Enzalutamide monotherapy: One-year extended follow-up of a phase 2 study in hormone-naive prostate cancer patients.

Konference: 2014 50th ASCO Annual Meeting - účast ČR

Kategorie: Genitourinární nádory

Téma: Postery

Číslo abstraktu: 5068

Autoři: Prof. M.D. Bertrand F. Tombal, Ph.D.; Prof. M.D. Michael Borre; M.D. Per Rathenborg; M.D. Patrick Werbrouck; Prof. M.D. Hendrik Van Poppel; Prof. M.D. Axel Heidenreich; Peter Iversen; M.D. Johan Braeckman; Doc. MUDr. Jiří Heráček, Ph.D.; M.D. Edwina Baskin-Bey; Taoufik Ouatas; M.D. Frank Perabo; De Phung; M.D. Mohammad Hirmand; M.D. Matthew Raymond Smith, Ph.D.

Abstract:

Background: The efficacy and safety of enzalutamide monotherapy was assessed in men with any-stage hormone-naive prostate cancer eligible for androgen-deprivation therapy (ADT). The primary endpoint of PSA response rate (≥80% PSA decrease between baseline and week 25) was 92.5% (Smith M et al, ASCO 2013). The median (range) maximum PSA decline from baseline to week 25 was –99.6% (–100, –86.5). 1-year extended follow-up data are presented. 

Methods: In an open-label, single-arm Phase 2 study (NCT01302041), men ≥18 years with histologically confirmed prostate cancer requiring ADT, non-castrate testosterone (≥8 nmol/L), PSA ≥2 ng/mL at screening, and a life expectancy of ≥12 months, received 160 mg enzalutamide once daily until disease progression or unacceptable toxicity. Other endpoints included changes in hormone levels, metabolic parameters, BMD, safety, and quality of life (QoL). 

Results: 67 men were enrolled. Median (range) age was 73 years (48–86); 38.8% had metastases; 35.8% and 23.9% had undergone prior prostatectomy and radiotherapy, respectively. 54 men (80.6%) completed 1 year of treatment with a PSA response rate of 100% and 53 (98.1%) had ≥90% PSA decrease from baseline. The median (range) maximum decline in PSA was –100% (–100, –86.5) from baseline to 1 year. Luteinizing hormone and testosterone were increased from baseline by 215.2% and 101.7%, respectively. Mean changes from baseline for fasting metabolic variables were: +5.0% total cholesterol, +8.9% triglycerides, –3.5% HbA1c, and +19.7% insulin resistance (HOMA-IR). Total body BMD was maintained (–0.3% from baseline). The most frequently reported treatment-emergent AEs were gynecomastia (47.8%) and fatigue (38.8%). Seven non-drug-related serious AEs were reported. Qol scores at 1 year demonstrate maintenance of global health status and a decrease in sexual activity and sexual functioning. 

Conclusions: Extended follow-up of hormone-naive patients demonstrated sustained PSA reductions up to 1 year of enzalutamide monotherapy. Endocrine and metabolic changes, and AEs were consistent with potent AR inhibition and similar to results reported at 25 weeks. Clinical trial information: NCT01302041.

www.asco.org

Citation:
J Clin Oncol 32:5s, 2014 (suppl; abstr 5068)

Datum přednesení příspěvku: 2. 6. 2014