SOURCE: SciClone Pharmaceuticals, Inc.

June 04, 2007 06:32 ET

SciClone's SCV-07 Inhibits Melanoma Tumor Growth in Animal Model Study

Abstract in Proceedings of Annual Meeting of the American Society of Clinical Oncology

SAN MATEO, CA--(Marketwire - June 4, 2007) - SciClone Pharmaceuticals, Inc. (NASDAQ: SCLN) today reported data showing that SCV-07 inhibits the growth of melanoma tumors in an animal model study. These data were the subject of an abstract accepted for the Annual Meeting of the American Society of Clinical Oncology in Chicago, Illinois.

"These animal model data demonstrate SCV-07's therapeutic activity and potential to inhibit the growth of melanoma tumors," commented Cynthia Tuthill, Ph.D., Senior Vice President of Scientific Affairs and Chief Scientific Officer of SciClone Pharmaceuticals, Inc. "While we expect to initiate a phase 2 clinical trial using SCV-07 to treat a viral disease in June of this year, we are encouraged by the prospect of SCV-07 as a candidate for cancer therapy as we believe it is critical to explore the range of potential applications for this unique molecule."

Animal Model Data

In this study, mice inoculated with melanoma tumor were randomized into six treatment groups: four which received escalating doses of SCV-07 and two control groups. The treatment groups received SCV-07 via subcutaneous injection at doses of 0.01, 0.10, 1.0, or 5.0 mg/kg for 14 consecutive days. One control group received vehicle alone, while the second control group received dacarbazine (DTIC) chemotherapy, via subcutaneous injection at a dose of 50 mg/kg once daily for 14 consecutive days. DTIC is the current standard of care for malignant melanoma and is very effective in inhibiting tumor growth in the B16 animal model but does not increase median survival in humans beyond the standard six to nine months. Tumor size (by caliper) and body weights were measured once every 3 days throughout the study.

After treatment ended on day 15 of the study, mice treated with SCV-07 at the higher doses of 1.0 mg/kg and 5.0 mg/kg showed the greatest inhibition of tumor growth with decreases of 16.5% and 30.2%, respectively, versus the control group treated with DTIC which achieved a 95.1% response as expected. While SCV-07 was not as strong as DTIC in slowing growth, it is important to note that the resistance and toxicity seen with DTIC in treatment of humans may not be seen with SCV-07, which acts through an immune stimulating mechanism.

                                     % Inhibition of Tumor
                                     Growth Versus Control Group
Treatment Arm                        (Day 15, End of Treatment)

Vehicle (negative control)           continuous tumor growth
DTIC (50 mg/kg) (positive control)   95.1
SCV-07 (5.0 mg/kg)                   30.2
SCV-07 (1.0 mg/kg)                   16.5
SCV-07 (0.10 mg/kg)                   7.9
SCV-07 (0.01 mg/kg)                  15.3
How SCV-07 Works in Melanoma

SciClone's proprietary drug candidate SCV-07 (gamma-D-glutamyl-L-tryptophan) is a synthetic peptide with proven immune stimulating effects. SCV-07 has shown efficacy in treating various viral and bacterial infections. Several cancers, including melanoma, are known to be sensitive to immune modulation, and therefore it was of interest to determine if treatment with a compound such as SCV-07 would demonstrate efficacy against the tumor. The stimulating effects of SCV-07 on T helper cells and macrophages could lead to increases in tumor-infiltrating lymphocytes and anti-melanoma cytotoxic T cells, immune cells that have been shown to correlate with survival in subjects with melanoma.

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 and broaden its portfolio in the rapidly growing Chinese market by in-licensing or acquiring the marketing rights to other products, such as DC Bead™. For the U.S. market, SciClone's clinical-stage drug development candidates are SCV-07 for the treatment of viral infectious diseases and RP101 for the treatment of pancreatic cancer. For more information about SciClone, visit www.sciclone.com.

This press release contains forward-looking statements including our statement regarding timing and expectations for an SCV-07 Phase 2 clinical trial and because the experimental or clinical data described may imply certain actual results in larger patient populations. These statements are subject to risks and uncertainties and may. Actual outcomes may differ from our forward-looking statements because of the inherent uncertainties in the timing of clinical trial events including patient enrollment. Experimental data and clinical results derived from studies with animals or a limited group of patients may not be predictive of the results of larger studies and, therefore, such experimental or clinical data is not necessarily predictive of efficacy or safety or the results of larger studies and clinical trials.

Contact Information

  • Corporate contact:

    Richard Waldron
    Executive Vice President and Chief Financial Officer
    SciClone Pharmaceuticals, Inc.
    650-358-3437