Rezvilutamide in combination with androgen deprivation therapy (ADT) with or without docetaxel in the neoadjuvant treatment of oligometastatic prostate cancer (REDOOM): study protocol for an open-label, parallel-cohort, multicentre clinical study.

objectiveThis trial investigates the efficacy of neoadjuvant therapy using rezvilutamide combined with androgen deprivation therapy (ADT), with or without docetaxel, in treating oligometastatic hormone-sensitive prostate cancer (omHSPC). METHODS AND ANALYSIS: This prospective, open-label, multicentre trial aims to enrol 100 patients newly diagnosed with omHSPC (defined as ≤5 bone or lymph node metastases confirmed by conventional imaging, without visceral metastasis) who must express a desire to undergo surgery. All patients undergo a prostate-specific membrane antigen positron emission tomography/CT (PSMA-PET/CT) scan at enrolment or within 4 weeks before enrolment to assess and confirm the number of metastases at baseline. Scans should be performed before initiating ADT to avoid compromising test sensitivity. Then patients will be allocated into groups in parallel according to their own preferences: one group will receive an LHRH agonist or antagonist for 24 weeks to maintain continuous ADT or have undergone bilateral orchiectomy. Treatment with rezvilutamide will be maintained daily. The other group will be scheduled to complete up to six cycles of docetaxel within 24 weeks, with maintenance of continuous ADT and rezvilutamide for 24 weeks. Both groups will receive a conventional imaging evaluation at the 12th week. After neoadjuvant therapy, patients will undergo conventional imaging and a second PSMA-PET/CT assessment, followed by cytoreductive radical prostatectomy within the subsequent 6 weeks. After surgery, patients may choose to continue with ADT or rezvilutamide at their own discretion, until disease progression. The primary endpoint is pathological complete response, defined as the absence of residual viable tumour cells in the tumour bed on pathological evaluation of the postoperative specimen. Secondary endpoints include 1 year biochemical progression-free survival, overall survival, radiographic progression-free survival, time to prostate-specific antigen progression, quality of life scores (total and subscale) assessed using the Functional Assessment of Cancer Therapy-Prostate questionnaire, time to symptomatic progression, time to deterioration in Eastern Cooperative Oncology Group performance status, the interval from enrolment to an increase in score from baseline, the proportion of patients with a ≥30% reduction in prostate volume on imaging before cytoreductive surgery compared with pre-neoadjuvant therapy, minimal residual disease and major pathological response. The study plans to enrol a total of 100 patients. Patient recruitment for this study is scheduled to begin in May 2025. ETHICS AND DISSEMINATION: This has been approved by the Ethics Committee in Clinical Research of the First Affiliated Hospital of Wenzhou Medical University (number KY2024-231). Results will be published in peer-reviewed publications. DISCUSSION: This study is expected to provide prospective evidence on the feasibility and potential clinical value of rezvilutamide combined with ADT, with or without docetaxel, as neoadjuvant treatment for newly diagnosed omHSPC. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry (ChiCTR2400093262).