Background: Prostate cancer (PCa) is the sixth primary cause of cancer death. However,
conflicts are present about the efficacy and safety of Non-steroidal anti-androgens (NSAA) for its
treatment. The aim of this study was to assess the efficacy and safety of NSAAs versus any comparator
for the treatment of advanced or metastatic PCa (mPCa).
Methods: MEDLINE and the Cochrane Library were searched. References of included studies and
clinicaltrials.gov were also searched for relevant studies. Only English language studies after 1990
were considered for review. Randomized controlled trials (RCTs) examining the efficacy and safety
of NSAAs as compared with any other comparator including surgery or chemotherapy in mPCa patients
were included. The outcomes include efficacy, safety and the tolerability of the treatment. The
Cochrane Risk of Bias Assessment Tool was used for quality assessment. Two authors were independently
involved in the selection, extraction and quality assessment of included studies and disagreements
were resolved by discussion or by consulting a third reviewer.
Results: Fifty-eight out of 1307 non-duplicate RCTs with 29154 patients were considered for the review.
NSAA showed significantly better progression-free survival [PFS] (Hazard ratio [HR], 0.60;
95% confidence interval [CI], 0.46-0.78; P=0.0001), time to distant metastasis or death [TTD] (HR,
0.80; 95% CI 0.73-0.91; P<0.0001), objective response (Odds ratio [OR], 1.64; 95% CI 1.06-2.54;
P=0.03) and clinical benefits (OR, 1.33; 95% CI 1.08-1.63; P=0.006) as compared to the control
group. There was no significant difference observed between the groups in terms of overall survival
(HR, 0.95; 95%CI, 0.87-1.03; P=0.18) and time to progression (HR, 0.93; 95% CI 0.77-1.11;
P=0.43). Treatment-related adverse events were more with the NSAA group, but the discontinuation
due to lack of efficacy reason was 43% significantly lesser than the control group in patients with
mPCa. Rest of the outcomes were appeared to be non-significant.
Conclusion: Treatment with NSAA was appeared to be better efficacious with respect to PFS, TTD,
and response rate with considerable adverse events when compared to the control group in patients
with metastatic PCa.