VioQuest Pharmaceuticals issued new U.S. patent for Lenocta

VioQuest Pharmaceuticals today announced that the United States Patent and Trademark Office has issued the first patent for the company's investigational product candidate Lenocta (sodium stibogluconate). U.S. Patent No. 7,416,723 entitled "Therapeutic compositions and methods useful in modulating protein tyrosine phosphatases," encompasses novel compositions including Lenocta for the treatment of cancer and a broad range of other diseases.

"Based on Lenocta's demonstrated anti-tumor activity against melanoma, renal cancer, prostate cancer, leukemia, and other cancers both alone and in combination with other approved immune-activation agents, including IL-2 and interferons, we believe this product candidate represents a promising approach to treating cancer," said Michael D. Becker, president and chief executive officer of VioQuest Pharmaceuticals. "We are also enthusiastic about the new FDA priority review voucher program, which could enable us to accelerate development and commercialization efforts for Lenocta in the treatment of leishmaniasis."

Pentavalent antimonial compounds such as Lenocta are considered as a first-line treatment for leishmaniasis, a protozoan infection usually found in tropic and sub-tropic countries. The pharmacological mechanism of action for pentavalent antimonials in treating leishmaniasis is not fully understood, but research has indicated that the therapeutic effect might be mediated via cellular targets. Researchers at The Cleveland Clinic recently discovered that Lenocta inhibits specific protein tyrosine phosphatases, which are relevant in the treatment of cancer and other diseases.

VioQuest Pharmaceuticals licensed rights to sodium stibogluconate from the Cleveland Clinic Foundation and is developing the drug as a protein tyrosine phosphatase inhibitor for a range of potential indications. According to the results of both preclinical and clinical trials:

• Lenocta has marked and broad anti-tumor activity in vivo as a single agent at a dosage that may be clinically achievable and well tolerated;
• The demonstrated synergy between Lenocta and various cytokine therapies in vivo indicates that combination therapy with Lenocta could significantly improve efficacy of current cytokine therapies in cancer treatment; and
• Because Lenocta inhibits certain protein tyrosine phosphatases with a distinct mechanism of action, it may be useful as an alternative therapeutic for cancers that are non-responsive or resistant to conventional therapies.
• Lenocta is in a Phase 2a clinical trial as a potential treatment for melanoma, renal cell carcinoma, and other solid tumors. For information about the study, please visit http://www.clinicaltrials.gov/ and use the search term "NCT00629200." The clinical status was recently updated at the 2008 ASCO annual meeting in an oral presentation by Dr. Aung Naing from MD Anderson.

VioQuest Pharmaceuticals is planning to utilize historical published data and an observational study of approximately 400 U.S. Army patients to support a New Drug Application (NDA) for Lenocta. The approval of this NDA could position VioQuest Pharmaceuticals to receive a priority review voucher offered through the recently enacted Food and Drug Administration Amendments Act of 2007 (Section 524 to the Federal Food, Drug and Cosmetic Act or FFDCA). Designed to encourage the development of treatments for tropical diseases, a priority review voucher will be awarded to a sponsor upon approval of a tropical disease product application. A tropical disease product application is a new chemical entity human drug application that is itself deemed eligible for priority review under the preexisting priority review criteria and is approved for use in the prevention, detection, or treatment of a tropical disease. A priority review voucher may be redeemed for priority six-month review of one new drug application submitted under Section 505(b)(1) of the FFDCA or one biologics license application submitted under Section 351 of the Public Health Services Act that would otherwise be reviewed under FDA's standard 10-month review clock. The FDA's new priority review voucher program is scheduled to go into effect in September of 2008.

Lenocta (sodium stibogluconate) is a selective, small molecule inhibitor of certain protein tyrosine phosphatases (PTPs), such as SHP-1, SHP-2 and PTP1B, with demonstrated anti-tumor activity against a wide spectrum of cancers both alone and in combination with other approved immune activation agents, including IL-2 and interferons. PTPs are a family of proteins that regulate signal transduction pathways in cells and have been implicated in a number of diseases including cancer, diabetes, and neurodegeneration.

In addition to its potential role as a cancer therapeutic, sodium stibogluconate has been approved in many countries around the world as a first-line treatment of leishmaniasis, an infection typically found in tropic and sub-tropic developing countries. Historical published data and a large observational study conducted by the U.S. Army, including data from approximately 400 patients, will support a New Drug Application for Lenocta with the FDA. Lenocta has been granted Orphan Drug status for leishmaniasis.

VioQuest Pharmaceuticals is a New Jersey-based biotechnology company dedicated to becoming a recognized leader in the successful development of novel drug therapies targeting both the molecular basis of cancer and side effects of treatment. VioQuest's oncology portfolio includes: Xyfid (1% uracil topical) for the treatment of dry skin conditions and manage the burning and itching associated with various dermatoses; VQD-002 (triciribine phosphate monohydrate), a targeted inhibitor of Akt activation; and Lenocta™ (sodium stibogluconate), an inhibitor of certain protein tyrosine phosphatases such as SHP-1, SHP-2, and PTP1B.