Multimodal Prehabilitation and Rehabilitation for Men Undergoing Robot-Assisted Radical Prostatectomy

The ROBOPREP Trial is a hybrid type 1 multicentre, assessor-blinded, parallel-group randomised controlled trial with nested qualitative and cost-effectiveness appraisal. The trial evaluates a virtually delivered, self-directed multimodal (p)rehabilitation program for men undergoing robot-assisted radical prostatectomy (RARP) for prostate cancer. Background: Erectile dysfunction (ED) occurs in 25-75% of men following RARP, with unassisted recovery of erectile function in only 20-25%. Urinary incontinence affects a further 27-40%. Current evidence supports early initiation of phosphodiesterase type 5 inhibitors (PDE5i), pelvic floor muscle training (PFMT), and psychological interventions, but no multimodal perioperative program combining all modalities has been evaluated in a rigorous RCT. Intervention: Participants randomised to the intervention arm receive, in addition to standard care: (1) tadalafil 5 mg/day orally commencing 4 weeks preoperatively, ceasing during hospital admission, and resuming for 3 months following postoperative catheter removal; (2) pelvic floor muscle training (3 sets/day: 20 fast and 20 slow contractions); (3) aerobic exercise (40 min, 4×/week, moderate-to-vigorous intensity); (4) nutritional guidance; and (5) psychological strategies including relaxation, psychoeducation, and self-compassion. Non-pharmacological components are delivered via a co-designed digital booklet and avatar videos. All components are self-directed to ensure scalability. Randomisation and Blinding: Randomisation (1:1, stratified by age ≤60 vs \>60 years, and nerve spare expected \>50% bilateral or unilateral 100%, permuted blocks of size 2 and 4) is managed via a central secure REDCap randomisation module uploaded by an independent research officer. Outcome assessors are blinded to allocation; blinding of participants and treating clinicians is not feasible given the nature of the intervention. Statistical Analysis: Primary analysis is intention-to-treat. The primary outcome (IIEF-5 at 3 months postoperatively) will be compared between arms using Mann-Whitney U tests and multivariate regression adjusting for baseline characteristics. Secondary outcomes will be analysed using mixed models, Cox regression (time to continence), and chi-square or Fisher's exact tests as appropriate. The trial medication is funded by Generic Health (Lupin), who provide a donation covering participant reimbursement for tadalafil 5 mg (4-month supply; approx. AUD $120-150 per participant) and the TGA CTN application fee. Tadalafil 5 mg is TGA-approved for erectile dysfunction (ARTG: 289541).