Novel imaging agent utilizes protein found in scorpion venom

Researchers have combined a new imaging technique and imaging agent which utilizes a synthesized amino acid found in scorpion venom to help illuminate brain tumors during surgery.

The new imaging technique uses a custom high-sensitivity near-infrared camera coupled with a novel imaging agent tozuleristide (BLZ-100) which contains a synthetic version of an amino acid compound found in scorpion venom. The compound naturally binds to tumor cells and is attached to a fluorescent dye that glows with the help of a near-infrared laser.

"With this fluorescence, you see the tumor so much clearer because it lights up like a Christmas tree," said senior author Adam Mamelak, MD, with Cedars-Sinai Medical Center in Los Angeles, in a prepared statement.

In the phase 1 safety clinical trial, published May 9 in Neurosurgery, Mamelak and colleagues gave 17 adults with brain tumors varying doses of BLZ-100 prior to surgery. High- and low-grade tumors illuminated, but those considered high-grade showed greater “fluorescence intensity.” Patients were monitored for 30 days; the researchers did not note any serious adverse responses. They determined the imaging system was also safe for imaging brain tumors during surgery.

The researchers wrote that more clinical trials are needed to test the imaging system’s safety and the effectiveness of BLZ-100, but they believe their technique could prove useful for many different types of cancer.

Phase II is currently underway and involves testing the imaging camera and agent in pediatric brain tumors across 14 sites in the U.S.

"The technique in this study holds great promise not only for brain tumors but for many other cancer types in which we need to identify the margins of cancers," said co-author Keith L. Black, MD, chair of the department of neurosurgery at Cedars-Sinai, in the same statement. "The ultimate goal is to bring greater precision to the surgical care we provide to our patients."

Some of the authors disclosed that they are consultants for Blaze Bioscience, creators of BLZ-100, including Mamelak. Black and Mamelak are also shareholders of Blaze.