News in Prostate Cancer

ASCO 2016. Abstract 5059. Effects of abiraterone (ABI) and enzalutamide (ENZA) on cognitive impairment and depressive symptoms in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC)

Sunil Parimi et al.

Results: 60 pts with a minimum follow-up of 3 months were evaluated: 27 and 33 were randomized to ABI and ENZA,
respectively. 10 were non-evaluable for Montreal Cognitive Association (MoCA) test and 7 for Patient Health Questionnaire (PHQ-9) data. At baseline, median score for MoCA was 25 (range 13-30) and 3 for PHQ-9 (range 0-20). Similar proportions of pts in the ABI and ENZA arms had some baseline impairment in PHQ9 (33.3%, 31.3%) and MoCA scores (76.9%, 74.2%). Change from baseline to Cycle 4 in MoCA and PHQ-9 severity levels are shown in the Table. There was a trend for a greater proportion of pts treated with ENZA as compared to ABI to have a worsening cognitive impairment score (p = 0.20). Significantly more pts in the ENZA arm had a worsening depression severity score (P = 0.03). A greater number of ENZA pts reported worsening on PHQ-9 questions related to energy, appetite, and psychomotor symptoms. 

Conclusions: In this preliminary analysis, there were more pts with a worsening severity of reported depression symptoms and a trend towards an increase in cognitive impairment with ENZA as compared to ABI. These data help to characterize and define the incidence of these symptoms. Clinical trial information: NCT02125357

 CARE™ Faculty Perspective: This study was conducted in Canada and was one of the first head-to-head trials of abiraterone and enzalutamide that compared cognitive impairment and depressive symptoms in patients with metastatic castrate resistant prostate cancer.

With the variety of available agents in this category, we must consider a number of factors to determine which agent to use first,  and which sequence of agents is optimal for a given patient. One of the most important of these factors is toxicity, as side effects of therapy can have a negative impact on patients’ quality of life and their compliance to treatment. From the very preliminary, short term results of this study, it appears that patients who received abiraterone may have had an improvement in overall patient health/depressive symptoms (ie. increased energy, appetite, etc.) and cognitive impairment, compared to enzalutamide.

 While this is an interesting study to consider, data is still early and the sample size was modest.We await further data to verify these findings.