Enzalutamide treatment in patients with metastatic castration-resistant prostate cancer progressing after chemotherapy and abiraterone acetate

TY - JOUR

T1 - Enzalutamide treatment in patients with metastatic castration-resistant prostate cancer progressing after chemotherapy and abiraterone acetate

AU - Thomsen, Frederik Birkebaek

AU - Røder, Martin Andreas

AU - Rathenborg, Per

AU - Brasso, Klaus

AU - Borre, Michael

AU - Iversen, Peter

PY - 2014/6

Y1 - 2014/6

N2 - OBJECTIVE: The aim of this study was to record prostate-specific antigen (PSA) response and overall survival (OS) for a group of metastatic castration-resistant prostate cancer (mCRPC) patients treated with enzalutamide following progression after abiraterone treatment in the post-chemotherapy setting.MATERIAL AND METHODS: Twenty-four mCRPC patients with progression after abiraterone treatment following primary docetaxel therapy received enzalutamide 160 mg/day. The percentage PSA response was recorded following first line docetaxel, abiraterone and enzalutamide treatment. Fischer's exact test, Mann-Whitney U test and linear regression model were used to test for differences in PSA response.RESULTS: All patients had a follow-up of at least 3 months. The median PSA response following 1 month of enzalutamide was -12% (range -56% to 76%), while the median best PSA response was -22% (-76% to 76%). Forty-six percent had a greater than 30% decrease in PSA. The PSA response to enzalutamide did not correlate with the number of prior cancer treatments (p = 0.57), time from diagnosis to mCRPC (p = 0.11) or prior response to docetaxel (p = 0.67). However, patients treated with second line cabazitaxel had an inferior PSA response to enzalutamide (p = 0.03), and there was a trend for the PSA response to abiraterone to correlate with the PSA response to the succeeding enzalutamide (B = 0.22, p = 0.05). The median OS was 4.8 months.CONCLUSIONS: Previous abiraterone therapy is associated with a less marked fall in PSA following enzalutamide therapy in post-chemotherapy mCRPC patients compared with reported results in randomized trials. Larger prospective studies of sequencing are warranted.

AB - OBJECTIVE: The aim of this study was to record prostate-specific antigen (PSA) response and overall survival (OS) for a group of metastatic castration-resistant prostate cancer (mCRPC) patients treated with enzalutamide following progression after abiraterone treatment in the post-chemotherapy setting.MATERIAL AND METHODS: Twenty-four mCRPC patients with progression after abiraterone treatment following primary docetaxel therapy received enzalutamide 160 mg/day. The percentage PSA response was recorded following first line docetaxel, abiraterone and enzalutamide treatment. Fischer's exact test, Mann-Whitney U test and linear regression model were used to test for differences in PSA response.RESULTS: All patients had a follow-up of at least 3 months. The median PSA response following 1 month of enzalutamide was -12% (range -56% to 76%), while the median best PSA response was -22% (-76% to 76%). Forty-six percent had a greater than 30% decrease in PSA. The PSA response to enzalutamide did not correlate with the number of prior cancer treatments (p = 0.57), time from diagnosis to mCRPC (p = 0.11) or prior response to docetaxel (p = 0.67). However, patients treated with second line cabazitaxel had an inferior PSA response to enzalutamide (p = 0.03), and there was a trend for the PSA response to abiraterone to correlate with the PSA response to the succeeding enzalutamide (B = 0.22, p = 0.05). The median OS was 4.8 months.CONCLUSIONS: Previous abiraterone therapy is associated with a less marked fall in PSA following enzalutamide therapy in post-chemotherapy mCRPC patients compared with reported results in randomized trials. Larger prospective studies of sequencing are warranted.

KW - Aged

KW - Androstadienes

KW - Antineoplastic Agents

KW - Cohort Studies

KW - Compassionate Use Trials

KW - Disease-Free Survival

KW - Humans

KW - Kallikreins

KW - Linear Models

KW - Male

KW - Middle Aged

KW - Phenylthiohydantoin

KW - Prostate-Specific Antigen

KW - Prostatic Neoplasms, Castration-Resistant

KW - Taxoids

KW - Treatment Failure

KW - Treatment Outcome

U2 - 10.3109/21681805.2013.860189

DO - 10.3109/21681805.2013.860189

M3 - Journal article

C2 - 24255983

SN - 0036-5599

VL - 48

SP - 268

EP - 275

JO - Scandinavian Journal of Urology and Nephrology

JF - Scandinavian Journal of Urology and Nephrology

IS - 3

ER -