GU Cancers Symposium 2013 - Immune response to sipuleucel-T in patients with metastatic castrate-resistant prostate cancer (mCRPC): Phase 2 ProACT study, by Thomas A. Gardner, MD, et al. - Session Highlights

ORLANDO, FL, USA ( - This study is part of the ongoing ProACT study. The investigators evaluated immune response and overall survival of sipuleucel-T (based on three different concentrations of PA2024). In this poster, they report on the FDA-approved concentration of 10 µg/mL.

gucancerssympalt thumb thumbOf the 40 men with asymptomatic or minimally symptomatic metastatic castrate-resistant prostate cancer receiving this concentration in three infusions (Table 1 from ASCO GU poster), the data indicates that sipuleucel-T, both the memory B cells and the mature phenotype cells were activated (memory B cells are defined as CD20+ IgD- CD27+ CD86+ and mature phenotype cells are defined as CD20+ IgD+ CD27+ CD86+). This data confirms results reported in the neoadjuvant setting (Sheikh NA et al. J Clin Onco 2012, Suppl 5, Ab 178).

Overall, sipuleucel-T has the capacity to generate long-lasting anti-PA2024 and anti-PAP responses and evolves into an IgG phenotype. Sipuleucel-T (Provenge®) is an autologous cellular immunotherapy approved by the U.S. FDA for the treatment of asymptomatic or minimally symptomatic mCRPC.


Presented by Thomas A. Gardner,1 Daniel Peter Petrylak,2 John M. Corman,3 Simon Hall,4 Ralph Weinstein,5 Robert Keyser,6 Robert Brownell Sims,6 Amanda Sanders,6 Nadeem A. Sheikh,6 and Celestia S. Higano7 at the 2013 Genitourinary Cancers Symposium - February 14 - 16, 2013 - Rosen Shingle Creek - Orlando, Florida USA

1Urology Indiana University Health, Indianapolis, IN, USA; 2Columbia University Medical Center, New York, NY, USA; 3Virginia Mason Medical Center, Seattle, WA, USA; 4Mount Sinai School of Medicine, New York, NY, USA; 5US Oncology, Portland, OR, USA; 6Dendreon Corporation, Seattle, WA, USA; 7School of Medicine, University of Washington, Seattle, WA, USA

Written by Karen Roberts, medical editor for

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