An experimental therapy for bladder cancer in on the brink of entering Phase I clinical trials in the UK after a development pact was signed between Cancer Research UK, its commercial arm Cancer Research Technology, and Canadian biotech Sitka Biopharma.

Sitka’s STK-01 is being developed to improve the delivery of chemotherapy in non-muscle invasive bladder cancer (NMIBC) in patients whose tumour has not yet penetrated into the muscle layer of the bladder wall, using a unique nanoparticle polymer technology to deliver the drug docetaxel.

While docetaxel is an effective chemotherapy, it can be difficult to deliver enough of the drug to the bladder to treat the cancer. It is hoped that STK-01 may overcome this by enhancing penetration and retention of the drug in the bladder wall. According to the charity, in preclinical trials the therapy was shown to be “extremely effective” at eliminating tumours in mouse models.

CR UK and Sitka will share the cost of the development and production of STK-01 for the clinic; the charity’s Centre for Drug Development will then fund and manage a Phase I clinical trial of the drug in bladder cancer patients to evaluate its safety, toxicity, drug delivery and how it compares with giving docetaxel alone.

The trial will take place across the Experimental Cancer Medicine Centres (ECMC) network, a nationwide initiative funded by Cancer Research UK and the UK’s four Health Departments.

“More than 5,000 people die from bladder cancer each year in the UK and we urgently need to find new and better ways to treat patients. We hope this experimental approach will improve survival for patients with invasive disease by increasing the amount of chemotherapy that can reach the tumour,” said Dr Nigel Blackburn, Cancer Research UK’s director of drug development.