Celecoxib Versus Placebo for Men With Prostate Cancer and a Rising Serum Prostate-Specific Antigen After Radical Prostatectomy and/or Radiation Therapy

Abstract

To assess the biologic activity of celecoxib, a selective cyclooxygenase-2 inhibitor, in men with recurrent prostate cancer using change in prostate-specific antigen (PSA) doubling time (PSADT) as the primary outcome variable. Participants had histologically confirmed prostate cancer, no recent hormone therapy, rising serum PSA after radical prostatectomy and/or radiation therapy, and no radiographic evidence of metastases. Patients were randomly assigned to celecoxib (400 mg by mouth twice daily) or placebo. Treatment continued until disease progression or until adverse effects stopped treatment. A positive outcome was defined as post-treatment PSADT of more than 200% baseline PSADT with no new metastases. The study was terminated early after information about the cardiovascular safety of celecoxib prompted review of ongoing clinical studies. Before discontinuation of the study, 78 men were assigned randomly to either celecoxib or placebo. Eight (20%) of 40 men in the placebo group and 15 (40%) of 38 men in the celecoxib group had post-treatment PSADT of more than 200% of baseline PSADT with no new metastases (P = .08). Mean PSA velocity increased by 3.0% for the placebo group and decreased by 3.4% for the celecoxib group (P = .02). Although the primary efficacy objective was not met, this study provides some evidence for biologic activity of celecoxib in prostate cancer. Compared with placebo, celecoxib significantly decreased mean PSA velocity and tended to increase the proportion of men who doubled their PSADT.