Washington Editor

Guilford Pharmaceuticals Inc. regained all rights to develop and commercialize its NAALADase inhibitors, but in the process lost a potential $10 million milestone payment.

A day before the milestone was due, New York-based Pfizer Inc. terminated its exclusive worldwide license to develop Guilford's N-acetylated-alpha-linked-acidic-dipeptidase inhibitors in all diseases for which it held rights, including the main area of neurodegenerative disorders.

As per the $15 million deal signed by the parties last May, Pfizer reserved the right to terminate the deal by the end of March if it was unable to identify a lead clinical candidate that met its internal criteria for development, Stacey Jurchison, Guilford's director of corporate communications, told BioWorld Today.

On signing the deal, Pfizer paid Guilford a $5 million fee. (See BioWorld Today, May 9, 2003.)

Craig Smith, president and CEO of Baltimore-based Guilford, released a prepared statement describing the Pfizer deal as "a good scientific and business relationship." However, he said, the two were unable to reach an agreement on a potential extension of the license.

Thus, Guilford regains its rights and is poised to seek other corporate partnerships for this early stage program. Indeed, the Pfizer deal was not a complete loss as the firm was successful in validating the target and demonstrating efficacy of NAALADase inhibitors in preclinical models of neuropathic pain, Jurchison said.

NAALADase, a membrane-bound enzyme found primarily in the central and peripheral nervous systems, is believed to play a role in modulating the release of glutamate, which may increase during acute injury or chronic neurodegenerative disorders and lead to cell injury and death.

In animal models of diabetic peripheral neuropathy and neuropathic pain, Guilford said NAALADase inhibitors normalized pain sensitivity, increased nerve conduction velocity and prevented or slowed peripheral nerve degeneration.

Guilford has 37 U.S. patents and 10 pending patent applications protecting its NAALADase inhibitor technology. While Pfizer held rights to most potential applications for 10 months, Guilford had retained rights to prostate cancer, drug addiction and head and spinal cord trauma.

As such, the company has initiated other collaborations, including a prostate cancer relationship with Memorial Sloan-Kettering Cancer Center in New York. NAALADase is the same protein as prostate-specific membrane antigen, a protein found on the surface of prostate cancer cells, Guilford said.

In another agreement, the National Institute for Drug Addiction of the National Institutes of Health in Bethesda, Md., is studying NAALADase inhibitors as a potential treatment for cocaine addiction.

Guilford markets the Gliadel Wafer for the treatment of brain cancer and Aggrastat Injection for acute coronary syndrome. The firm's pipeline includes a novel anesthetic, Aquavan Injection, and potential treatments for Parkinson's disease and peripheral nerve injury.

The news was released Tuesday afternoon. The company's stock (NASDAQ:GLFD) gained 6 cents Tuesday and fell 17 cents Wednesday, closing at $7.28.