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

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.

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).

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.

"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."

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).

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