"The immune checkpoint blockade drug nivolumab reduced tumor burden in . percent of patients with metastatic bladder cancer regardless of whether their tumors had a biomarker related to the drugs target according to clinical trial results from The University of Texas MD Anderson Cancer Center. The study will be presented Sunday June   at the  American Society of Clinical Oncology Annual Meeting. The response rate is better than weve seen for other potential secondline treatments and nivolumab is really welltolerated which is important because bladder cancer patients are a fragile group after frontline treatment with platinum chemotherapy said Padmanee Sharma M.D. Ph.D. professor of Genitourinary Medical Oncology at MD Anderson. Nivolumab unleashes an immune system attack on cancer by blocking activation of a protein called PD on T cells white blood cells that find and attack cells viruses or bacteria that have specific targets. PD acts as a brake or checkpoint to shut down activated T cells. PD is turned on by a ligand called PDL which is often found on cancer cells and other types of cells. The presence of PDL on a patients tumor has been considered a potential biomarker to guide treatment. The study found no significant difference in response rates between those with little to no PDL on their tumors  percent and those with greater PDL expression  percent. We can get good results without choosing to treat patients based on PDL status said Sharma who also is scientific director of MD Andersons immunotherapy platform and an investigator with the Parker Institute for Cancer Immunotherapy at MD Anderson. The platform is part of MD Andersons Moon Shots Program launched in  to reduce cancer deaths by accelerating development of therapies prevention efforts and early detection from scientific discoveries. This Phase III clinical trial treated  patients five . percent had complete responses   percent had partial responses in which tumor burden shrinks by at least  percent and  . percent had stable disease. Thirty  percent patients had disease progression. Treatmentrelated side effects included mainly lowgrade fatigue itching elevated lipase rash nausea joint pain and anemia. Grade  or  side effects occurred in . percent of patients. Two patients discontinued therapy because of adverse events related to the drug. At a median follow up of  days . percent remained on treatment and . percent of patients survived for at least one year which Sharma noted is better than anything weve seen in the past.  Overall survival will be analyzed in conjunction with the Phase II portion of this clinical trial which provides nivolumab or a combination of nivolumab plus the immune checkpoint inhibitor ipilimumab. The trial allows patients to cross over to the combination if nivolumab alone fails. Initial results from the Phase II portion of the trial will be presented later this year. Both nivolumab known as Opdivo and ipilimumab known as Yervoy were developed and marketed by BristolMyers Squibb which funded the clinical trial. Ipilimumab targets the CTLA checkpoint on T cells and was the first immune checkpoint inhibitor. It was based on the research of Jim Allison Ph.D. chair of Immunology executive director of the immunotherapy platform and director of the Parker Institute for Cancer Immunotherapy at MD Anderson.  Ipilimumab was the first drug ever shown to extend the survival of patients with metastatic melanoma. Longterm follow up shows  percent of those treated with the drug survive  years or longer. Nivolumab has been approved by the U.S. Food and Drug Administration for advanced melanoma lung cancer kidney cancer and Hodgkin lymphoma. The fiveyear survival rate for those with metastatic melanoma treated with nivolumab is  percent. The twoyear survival rate of patients treated with both drugs in combination is  percent. Until May  there were no drugs approved for secondline treatment of metastatic bladder cancer. The U.S. FDA approved atezolizumab which blocks PDL for these patients. Coauthors with Sharma who presented the data at ASCO are Petri Bono Helsinki University Hospital Helsinki Finland Joseph Kim Yale Cancer Center Pavlina Spiliopoulou Beatson West of Scotland Cancer Centre Glasgow Emiliano Calvo Centro Integral Oncolgico Clara Campal MadridSpain Rathi Pillai Emory Winship Cancer Institute Atlanta Patrick Ott Dana Farber Cancer Institute Boston Filippo DeBraud Istituto Nazionale dei Tumori Milan Italy Michael Morse Duke University Medical Center Durham N.C. Dung Le Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins Baltimore Dirk Jaeger Heidelberg University Hospital Heidelberg Germany Emily Chan Vanderbilt University Nashville Tenn. Chris Harbison ChenSheng Lin Marina Tschaika Alex Azrilevich of BristolMyers Squibb and Jonathan Rosenberg of Memorial Sloan Kettering Cancer Center."