Updated Results From SPARTAN Trial on Apalutamide in Prostate Cancer
Posted: Wednesday, November 6, 2019
Updated data from the phase III SPARTAN study, presented at the European Society for Medical Oncology (ESMO) Congress 2019 in Barcelona (Abstract 843O) and published in the Annals of Oncology, supported the use of concurrent apalutamide and androgen-deprivation therapy as a standard option for men with high-risk nonmetastatic castration-resistant prostate cancer. Matthew R. Smith, MD, PhD, of Harvard Medical School, Boston, and colleagues found that apalutamide was associated with a 25% reduction in deaths compared with placebo.
The investigators randomly assigned 1,207 patients with nonmetastatic castration-resistant prostate cancer 2:1 to receive apalutamide or placebo, with ongoing androgen-deprivation therapy. This trial reported a second interim analysis, after 285 overall survival events.
After a median follow-up of 41 months, apalutamide was associated with improved survival versus placebo (P = .0197); however, the results did not meet the prespecified significance cutoff of P = .0121. The 4-year overall survival rates for patients receiving apalutamide or placebo were 72.1% and 64.7%, respectively. In the analysis, 68% of patients in the placebo group received subsequent life-prolonging therapy compared with 38% of patients in the apalutamide group.
No new safety signals with apalutamide emerged in this update. There was no significant change in the rates of treatment-emergent adverse events for apalutamide between the first and second analyses. The rates of treatment discontinuation due to progressive disease were 34% and 74% in the apalutamide and placebo groups, respectively; the treatment discontinuation rate due to adverse events was 14% in the apalutamide group and 8% in the placebo group.
“These results further support apalutamide as a standard of care option for patients with high-risk nonmetastatic castration-resistant prostate cancer,” the investigators concluded.
Disclosure: For full disclosures of the study authors, visit academic.oup.com.