Enzalutamide remains effective, safe at 3 years in hormone-naïve prostate cancer
Treatment with enzalutamide has maintained its antitumour activity in patients with hormone-naïve prostate cancer at 3 years, according to a recent study. In addition, overall bone mineral density, global health status and safety results are comparable to those at 2 years.
None of the patients ceased treatment during year 3. Thirty-eight of 42 patients (90.5 percent; 95 percent CI, 77.4‒97.3) with prostate-specific antigen assessments at 3 years maintained a prostate-specific antigen response. Of 26 patients with metastases at baseline, 17 (65.4 percent) had a complete or partial response as the best overall response during 3 years.
There were minimal mean changes from baseline in total body bone mineral density or bone mineral density of the femoral neck, trochanter, spine L1‒L4, or forearm (range, ‒2.7 to ‒0.1 percent) in patients who completed the 3-year visit.
Total body fat had increased a mean of 16.5 percent, total lean body mass had decreased a mean of ‒6.5 percent, and global health status had minimally decreased from baseline at 3 years. The most frequent adverse events were as follows: fatigue, gynaecomastia, hot flush and nipple pain.
In this study, researchers analysed 67 patients with hormone-naïve prostate cancer and noncastrate testosterone (≥230 ng/dl) who received enzalutamide 160 mg/day orally until disease progression or unacceptable toxicity. Prostate-specific antigen response (≥80 percent decline from baseline) was the primary endpoint.
In a phase II study of enzalutamide monotherapy in patients with hormone-naïve prostate cancer, patients had high prostate-specific antigen response rates at 25 weeks, 1 year and 2 years, with minimal effects on total body bone mineral density and favourable safety, according to researchers.