Contributing Writer

In a move to expand its pipeline of radiopharmaceuticals for molecular imaging and treatment, Molecular Insight Pharmaceuticals Inc. acquired Solazed (ZK-BA) from Berlin-based Bayer Schering Pharma AG.

Specific terms of the deal were not disclosed, but Molecular Insight will pay Bayer Schering a licensing fee, regulatory milestones and royalties on future sales. In exchange, the Cambridge, Mass.-based company gets exclusive, worldwide rights to Solazed, a small-molecule benzamide compound that targets melanin, which is over-expressed in an estimated 40 percent of melanoma tumors.

Early stage data indicate Solazed can be labeled with Iodine-131 for use in targeting radiation therapy to the tumor or with Iodine-123 for imaging of the tumor. In an investigator-sponsored trial in Europe, the compound displayed significant and prolonged accumulation in melanoma tumors, and preclinical studies have shown Solazed can reduce tumor volume and increase survival in murine xenograft models.

The acquisition of Solazed represents Molecular Insight's first foray into the notoriously challenging field of melanoma.

According to the American Cancer Society, more than 62,000 new cases were diagnosed last year. If caught and treated early, the five-year survival rate for melanoma tops 98 percent, but that figure drops drastically to 16 percent for patients diagnosed with late-stage disease. Improving advanced melanoma treatment options - which currently include chemotherapy and immunotherapy - has long been a goal for biotechnology companies, but the disease has proven stubborn.

Late last year, Onyx Pharmaceuticals Inc. took a hit after kinase inhibitor Nexavar (sorafenib), which is approved for kidney cancer, failed to improve progression-free survival in a Phase III melanoma trial.

Other high-profile melanoma setbacks have included CancerVax Corp.'s Phase III failure with melanoma vaccine Canvaxin and Genta Inc.'s Phase III failure with antisense drug Genasense, which prompted the FDA's Oncologic Drugs Advisory Committee to vote against approval in that indication. (See BioWorld Today, May 4, 2004, Oct. 5, 2005, and Dec. 5, 2006.)

Yet setbacks such as those don't seem to be a deterrent for Molecular Insight or others: Research and Markets reports more than 100 melanoma drugs in development. And not all the news has been bad: SciClone Pharmaceuticals Inc.'s immunomodulator Zadaxin demonstrated encouraging interim Phase II results in melanoma late last year, and Genasense may scrape a European approval for melanoma when the regulatory decision comes down this quarter. (See BioWorld Today, Dec. 18, 2006, and Dec. 26, 2006.)

While Solazed is Molecular Insight's first melanoma drug, it joins several other radiopharmaceuticals for cancer in the company's pipeline. Last year, Molecular Insight initiated a Phase I trial with Azedra, a radiotherapeutic designed to maximize the delivery of radiolabeled MIBG molecules to neuroendocrine tumors such as carcinoid, pheochromocytoma and neuroblastoma. A preclinical oncology compound, MIP-220, also is in development for detection and monitoring of prostate cancer.

The crown jewel of Molecular Insight's pipeline, however, is not in oncology, but cardiology. The company is conducting a Phase II program with Zemiva (iodofiltic acid I 123) for the diagnosis of cardiac ischemia in chest pain patients. Funding for the trials comes from more than $50 million in venture capital funding raised to date, as well as $4 million in grants from the National Institutes of Health. Molecular Insight filed to go public in late 2005, but as of now remains private. (See BioWorld Today, Nov. 10, 2005).