Adding immunotherapy to standard anti-rejection medication may help kidney transplant recipients with cancer, with research showing it can reduce the risk of organ rejection and eliminate cancer in a quarter of patients.

Researchers at Royal Adelaide Hospital and the University of South Australia found a combination of transplant anti-rejection drugs and immune checkpoint inhibitors reduced organ rejection rates from as high as 50 per cent down to 12 per cent, and also eradicated cancer cells in 25 per cent of patients.

Immune checkpoint inhibitors are drugs that block proteins, that help keep immune responses from being too strong, important for organ recipients.

Those proteins can also keep T-cells from killing cancer cells but when blocked the T-cells can work more effectively. 

UniSA researcher and Royal Adelaide Hospital renal specialist Rob Carroll said the study’s findings were a game-changer for kidney transplant patients with incurable cancer.

“Cancer is a leading cause of death in kidney transplant recipients with the rate of cancer being three-times higher in this group, than in the general population,” Associate Professor Carroll said.

“The terrible irony is that the immunosuppressants that patients must always take to stop their immune systems attacking their transplants, are also the medicines that stops the immune system getting rid of pre-cancer cells.

“To correct this imbalance, our study tested the efficacy of maintaining baseline anti-rejection drugs, to protect the transplant and adding immune checkpoint inhibitors, to attack the cancer.”

Published in Lancet Oncology, the world-first study assessed 22 patients with a renal transplant and incurable locally advanced or metastatic cancer that had progressed despite first-line standard anti-tumour treatment. 

They kept their standard anti-rejection drugs unchanged and were treated with an immune checkpoint inhibitor, nivolumab.

Associate Prof Carroll said patients responded well with lower rates of organ rejection while cancer cells were eliminated in a quarter.

“It’s a massive advancement for kidney transplant patients; a whole new lease on life,” he said.