First-in-human clinical trial attacks pancreatic cancer with laser light

A team in the US is investigating a first-in-human vascular-targeted photodynamic therapy designed to destroy pancreatic tumours encasing major abdominal vessels, potentially enabling subsequent surgical resection.
The UCI Health Chao Family Comprehensive Cancer Centre is conducting a phase 1 clinical trial to evaluate vascular-targeted photodynamic therapy (VTP) in patients with localised but surgically unresectable pancreatic tumours.
Led by interventional radiologist Nadine Abi-Jaoudeh, a nationally recognised specialist in image-guided cancer therapy, the trial uses the light-sensitive agent padeliporfin alongside intravascular laser illumination.
The approach aims to target tumour tissue surrounding major blood vessels while preserving the vessels themselves.
UCI Health is one of only two US cancer centres currently evaluating the technology, which was developed by Israel-based biotechnology company ImPact Biotech.
The treatment is performed after intravenous administration of padeliporfin. A catheter is advanced into the tumour-encased vessel, and a balloon-mounted laser illumination device is positioned within the treatment area.
Nadine Abi-Jaoudeh explained: ‘First, we inject the patient with a light-sensitive drug. Then we insert a balloon into the tumour-encased blood vessel. Inside the balloon is a laser. When we turn it on, that activates the drug, killing the tumour surrounding the vessel.’
Laser illumination activates padeliporfin within the vascular compartment, triggering a photochemical reaction that damages the tumour vasculature and destroys the tumour.
The phase 1 protocol delivers illumination in two five-minute treatment cycles. Investigators are evaluating three incremental laser doses to identify an effective treatment level while assessing safety.
The rationale for the approach is particularly relevant in pancreatic cancer, where vascular involvement can preclude curative-intent surgery.
About half of patients present with localised disease, but many are not candidates for resection because the tumour involves or encases major abdominal arteries. In these cases, surgical dissection may carry substantial vascular risk.
Preliminary results published in the Journal of Vascular and Interventional Radiology described the first three patients treated with padeliporfin-based VTP. Three additional patients have since undergone treatment.
Among the six patients treated to date, four subsequently underwent surgical removal of residual tumour tissue. Of those four, three had no evidence of tumour at the surgical margins.
The investigators view the findings as an early indication that local photodynamic treatment could facilitate resection in a subset of patients whose disease would otherwise be considered unresectable.