Biopharmaceuticals Oncology Acquisitions

 News Release - July 31, 2006

Receptor BioLogix Acquires Late-Stage Cancer Drug from Aphton Corp.

Insegia(TM) Immunotherapeutic for Pancreatic and Stomach Cancers

SOUTH SAN FRANCISCO, Calif., July 31 (HSMN NewsFeed) -- Receptor BioLogix, Inc., a privately held biopharmaceutical company focused on development of cancer drugs, announced today that it has acquired the cancer vaccine Insegia(TM), and related assets, from Philadelphia-based Aphton Corp. (Pink Sheet: APHTQ) in a Chapter 11 bankruptcy sale that was recently approved by the U.S. Bankruptcy Court for the District of Delaware. The transaction is expected to close within 30 days, subject to certain conditions, including delivery of specified assets and related technology associated with Insegia. Financial details were not disclosed.

Insegia, also known as G17DT, is a therapeutic cancer vaccine that has been extensively studied for its effects on cancers of gastrointestinal (GI) origin. The immunotherapeutic stimulates the body to produce antibodies that neutralize the peptide hormone, gastrin. Normally involved in the stimulation of gastric acid secretion for digestion, gastrin is a potent growth factor for GI malignancies, including stomach cancer and pancreatic cancer -- two of the most deadly forms of cancer, neither of which have satisfactory treatments. Two Phase III clinical trials of Insegia have been completed in patients with advanced pancreatic cancer, and multiple Phase II trials have been undertaken in patients with stomach cancer, which have shown promising results.

"Insegia has been clinically studied in very difficult forms of cancer," said Thomas A. Glaze, CEO of Receptor BioLogix. "In view of the promising clinical trial results to date, we believe there is a strong likelihood Insegia has a beneficial effect on these cancers and warrants further clinical development. In addition, the available mechanisms for expedited regulatory approval in the United States and Europe will be pursued."

According to Michael Shepard, Ph.D., Receptor BioLogix's chief scientific officer, the company is well positioned to further develop Insegia. "We have assembled a team of manufacturing, regulatory and clinical trial experts who will focus on the design and execution of additional clinical studies that may be required for the drug's market approval. Insegia will become the most advanced product in our growing portfolio of growth factor receptor antagonists to treat cancer and other diseases. It fits very well with our product development programs, especially because a principal mechanism of gastrin tumor promotion is likely mediated through a member of the EGF receptor family, an area of focus for our company."

About Insegia

According to the American Cancer Society, each year more than 250,000 Americans are diagnosed with some form of GI cancers, which are the leading cause of cancer mortality worldwide. The dismal survival of patients, especially those with pancreatic cancer, is caused by the late diagnosis and low surgical resection rates. In pancreatic cancer, median survival is 8-12 months for patients with locally advanced unresectable disease, and only 3-6 months for those who present with metastases. The Insegia therapeutic vaccine exemplifies the potential role immunotherapy may have in the management of these cancers.

Insegia is comprised of a synthetic peptide derived from gastrin (G17), bound to an inactive form of the diphtheria toxin (DT), which together elicit a powerful immune response against gastrin. The therapeutic has potentially wide applicability since gastrin is associated with several tumor types. Clinical studies to date have shown Insegia to be generally safe and promising for the treatment of GI cancers alone or in combination with chemotherapy, although further Phase III testing is required to support regulatory approval. [For a review, see Clinical experiences with G17DT in gastrointestinal malignancies. Expert Rev Anticancer Ther. 2006 Apr; 6(4):487-92. See also An open-label, multinational, multicenter study of G17DT vaccination combined with cisplatin and 5-fluorouracil in patients with untreated, advanced gastric or gastroesophageal cancer: the GC4 study. Cancer. 2006 May 1;106(9):1908-16.]

About Receptor BioLogix

Receptor BioLogix Inc., based in South San Francisco, Calif., is focused on developing the first broad-spectrum anti-HER therapeutic, resulting from its program to commercialize a newly discovered class of protein therapeutics called Intron Fusion Proteins(TM) (IFP(TM)) to treat cancer, autoimmune, metabolic and other diseases. The company has identified a protein that blocks intracellular signaling triggered by members of the epidermal growth factor (EGF) receptor family, including the HER-2 receptor that is abnormally expressed in some 30 percent of breast cancer patients. In contrast to other drugs that target this family, preclinical studies have shown that it downregulates multiple members of the HER family of receptors - HER-1 (EGFR), HER-2, and HER-3. For more information, visit the company's web site at http://www.rblx.com .

Source: Receptor BioLogix

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