POLAR trial
Research type
Research Study
Full title
A Phase I study of tumour cryOabLAtIon in combination with ipilimumab and nivolumab in front-line treatment of metastatic Renal cell carcinoma
IRAS ID
1010229
Contact name
Naveen Vasudev
Contact email
Sponsor organisation
University of Leeds / LTHT Joint Sponsor QA Office (CTIMPs), Directorate of Governance and Compliance
Research summary
The current management of kidney cancer that has spread beyond the kidney to surrounding organs includes giving immunotherapy which is medication designed to boost the immune system by training the body to better recognise and attack cancer cells.
Unfortunately a quarter of kidney cancers do not respond to this treatment (called resistance) and half of patients will develop further cancer spread after a year of treatment. These medications can also give patient’s side effects such as diarrhoea, skin rashes and trouble breathing.
Better ways to treat advanced kidney cancer are required and ways to overcome drug resistance in order to prolong the effect of available medications.
One way to do this is to find ways to prepare the immune system better for immunotherapy, by offering other treatments first. Cryoablation involves freezing cancer cells by inserting small needles into the cancer using x-ray guidance. This has been shown to kill cancer cells but also help the body to familiarise itself with the cancer and provide a spark for the immune system. Based on previous research, it has been shown that if immunotherapy is given after cryoablation then it can be more effective and acts as reinforcements to rally the immune system’s troops for attacking the cancer cells. In other words, it is hypothesised that the combination of cryoablation and immunotherapy is complimentary in amplifying the body's natural ability to fight cancer.
In this trial, we will investigate the safety of delivering both treatments together in patients with advanced kidney cancer. Patients will be closely monitored to see how they respond and if they develop any side effects. The trial will also help improve our understanding of how this combination therapy impacts the body's immune and inflammatory response to allow for fine-tuning of future therapies for even greater effectiveness.REC name
Yorkshire & The Humber - Leeds East Research Ethics Committee
REC reference
25/YH/0204
Date of REC Opinion
12 Nov 2025
REC opinion
Further Information Favourable Opinion