Molecular Insight Pharmaceuticals, Inc. (NASDAQ: MIPI - News) announced today that it has initiated a Phase 2a clinical trial of Azedra (Ultratrace™ iobenguane I-131 or Ultratrace MIBG) for the treatment of children with high-risk neuroblastoma, a neuroendocrine cancer that primarily affects children. Azedra is already being evaluated in an ongoing dose-ranging clinical trial for pheochromocytoma in adults. Azedra is a targeted radiotherapeutic comprised of the known I-131 MIBG molecule radiolabeled using Molecular Insight’s proprietary Ultratrace technology, which removes unnecessary nonradioactive molecules, or cold contaminants, to maximize therapeutic potential.

The primary objective of the trial is to determine the maximum tolerated dose (MTD) of Azedra in children with neuroblastoma. Secondary goals are to determine tumor and dose responses; determine toxicity; estimate normal organ dosimetry; and describe the effect of Azedra therapy on overall quality of life. The Molecular Insight trial is being coordinated by the New Approaches to Neuroblastoma Therapy (NANT) Consortium, a group of 14 universities and Children’s Hospitals with strong research and treatment programs for neuroblastoma.

“This important Azedra trial in children with neuroblastoma underscores our full commitment to develop small molecule, targeted radiotherapeutics that address significant unmet needs in cancers affecting both adults and children,” said David S. Barlow, Chairman and Chief Executive Officer of Molecular Insight. “Along with our ongoing Azedra dose-ranging clinical trial in adults with pheochromocytoma, we are developing several other targeted radiotherapeutics to treat and detect cancer, including OnaltaTM, which complements Azedra, for the treatment of neuroendocrine tumors; SolazedTM for the treatment of malignant melanoma; and TrofexTM for the detection and staging of metastatic prostate cancer.”

“Neuroblastoma is an aggressive and difficult to treat form of neuroendocrine cancer that usually affects children under five years of age,” said Katherine Matthay, M.D., Chief of Pediatric Hematology and Oncology at the University of California San Francisco Children’s Medical Center. “Unfortunately, the prognosis for many of these children is quite poor. There currently are no FDA-approved treatments available for patients who have progressive, recurrent or refractory disease, and our current treatment options are extremely limited.” Dr. Matthay is chairing the study for the NANT Consortium.

“This trial is the first to assess Azedra’s activity in neuroblastoma patients as part of our larger program to evaluate its therapeutic potential in multiple types of neuroendocrine cancer,” said John W. Babich, Ph.D., President and Chief Scientific Officer of Molecular Insight. “While traditional I-131 MIBG has demonstrated clinical activity in neuroblastoma in the past, it contains cold contaminants that compete with the active radiotherapeutic molecules binding to receptor sites on tumor cells. Our preclinical studies have shown that Azedra, produced with our proprietary Ultratrace technology, enables the highest proportion of MIBG molecules to be radiolabeled, significantly increasing the amount of radiolabeled MIBG uptake in the tumor and reducing the potential for side effects due to cold contaminants.”

During the trial, approximately 24 patients across NANT’s 14 member sites will be scanned using an imaging dose of Azedra to determine if the imaging dose demonstrates normal MIBG biodistribution and tumor uptake. Cohorts of three to six patients will then receive one therapeutic dose of Azedra within 28 days of the MIBG biodistribution and tumor uptake scan. Disease and final toxicity evaluation will be performed approximately 60 days post therapy, as will a quality of life assessment.

Azedra is a small molecule, targeted radiotherapeutic based on the known I-131 MIBG molecule produced with Molecular Insight’s proprietary Ultratrace technology. MIBG binds to the norepinephrine transporter, a protein that is highly expressed on neuroendocrine tumors such as neuroblastoma. Azedra has the potential to maximize the amount of radiation delivered to the tumor cell, improving tumor kill while reducing side effects. Azedra has received both Orphan Drug and Fast Track designations from the U.S. Food and Drug Administration.

About Neuroblastoma

Neuroblastoma is a type of neuroendocrine cancer that primarily affects children. It develops in approximately one in every 7,000 live births and is the most common solid tumor in children outside of the brain. Neuroblastoma originates in the adrenal medulla or other sites of the sympathetic nervous system and most often begins during early childhood, usually in children younger than five years. It sometimes forms before birth but is usually found later, when the tumor begins to grow and cause symptoms. By the time neuroblastoma is diagnosed, the cancer has usually spread, most often to the lymph nodes, bones, bone marrow, liver and skin. The clinical behavior of neuroblastoma is highly variable, with some tumors being easily treatable, but approximately 50% of the tumors are very aggressive and can be categorized as high-risk. Each year about 600 children in the United States will develop neuroblastoma.

About The NANT Consortium
The New Approaches to Neuroblastoma (NANT) consortium, led by Dr. Katherine Matthay, is a group of 14 universities and Children’s Hospitals in the United States of America and Canada with strong research and treatment programs for neuroblastoma. Working closely together, they test promising new therapies for high-risk and relapsed neuroblastoma. NANT links laboratory and clinical investigators to develop novel therapies for high-risk neuroblastoma. NANT conducts clinical trials that test new drugs and new combinations of drugs against high-risk neuroblastoma. Those with promising results will then be considered for more extensive national testing. The majority of funding for NANT comes from a peer reviewed Program Project Grant that is funded by the National Cancer Institute. Dr. Robert C. Seeger, Director of the Cancer Research Program at Childrens Hospital Los Angeles, is the Principal Investigator.

About Molecular Insight Pharmaceuticals, Inc.

Molecular Insight Pharmaceuticals (NASDAQ: MIPI - News) is the leading biopharmaceutical company specializing in the emerging field of molecular medicine, applying innovations in the identification and targeting of disease at the molecular level to improve healthcare for patients with life-threatening diseases. The company is focused on discovering, developing and commercializing innovative, targeted radiotherapeutics and molecular imaging pharmaceuticals with initial applications in the areas of oncology and cardiology. Its lead targeted radiotherapeutic product candidates, Azedra and Onalta, are being developed for detection and treatment of cancer. The company’s lead molecular imaging pharmaceutical product candidate, Zemiva, is being developed for the diagnosis of cardiac ischemia, or insufficient blood flow to the heart. In addition, the company has a growing pipeline of product candidates resulting from application of its proprietary platform technologies to new and existing compounds. Molecular Insight Pharmaceuticals is based in Cambridge, Massachusetts.

Forward-Looking Statements
Statements in this release that are not strictly historical in nature constitute “forward-looking statements.” Such statements may include, without limitation, statements with respect to the Company’s plans, objectives, expectations and intentions and other statements identified by words such as “may,” “could,” “would,” “should,” “believes,” “expects,” “anticipates,” “estimates,” “intends,” “plans” or similar expressions. Examples of such statements include, but are not limited to, the number of patients that will be scanned during the trials, the number of patients that will receive a therapeutic dose of Azedra within 28 days of the MIBG biodistribution and tumor uptake scan, the timing when disease and final toxicity evaluation will be performed, statements regarding potential uses of Azedra or Ultratrace, other statements regarding product candidates, product development programs, the U.S. FDA, or the clinical trial process or its outcomes. 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. All forward-looking statements are qualified in their entirety by this cautionary statement, and Molecular Insight undertakes no obligation to revise or update this news release to reflect events or circumstances after the date hereof.