Skip to Content

Molecular Insight Pharmaceuticals, Inc. Reports Onalta Tissue Distribution Data Support Clinical Development Program

CAMBRIDGE, Mass.--(BUSINESS WIRE)--June 18, 2008 - Molecular Insight Pharmaceuticals, Inc. (NASDAQ: MIPI) reported on two preclinical studies that demonstrated the potential of indium-111-edotreotide as an imaging tool to predict Onalta (yttrium-90-edotreotide) absorption in body tissues and to aid in determining appropriate patient dose. Onalta is in development as a targeted radiotherapeutic for the treatment of carcinoid and pancreatic neuroendocrine tumors. The in vitro and in vivo studies are part of Molecular Insight's clinical program to support a planned U.S. dosimetry trial later this year. Results were presented at the Society of Nuclear Medicine (SNM) 55th Annual Meeting in New Orleans, LA.

Onalta is a radiolabeled analog of the naturally occurring peptide, somatostatin. Somatostatin receptors are overexpressed in carcinoid and certain other neuroendocrine tumors. Onalta binds specifically to somatostatin receptors and serves as a carrier for targeted delivery of the therapeutic radioisotope, yttrium-90, to the tumor.

"These studies compared the tissue distribution and pharmacokinetic profiles of induim-111- and yttruim-90- labeled edotreotide in order to determine whether indium-111-edotreotide is a suitable imaging predictor for the organ distribution of yttrium-90-edotreotide, the radiotherapeutic peptide," said John W. Babich, Ph.D., President and Chief Scientific Officer of Molecular Insight. "Yttrium-90 delivers therapeutic radiation for tumor kill, but it does not emit gamma rays that would enable imaging with standard gamma cameras. Therefore, a surrogate imaging isotope such as indium-111 is necessary to help inform appropriate patient dosing. We believe that these studies support the suitability of indium-111-edotreotide as an appropriate surrogate imaging marker for Onalta."

"Onalta is a cornerstone of Molecular Insight's oncology portfolio of targeted radiotherapeutics for the treatment of neuroendocrine tumors," said David S. Barlow, Chairman and Chief Executive Officer of Molecular Insight. "Onalta and Azedra(TM) are complementary radiotherapeutic candidates that may have the potential to offer patients and physicians a range of options to treat neuroendocrine tumors such as carcinoid, pheochromocytoma and neuroblastoma. We in-licensed Onalta last year from Novartis Pharma AG where it underwent three Phase 1 and three Phase 2 clinical trials in more than 300 patients, and we expect to initiate a U.S. dosimetry trial in the second half of this year."

The studies evaluated the tissue distribution and pharmacokinetics of indium-111-edotreotide in two animal models. One study included in vitro studies and evaluated another potential imaging surrogate, indium-111-pentetreotide (Octreotide). Tissue distribution comparisons of the compounds in all organs were virtually identical except in the kidneys, where indium-111-edotreotide predictably and consistently overestimated the Onalta absorbed radiation dose.

One presentation is a poster study, entitled "Determination of the Ability of (111)In Onalta (Edotreotide) to be Used as an Imaging Surrogate for the Accurate Prediction of (90)Y Onalta Radiation Absorbed Dose." Authors are: John A. Barrett, Shawn M. Hillier, Katherine Kacena, John L. Joyal, and John W. Babich, of Molecular Insight Pharmaceuticals; Tamara L. Anderson, Daniel J. Irwin, and Jeffrey P. Norenberg, of the University of New Mexico Health Sciences Center, College of Pharmacy; and Michael G. Stabin and James B. Stubbs, of Radiation Dosimetry Systems, Palo Alto, CA. The second study is an oral presentation entitled, "Comparative Analysis of (111)In edotreotide, (90)Y edotreotide and (111)I pentetreotide In Vivo and In Vitro." Authors are: John C. Marquis, Shawn M. Hillier, Travis Besanger, James F. Kronauge, John A. Barrett, John L. Joyal, and John W. Babich, of Molecular Insight Pharmaceuticals; Tamara L. Anderson, Daniel J. Irwin and Jeffery P. Norenberg, of the University of New Mexico Health Sciences Center, College of Pharmacy.

About Molecular Insight Pharmaceuticals, Inc.

Molecular Insight Pharmaceuticals (NASDAQ: MIPI) is a 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, molecular radiotherapeutics and molecular imaging pharmaceuticals with initial applications in the areas of oncology and cardiology. Its lead molecular 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 and its website address is:

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 Azedra(TM), Onalta(TM), Zemiva(TM) 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. 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.


Molecular Insight Pharmaceuticals, Inc.
Priscilla Harlan, 617-492-5554
Vice President, Corporate Communications

Posted: June 2008