165P - Real-world utilisation of upfront chemohormonal therapy in metastatic hormone-sensitive prostate cancer

Background

The addition of docetaxel to androgen deprivation therapy (ADT) for metastatic hormone sensitive prostate cancer (mHSPC) has demonstrated significant overall survival (OS) benefit. We aimed to evaluate the real-world utilisation rates of upfront docetaxel and associated patient outcomes in Australia.

Methods

The electronic CRPC Australian Database (ePAD) was interrogated to identify patients diagnosed with mHSPC between July 2015 and July 2021. Clinicopathological features, treatment and outcome data, stratified by treatment with upfront docetaxel, were analysed through descriptive statistics. Survival analyses were calculated using the Kaplan-Meier method and groups compared using log-rank tests.

Results

We identified 324 mHSPC patients with median age 69.8 years and median follow up 32.6 months. 152 (47%) received upfront docetaxel. 129 patients (85%) completed ≥6 cycles of docetaxel. Rates of docetaxel use were stable across a 6-year period (48% in 2015, 50% in 2021). Patients treated with docetaxel were significantly younger (mean 66 vs 74 years, p=<0.001) and significantly less likely to have cognitive impairment (p=0.03). Rates of docetaxel administration were similar in those with visceral metastases (22 patients, 60%) and synchronous mHSPC (139 patients, 49%) to the total cohort (47%). Median time to castration-resistance was 12.0 months for the entire cohort and 11.6 months in the docetaxel group. Median OS was not reached for either group. For the docetaxel group, OS was 99%, 87% and 72% at 12, 24 and 36 months respectively. There was no statistical difference in OS between those treated with upfront docetaxel vs ADT alone in the entire population (p=0.94) or those patients with synchronous mHSPC (p=0.95). There was a trend toward higher OS at 36 months in those with locoregional vs visceral metastases (77% vs 52%) and metachronous vs synchronous mHSPC (85% vs 72%). Multivariate analyses will be presented.

Conclusions

Our results reflect the underutilisation of docetaxel in the real-world setting. Both efficacy and utilisation rates were consistent with prior literature. Further studies regarding the influence of patient selection and the availability of novel antiandrogens are needed.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Walter and Eliza Hall Institute (WEHI).

Funding

Astellas, Amgen, AstraZeneca, Bayer, Janssen and MSD.

Disclosure

A. Azad: Financial Interests, Personal and Institutional, Research Grant: Astellas, Merck Serono, AstraZeneca, Pfizer, Novartis, Ipsen, Exelicis, Merck Sharpe Dome, Janssen; Financial Interests, Institutional, Research Grant: Bristol Myers Squibb, Aptevo therapeutics, Glaxo Smith Kline, MedImmune, SYNthorx, Bionomics, Sanofi Aventis, Eli Lilly, Gilead Sciences; Financial Interests, Personal, Invited Speaker: Bayer, Amgen, Noxopharm, Aculeus Therapeutics. F. Parnis: Financial Interests, Personal, Advisory Board: Janssen; Financial Interests, Personal, Invited Speaker: Bayer, AstraZeneca. E. Kwan: Financial Interests, Personal and Institutional, Research Grant: Astellas Pharma; Financial Interests, Personal, Invited Speaker: Janssen, Ipsen, Roche, Research Review; Financial Interests, Personal, Funding: Pfizer. C. Steer: Financial Interests, Personal, Invited Speaker: Janssen, MSD, Merck, AstraZeneca, GSK, Sanofi, Eisai, Specialised therapeutics. A. Anton: Financial Interests, Personal, Invited Speaker: Amgen, Janseen; Financial Interests, Institutional, Research Grant: Mundipharma, Astellas, Amgen, AstraZeneca, Bayer, Janssen. B. Tran: Financial Interests, Personal and Institutional, Research Grant: Amgen, Astellas, AstraZeneca, Bayer, BMS, Ipsen, Janssen, Pfizer, MSD; Financial Interests, Institutional, Research Grant: Genetech, Movember; Financial Interests, Personal, Advisory Board: IQVIA, Novartis, Roche, Sanofi, Tolmar; Financial Interests, Personal, Invited Speaker: Merck. All other authors have declared no conflicts of interest.