A new drug for advanced bladder cancer received approval from the Food and Drug Administration (FDA) on May 18. Atezolizumab is an immunotherapy treatment designed to boost the body’s defenses against cancer.

Sold under the brand name Tecentriq, the drug treats advanced urothelial carcinoma in patients whose conditions have gone worse while undergoing or after chemotherapy. It is the first in the class of medications called PD-1/PD-L1 inhibitors, which target the pathway cancer uses to evade detection.

“[W]hat cancer cells do is they preferentially co-opt off-switches to evade the immune system and basically run rampant and spread throughout the body," said Dr. Arjun Balar, an oncologist from NYU Langone Medical Center to CBS News, adding that the drug works to recover the body’s control of such off-switches to fight cancer.

Urothelial carcinoma is the most prevalent type of bladder cancer, with more than 76,000 estimated new cases and 16,000 deaths from the disease this year.

Tecentriq was tested in a clinical trial involving 310 patients, where 14.8 percent saw partial tumor shrinkage from two to 13 months. There was a greater effect among patients categorized as positive for PD-L1 expression, suggesting that the level of this expression in immune cells may better identify patients who are more likely to respond and benefit from the medication.

This drug manufactured by Genentech is well-tolerated, but could come with side effects such as fatigue, reduced appetite, urinary tract infection, fever, nausea and constipation, as well as the risk of “immune-mediated” reactions that could affect healthy organs like the lungs and colon.

The FDA approved the drug under the “breakthrough therapy designation” system, helping to expedite drug development and review.

The regulatory agency also approved on May 17 a similar drug from Bristol-Myers Squibb Co., one used for treating Hodgkin lymphoma, the fourth type of cancer for which it has been approved in the country.

Both drugs belong to a new breed of injected cancer therapies that work with the patient’s immune system, prompting it to hunt and kill tumor cells that would otherwise multiply via mechanisms of hiding from immunity.

Drugmakers are in a race to create such immunotherapy drugs, with some already significantly improving patient survival in decades.

Photo: Ed Uthman | Flickr