Written by Dr. Roupen Odabashian MD, FRCPC
Oncologist | Founder, MeDucation AI | Updated October 2026
STAMPEDE is a multi-arm, multi-stage platform trial that enrolled men starting first-line long-term androgen deprivation therapy (ADT) for high-risk, locally advanced, or metastatic prostate cancer, and tested multiple additions to standard of care against a shared control group over two decades[1][2]. The headline results changed practice three times: docetaxel added to ADT improved overall survival[2], abiraterone added to ADT improved overall survival[3][4], and prostate radiotherapy added to ADT improved overall survival, but only in men with low metastatic burden[5]. If you take one thing into the exam room, it is that STAMPEDE is why docetaxel and abiraterone are now routine at the start of treatment for many men, not reserved for later lines.
Ranked summary: which STAMPEDE finding matters most for practice and boards
Rank | Addition to ADT | Population | Survival effect | Practice status |
|---|---|---|---|---|
1 | Abiraterone acetate + prednisolone | High-risk, starting long-term ADT (locally advanced or metastatic) | 37% relative reduction in risk of death[3] | Standard of care addition[3][4] |
2 | Docetaxel + prednisolone | Starting long-term ADT, high-risk non-metastatic or metastatic[1] | Improved overall survival vs SOC alone[2] | Standard of care addition in suitable, fit patients[1][2] |
3 | Radiotherapy to the prostate | Newly diagnosed metastatic, low metastatic burden only | 32% relative improvement in overall survival in low-burden subgroup[5] | Standard option for low-burden oligometastatic disease[5] |
5 | Celecoxib | Starting long-term ADT | No survival benefit reported[1] | Not adopted[1] |
What is the STAMPEDE trial, exactly?
STAMPEDE stands for Systemic Therapy in Advancing or Metastatic Prostate Cancer: Evaluation of Drug Efficacy, and it is a single platform trial, not a series of separate studies[1]. Recruitment ran across 117 hospitals in the UK and Switzerland, started in 2005, ended in 2022, and had enrolled over 10,000 participants by January 2020[1]. Men beginning lifelong ADT for the first time, whether for high-risk locally advanced, node-positive, or metastatic disease, were randomly assigned to standard of care alone or standard of care plus one of a growing list of additional interventions[1][2]. The primary outcome across the platform was overall survival[1].
What arms were actually tested?
Over its lifespan STAMPEDE ran arms testing docetaxel, zoledronic acid, celecoxib, abiraterone with prednisolone, radiotherapy, combined abiraterone and enzalutamide, metformin, and transdermal oestradiol in place of standard ADT, all compared against a common control arm of standard of care[1]. The design let the trial retire arms that did not work and add new ones without starting from zero each time, which is the specific innovation this section is going to unpack next.
What did STAMPEDE find for docetaxel?
Adding docetaxel to long-term hormone therapy improved overall survival, and that result has held up as one of the most practice-changing findings in prostate cancer in the past decade[2][4]. In the docetaxel, zoledronic acid comparison, 2,962 men were randomized between October 2005 and March 2013 to standard of care alone, standard of care plus zoledronic acid, standard of care plus docetaxel, or standard of care plus both[2]. Docetaxel was dosed at 75 mg/m2 for six 3-weekly cycles with daily prednisolone 10 mg[2].
Arm | Median overall survival | Hazard ratio vs SOC alone | p-value |
|---|---|---|---|
SOC alone | 71 months[2] | reference | - |
SOC + zoledronic acid | Not reached[2] | 0.94 (0.79 to 1.11)[2] | 0.450 |
SOC + docetaxel | 81 months[2] | 0.78 (0.66 to 0.93)[2] | 0.006 |
SOC + docetaxel + zoledronic acid | 76 months[2] | 0.82 (0.69 to 0.97)[2] | 0.022 |
Median follow-up was 43 months, with 415 deaths recorded in the control group, 84% of them attributed to prostate cancer[2]. Grade 3-5 adverse events were more frequent with docetaxel: 52% in the docetaxel-containing arms versus 32% with standard of care or zoledronic acid alone[2]. The trial's own interpretation was direct: zoledronic acid showed no survival benefit and should not be part of standard of care, while docetaxel given at the start of long-term hormone therapy showed a clear survival benefit and should become standard of care for adequately fit men[2].
What did STAMPEDE find for abiraterone?
