New study below.
"Abiraterone acetate {Zytiga, Abi} received licencing for use in only "high-risk" metastatic hormone-naïve prostate cancer (mHNPC) following the LATITUDE trial findings."
"However, a "risk"-related effect was not seen in the STAMPEDE trial." "A total of 901 M1 STAMPEDE patients were evaluated after exclusions. Of the patients, 428 (48%) were identified as having a low risk and 473 (52%) a high risk."
"Patients receiving ADT + AAP had significantly improved OS {overall survival} (low-risk hazard ratio [HR]: 0.66 ... compared with ADT alone."
"Heterogeneity of effect was not seen between low- and high-risk groups for OS ..."
"For OS benefit in low risk, the number needed to treat was four times greater than that for high risk."
"Men with mHNPC gain treatment benefit from ADT + AAP irrespective of risk stratification for "risk" or "volume"."
***
Once again the term "ADT" is used to mean (post-DES) classic ADT. Abi is clearly a form of ADT, & could be used as such without the need for classic ADT. No doubt someone will come up with a better retronym than "classic ADT". "Castration therapy" would perhaps be clearer.
The term CRPC (castrate-resistant PCa) is clear enough, but what is the term for failing Abi monotherapy or Abi+classic ADT?
-Patrick
[1] ncbi.nlm.nih.gov/pubmed/314...
Eur Urol. 2019 Aug 22. pii: S0302-2838(19)30620-7. doi: 10.1016/j.eururo.2019.08.006. [Epub ahead of print]
Abiraterone in "High-" and "Low-risk" Metastatic Hormone-sensitive Prostate Cancer.
Hoyle AP1, Ali A2, James ND3, Cook A4, Parker CC5, de Bono JS5, Attard G6, Chowdhury S7, Cross WR8, Dearnaley DP9, Brawley CD4, Gilson C4, Ingleby F5, Gillessen S10, Aebersold DM11, Jones RJ12, Matheson D13, Millman R14, Mason MD15, Ritchie AWS5, Russell M12, Douis H3, Parmar MKB4, Sydes MR4, Clarke NW16; STAMPEDE Investigators.
Author information
1
The Christie and Royal Salford Hospitals, Manchester, UK; Genito Urinary Cancer Research Group and the FASTMAN Centre of Excellence, Division of Cancer Sciences, The University of Manchester, Manchester, UK.
2
The Christie and Royal Salford Hospitals, Manchester, UK.
3
Institute of Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham, UK.
4
MRC Clinical Trials Unit at UCL, Institute of Clinical Trials and Methodology, UCL, London, UK.
5
Royal Marsden Hospital, Sutton, UK.
6
UCL Cancer Institute, University College London, London, UK.
7
Guy's & St Thomas NHS Foundation Trust, London, UK.
8
St James University Hospital, Leeds, UK.
9
Institute of Cancer Research, Sutton, UK.
10
Division of Oncology and Haematology, Kantonsspital St. Gallen, St. Gallen, Switzerland; Christie Hospital, Manchester, UK; University of Manchester, Manchester, UK; Swiss Group for Cancer Clinical Research (SAKK), Bern, Switzerland.
11
Department of Radiation Oncology, Bern University Hospital, Switzerland.
12
Institute of Cancer Sciences, University of Glasgow, Glasgow, UK; Beatson West of Scotland Cancer Centre, University of Glasgow, Glasgow, UK.
13
Northampton, UK.
14
Stockton-on-Tees, UK.
15
University of Cardiff, Cardiff, UK.
16
The Christie and Royal Salford Hospitals, Manchester, UK; Genito Urinary Cancer Research Group and the FASTMAN Centre of Excellence, Division of Cancer Sciences, The University of Manchester, Manchester, UK. Electronic address: noel.clarke@christie.nhs.uk.
Abstract
BACKGROUND:
Abiraterone acetate received licencing for use in only "high-risk" metastatic hormone-naïve prostate cancer (mHNPC) following the LATITUDE trial findings. However, a "risk"-related effect was not seen in the STAMPEDE trial. There remains uncertainty as to whether men with LATITUDE "low-risk" M1 disease benefit from androgen deprivation therapy (ADT) combined with abiraterone acetate and prednisolone (AAP).
OBJECTIVE:
Evaluation of heterogeneity of effect between LATITUDE high- and low-risk M1 prostate cancer patients receiving ADT + AAP in the STAMPEDE trial.
DESIGN, SETTING, AND PARTICIPANTS:
A post hoc subgroup analysis of the 2017 STAMPEDE "abiraterone comparison". Staging scans for M1 patients contemporaneously randomised to ADT or ADT + AAP within the STAMPEDE trial were evaluated centrally and blind to treatment assignment. Stratification was by risk according to the criteria set out in the LATITUDE trial. Exploratory subgroup stratification incorporated the CHAARTED criteria.
OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS:
The primary outcome measure was overall survival (OS) and the secondary outcome measure was failure-free survival (FFS). Further exploratory analysis evaluated clinical skeletal-related events, progression-free survival (PFS), and prostate cancer-specific death. Standard Cox-regression and Kaplan-Meier survival estimates were employed for analysis.
RESULTS AND LIMITATIONS:
A total of 901 M1 STAMPEDE patients were evaluated after exclusions. Of the patients, 428 (48%) were identified as having a low risk and 473 (52%) a high risk. Patients receiving ADT + AAP had significantly improved OS (low-risk hazard ratio [HR]: 0.66, 95% confidence interval or CI [0.44-0.98]) and FFS (low-risk HR: 0.24, 95% CI [0.17-0.33]) compared with ADT alone. Heterogeneity of effect was not seen between low- and high-risk groups for OS or FFS. For OS benefit in low risk, the number needed to treat was four times greater than that for high risk. However, this was not observed for the other measured endpoints.
CONCLUSIONS:
Men with mHNPC gain treatment benefit from ADT + AAP irrespective of risk stratification for "risk" or "volume".
PATIENT SUMMARY:
Coadministration of abiraterone acetate and prednisolone with androgen deprivation therapy (ADT) is associated with prolonged overall survival and disease control, compared with ADT alone, in all men with metastatic disease starting hormone therapy for the first time.
Copyright © 2019. Published by Elsevier B.V.
KEYWORDS:
Abiraterone; Adjuvant treatment; Advanced; Androgen deprivation therapy; Hormone-naïve prostate cancer; Hormone-sensitive prostate cancer; Metastatic; Prostate cancer; STAMPEDE trial; Systemic therapy
PMID: 31447077 DOI: 10.1016/j.eururo.2019.08.006