Role of ADT in Efficacy of Docetaxel in Metastatic Castration-Resistant Prostate Cancer
Posted: Tuesday, October 6, 2020
According to the findings of a multicenter randomized phase III study of the Italian Piemonte Oncology Network, the efficacy of docetaxel did not appear to be influenced by the maintenance or suspension of androgen-deprivation therapy (ADT) in patients with metastatic castration-resistant prostate cancer. In fact, the continuous or intermittent schedule of treatment administration also does not appear to play a role in its efficacy. Alfredo Berruti, MD, of Azienda Ospedaliera Spedali Civili di Brescia, Italy, and colleagues presented these results as an e-poster at the European Society for Medical Oncology (ESMO) Virtual Congress 2020 (Abstract 619P).
A total of 198 patients took part in this trial between 2010 and 2014. During the first randomization, approximately half of patients received docetaxel and maintenance with a luteinizing hormone-releasing hormone agonist (LHRH-A), and the others received docetaxel with a suspension of LHRH-A. During the second randomization, patients who were free of disease progression after four cycles of docetaxel received continuous (n = 35) or intermittent (n = 42) docetaxel therapy.
The investigators reported a prostate-specific antigen (PSA) response in 43.8% of those who maintained LHRH-A therapy and 38.2% of those who suspended LHRH-A. For those who maintained LHRH-A therapy, the median progression-free survival was 10.3 months, and the corresponding median overall survival was 23.3 months, compared with 10.8 months and 24.8 months for those who suspended LHRH-A therapy. The hazard ratio for both progression-free survival and overall survival was 1.02, with a P value of .9.
As for toxicity, no differences were noted between the two treatment arms. Serum testosterone levels increased above the castration range after 6 months of therapy in 22.8% of those who maintained therapy with LHRH-A, and normal testosterone levels were reached by 5.9% of those who suspended therapy with LHRH-A after 6 months of therapy.
Disclosure: The study authors reported no conflicts of interest.