Nonmetastatic Castration-Resistant Prostate Cancer: Benefits/Risks of Second-Generation AR Inhibitors in Older Men
Posted: Thursday, September 16, 2021
Harpreet Singh, MD, of the U.S. Food and Drug Administration (FDA), and colleagues conducted a study to evaluate the benefit-risk profile of second-generation androgen receptor (AR) inhibitor therapy in older men with nonmetastatic castration-resistant prostate cancer. The results of this exploratory pooled analysis, published in The Lancet Oncology, support the use of these agents in this patient population.
Using data from three clinical trials in the FDA database, the investigators identified patients with nonmetastatic castration-resistant prostate cancer who were administered an AR inhibitor (apalutamide, enzalutamide, or daralutamide; n = 2,694) or a placebo (n = 1,423). Patients were stratified by age group (< 80 years: n = 3,094; ≥ 80 years: n = 1,023).
The estimated median duration of metastasis-free survival in older patients was 40 months with AR inhibitor therapy and 22 months with a placebo (adjusted hazard ratio = 0.37); the median durations of overall survival were 54 and 49 months, respectively (adjusted hazard ratio = 0.79). The estimated median duration of metastasis-free survival in younger patients was longer with AR inhibitor therapy than with a placebo (41 vs. 16 months; adjusted hazard ratio = 0.31); the median durations of overall survival were 74 and 61 months, respectively (adjusted hazard ratio = 0.69).
Among older patients, the rate of grade 3 or higher adverse events was 55% with AR inhibitor therapy and 41% with a placebo; a total of 44% and 30% of younger patients, respectively, experienced grade 3 or higher adverse events. Hypertension and fracture were the most frequently reported grade 3 or 4 adverse events.
“Incorporating geriatric assessment tools in the care of older adults with nonmetastatic castration-resistant prostate cancer might help clinicians to offer individualized treatment to each patient,” the investigators concluded.
Disclosure: The study authors reported no conflicts of interest.