New ultrasound treatment ‘improves cancer drugs’

A new ultrasound treatment promises to improve the effectiveness of chemotherapy and treat chronic lower back pain.

Researchers from Oxford University have developed a way to use a combination of nanoparticles and ultrasound signals to effectively pump drug molecules deeper into a tumour than they would naturally travel.

The technique, which also allows doctors to monitor the progress of the drugs in real time, could enable chemotherapy drugs to kill more cancer cells and create a greater chance of destroying the tumour altogether.

‘This is a slightly different philosophy to improving outcome of cancer therapy, because there is a tendency to say we need better drugs,’ said lead researcher Prof Constantin Coussios, co-founder of spinout firm OxSonics, which is looking to commercialise the treatment.

‘This technology will, in a very cost-effective way, give to all current drugs a much better chance of being curative rather than just lengthening survival.’

Chemotherapy drugs are typically injected into the blood stream and kill the cancer cells they encounter as they are absorbed by the body.

But cancer cells can grow at much greater distances from blood vessels than normal cells and there is typically much more pressure inside a tumour than the rest of the body, often making it impossible for drug molecules to reach all the target cells.

The ultrasound technique works by creating tiny bubbles around novel nanoparticles that are injected along with the drugs. When the bubbles collapse, they agitate the blood stream and force the drug molecules deeper into the tumour.

The collapsing bubbles also generate their own sound signal across a range of frequencies that can be detected using multiple receivers and used to create a real-time three-dimensional map of where in the body the drug has travelled to.

Coussios’s team has so far trialled the technique on human tumours implanted into mice, which were found to be twice as likely to survive when they received the treatment.

OxSonics has raised £2.7m to scale up the technology to make it suitable for clinical trials with human patients, starting with cases of metastatic liver cancer.

‘In the short term we could see significant improvements in patient outcomes and I hope with right next-generation drugs and immune therapies we might even be able to make them curative,’ said Coussios.

Ultrasound is already used as an alternative to surgery to remove isolated early-stage cancers, effectively cooking them with a beam of sound waves. But until now it hasn’t been used to treat more diffuse tumours, which make up around 90 per cent of cases of metastatic liver cancer.

The researchers also plan to adapt the technique to treat chronic lower back pain, using the ultrasound bubbles to fracture and remove the centre of intervertebral discs, which cause pain if they degenerate. These centres could then be replaced with injected hydrogels, providing an alternative to existing spinal fusion surgery.