A phase 3 clinical trial co-led by Mount Sinai researchers is the first to show that immunotherapy after surgery to remove bladder cancer can reduce the risk of relapse for patients who are at high risk of their cancer returning in a deadly metastatic form, according to results published in The New England Journal of Medicine. The immunotherapy nivolumab was used as an adjuvant therapy, which is given after surgery in the hopes of maximizing its effectiveness.