Molecular Insight Pharmaceuticals, Inc. Advances Azedra Program Into Pivotal Phase 2 Therapeutic Trial in Neuroendocrine Cancer Patients

CAMBRIDGE, MA--(Marketwire - August 7, 2009) - Molecular Insight Pharmaceuticals, Inc. MIPI today announced that it has initiated a pivotal Phase 2 clinical trial for AzedraT (UltratraceT Iobenguane I 131), its lead oncology candidate for the treatment of malignant pheochromocytoma, a type of neuroendocrine cancer. The single-arm trial will evaluate the efficacy and safety of Azedra in adult patients with malignant relapsed/refractory pheochromocytoma and position Molecular Insight to file a New Drug Application (NDA).

Azedra has been designated as an Orphan Drug with Fast Track status by the U.S. Food and Drug Administration.

Pheochromocytoma tumors are usually found in the adrenal glands, but may arise in other areas of the body. For malignant pheochromocytoma, radiation therapy offers short-term symptomatic relief, but no cure. Chemotherapy trials have failed to produce cures or significant remissions. For patients with this malignant disease, for whom surgery is not an option, the five-year survival rate is less than 50 percent.

Azedra is a targeted radiotherapeutic, which consists of the known iobenguane I 131 molecule (commonly known as I-131-MIBG) radiolabeled using the Company's proprietary Ultratrace technology. If successful, Azedra would be the first anti-cancer therapy in the United States indicated for the treatment of pheochromocytoma. Molecular Insight also is developing Azedra for the treatment of neuroblastoma, a type of neuroendocrine cancer in children.

Daniel L. Peters, President and Chief Executive Officer of Molecular Insight, said, "The launch of this trial marks a significant milestone for our Azedra program, which addresses the clear need for new treatment options for pheochromocytoma. Azedra is a promising candidate. This targeted radiotherapeutic demonstrated high tumor uptake in preclinical studies and favorable pharmacokinetics in completed trials. Azedra's development underscores Molecular Insight's commitment to apply innovative approaches to address unmet patient needs."

In March 2009, Molecular Insight received Special Protocal Assessment approval from the U.S. Federal Drug Administration (FDA) for the Phase 2 trial. Azedra trial IB-12B will be conducted in 58 adults (evaluable) with pheochromocytoma with an expected enrollment of about 75.

Pheochromocytoma tumors cause excess release of the hormones epinephrine and norepinephrine, producing adverse and often severe effects on a patient's heart rate and blood pressure. The primary endpoint of the study will be Azedra's ability to reduce the need for anti-hypertensive medications required to treat the elevated blood pressure often seen as a key sign of the cancer. This trial has begun at centers in the United States and ultimately will include sites in Western Europe.

John W. Babich, Ph.D., Molecular Insight's Executive Vice President, Chief Scientific Officer and President of Research and Development, said, "Molecular Insight is combining an already commercialized molecule with our proprietary Ultratrace radiolabeling technology. We believe that the Ultratrace technology platform enables us to maximize the therapeutic value of Azedra by eliminating unnecessary cold contaminants, or non-radioactive iobenguane, which provide no therapeutic benefit. The absence of cold contaminants allows greater tumor concentration of Azedra and reduced side effects related to the drug's administration."

MDS Nordion to Supply Azedra

Molecular Insight also announced that it has contracted with MDS Nordion, Ottawa, Ontario, Canada, to manufacture and supply Azedra for late-stage clinical trials and, upon FDA approval, for commercial use. A section of MDS Nordion's existing Ottawa facility will be dedicated to the manufacture of Azedra and designed to comply with FDA and European Medicines Agency requirements for the aseptic manufacture of radiopharmaceuticals.

About Azedra

Azedra recognizes a unique molecular target over-expressed on the surface of certain neuroendocrine cancer cells, which enables the drug to be accumulated selectively by the tumor. Azedra, developed using Molecular Insight's proprietary Ultratrace technology, is designed to maximize the delivery of iobenguane I 131 molecules to targeted neuroendocrine tumors and to enable safe and effective treatment while minimizing the amount of non-radioactive iobenguane molecules administered to the patient. Azedra is based on iobenguane I 131, a radiotherapeutic currently marketed in Europe for treating several types of neuroendocrine cancers.

Azedra is one of two clinical-stage oncology candidates that Molecular Insight is developing for the treatment of neuroendocrine tumors. The Company also is developing OnaltaT (90Y-edotreotide), a radiolabeled somatostatin analog, initially for the treatment of pancreatic neuroendocrine and carcinoid tumors whose symptoms are not controlled by conventional somatostatin analog therapy.

About Molecular Insight Pharmaceuticals, Inc.

Molecular Insight Pharmaceuticals MIPI is a Cambridge, Massachusetts-based biopharmaceutical company focused on the discovery and development of innovative radiopharmaceuticals in the emerging field of molecular medicine. These novel radiopharmaceuticals will provide important improvements in disease detection and enable the delivery of radiation therapy to widespread metastatic cancers. The Company has focused the initial applications of its proprietary technologies in the areas of cardiology and oncology. Molecular Insight's lead molecular imaging radiopharmaceutical product candidate, ZemivaT, is being developed for the diagnosis of cardiac ischemia, or insufficient blood flow to the heart. The Company's imaging candidate, TrofexT, is in development for the detection of metastatic prostate cancer. Molecular Insight's lead molecular radiotherapeutic product candidates, AzedraT, OnaltaT, and SolazedT, are being developed for detection and treatment of cancer. In addition, the Company's discovery efforts continue to identify early-stage candidates -- a product of its in-house scientific expertise and the application of its proprietary platform technologies. For more information, visit http://www.molecularinsight.com.

Forward-Looking Statements

Statements in this release that are not strictly historical in nature constitute "forward-looking statements." Such statements include, but are not limited to, statements about the development of AzedraT, Onalta™, Zemiva™, Trofex™, SolazedT and our other product candidates. Such forward-looking statements involve known and unknown risks, uncertainties, and other factors that may cause the actual results of Molecular Insight to be materially different from historical results or from any results expressed or implied by such forward-looking statements. These factors include, but are not limited to, risks and uncertainties related to the progress, timing, cost, and results of clinical trials and product development programs; difficulties or delays in obtaining regulatory approval for product candidates; competition from other pharmaceutical or biotechnology companies; and the additional risks discussed in filings with the Securities and Exchange Commission (SEC). The Company's SEC filings are available through the SEC's Electronic Data Gathering Analysis and Retrieval system (EDGAR) at www.sec.gov. Press releases for Molecular Insight Pharmaceuticals, Inc. are available on our website: www.molecularinsight.com. If you would like to receive press releases via e-mail, please contact: investor@molecularinsight.com. All forward-looking statements are qualified in their entirety by this cautionary statement, and Molecular Insight undertakes no obligation to revise or update this release to reflect events or circumstances after the date hereof.