actions by the U.S. Food and Drug Administration or equivalent regulatory authorities in Europe and the fact that experimental data and clinical results derived 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.