Background: Sipuleucel-T (Provenge®, Dendreon Corporation) is a recently approved treatment for asymptomatic or minimally symptomatic metastatic castrate-resistant prostate cancer. This technology assessment is a systematic review of studies of the clinical outcomes of sipuleucel-T treatment. The review is organized by three Key Questions. These questions address the following: 1) the outcomes of sipuleucel-T for patients meeting the U.S. Food and Drug Administration (FDA)-labeled indications; 2) the outcomes of sipuleucel-T for patients not meeting the FDA-labeled indication (“off-label use”); and 3) adverse effects of sipuleucel-T treatment. Key Questions 1 and 2 also include subquestions to address possible interactions and mediators of the outcomes of sipuleucel-T treatment.

Methods: This assessment is based on an electronic search of the literature as follows:

1. MEDLINE® (inception [1948] through July 13, 2010)

2. EMBASE® (inception [1974] through July 13, 2010)

3. Cochrane Controlled Trials Register (no date restriction)

In addition, publicly available documents available from the FDA website and some other sources such as clinicaltrials.gov and conference abstract websites were examined for relevant studies. Studies were selected to address the three Key Questions identified for this technology assessment. We abstracted data from full-length randomized, controlled trials (RCTs) and case series studies that utilized sipuleucel-T treatment for patients with prostate cancer and reported at least one clinically relevant outcome of interest.

The quality of included comparative studies was assessed using the general approach to grading evidence developed by the U.S. Preventive Services Task Force (USPSTF). The strength of the overall body of evidence was assessed using a framework developed by AHRQ for the EPC Methods Guide, based on a system developed by the GRADE Working Group.

Results: The electronic literature search yielded 47 records. Among those, 33 were excluded at initial title and abstract review and 14 were retrieved for full-text examination. Including documents retrieved from other sources, data were available from 10 nonoverlapping data sets. Data from three studies describing results of comparative studies were abstracted for studies examining the FDA-labeled indication. Data from seven studies describing results of any study design were abstracted for studies examining off-label indications. Data from a single analysis of pooled data from four comparative studies were abstracted for the analysis of adverse effects of sipuleucel-T.