A Randomised Controlled Platform Trial Testing Treatments in Metastatic Hormone Sensitive Prostate Cancer

Summary

STAMPEDE2 is a clinical trial comparing two new treatments with standard of care in people with prostate cancer that has spread to other parts of the body and is responsive to hormone therapy. People from all backgrounds and ethnicities are encouraged to take part and multiple hospitals across the UK are involved. University College London is running the trial.

Each comparison within the trial has its own control arm where people get the best standard of care (Arm A) versus a research arm where a new treatment is added to standard of care.

Participants are allocated to an arm by a computerised system with a 50% chance of getting the research treatment.

Comparison S: Arm A versus Arm S (Stereotactic Ablative Body Radiotherapy (SABR)) - Tests whether giving targeted doses of radiotherapy (SABR) to parts of the body where the cancer has spread slows the spread of the cancer and improves survival. 2476 people will be in this comparison.

Comparison P: Arm A versus Arm P (PSMA-Lutetium (177Lu-PSMA-617)) - Tests whether giving a radioactive material (177Lu-PSMA-617) that targets prostate cancer cells slows the spread of the cancer and improves survival. 1756 people will be in this comparison.

All participants will be followed up with scans and tests to monitor their cancer. Doctors will check for any side effects from the treatments. Treatments will be stopped if side effects are serious, or people no longer wish to take the treatments.

Conditions

• Prostate Cancer Metastatic

Interventions

RADIATION

Stereotactic Ablative Body Radiotherapy (SABR)

SABR is a way of giving focused high-dose radiotherapy. SABR given with a dose fractionation schedule of 27-30Gy in 3-5 fractions over 1-2 weeks to up to 5 metastatic lesions in the bone and/or non-regional (extra-pelvic) lymph nodes.

OTHER

177Lu-PSMA-617

177Lu-PSMA-617 is a nuclear medicine therapy. Patients will receive 177Lu-PSMA-617 to a dose of 7.4GBq. Each cycle will consist of 2 doses, 1 week apart (on day 1 and day 8) and will last 6 weeks. Treatment will be given for up to 3 cycles (6 doses).

DRUG

Androgen Deprivation Therapy (ADT)

Long-term, continuous treatment with ADT (bilateral orchidectomy, LHRH agonists or LHRH antagonists) if not previously surgically castrated. The choice of ADT is at the discretion of the investigator. This will be given as standard of care as per local guidelines.

DRUG

Androgen Receptor Signalling Inhibitor (ARPI)

Second generation ARPI (Abiraterone Acetate and Prednisolone, Enzalutamide, Apalutamide or Darolutamide). This will be given as standard of care as per local guidelines. Abiraterone acetate will be administered as a single 1000mg once daily dose (4 tablets to be taken together once a day) with prednisolone 5mg once daily to prevent secondary mineralocorticoid excess. Enzalutamide will be administered as a 160mg oral dose (four capsules taken together at the same time every day) with or without food. Enzalutamide is administered daily in 28-day cycles. Apalutamide will be administered as 240mg oral dose (four tablets taken together at the same time every day) with or without food. Apalutamide is administered daily in 28-day cycles. Patients require thyroid function monitoring. Darolutamide will be administered as 600mg oral dose (two 300mg tablets taken together) with or without food. Darolutamide is administered twice daily in 28-day cycles.

RADIATION

Radiotherapy to Prostate ± Pelvic Nodes

Either 36.25Gy given in 5 fractions over 1-2 weeks to prostate or 60Gy in 20 fractions over 4 weeks to prostate (± 44-47Gy in 20 fractions to pelvic lymph nodes ± 51Gy in 20 fractions boost to involved nodes).

DRUG

Docetaxel

Maximum of 6 cycles every 3 weeks may be given at a dose of 75mg/m2 by IV infusion.

Sponsors & Collaborators

• Cancer Research UK

  collaborator OTHER

• Novartis

  collaborator INDUSTRY

• University College, London

  lead OTHER

Principal Investigators

• Louise Brown · MRC CTU at UCL

• Nick James · Institute of Cancer Research, United Kingdom

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

MALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-06-11

Primary Completion

2031-04-30

Completion

2032-03-31

Countries

• United Kingdom

Study Locations