Adding abiraterone acetate and prednisolone to standard therapy at the start of ADT lowered the relative risk of death by 37% in the pivotal STAMPEDE analysis[3]. This analysis, presented at the 2017 ASCO Annual Meeting, compared standard therapy with standard therapy plus abiraterone in men with high-risk prostate cancer, locally advanced or metastatic, who were starting long-term ADT for the first time[3]. At a median follow-up of 40 months, there were 262 deaths in the standard therapy group versus 184 in the abiraterone group[3].
Outcome | Standard therapy | Standard therapy + abiraterone |
|---|---|---|
3-year overall survival | 76% | 83%[3] |
Relative risk of treatment failure | reference | 71% lower[3] |
What did STAMPEDE find for prostate radiotherapy in metastatic disease?
Radiation to the primary prostate tumor improved overall survival only in men with a low burden of metastatic disease, not in the overall trial population[5]. This analysis included 2,061 men newly diagnosed with metastatic prostate cancer, randomized to standard of care with or without early docetaxel, with or without radiotherapy to the prostate[5]. Metastatic burden was classified as low in 40% and high in 54% of patients, using a definition in which high burden meant 4 or more bone metastases with at least one outside the axial skeleton, visceral metastases, or both[5].
Population | Arm | 3-year overall survival | Statistical significance |
|---|---|---|---|
Whole trial population | Control | 62%[5] | - |
Whole trial population | + Radiotherapy | 65%[5] | not statistically significant overall (HR 0.92, 95% CI 0.80 to 1.06)[8] |
Low metastatic burden | Control | 73%[8] | - |
Low metastatic burden | + Radiotherapy | 81%[8] | significant (HR 0.68, 95% CI 0.52 to 0.90)[8] |
High metastatic burden | Control | 54%[8] | - |
High metastatic burden | + Radiotherapy | 53%[8] | no benefit (HR 1.07, 95% CI 0.90 to 1.28)[8] |
Radiotherapy was also well tolerated, with grade 3 or 4 adverse events reported in 5% of patients during treatment and 4% after treatment[5]. The trial's lead author described the finding as establishing prostate radiotherapy as a standard treatment option specifically for men with newly diagnosed metastatic disease and low metastatic burden, while noting it did not help men with higher burden disease[5].
How do metastatic and high-risk non-metastatic findings compare?
These are two different populations inside the same platform, and boards will test you on keeping them separate. The table below lines up the key comparisons by disease state.
Disease state | Intervention tested | Key result |
|---|---|---|
Metastatic (any burden) | Docetaxel + ADT | Improved median overall survival vs SOC alone[2] |
High-risk locally advanced or metastatic, starting ADT | Abiraterone + prednisolone | 37% relative reduction in risk of death, 83% vs 76% 3-year OS[3] |
High-risk, non-metastatic | Abiraterone + prednisolone | 86% vs 77% alive at 6 years[4] |
What does the platform trial design actually add?
The multi-arm, multi-stage design let STAMPEDE compare several interventions against one shared control group over time rather than running separate trials, each needing its own control arm recruited from scratch[1][2]. Men were allocated across arms using stratified randomization by minimisation, with unequal allocation ratios that put more patients into the shared control group relative to each experimental arm[2]. This is also why the trial could report that docetaxel and zoledronic acid findings showed no evidence of heterogeneity across prespecified subgroups, since a large shared control population gives more stable subgroup comparisons than a series of small individual trials would[2]. The tradeoff, visible in the radiotherapy results, is that a positive finding in the whole trial population can mask a null finding in a biologically distinct subgroup, and a null finding overall can hide a real benefit in a subgroup, which is exactly what happened with low versus high metastatic burden[5].
How do these results map onto current guideline practice?
The trial reports support these additions to long-term ADT: upfront docetaxel for suitable men starting long-term ADT for high-risk or metastatic disease, upfront abiraterone with prednisolone for men starting long-term ADT with high-risk locally advanced or metastatic disease, and prostate radiotherapy added to ADT specifically for men with newly diagnosed metastatic disease and low metastatic burden[1][2][3][5]. Zoledronic acid, by contrast, did not show a survival benefit and is not part of that standard[2]. Guideline detail and version-specific wording continue to evolve, and NCCN maintains its own current prostate cancer guideline pages that fellows should check directly for the latest version rather than relying on a single trial's findings in isolation[6]. For a related triplet regimen question that boards sometimes pair with STAMPEDE abiraterone data, note that darolutamide combined with ADT and docetaxel was tested in a separate phase III trial, ARASENS, built around a primary endpoint of overall survival in metastatic hormone-sensitive prostate cancer[7]; it is a different trial program from STAMPEDE but tests a related clinical question and is worth knowing by name.
