Bipolar Androgen Therapy Versus Enzalutamide in Castration-Resistant Prostate Cancer
Posted: Wednesday, May 5, 2021
According to results from the phase II TRANSFORMER trial presented in the Journal of Clinical Oncology, bipolar androgen therapy may be a safe and clinically active treatment option for men with castration-resistant metastatic prostate cancer. This rapid cycling between high and low serum testosterone may increase sensitivity to subsequent antiandrogen therapy, such as enzalutamide, proposed Emmanuel S. Antonarakis, MD, of the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, and colleagues.
“Although the trial failed to demonstrate superior [progression-free survival] with [bipolar androgen therapy] over enzalutamide in post-abiraterone [castration-resistant prostate cancer], it demonstrated that [bipolar androgen therapy] is safe, enhances [quality of life], and has efficacy comparable to enzalutamide in this patient population,” the investigators concluded.
The study included 195 patients randomly assigned to receive either bipolar androgen therapy (n = 94) or enzalutamide (n = 101) monthly. Both groups experienced a median progression-free survival of 5.7 months. A similar percentage of patients receiving bipolar antigen therapy had a 50% decline in prostate-specific antigen (PSA) values as those receiving enzalutamide (28.2% vs. 25.3%). Median overall survival was 32.9 months with bipolar androgen therapy versus 29.0 months with enzalutamide. Patient-reported quality of life was superior in the group given bipolar androgen therapy, where adverse events were mostly grade 1 or grade 2.
Patients were allowed to switch treatments at disease progression. For patients crossing over from bipolar androgen therapy to enzalutamide, median overall survival was 32.9 months, and median progression-free survival was 28.2 months. For those making the reverse trade, those survival outcomes were 30.2 months and 19.6 months, respectively. The median time to PSA disease progression increased from 3.8 months after abiraterone to 10.9 months after patients switched from receiving bipolar androgen therapy in the enzalutamide group.
Disclosure: For full disclosures of the study authors, visit ascopubs.org.
