Background Enzalutamide (ENZ) and abiraterone acetate (AA) are oral treatments indicated for metastatic castration-resistant prostate cancer (mCPRC). Both drugs can cause neurological and psychiatric adverse effects. Some publications suggest that some neuropsychiatric adverse reactions are more frequent with ENZ than with AA.

Purpose The aim of this study was to check the prevalence of these types of adverse reactions in patients treated in our hospital, by reviewing their clinical history.

Material and methods We selected those patients in treatment with ENZ or with AA in our hospital from January 2015 to September 2018. Clinical data were obtained by consulting their clinical history and the pharmacy service’s computer program. The presence of any of these signs/symptoms was identified as adverse neuropsychiatric reaction: restless leg syndrome, anxiety, headache, insomnia, seizures, falls, dizziness, hallucinations, memory impairment.

Results During the study period, 53 patients received treatment with abiraterone and 61 patients received treatment with enzalutamide. The mean age was over 60 years in both groups. In the AA group, 12 patients (22.6%) with adverse neuropsychiatric-type reactions were detected: falls (eight patients), insomnia (six patients), headache (six patients) and memory loss (four patients). The ENZ group showed similar data, in 14 patients these types of alterations appeared (22.9%): insomnia (10 patients), headache (six patients), falls (six patients) and memory loss (five patients).

Conclusion After evaluating our results, it could be concluded that both abiraterone and enzalutamide show the same profile in terms of adverse neuropsychiatric reactions. But it is true that more studies are required to determine if these reactions are due to these drugs or to other factors such as age, the evolution of the disease or the patient’s social situation.

References and/or acknowledgements 1. J Clin Oncol201836: (suppl 6S; abstr 217).

No conflict of interest.