1801P - Impact of intensified androgen deprivation therapy (ADTi) in the metastatic castration-sensitive prostate cancer (mCSPC) setting on metastatic castration-resistant prostate cancer (mCRPC) disease characteristics and survival outcomes

Background

ADTi is the standard of care treatment (Rx) for mCSPC. We hypothesized that pts who received ADTi in mCSPC and progressed to mCRPC would have different disease characteristics and survival than those treated with ADT monotherapy (ADTm) in the mCSPC setting.

Methods

After IRB approval, patient (pt)-level data were collected retrospectively. Eligibility: confirmed diagnosis of mCRPC, treated with 1L approved Rx with follow up data available. Pts were stratified based on whether they received ADTi (docetaxel or novel hormonal therapies) or ADTm in the mCSPC setting. Study endpoints: Progression-free survival (PFS) as and overall survival (OS) from time of mCRPC diagnosis. A multivariate analysis using the Cox proportional hazards model was used adjusting for potential confounders.

Results

519 consecutive pts (368 ADTm and 151 ADTi) seen at our institution between 2009 to 2022 were eligible. mCRPC pts who received ADTi compared to ADTm had lower PSA (10.3 vs. 21.5 ng/ml, P = 0.002), more visceral metastases (20.5 vs. 11.1%, P = 0.005), higher alkaline phosphatase (110.5 vs. 96 U/L, P = 0.034); and had worse median PFS (5.3 vs. 8.6 months, P < 0.001) and OS (21.2 vs. 31.7 months, P < 0.001) compared to those with ADTm in both univariate and multivariate analysis (Table).

Table: 1801P

Conclusions

In the era of ADTi for mCSPC, the survival outcomes in the mCRPC is poorer compared to those in the era of ADTm for mCSPC. These hypothesis-generating data may aid patient counseling, prognostication, and clinical trial design in mCRPC in the current era.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

B.L. Maughan: Financial Interests, Personal and Institutional, Advisory Board, paid consultant/advisor to AbbVie, Pfizer, AVEO oncology, Janssen, Astellas, BMS, Clovis, Tempus, Merck, Exelixis, Bayer Oncology and Peloton Therapeutics; Huntsman Cancer Institute has received research funding from Exelixis (Inst), Bavarian-Nordic (Inst), Clovis (Inst), Genentech (Inst) and BMS (Inst) on his behalf: paid consultant/advisor to AbbVie, Pfizer, AVEO oncology, Janssen, Astellas, BMS, Clovis, Tempus, Merck, Exelixis, Bayer Oncology and Peloton Therapeutics; Huntsman Cancer Institute has received research funding from Exelixis (Inst), Bav. N. Agarwal: Financial Interests, Personal and Institutional, Advisory Board, Consultancy to Astellas, AstraZeneca, Aveo, Bayer, BMS, Calithera, Clovis, Eisai, Eli Lilly, EMD Serono, Exelixis, Foundation Medicine, Genentech, Gilead, Janssen, Merck, MEI Pharma, Nektar, Novartis, Pfizer, Pharmacyclics, and Seattle Genetics. Research funding to Neeraj Agarwal's institution: Arnivas, Astellas, AstraZeneca, Bavarian Nordic, Bayer, BMS, Calithera, Celldex, Clovis, Crispr, Eisai, Eli Lilly, EMD Serono, Exelixis, Genentech, Gilead, GSK, Immunomedics, Janssen, Lava, Medivation, Merck, Nektar, Neoleukin, New Link Genetics, Novartis, Oric, Pfizer, Prometheus, Rexahn, Roche, Sanofi, Seattle Genetics, Takeda, and Tracon: Consultancy to Astellas, AstraZeneca, Aveo, Bayer, BMS, Calithera, Clovis, Eisai, Eli Lilly, EMD Serono, Exelixis, Foundation Medicine, Genentech, Gilead, Janssen, Merck, MEI Pharma, Nektar, Novartis, Pfizer, Pharmacyclics, and Seattle G. U. Swami: Financial Interests, Personal and Institutional, Advisory Board, a consulting or advisory role by Seattle Genetics, Astellas Pharma, Exelixis, Imvax, and AstraZeneca, currently or during the past 2 years. Dr. Swami’s institution has received research funding from Janssen, Seattle Genetics/Astellas, and Exelixis, currently or within the past 2 years: a consulting or advisory role by Seattle Genetics, Astellas Pharma, Exelixis, Imvax, and AstraZeneca, currently or during the past 2 years. Dr. Swami’s institution has received research funding from Janssen, Seattle Genetics/Astellas, and Exelixis, curren. All other authors have declared no conflicts of interest.