A surgeon has helped develop the first-ever molecule that illuminates nerve tissue, helping make surgery both faster and safer.
The first-of-its-kind drug binds to nerve tissue and fluoresces, enabling surgeons to better see the nerves as they operate.
A study in Nature Communications reported that bevonescein – a short chain of amino acids attached to a fluorescing molecule – safely highlights longer stretches of nerves than would be visible to the naked eye, improving the odds of operating without causing injury.
Ryan Orosco, an associate professor and otolaryngologist (head and neck surgeon) in the UNM School of Medicine, co-authored the paper. He said: ‘The way that I explain this drug to patients is that I think if we can help surgeons see things better, they can do faster, more efficient, safer surgery.’
The journal article reported on a small Phase 1-2 study of the drug, which was tested on 27 cancer patients to evaluate its safety and efficacy.
Orosco added: ‘The trial was for patients having a neck dissection to remove lymph nodes, or a parotid surgery or a thyroid surgery. In all of those cases, there are cranial nerves that are important to identify, work around and protect.’
A larger Phase 3 study is currently underway, which includes patients at UNM Hospital, and is expected to be completed by this summer.
It will assess whether the use of the imaging agent meaningfully improves overall surgical outcomes, a question the initial trial was not designed to address.
Orosco’s involvement in the development of the drug dates back to his ENT residency at the University of California, San Diego, where he spent a year-long research fellowship in the lab of Quyen Nguyen.
She had worked closely with the late biochemist Roger Tsien, PhD, who won the Nobel Prize in 2008 for discovering green fluorescent protein, enabling the development of methods to ‘tag’ specific molecules and tissue types, such as cancer cells.
Nguyen’s research eventually led to the development of bevonescein, and Orosco, who went on to do a head and neck cancer fellowship at Stanford before joining the UCSD faculty, played a role in developing the clinical trial protocol and performed many of the surgeries in the study.
He joined the UNM faculty in late 2022 and now serves as the national principal investigator for the Phase 3 trial of the drug, which now includes 10 sites.
Patients in the trials receive an IV infusion of the drug prior to surgery, but the kidneys quickly clear it.
Orosco said: ‘We can image them five, six, seven, eight hours later, and it still stays bound to the nerves, but it flushes out of the body within 12 hours.’
An upcoming phase of the research will evaluate the use of specially modified headband-mounted magnifying loupes.
Testing those loupes in a spin-off trial is, Orosco explained, a critical and practical step toward real-world implementation.
If the Phase 3 trial shows clear clinical benefit from the use of bevonescein during head and neck surgery, it could win FDA approval, leading to wider adoption.
