March 11, 2021
Adding immunotherapy may improve upon chemo alone
- Single-arm studies have shown that immune checkpoint inhibitors plus chemotherapy produce complete response rates of 30 to 45%
- Researchers are investigating the use of an oncolytic virus to improve upon those rates
- Other combination treatments are also being studied
The standard treatment for locally invasive bladder cancer is neoadjuvant chemotherapy followed by radical cystectomy. Recently, a number of studies have found that immune checkpoint inhibitors such as pembrolizumab (brand name: Opdivo), atezolizumab (brand name: Tecentriq), and durvalumab (brand name: Imfinzi) in the neoadjuvant setting are equivalent, and sometimes better than chemotherapy alone.
“That’s generated a lot of excitement,” Dr. Roger Li, urologic oncologist at the Moffitt Cancer Center in Tampa, FL, tells SurvivorNet Connect. He cautions that these were single-arm studies that still need to be validated — a lesson learned from AstraZeneca pulling Imfinzi from the metastatic bladder cancer indication. “It is encouraging, though, that these single-arm studies consistently produce 30 to 45% complete response rates in the cystectomy specimens that are removed after neoadjuvant immune checkpoint blockade.”
He is the principal investigator of a study at Moffitt that is seeking to improve upon those results. Dr. Li and his team are infusing an oncolytic virus into the bladder that is known to be effective in the BCG refractory setting, in the hope that the oncolytic virus will generate a more robust immune response. “That can act as the match to light the fire, so to speak, and can be used in conjunction with immune checkpoint blockades to more effectively control the cancer,” he says.
Similar strategies are also under investigation. “Combination treatments using different agents that act as sort of a local inciter of the immune response so that the immune checkpoint blockade, when added on as a combination therapy, can be even more efficacious.”