The German Institute for Quality and Efficiency in Health Care (IQWiG), an independent scientific institute that examines the risks and benefits of medical interventions in patients, recently reported in a press release that sipuleucel-T (trade name Provenge), a cell-based cancer immunotherapy for prostate cancer has added benefit for prostate cancer patients’ clinical outcome.
Sipuleucel-T is an autologous cellular immunotherapy where the patient’s own immune system is programmed to recognize metastatic cancer cells and attack them. The patient’s immune cells are extracted from the individual, treated in the laboratory with a specific protein, and injected back into the patient’s bloodstream where they can better identify prostate cancer cells and stimulate the immune system to fight them.
Sipuleucel-T was approved by the U.S. Food and Drug Administration (FDA) in September 2014 as a therapy for metastatic prostate cancer in men with few or no symptoms in a phase where they do not require chemotherapy. In January 2015, IQWiG indicated that sipuleucel-T had no added benefit for patients. This conclusion was based on a study conducted by Dendreon Corporation (the sipuleucel-T manufacturer) comparing sipuleucel-T to control therapies, in which IQWiG found the results incomplete and not interpretable in terms of survival rate, especially since patients received chemotherapy with docetaxel at different time-points (depending on disease progression) with docetaxel by itself exerting a positive effect on survival rates. The manufacturer then provided further data and sensitivity analysis supporting a lower mortality in patients under sipuleucel-T treatment.
Through an addendum, the IQWiG now declared that based on this new information, there is evidence of added benefits for sipuleucel-T treatment in terms of overall survival, although its extent is difficult to determine. Furthermore, the institute concluded that sipuleucel-T has shown evidence of an added benefit as a therapy in metastatic prostate cancer patients, although the extent of this benefit is currently non-quantifiable.