For the first time in more than 20 years, today the FDA granted approval to a new treatment for urothelial carcinoma, the most common form of bladder cancer.
Tecentriq, also known as atezolizumab, is an immune checkpoint blockade or inhibitor that selectively binds to cancer cells based on the presence of PD-L1, a protein on the tumor surface. This is the first PD-L1 inhibitor that has been approved by the FDA for any disease.
PD-L1 is more strongly expressed on certain types of tumors, including urothelial cancers arising from the bladder, renal pelvis, and ureters. PD-L1 prevents the body’s immune system from being able to recognize the cancer and attack it, but PD-L1 inhibitors help the body to “see” the cancer and use the immune system to fight it.
This treatment has shown promise for platinum-resistant metastatic urothelial carcinoma – an advanced cancer that does not respond to traditional chemotherapies and which so far has very few other effective therapies.
In the study that ultimately led to atezolizumab’s approval by the FDA, it was shown to be effective at helping unleash the power of the immune system to recognize and attack these tumor cells.
The patients who responded positively to this treatment can do well on it for a long time. This is sometimes referred to as having a “durable response.” Few side effects were seen with this drug and they were mild. Severe side effects were rare and tied to too much immune activity. These study results first led to the FDA granting atezolizumab priority review designation in March 2016 to put it on the fast track for full FDA approval.
Additionally, in this study the investigators identified a correlation between mutational load and response to the drug. This means that when there was a higher concentration of proteins that could be recognized by the body, there was more sensitivity to this immunotherapy.
At Weill Cornell Medicine, we have been involved in the development of several types of immunotherapy and are at the forefront of developing ways to better determine which patients are most likely to respond to treatment. We are conducting research on how mutations and the “mutational load” can lead to the formation of neoantigens and the impact these neoantigens have on immunotherapy response in order to identify the patients most likely to benefit from this therapy.
We’re very excited to be able to offer Tecentriq/atezolizumab to our patients and encourage you to inquire about whether it’s a good fit for you. Additionally, we continue our research with immunotherapy and monoclonal antibodies for patients with urothelial cancer. One open clinical trial is testing whether a single checkpoint inhibitor (targeted at PD-L1) or dual checkpoint inhibitor (targeted at both PD-L1 and CTLA4 – a protein on the T-cell) is more effective against tumors compared with chemotherapy.