1500 - Retrospective evaluation of neutropenic admission events in metastatic or high-risk hormone-sensitive prostate cancer (HSPC) patients having docetaxel chemotherapy upfront or for castrate-resistant prostate cancer (CRPC) in STAMPEDE

Background

Docetaxel (Doc) was initially licenced for CRPC (TAX327) but more recently trials showed Doc at HSPC diagnosis improved survival, shifting patterns of use. Higher neutropenic toxicity rates were reported in the HSPC trials, but it is unclear if this was due to the Doc timing or differences in case-mix. We compared sepsis rates for Doc at HSPC and CRPC using routine NHS data for men randomised in STAMPEDE in England.

Methods

STAMPEDE patient data were linked to routine NHS data (Hospital Episode Statistics: HES; Systemic Anti-Cancer Therapy: SACT). Patient note review (ref) linked to NHS data assessed admission rates by HSPC & CRPC Doc at 1 site (N = 44) and were used to develop and validate algorithms for detecting sepsis events across the entire data set. Algorithms were restricted to sepsis-only & sepsis + neutropenia (S+N) (N = 3645). Missing HES CRPC Doc regimens were imputed with HES (N = 3645) or enhanced with SACT (N = 1573). Odds ratios (OR) were calculated for risk of sepsis (OR < 1 = lower risk for HSPC).

Results

Sepsis rates varied by method; for most, rates at CRPC were higher than in TAX327 but similar to or higher than reported STAMPEDE HSPC data.Table:

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Conclusions

This analysis does not support the hypothesis that HSPC Doc has a higher sepsis risk than Doc use in CRPC. Sepsis rates found using routine data were higher than in the TAX327 trial but similar to reported “real world” CRPC data. Rates varied by data-identification method used; for most, CRPC sepsis rates were higher or similar to HSPC rates & overall a little higher than the reported STAMPEDE HSPC rate. These data suggest CRPC Doc has a similar or higher sepsis rate than use in HSPC & this should be factored into discussions for men with newly-diagnosed metastatic HSPC and supports Doc use in this setting.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The STAMPEDE Trial Group.

Funding

University of Warwick, Warwick Medical School (HM PhD studentship).

Disclosure

M.K.B. Parmar: Research grant / Funding (institution): Astellas Pharma; Research grant / Funding (institution): Clovis oncology; Research grant / Funding (institution): Novartis; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Sanofi; Research grant / Funding (institution), The Unit I am Director of also receives educational grants and other non- financial support from a large number of different companies: Other. P. Patel: Advisory / Consultancy: Roche/Genentech. M.R. Sydes: Honoraria (self): Lilly; Honoraria (self), Research grant / Funding (self): Sanofi; Honoraria (self): Janssen; Research grant / Funding (self): Astellas Pharma; Research grant / Funding (self): Janssen-Cilag; Research grant / Funding (self): Pfizer; Research grant / Funding (self): Novartis; Research grant / Funding (self): Clovis Oncology. N.D. James: Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution), Travel / Accommodation / Expenses: Sanofi; Honoraria (self), Advisory / Consultancy: Bayer; Advisory / Consultancy: Merck; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Astellas Pharma; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Janssen; Honoraria (self), Speaker Bureau / Expert testimony: Pierre Fabre; Speaker Bureau / Expert testimony: Ferring; Honoraria (self): Oncogenex; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Novartis. All other authors have declared no conflicts of interest.