Apalutamide Improves Outcomes by Reducing Prostate Specific Antigen Progression in Non-Metastatic Castration-Resistant Prostate Cancer

Two studies assessed prostate specific antigen (PSA) progression in patients treated with apalutamide (Erleada, Janssen) and the association between PSA doubling time and survival.

Data from 2 studies demonstrated a positive clinical benefit for patients with non-metastatic castration-resistant prostate cancer (nmCRPC) treated with apalutamide (Erleada, Janssen), according to a press release.

According to a post-hoc analysis from the phase 3 SPARTAN study, apalutamide significantly reduced the risk of prostate specific antigen (PSA) progression in patients with nmCRPC who had rapidly rising PSA while receiving continuous androgen deprivation therapy (ADT).

In the trial, apalutamide decreased the risk of PSA progression by 94% compared with the placebo group. Additionally, the median time to PSA response was 29 days in the group treated with apalutamide plus ADT. At 12 weeks, median PSA decreased by 90% in patients who received apalutamide and increased by 40% in the placebo group.

Apalutamide plus ADT improved metastasis-free survival by 2 years compared with placebo plus ADT.

In the population-based study, apalutamide (Erleada, Janssen) increased survival time in patients with nmCRPC. Data demonstrated the association between shorter PSA doubling with shorter time to metastasis or death.

The relative 5-year survival rate for patients with distant stage prostate cancer is 30%, meaning it is imperative to delay the onset of metastasis in patients with nmCRPC, according to the press release.

According to the data, PSA doubling time of £10 months was associated with shorter metastasis-free survival (MFS) and overall survival (OS) and was a marker for high-risk disease. Of the patients with evaluable PSA doubling time, 38.2% were defined as high-risk and 61.8% as low-risk, with a median MFS of 15.2 and 30.5 months, respectively, and a median OS of 36 and 57.6 months, respectively.

“Patients with non-metastatic castration-resistant prostate cancer are at risk for metastases and mortality. In these patients, PSA doubling time is an important predictor of outcomes,” Eric Small, MD, FASCP, co-principal investigator of the study, said in the press release. “This analysis further underscores the efficacy of apalutamide therapy and helps us understand how PSA changes in these patients are associated with clinical outcomes.”

Reference

Erleada Significantly Reduced Risk of Prostate Specific Antigen (PSA) Progression in Patients with Non-Metastatic Castration-Resistant Prostate Cancer [news release]. Janssen’s website. http://www.janssen.com/erleadatm-significantly-reduced-risk-prostate-specific-antigen-psa-progression-patients-non. Accessed May 23, 2018.