Sipuleucel-T Survival Benefit Greater in Blacks
Median overall survival was 9.3 months longer for black versus white patients with metastatic castration-resistant prostate cancer.
|The following article is part of conference coverage from the 2017 American Urological Association meeting in Boston. Renal and Urology News' staff will be reporting live on medical studies conducted by urologists and other specialists who are tops in their field in kidney stones, prostate cancer, kidney cancer, bladder cancer, enlarged prostate, and more. Check back for the latest news from AUA 2017.|
BOSTON—Treatment with sipuleucel-T is associated with longer overall survival in blacks versus whites with metastatic castration-resistant prostate cancer (mCRPC), according to data presented at the American Urological Association 2017 annual meeting.
In a study led by A. Oliver Sartor, MD, the Laborde Professor of Cancer Research at Tulane University School of Medicine in New Orleans, black patients had an additional median overall survival (OS) benefit of 9.3 months compared with white patients (37.3 vs 28.0 months). In addition, among patients who had PSA levels below the median (26.8 ng/mL) at the time of treatment, black men had an OS benefit of almost 2 additional years compared with whites (54.3 vs 33.4 months).
On multivariate analysis, black race was an independent baseline predictor of improved OS following treatment with sipuleucel-T, the investigators reported.
The findings reported by Dr Sartor's team are based on 630 men with mCRPC enrolled in the PROCEED registry. The cohort consisted of 210 blacks and 420 whites matched by baseline PSA level.
Sipuleucel-T, which is marketed as Provenge by Dendreon Pharmaceuticals, is an autologous cellular immunotherapy approved by the FDA in April 2010 for the treatment of asymptomatic or minimally symptomatic mCRPC.
Evidence shows that the incidence of prostate cancer and the mortality rate from the disease is substantially higher among black than white men.
In an interview with Renal & Urology News, Dr Sartor said he was surprised by the racial difference in survival. “We've kind of gotten accustomed to African Americans doing worse, and this was a reversal of that theme. I'm thinking that the most likely explanation is African-American immune systems are a little bit different. In this case, they're different in a favorable way.”
Dr Sartor postulated that blacks either have a more robust immune system or their tumors are more responsive to immunotherapy compared with whites.
Africa, he noted, is rife with infectious diseases and “it very well could be that the American-American immune system is geared to be more active.”
Dr Sartor said he always thought that the place of sipuleucel-T is in relatively early-stage asymptomatic disease, but “now I'm really thinking about it for the African-American population.”
Sartor AO, Armstrong A, Ahaghotu C, et al. Overall survival analysis of African American and Caucasian patients receiving sipuleucel-T: Preliminary data from the PROCEED registry. [abstract] J Urol 2017;197(4S):e456-e457. Oral presentation at the American Urological Association 2017 annual meeting in Boston on May 13, 2017. PD24-12.