Hammerer P, et al. - The intent of the authors was to gauge the tie-up between prostate-specific antigen (PSA) response and progression-free and overall survival in men with metastatic castration-resistant prostate cancer (mCRPC) treated with cabazitaxel. Results shed light on the connection between PSA response after four cycles of cabazitaxel with improved progression-free survival in patients treated with cabazitaxel plus prednis(ol)one.

Methods

• Researchers of the non-interventional, prospective QoLiTime study, recruited men with mCRPC receiving cabazitaxel (25 mg/m², every 3 weeks) plus oral prednis(ol)one (10 mg/day).
• Main outcome measures included the progression-free survival and overall survival, in all patients and in those who displayed a ≥ 50 or a ≥ 30% decrease in PSA relative to baseline after four cycles of cabazitaxel, along with the quality-of-life parameters.

Results

• Among the 527 men (median age 72 years), 266 received ≥ 4 cycles of cabazitaxel and exhibited PSA response data.
• It was found that 34.6% of men achieved a PSA decrease ≥ 50% and 49.6% a decrease ≥ 30% after four cycles.
• Data revealed that the median progression-free survival was 7.7 (95% CI 6.2, 9.5) months, and overall survival was 19.5 (95% CI 16.0, 30.9) months, corresponding to 1-year event rates of 39.4 and 78.8%, respectively.
• Longer median progression-free survival was detrmined in PSA responders when compared to the non-responders (15.7 vs 5.5 months at 50% cut-off; 15.7 vs 5.3 months for 30% cut-off; both P < 0.0001).
• Furthermore, the overall survival (50% cut-off) was found to be 23.3 months in responders and 16.0 months in non-responders (P=0.068).
• Results illustrated the corresponding data at the 30% cut-off as 21.7 and 16.0 months (P=0.057).
• Herein, ≥ 1 adverse event/s were experienced by 55.4% of men, 59.6% of whom reported a serious adverse event.