What does the board exam actually test about STAMPEDE?
Know the population, not just the drugs. STAMPEDE enrolled men starting first-line long-term ADT, which includes high-risk locally advanced, node-positive, and metastatic disease, not a pure metastatic-only population[1][2].
Metastatic burden is the hinge for radiotherapy questions. Prostate radiotherapy helped only in low metastatic burden disease, defined by fewer than 4 bone metastases without visceral or extra-axial disease; it did not help high-burden disease[5].
Zoledronic acid and celecoxib are negative-result distractors. Expect these as wrong-answer choices designed to test whether you remember which STAMPEDE arms failed[1][2].
Know the toxicity tradeoffs. Both docetaxel and abiraterone increased severe adverse events relative to standard therapy, and boards like to test whether a benefit changes practice despite added toxicity[2][3].
If you are building this kind of trial knowledge into a study system rather than cramming it the week before boards, our physician-written question bank explains not just why abiraterone or docetaxel is the correct answer but why zoledronic acid and celecoxib are wrong, with direct PubMed links on every explanation. A trial like STAMPEDE, with its many arms and two distinct disease populations, is also a good candidate for turning into a Notebook mind map that links each arm, population, and result together rather than memorizing hazard ratios in isolation.
FAQ
What is the STAMPEDE trial in prostate cancer?
STAMPEDE is a multi-arm, multi-stage platform trial that randomized men starting first-line long-term androgen deprivation therapy for high-risk, locally advanced, or metastatic prostate cancer to standard of care or standard of care plus an additional intervention, with overall survival as the primary outcome[1][2].
What were the main STAMPEDE trial results?
Three additions to long-term hormone therapy improved survival in defined populations. Docetaxel improved median overall survival to 81 months from 71 months (HR 0.78)[2]. Abiraterone improved 3-year overall survival to 83% from 76%, a 37% relative reduction in the risk of death[3]. Prostate radiotherapy improved 3-year survival only in low-burden metastatic disease, 81% vs 73% (HR 0.68)[8]. Zoledronic acid did not improve survival (HR 0.94)[2].
Does STAMPEDE support abiraterone for all prostate cancer patients?
No. The abiraterone benefit was shown in men with high-risk locally advanced or metastatic prostate cancer starting long-term ADT for the first time, and a separate analysis in non-metastatic high-risk disease showed 86% versus 77% survival at 6 years[3][4]; STAMPEDE did not test abiraterone across all prostate cancer stages.
Why did zoledronic acid fail in STAMPEDE when docetaxel succeeded?
The trial shows that it failed, not why. Adding zoledronic acid gave a hazard ratio of 0.94 (95% CI 0.79 to 1.11, p=0.450), and the authors concluded it should not be part of standard of care[2]. Docetaxel, by contrast, improved survival (HR 0.78) at the cost of more grade 3 to 5 adverse events, 52% vs 32%[2]. The sources I reviewed do not offer a mechanistic explanation, so for a board question the safe answer is the data: no survival benefit, and no role as a routine addition.
Is prostate radiotherapy standard of care for metastatic prostate cancer?
Only for a subgroup. Radiotherapy to the prostate is a standard option for men with newly diagnosed metastatic disease and low metastatic burden, where 3-year overall survival was 81% vs 73% (HR 0.68, 95% CI 0.52 to 0.90)[8]. Across the whole trial there was no significant overall survival benefit (HR 0.92), and in high-burden disease there was none either (HR 1.07)[8].
Want trial-level detail like this built into spaced review instead of a one-time read? Our question bank is physician-written and physician-reviewed, never AI-generated, with explanations covering why each wrong answer is wrong and direct links to the primary literature. See how STAMPEDE-style trial questions are built into board prep at meducationai.com.
References
Combining existing drugs improves prostate cancer survival - Cancer Research UK - Cancer News
Radiation to Primary Tumor in Metastatic Prostate Cancer - The ASCO Post
NCCN Clinical Practice Guidelines in Oncology: Prostate Cancer | NCCN
Radiotherapy benefits some men whose prostate cancer has spread to their bones | NIHR Evidence
